when did top of the pops go live

Top of the Pops was first broadcast on Wednesday, 1 January 1964 at 6:35 pm. It was produced in Studio A on Dickenson Road in Rusholme, Manchester.

Top of the Pops

Top of the Pops, also known as TOTP, is a British music chart television programme, made by the BBC and originally broadcast weekly between 1 January 1964 and 30 July 2006. It was traditionally shown every Thursday evening on BBC One, except for a short period on Fridays in mid-1973 before being again moved to Fridays in 1996 and then to Sundays on BBC Two in 2005. Each weekly programme consisted of performances from some of that week's best-selling popular music artists, with a rundown of that week's singles chart. Additionally, there was a special edition of the programme on Christmas Day (and usually, until 1984, a second such edition a few days after Christmas), featuring some of the best-selling singles of the year.

With its high viewing figures, the show became a significant part of British popular culture. Although the weekly show was cancelled in 2006,[2] the Christmas special has continued.[3][4][5] It also survives as Top of the Pops 2, which began in 1994 and features vintage performances from the Top of the Pops archives.

In the 1990s, the show's format was sold to several foreign broadcasters in the form of a franchise package, and at one point various versions of the show were shown in nearly 100 countries. Editions of the programme from the 1970s (and now 1980s) are being repeated on most Thursdays and Fridays on BBC Four, although episodes featuring disgraced presenters and artists such as Jimmy Savile, Dave Lee Travis and Gary Glitter are not repeated.[6]

Top of the Pops was created by BBC producer Johnnie Stewart, inspired by the popular Teen and Twenty Disc Club which aired on Radio Luxembourg. It was first aired in 1964 and was originally based on the Top 20. By 1970 the Top 30 was being used and the show was extended from 30 to 45 minutes duration. The show was also now shown in colour following the BBC1 upgrade in November 1969. A switch to the Top 40 was made in 1984. (Radio One also changed to the Top 30 in the early 70s and to the Top 40 in 1978).

The show saw many changes through the decades, in style, design, fashion and taste. It periodically had some aspect of its title sequence, logo and theme tune, format, or set design altered in some way, keeping the show looking modern despite its age. The programme had several executive producers during its run (although not all were billed as such), in charge of the overall production of the show, although specific content on individual shows was sometimes decided by other producers. When Stewart left the show in 1973, after nearly 10 years in charge, he was replaced by Robin Nash. Both Stewart and Nash made brief returns to the show as producer after they left, in 1976 and 1981 respectively.

Stewart devised the rules which governed how the show would operate: the programme would always end with the number one record, which was the only record that could appear in consecutive weeks. The show would include the highest new entry and (if not featured in the previous week) the highest climber on the charts, and omit any song going down in the chart.[7] Tracks could be featured in consecutive weeks in different formats. For example, if a song was played over the chart countdown or the closing credits, then it was acceptable for the act to appear in the studio the following week.

These rules were sometimes interpreted flexibly and were more formally relaxed from 1997 when records descending the charts were featured more regularly, possibly as a response to the changing nature of the Top 40 (in the late 1990s and early 2000s climbers in the charts were a rarity, with almost all singles peaking at their debut position).

When the programme's format changed in November 2003, it concentrated increasingly on the top 10. Later, during the BBC Two era, the top 20 was regarded as the main cut-off point, with the exception made for up and coming bands below the top 20. Singles from below the top 40 (within the top 75) were shown if the band were up and coming or had a strong selling album. If a single being performed was below the top 40, just the words "New Entry" were shown and not the chart position.

The show was originally intended to run for only a few programmes but lasted over 42 years, reaching landmark episodes of 500, 1,000, 1,500 and 2,000 in the years 1973,[8] 1983,[9] 1992 and 2002[10] respectively.

DJ Jimmy Savile presented the first show live from the Manchester studio (with a brief link to Alan Freeman in London to preview the following week's programme), which featured (in order) the Rolling Stones with "I Wanna Be Your Man", Dusty Springfield with "I Only Want to Be with You", the Dave Clark Five with "Glad All Over", the Hollies with "Stay", the Swinging Blue Jeans with "Hippy Hippy Shake" and the Beatles with "I Want to Hold Your Hand",[11] that week's number one â€“ throughout its history, the programme proper always (with very few exceptions) finished with the best-selling single of the week, although there often was a separate play-out track.

Later in 1964, the broadcast time was moved to one hour later, at 7:35 pm, and the show moved from Wednesdays to what became its regular Thursday slot. Additionally its length was extended by 5 minutes to 30 minutes.

For the first three years Alan Freeman, David Jacobs, Pete Murray and Jimmy Savile rotated presenting duties, with the following week's presenter also appearing at the end of each show, although this practice ceased from October 1964 onwards. Neville Wortman filled in as director/producer on Johnnie Stewart's holiday break.

In the first few editions, Denise Sampey was the "disc girl", who would be seen to put the record on a turntable before the next act played their track.[12] However, a Mancunian model, Samantha Juste, became the regular disc girl after a few episodes, a role she performed until 1967.[13]

With the birth of BBC Radio 1 in 1967, new Radio 1 DJs were added to the roster â€“ Stuart Henry, Emperor Rosko, Simon Dee and Kenny Everett.[14]

Local photographer Harry Goodwin was hired to provide shots of non-appearing artists, and also to provide backdrops for the chart run-down. He would continue in the role until 1973.[15]

After two years at the Manchester Dickenson Road Studios, the show moved to London (considered to be better located for bands to appear), initially for six months at BBC TV Centre Studio 2 and then to the larger Studio G at BBC Lime Grove Studios in mid-1966[16] to provide space for the Top of the Pops Orchestra, which was introduced at this time to provide live instrumentation on some performances (previously, acts had generally mimed to the records). In November 1969, with the introduction of colour, the show returned to BBC TV Centre, where it stayed until 1991, when it moved to Elstree Studios Studio C.[17]

For a while in the early 1970s, non-chart songs were played on a more regular basis, to reflect the perceived growing importance of album sales, as well as a New Release spot and a feature of a new act, dubbed Tip for the Top. These features were dropped after a while, although the programme continued to feature new releases on a regular basis for the rest of the decade.

During its heyday, it attracted 15 million viewers each week. The peak TV audience of 19 million was recorded in 1979, during the ITV strike, with only BBC1 and BBC2 on air.[18]

A year end Christmas show featuring a'review' of the year's biggest hits was inaugurated on 24 December 1964, and has continued every year since.[19] From 1965 onwards, the special edition was broadcast on Christmas Day[20] (although not in 1966[21]) and from the same year, a second edition was broadcast in the days after Christmas, varying depending on the schedule, but initially regularly on 26 December. The first was shown on 26 December 1965.[22] The second programme was discontinued after 1984. In 1973, there was just one show, airing on Christmas Day. In place of the traditional second show, Jimmy Savile hosted a look back at the first 10 years of TOTP, broadcast on 27 December.[23] In 1975, the first of the two shows was broadcast prior to Christmas Day, airing on 23 December, followed by the traditional Christmas Day show two days later.[24]

The 1978 Christmas Day show was disrupted due to industrial action at the BBC, requiring a change in format to the broadcast. The first show, due to be screened on 21 December, was not shown at all because BBC1 was off the air.[25] For Christmas Day, Noel Edmonds (presenting his last ever edition of TOTP) hosted the show from the 'TOTP Production Office' with clips taken from various editions of the show broadcast during the year and new studio footage performed without an audience. The format was slightly tweaked for the Christmas Day edition in 1981, with the Radio 1 DJs choosing their favourite tracks of the year[26] and the following edition on 31 December featuring the year's number 1 hits.[27]

In 1980, Nash was replaced by Michael Hurll, who introduced more of a "party" atmosphere to the show, with performances often accompanied by balloons and cheerleaders, and more audible audience noise and cheering. Guest co-presenters and a music news feature were introduced for a short while, but had ceased by the end of 1980. The chart rundown was split into three sections in the middle of the programme, with the final Top 10 section initially featuring clips of the songs' videos, although this became rarer over the next few years. An occasional feature showing the American music scene with Jonathan King was introduced in November 1981, and ran every few weeks until February 1985. In January 1985, a Breakers section, featuring short video clips of new tracks in the lower end of the Top 40, was introduced, and this continued for most weeks until March 1994.

Although the programme had been broadcast live in its early editions, it had been recorded on the day before transmission for many years. However, from May 1981, the show was sometimes broadcast live for a few editions each year, and this practice continued on an occasional basis (often in the week of a bank holiday, when the release of the new chart was delayed, and for some special editions) for the rest of the decade.

The programme moved in September 1985 to a new regular half-hour timeslot of 7pm on Thursdays, where it would remain until June 1996.

The end of 1988 was marked by a special 70-minute edition of the show broadcast on 31 December 1988, to celebrate the 25th anniversary of the first show. The pre-recorded programme featured the return of the original four presenters (Savile, Freeman, Murray and Jacobs) as well as numerous presenters from the show's history, anchored by Paul Gambaccini and Mike Read. Numerous clips from the history of the show were included in between acts performing in the studio, which included Cliff Richard, Engelbert Humperdinck, Lulu, The Four Tops, David Essex, Mud, Status Quo, Shakin' Stevens, The Tremeloes and from the very first edition, The Swinging Blue Jeans. Sandie Shaw, The Pet Shop Boys and Wet Wet Wet were billed in the Radio Times to appear, but none featured in the show other than Shaw in compilation clips.[28]

Paul Ciani took over as producer in 1988. The following year, in an attempt to fit more songs in the allocated half hour, he restricted the duration of studio performances to three minutes, and videos to two minutes, a practice which was largely continued until May 1997. In July 1990, he introduced a rundown of the Top 5 albums, which continued on a monthly basis until May 1991. Ciani had to step down due to illness in 1991, when Hurll returned as producer to cover for two months (and again for a brief time as holiday cover in 1992).

From 1967, the show had become closely associated with the BBC radio station Radio 1, usually being presented by DJs from the station, and between 1988 and 1991 the programme was simulcast on the radio station in FM stereo. However, during the last few years of the 1980s the association became less close, and was severed completely (although not permanently) in a radical shake-up known as the 'Year Zero' revamp.

Following a fall in viewing figures and a general perception that the show had become 'uncool' (acts like The Clash had refused to appear in the show in previous years), a radical new format was introduced by incoming executive producer Stanley Appel (who had worked on the programme since 1966 as cameraman, production assistant, director and stand-in producer[29]) in October 1991, in which the Radio 1 DJs were replaced by a team of relative unknowns, such as Claudia Simon and Tony Dortie who had previously worked for Children's BBC, 17-year-old local radio DJ Mark Franklin, Steve Anderson, Adrian Rose and Elayne Smith, who was replaced by Femi Oke in 1992. A brand new theme tune ('Now Get Out Of That'), title sequence and logo were introduced, and the entire programme moved from BBC Television Centre in London to BBC Elstree Centre in Borehamwood.

The new presenting team would take turns hosting (initially usually in pairs but sometimes solo), and would often introduce acts in an out-of-vision voiceover over the song's instrumental introduction. They would sometimes even conduct short informal interviews with the performers, and initially the Top 10 countdown was run without any voiceover. Rules relating to performance were also altered meaning acts had to sing live as opposed to the backing tracks for instruments and mimed vocals for which the show was known. To incorporate the shift of dominance towards American artists, more use was made of out-of-studio performances, with acts in America able to transmit their song to the Top of the Pops audience "via satellite". These changes were widely unpopular and much of the presenting team were axed within a year, leaving the show hosted solely by Dortie and Franklin (apart from the Christmas Day editions, when both presenters appeared) from October 1992, on a week-by-week rotation.

By 1994, much of the 'Year Zero' revamp was quickly undone and the arrival of Ric Blaxill as producer in February 1994 signalled a return to presentation from established Radio 1 DJs Simon Mayo, Mark Goodier, Nicky Campbell and Bruno Brookes. Blaxill expanded the use of "via satellite" performances, taking the acts out of studios and concert halls and setting them against landmark backdrops. As a consequence, Bon Jovi performed Always from Niagara Falls and Celine Dion beamed in Think Twice from Miami Beach.

The last remnants of the Year Zero revamp were replaced in 1995, when a new title sequence, logo and theme tune were introduced (the logo having first been introduced on the new programme Top of the Pops 2 some months previous), coinciding with the introduction of a new set. Blaxill also increasingly experimented with handing presenting duties to celebrities, commonly contemporary comedians and pop stars who were not in the charts at that time. In an attempt to keep the links between acts as fresh as the performances themselves, the so-called "golden mic" was used by, amongst others, Kylie Minogue, Meat Loaf, Des Lynam, Chris Eubank, Damon Albarn, Harry Hill, Jack Dee, Lulu and Jarvis Cocker. Radio 1 DJs still presented occasionally, notably Lisa I'Anson, Steve Lamacq, Jo Whiley and Chris Evans.

TOTP was traditionally shown on a Thursday night, but was moved to a Friday starting on 14 June 1996,[30] originally at 7 pm, but then shifted to 7.30 pm, a change which placed the programme up against the soap opera Coronation Street on ITV. This began a major decline in audience figures as fans were forced to choose between Top of the Pops and an episode of the soap.[31]

In 1997, incoming producer Chris Cowey phased out the use of celebrities and established a rotating team (similar to the 1991 revamp, although much more warmly received) of former presenters of youth music magazine The O-Zone Jayne Middlemiss and Jamie Theakston as well as Radio 1 DJs Jo Whiley and Zoë Ball. The team was later augmented by Kate Thornton and Gail Porter.

Chris Cowey in particular instigated a set of 'back to basics' changes when he took over the show. In 1998, a remixed version of the classic 'Whole Lotta Love' theme tune previously used in the 1970s was introduced, accompanied by a new 1960s-inspired logo and title sequence. Cowey also began to export the brand overseas with localised versions of the show on air in Germany, France, the Netherlands, Belgium and Italy by 2003.[32] Finally, the programme returned to its previous home of BBC Television Centre in 2001, where it remained until its cancellation in 2006.

On 28 November 2003 (three months after the appointment of Andi Peters as executive producer), the show saw one of its most radical overhauls since the ill-fated 1991 'Year Zero' revamp in what was widely reported as a make-or-break attempt to revitalise the long-running series. In a break with the previous format, the show played more up-and-coming tracks ahead of any chart success, and also featured interviews with artists and a music news feature called "24/7". Most editions of the show were now broadcast live, for the first time since 1991 (apart from a couple of editions in 1994). The launch show, which was an hour long, was notable for a performance of "Flip Reverse" by Blazin' Squad, featuring hordes of hooded teenagers choreographed to dance around the outside of BBC Television Centre.

Although the first edition premiÃ¨red to improved ratings, the All New format, hosted by MTV presenter Tim Kash, quickly returned to low ratings and brought about scathing reviews.[33][34] Kash continued to host the show, but Radio 1 DJs Reggie Yates and Fearne Cotton (who had each presented a few shows in 2003, before the revamp) were brought back to co-host alongside him, before Kash was completely dropped by the BBC, later taking up a new contract at MTV. The show continued to be hosted by Reggie Yates and Fearne Cotton (usually together, but occasionally solo) on Friday evenings until 8 July 2005.

On 30 July 2004, the show took place outside a studio environment for the first time by broadcasting outside in Gateshead. Girls Aloud, Busted, Will Young and Jamelia were among the performers that night.[35]

By November 2004, viewing figures had plummeted to below three million, prompting an announcement by the BBC that the show was going to move, again, to Sunday evenings on BBC Two, thus losing the prime-time slot on BBC One that it had maintained for more than forty years.[36]

This move was widely reported as a final "sidelining" of the show, and perhaps signalled its likely cancellation. At the time, it was insisted that this was so that the show would air immediately after the official announcement of the new top 40 chart on Radio 1, as it was thought that by the following Friday, the chart seemed out-of-date. The final Top of the Pops to be shown on BBC One (barring Christmas and New Year specials) was broadcast on Monday 11 July 2005, which was edition number 2,166.

The first edition on BBC Two was broadcast on 17 July 2005 at 7.00pm with presenter Fearne Cotton. After the move to Sundays, Cotton continued to host with a different guest presenter each week, such as Rufus Hound or Richard Bacon. On a number of occasions, however, Reggie Yates would step in, joined by female guest presenters such as Lulu and Anastacia. Viewing figures during this period averaged around 1Â½ million. Shortly after the move to BBC Two, Peters resigned as executive producer.[37] He was replaced by the BBC's Creative Head of Music Entertainment Mark Cooper, while producer Sally Wood remained to oversee the show on a weekly basis.

On 20 June 2006, the show was formally cancelled and it was announced that the last edition would be broadcast on 30 July 2006. Edith Bowman co-presented its hour-long swansong, along with Jimmy Savile (who was the main presenter on the first show), Reggie Yates, Mike Read, Pat Sharp, Sarah Cawood, Dave Lee Travis, Rufus Hound, Tony Blackburn and Janice Long.

The final day of recording was 26 July 2006[38] and featured archive footage and tributes, including the Rolling Stones – the very first band to appear on Top of the Pops – opening with "The Last Time", the Spice Girls, David Bowie, Wham!, Madonna, Beyoncé, Gnarls Barkley, the Jackson 5, Sonny and Cher and Robbie Williams. The show closed with a final countdown, topped by Shakira, as her track "Hips Don't Lie" (featuring Wyclef Jean) had climbed back up to number one on the UK Singles Chart earlier in the day. The show ended with Savile ultimately turning the lights off in the empty studio.

Fearne Cotton, who was the current presenter, was unavailable to co-host for the final edition due to her filming of ITV's Love Island in Fiji but kicked off the show with a quick introduction recorded on location, saying "It's still number one, it's Top of the Pops". BARB reported the final show's viewing figures as 3.98 million.[39]

Since the last episode featured no live acts in the studio, the honour of being the last act to actually perform on a weekly episode of TOTP goes to Snow Patrol with "Chasing Cars" in the penultimate edition; the last act ever featured visually on a weekly Top of the Pops was Girls Aloud, as part of the closing sequence of bands performing on the show throughout the years. They were shown performing "Love Machine".

The magazine and TOTP2 have both survived despite the show's axing, and the Christmas editions also continue after returning to BBC One. However, the TOTP website, which the BBC had originally promised would continue, is now no longer updated, although many of the old features of the site – interviews, music news, reviews – have remained, now in the form of the Radio 1-affiliated TOTP ChartBlog accessible via the remains of the old website.

In October 2008, British Culture Secretary Andy Burnham and Manchester indie band the Ting Tings called for the show to return.[40]

On 29 October 2008, Simon Cowell stated in an interview that he would be willing to buy the rights to Top of the Pops from the BBC. The corporation responded that they had not been formally approached by Cowell,[41] and that in any case the format was not "up for sale".[5] In November 2008, it was reported by The Times and other newspapers that the weekly programme was to be revived in 2009, but the BBC said there were no such plans.[42]

In July 2009, Pet Shop Boys singer Neil Tennant criticised the BBC for ending the programme, stating that new acts were missing out on "that great moment of being crowned that week's Kings of Pop".[43]

In early 2015 there was increased speculation of a return of the show including rumours that Dermot O'Leary might present alongside Fearne Cotton. According to a report in the Daily Mirror, a BBC insider stated that ″some at the highest level are massive supporters of the plan [of a return] and have given the go-ahead."[44] The move of the UK charts to a Friday due to take place in summer 2015[45] was also said to favour the possibility of a return, making it ″the perfect tie-in″[44] and a ″perfect start to the weekend″,[44] but no weekly return has occurred.

In April 2011, the BBC began to reshow Top of the Pops on Thursday nights on BBC Four beginning with the equivalent show from 35 years earlier in a 7:30pmâ€“8:00pm slot approximating to the time the programme was traditionally shown. The first programme shown, 1 April 1976, was chosen because it was from approximately this episode onwards that most editions remain in the BBC archive. The repeat programmes come in two versions; the first is edited down to fit in the 30 minute 7:30 slot, the second is shown normally twice overnight in the following weekend, and is usually complete. However both the short and longer editions can be edited for a number of reasons. Potentially offensive content to modern audiences is cut (for example the Barron Knights' in-studio performance of "Food For Thought" on the 13 December 1979 edition including a segment parodying Chinese takeaways using mannerisms that may now be viewed as offensive), and cinematic film footage can be truncated, replaced or removed entirely due to the costs to the BBC of reshowing such footage. The BBC also makes the repeats available on BBC iPlayer. The repeats are continuing as of July 2017 with episodes from 1984.[46]

Following the Jimmy Savile allegations, from October 2012, episodes featuring Jimmy Savile ceased to be broadcast.[47] Following the arrest of Dave Lee Travis by Operation Yewtree officers, and the subsequent prosecution, acquittal, retrial, further acquittal on all but one minor charge and failed appeal, episodes featuring Travis were also omitted.[48] Episodes featuring Mike Smith are also not included in the run due to the presenter declining to sign licence extensions to permit rebroadcast. Smith died in August 2014 and the BBC continues to honour his wishes.[49] Due to these broadcasting restrictions and the occasional missed weeks in the original run due to strikes and other reasons (an episode was not made for 1 June 1978 due to the BBC showing the 1978 FIFA World Cup[50]), other programmes are shown on some Thursday nights to make up the shortfall in the number of programmes in a given year, in particular The Sky At Night and The BBC Proms.

Prior to the 1976 BBC reruns shown in 2011, the BBC produced a special programme, "The Story Of 1976".[51] This comprised excerpts from the 1976 programmes, interspersed with new interviews with people discussing the time period. They have produced similar programmes prior to subsequent annual reruns for 1977 in 2012,[52] 1978 in 2013,[53] 1979 in 2014,[18] 1980 in 2015,[54] 1981 on 8 January and 1982 in 17 June 2016 and 1983 and 1984 on 6 January 2017 and 4th June 2017 etc.[55]

A series of compilation of big hits with captions on the screen about artist, people and songs from 1964â€“1975 and 1976 in 2011, 1977 in 2012, 1978 in 2013, 1979 in 2014, 1980 in 2015 and both 1981 in 8 January 2016 and 1982 in 17 June 2016 etc.

Although the weekly Top of the Pops has been cancelled, the Christmas Specials have continued, hosted by Fearne Cotton and Reggie Yates. The Christmas specials are broadcast on Christmas Day afternoon on BBC One. Since 2008[56] (apart from 2010 and 2011), a New Year special has also been broadcast. The most recent festive editions of Top of the Pops were at the end of 2017, on Christmas Day and New Year's Eve.[57] A new logo and title sequence were introduced from 2013, although earlier versions of the logo still appear on the studio set. The BBC's Head of Music Television, Mark Cooper, continues to oversee the programme as executive producer, while Stephanie McWhinnie replaced Wood as producer with effect from Christmas 2011. On 4 December 2017, Yates stepped down from hosting Top of the Pops due to comments he made regarding Jewish people and rappers.[58] The BBC later announced Clara Amfo as Yates' replacement.[59]

The show was given a one-off revival (of sorts) for Comic Relief 2007 in the form of Top Gear of the Pops, presented by Jeremy Clarkson, Richard Hammond and James May. It was filmed at the Top Gear aerodrome studio in Surrey on Sunday, 11 March 2007, although it bore little resemblance to the usual Top of the Pops format.

On 13 March 2009, Top of The Pops was once again revived, this time in its usual format, for a special live Comic Relief edition, airing on BBC Two while the main telethon took a break for the BBC News at Ten on BBC One. As with the Christmas specials the show was presented by Radio 1 duo Fearne Cotton and Reggie Yates with special guest presenter Noel Fielding and appearances from Dawn French, Jennifer Saunders, Claudia Winkleman, Jonathan Ross, Davina McCall (dancing in the audience and later as a Flo Rida dancer with Claudia Winkleman and French and Saunders) and David Tennant.

Live performances – interspersed with Comic Relief appeal films – included acts such as Franz Ferdinand, Oasis, Take That, U2, James Morrison and Flo Rida (that week's Number 1). Kicking off the show was a performance from Rob Brydon and Ruth Jones in their Gavin & Stacey guises, feat. Tom Jones and Robin Gibb with "(Barry) Islands in the Stream", the Comic Relief single.

In its extensive history, Top of the Pops has featured many artists, many of whom have appeared more than once on the show to promote many of their records.

Green Day hold the record for the longest Top of the Pops performance: "Jesus of Suburbia" broadcast on 6 November 2005, lasted 9 minutes and 10 seconds. There is uncertainty about what was the shortest performance. In 2005, presenter Reggie Yates announced on the show that it was Super Furry Animals with "Do or Die", broadcast on 28 January 2000, clocking in at 95 seconds. However, "It's My Turn" by Angelic was 91 seconds on 16 June 2000 and, according to an August 2012 edition of TOTP2, "Here Comes the Summer" by the Undertones was just 84 seconds on 26 July 1979. Cliff Richard appeared the most times on the show, with almost 160 performances. Status Quo were the most frequent group with 106 performances.[60]

Initially acts performing on the show mimed to the commercially released record, but in 1966 after discussions with the Musicians' Union, miming was banned.[61] After a few weeks during which some bands' attempts to play as well as on their records were somewhat lacking, a compromise was reached whereby a specially recorded backing track was permitted â€“ as long as all the musicians on the track were present in the studio.[62][63] The TOTP Orchestra, led by Johnny Pearson, augmented the tracks when necessary. This set-up continued until 1980, when a protracted Musicians' Union strike resulted in the dropping of the live orchestra altogether and the use of pre-recorded tracks only.[64] This accounts for a number of acts who never appeared on the show due to their reluctance to perform in this way. Highlights have included Jimi Hendrix who, on hearing someone else's track being played by mistake (in the days of live broadcast), mumbled "I don't know the words to that one, man", Shane MacGowan of The Pogues' drunken performance of "Fairytale of New York", a performance of "Roll with It" by Oasis in which Noel and Liam Gallagher exchanged roles with Noel miming to Liam's singing track and Liam pretending to play guitar, and John Peel's appearance as the mandolin soloist for Rod Stewart on "Maggie May".

The miming policy also led to the occasional technical hitch. A famous example of this is the performance of "Martha's Harbour" in 1988 by All About Eve where the television audience at home could hear the song but the band and studio audience and personnel could not. As the opening verse of the song beamed out of the nation's television sets, the unknowing lead singer Julianne Regan remained silent on a stool on stage while Tim Bricheno (the only other band member present) did not play his guitar. An unseen stagehand apparently prompted them that something was wrong in time to mime along to the second verse. The band were invited back the following week, and chose to sing live.[citation needed]

Occasionally bands played live, examples in the 1970s being The Four Seasons, The Who, John Otway, Sham 69, Eddie and the Hot Rods, Jimmy James and the Vagabonds, Heavy Metal Kids, Elton John, Typically Tropical, New Order, and David Bowie. In 1980, heavy metal band Iron Maiden played live on the show when they refused to mime to their single "Running Free". Solo artists and vocal groups were supposed to sing live to the Top Of The Pops Orchestra. Billy Ocean, Brotherhood Of Man, Hylda Baker and The Nolans all performed in this way.

For a few years from 1991, the show adopted a live vocal to pre-recorded backing track policy. Performing "Smells Like Teen Spirit", Nirvana singer Kurt Cobain dropped his voice an octave and changed the opening line to "Load up on drugs, kill your friends"; the band also made it very clear that they were not playing their instruments. (Cobain later said during an interview that he wanted to sound more like Morrissey during the performance.) It also exposed a number of poor live singers, and was dropped as a general rule.[65] It was not helped by the fact that it coincided with a sudden upsurge of chart success for dance tracks which were heavily sample-based and whose sound could not easily be reproduced in a TV studio â€“ sampled vocals from other tracks had to be sung live.[citation needed]

In its final few years miming had become less and less common, especially for bands, as studio technology became more reliable and artists were given the freedom to choose their performance style. Former Executive Producer Andi Peters stated that there was no policy on miming and said that it was entirely up to the performer if they wanted to sing live or mime.[66]

In the era before promotional videos were routinely produced for every charting single, the BBC would frequently have neither the band themselves nor alternative footage available for a song selected for the programme. In the first few months of the show in 1964, the director would just scan across the audience dancing in the absence of any other footage, but by October 1964 a decision was made to at least occasionally bring in a dance troupe with a choreographed routine to some of the tracks.[67]

An initial candidate troupe was the existing BBC TV Beat Girls, but an ex-dancer from the Beat Girls, Jo Cook, was eventually engaged to create a troupe, the all-female Go-Jos.,[68][69] with Cook as choreographer. The Go-Jos also worked outside of Top of the Pops, notably for two years on the Val Doonican show[70] â€“ Doonican said in 1968 "I thought the Gojos were fabulous, something really new. When I got my own television series I just had to have them with me."[71]

They were initially a three-piece (Pat Hughes for the first edition only, Linda Hotchkin and Jane Bartlett), but their number eventually grew to six (Hotchkin, Bartlett, Lesley Larbey, Wendy Hilhouse, Barbara van der Heyde and Thelma Bignell) with Cook as full-time choreographer. Lulu remembered of their costumes "They mostly wore white boots to the knee and short skirts and the camera would go up the skirt and it was all very risquÃ©."[72]

Cook herself said of working on the Doonican show (of which she was dance director) comparing to Top of the Pops, "Pop steps are limited...With Val we have more scope, and we can work to get more of the feel of ballet into our numbers."[71]

In April 1968, a Top of the Pops choreographer, Virginia Mason,[73] auditioned for dancers for a routine on Top of The Pops (Simon Says by the 1910 Fruitgum Company); two of whom that were successful (Ruth Pearson and Patricia "Dee Dee" Wilde) were part of the existing six-female dance troupe, Pan's People.[74] Like the Go-Jos, this group was also partly drawn from ex-members of the Beat Girls.[75]

Although this routine did not make it onto the programme itself, in subsequent weeks, members of Pan's People (Louise Clarke, Felicity "Flick" Colby, Barbara "Babs" Lord, Pearson, Andrea "Andi" Rutherford and Wilde) started to appear on the programme separately to the Go-Jos. Pan's People were then selected by the BBC over the Go-Jos when they chose a group to be the resident troupe.[76] The Go-Jos' final Top Of The Pops performance was in June 1968 dancing to "Jumping Jack Flash" by The Rolling Stones.

As with the Go-Jos, in the first eighteen months of the Pan's People era the dancers were not a weekly fixture on the programme.[77] However, due to group fan mail and good viewing figures, by 1970 the group was on nearly every week.[78] Pay was not high, they were paid the minimum equity rate of Â£56 per week.[79]

One of the original Pan's People dancers, Colby, became the full-time choreographer in 1971.[80] Colby spoke of the dancing â€“ "They weren't Broadway-standard routines...we were definitely doing watercolours, not oil paintings."[81]

In early 1976, the last remaining of the early members of Pan's People, Ruth Pearson announced her retirement, leaving just four members all of whom who had joined within the last four years; Cherry Gillespie, Mary Corpe, Lee Ward and Sue Menhenick. Rather than continue with this line up or add additional members, it was decided by Colby and BBC production staff to replace this group[82] with a male and female group created for the programme, Ruby Flipper, choreographed by Colby and managed by Colby with Pearson. Lee Ward left shortly after this decision was made, reportedly saying regarding the change "It's a big mistake. Men rush home to watch sexy ladies. They do not want to see other men.".[83]

Rehearsals for this new group started in March 1976, and the group began appearing on Top Of The Pops in May 1976. Whilst producers were aware of the switch to the new group, Bill Cotton, the then head of the light entertainment unit of which Top Of The Pops was part, was not. This group started as a seven-piece with three men (Gavin Trace, Floyd Pearce and Phil Steggles) and four women (Menhenick, Gillespie, Patti Hammond and Lulu Cartwright). Corpe was not invited to join the new troupe. Trace, Pearce, Steggles and Cartwright joined following open auditions, Hammond, an established dancer, was invited to join to complete the "look" following a later individual audition.[84] Colby viewed this gender-mixed group as an opportunity to develop more physical routines including lifts.,[85] more duets and generally not have the whole group at each performance.

However, by August the BBC had decided to terminate the group due to perceived unpopularity and being "... out of step with viewers".[86] Their final appearance was in October 1976.

The group created to replace Ruby Flipper was Legs & Co, reverting to an all-female line-up, and once more choreographed by Colby. Three of the six in the initial line-up (Menhenick, Cartwight and Hammond) were taken from Ruby Flipper.[87] with Rosie Hetherington, Gill Clarke and Pauline Peters making up the six. Despite being an all-female group, on occasion one or more male dancers were brought in, notably Pearce several times.

During their run, the group covered the transition from Disco to Punk, Electronic and Modern Romantic music. Notably, they danced to two Sex Pistols tracks.[88]

By late 1981, Legs & Co (by this time Anita Chellamah had replaced Peters) had become more integrated into the studio audience, rather than performing set-piece routines, as a result of the 'party atmosphere' brought in by Michael Hurll. Also by this time Colby was particularly keen to work once more with male dancers; feeling it time for a change, Legs & Co's stint was ended, and a twenty-member dance troupe (ten male, ten female), named Zoo was created, with a set of performers drawn from the pool of twenty each week.[89] Colby was now credited as "Dance Director".[85] Three members of previous troupes, Menhenick, Corpe and Chellamah, made at least one appearance each during the Zoo period. The dancers now chose their own clothes, moving away from the synchronised appearance of previous troupes.[90]

By the early 1980s, record companies were offering the BBC free promotional videos, meaning dance troupes no longer fulfilled their original purpose.[91] Zoo's run ended in 1983, and with it the use of dance troupes on Top of the Pops.

After the demise of Zoo, the audience took a more active role, often dancing in more prominent areas such as behind performing acts on the back of the stage, and on podiums. However, in addition the show also employed so-called cheerleaders to lead the dancing.

Go-Jos' first performance: 19 November 1964 â€“ Dancing to "Baby Love" by The Supremes[92]

Pan's People first performance (three of the dancers, independently contracted): April 1968 â€“ Dancing to "Young Girl" by Gary Puckett & The Union Gap[93] or "Respect" by Aretha Franklin[94]

Pan's People's first performance (as the six-piece group of early 1968): 30 May 1968 â€“ Dancing to "U.S. Male" by Elvis Presley[94]

Go-Jos' final performance: 27 June 1968 â€“ Dancing to "Jumping Jack Flash" by The Rolling Stones[95]

Pan's People's final performance: 29 April 1976 â€“ Dancing to "Silver Star" by The Four Seasons[96]

Ruby Flipper's first performance: 6 May 1976 â€“ Dancing to "Can't Help Falling In Love" by The Stylistics[97]

Ruby Flipper's final performance: 14 October 1976 â€“ Dancing to "Play That Funky Music" by Wild Cherry

Legs & Co's first performance (credited as Ruby Flipper & Legs & Co): 21 October 1976 â€“ Dancing to "Queen Of My Soul" by Average White Band[89]

Legs & Co's first performance (credited as Legs & Co): 11 November 1976 â€“ Dancing to "Spinning Rock Boogie" by Hank C. Burnette

Legs & Co's final performance: 29 October 1981 â€“ Dancing to "Favourite Shirts (Boy Meets Girl)" by Haircut 100

Zoo's first performance: 5 November 1981 â€“ Dancing to "Twilight" by E.L.O.

Zoo's final performance: 29 September 1983 â€“ Dancing to "What I Got Is What You Need" by Unique

For much of the 1960s the show's theme music was an organ-based instrumental track, also called "Top of the Pops", by the Dave Davani Four.

Due to the BBC's former policy of deleting old programmes, the vast majority of the episodes from the programme's history prior to 1976 have been lost, including the only live appearance by the Beatles.[98]

Of the first 500 episodes (1964–73), only about 20 complete recordings remain in the BBC archives, and the majority of these are from 1969 onwards. The earliest surviving footage dates from 26 February 1964, and consists of performances by Billy J. Kramer and the Dakotas and the Dave Clark Five. Some programmes exist only partially (largely performances that were either pre-recorded or re-used in later editions). There are also two examples of rehearsal footage, which are both from 1965, one which includes Alan Freeman introducing the Seekers,[99] and another with Sandie Shaw rehearsing "Long Live Love"[100]—both believed to be for the end-of-year Christmas Special. There are also cases of shows that only exist in their raw, unedited form. The oldest complete episode in existence was originally transmitted on Boxing Day in 1967 (only four complete recordings from the 1960s survive, two of which have mute presenter links). The most recent that is not held is dated 8 September 1977. Most editions after this date exist in full, except a few 1981-85 episodes recorded live feature mute presenter links (These episodes were skipped on the BBC Four re-runs)

Some off-air recordings, made by fans at home with a microphone in front of the TV speaker, exist in varying quality, including The Jimi Hendrix Experience performing a live version of "Hey Joe" in December 1966.

Some segments of TOTP which have been wiped by the BBC do survive in some form owing to having been included in other programmes, either by the BBC itself or by foreign broadcasters. The only surviving footage of The Beatles on the programme, for instance, comes from its re-use in episode one of 1965 Doctor Who serial The Chase.[101] Additionally a number of recordings are believed to exist in private collections.[102]

The programme was forced off the air for several weeks by industrial action by the Musicians' Union in both 1974 and 1980.

Top of the Pops has a sister show called TOTP2 which uses archive footage from as early as the late 1960s. It began on 17 September 1994. The early series were narrated by Johnnie Walker, before Steve Wright took over as narrator. In summer 2004 BBC Two's controller, Roly Keating, announced that it was being "rested". Shortly after UKTV G2 began showing re-edited versions of earlier programmes with re-recorded dialogue. Finally after a two-year break TOTP2 returned to the BBC Two schedules for a new series on Saturday, 30 September 2006, in an evening timeslot. It was still narrated by Steve Wright and featured a mixture of performances from the TOTP archive and newly recorded performances. The first edition of this series featured new performances by Razorlight and Nelly Furtado recorded after the final episode of Top of the Pops. In 2009 Mark Radcliffe took over as narrator.

Aired on BBC Radio 1 between the mid-1990s and late 2001 was Top of the Pops: The Radio Show which went out every Sunday at 3Â pm just before the singles chart, and was presented by Jayne Middlemiss and Scott Mills. It later reappeared on the BBC World Service in May 2003 originally presented by Emma B, where it continues to be broadcast weekly in an hourly format, now presented by Kim Robson and produced by former BBC World Service producer Alan Rowett.

The defunct channel Play UK created two spin offs; TOTP+ Plus and TOTP@Play (2000–2001) (until mid-2000, this show was called The Phone Zone and was a spin-off from BBC Two music series The O-Zone). BBC Choice featured a show called TOTP The New Chart (5 December 1999 – 26 March 2000) and on BBC Two TOTP+ (8 October 2000 – 26 August 2001) which featured the TOTP @ Play studio and presenters. This is not to be confused with the UK Play version of the same name. A more recent spin-off (now ended) was Top of the Pops Saturday hosted originally by Fearne Cotton and Simon Grant, and its successor Top of the Pops Reloaded. This was shown on Saturday mornings on BBC One and featured competitions, star interviews, video reviews and some Top of the Pops performances. This was aimed at a younger audience and was part of the CBBC Saturday morning line-up. This was to rival CD:UK at the same time on ITV.

A number of performers have sent up the format in various ways. Mainly this has been performers who disliked the mime format of the show, often as a more effective protest against this rather than just refusing to appear.

The TOTP format was sold to RTL in Germany in the 1990s, and aired on Saturday afternoons. It was very successful for a long time, with a compilation album series and magazine. However, in 2006 it was announced that the German show would be ending. The Italian version (first broadcast on Rai 2 and later on Italia 1) also ended in 2006. In February 2010 the show returned on Rai 2, and was broadcast for two seasons before being cancelled again in October 2011. The French version of the show ended by September 2006. The Dutch version of the show continued to run on BNN until the end of December 2006.[110] BBC Prime used to broadcast re-edited episodes of the BBC version, the weekend after it was transmitted in the UK. Ireland began transmitting Top of the Pops in November 1978 on RTÉ2. This was the UK version being transmitted at the same time as on BBC. The broadcasts ceased in late 1993.

Top of the Pops had short-lived fame in the United States. In 1987, the CBS television network decided to try an American version of the show. It was hosted by Nia Peeples and even showed performances from the BBC version of the programme. The show was presented on late Friday nights as part of CBS Late Night, and lasted almost a year.

In 2002, BBC America presented the BBC version of Top of the Pops as part of their weekend schedule. The network would get the episodes one week after they were transmitted in the UK. BBC America then tinkered with the show by cutting a few minutes out of each show and moving it to a weekday time slot.

On 23 January 2006, Lou Pearlman made a deal to bring Top of the Pops back to the airwaves in the United States. It was expected to be similar to the 1987 version, but it would also utilise the Billboard magazine music charts, most notably the Hot 100 chart. It was supposed to be planned for a possible 2006 or 2007 launch, but with several lawsuits against Lou and his companies (which resulted in his conviction in 2008), as well as the cancellation of the UK version, the proposed US project never went forward. On 19 August 2006, VH1 aired the UK series' final episode.

The United States had its own similar series, American Bandstand, which aired nationally on ABC from 1957 to 1987 (although it would continue in first-run syndication until 1988 and end its run on USA in 1989). Similar series also included Soul Train (1970–2006, featuring R&B artists), Club MTV (1986–92, featuring Dance Music acts; hosted by Downtown Julie Brown, an alumnus of TOTP as part of the show's last dance troupe Zoo) and Solid Gold (1980–88; like the early TOTP, it also used dance troupes).

Canada's version of this (mostly of American Bandstand and Soul Train) was Electric Circus (1988â€“2003) on MuchMusic, which was also seen in the USA through MuchMusic USA. It had a national chart (mostly of dance music and some pop) as well as live performances, and was based on a local late '70s programme in Toronto called CITY-TV Boogie.

The Top of the Pops brand has also been exported to New Zealand which for many years had to rely on music-video only shows to demonstrate its Top 20 (as well as the occasional season of the UK version of TOTP) as the world's top acts found New Zealand just too far away from the major markets to visit regularly. This all changed in 2002 when the New Zealand government suggested a voluntary New Zealand music quota on radio[111] (basically a threat that if the stations did not impose a quota themselves then one would be imposed on them). This worked and suddenly the amount of indigenous music played on radio stations increased, as did the number of New Zealand hits in the top 20. Therefore, a new version of a show like Top of the Pops became feasible for the first time, and the show was commissioned by Television New Zealand. The show was Executive Produced by David Rose, managing director and owner of Satellite Media and began in early 2004 with host Alex Behan. The hour-long show (as opposed to the 30-minute UK version) which is broadcast at 5Â pm on Saturdays on TV2 (New Zealand) contains a mixture of songs recorded on a sound stage in the Auckland CBD, as well as performances from the international versions of the show. The New Zealand Top 20 singles and Top 10 albums are also featured. Alex stayed as host for two years before Bede Skinner took over. Despite a popular fan base in early 2006 TVNZ announced that Top of the Pops has been axed and ideas for new music shows are currently being considered.

Free-to-air music channel C4 then picked up the UK version of 'Top of the Pops and aired it on Saturdays at 8Â pm with a repeat screening on Thursdays. However, since the weekly UK version was axed itself, this arrangement also ended.

An edited version of the UK show was shown on BBC Prime, the weekend after UK transmission.

In addition, a licensed version was shown on the United Arab Emirates-based MBC 2 television channel. This version consisted of parts of the UK version, including the Top 10 charts, as well as live performances by Arabic pop singers.

A complete version of the UK show was shown on People+Arts, two weeks after the UK transmission.

A number of compilation albums using the Top of the Pops brand have been issued over the years. The first one to reach the charts was BBC TV's The Best of Top of the Pops on the Super Beeb record label in 1975, which reached number 21.

Starting in 1968 and carrying on through the 1970s a rival series of Top of the Pops albums were produced, however these had no connection with the television series except for its name. They were a series of budget cover albums of current chart hits recorded by anonymous session singers and musicians released on the Hallmark record label. They had initially reached the charts but were later disallowed due to a change in the criteria for entering the charts. These albums continued to be produced until the early 1980s, when the advent of compilation albums featuring the original versions of hits, such as the Now That's What I Call Music! series, led to a steep decline in their popularity.

In the 1990s, the BBC Top of the Pops brand was again licensed for use in a tie-in compilation series. Starting in 1995 with Sony Music's Columbia Records label, these double disc collections moved to the special marketing arm of PolyGram / Universal Music Group TV, before becoming a sister brand of the Now That's What I Call Music! range in the EMI / Virgin / Universal joint venture.

Similarly to the roles of Top of the Pops on BBC One and BBC Two in the late 1990s and early 2000s, the compilation albums range featured current hits for the main series and classic hits (such as '70s Rock) for the "Top of the Pops 2" spin-offs.

The Top of the Pops brand has now been licensed by EMI who released a compilation series in 2007â€“08, with one CD for each year that Top of the Pops was running. The boxset for the entire series of 43 discs was released 7 July 2008. A podcast supporting the release of the boxset featuring interviews with Mark Goodier, Miles Leonard, Malcolm McLaren and David Hepworth is available.

These albums in the series reached No. 1:

Top of the Pops magazine has been running since February 1995, and filled the void in the BBC magazine portfolio where Number One magazine used to be. It began much in the mould of Q magazine, then changed its editorial policy to directly compete with popular teen celebrity magazines such as Smash Hits and Big, with free sticker giveaways replacing Brett Anderson covers.

A July 1996 feature on the Spice Girls coined the famous "Spice" nicknames for each member (Baby, Ginger, Posh, Scary and Sporty) that stayed with them throughout their career as a group and beyond.[112]

The BBC announced that the magazine would continue in publication despite the end of the television series, and is still running.

An earlier Top of the Pops magazine appeared briefly in the mid-1970s. Mud drummer Dave Mount sat reading an edition throughout a 1975 appearance on the show.

In May 2006, following a special Red Hot Chili Peppers concert recorded in the car park of BBC Television Centre, Hammersmith and Fulham Council (which governs the area the centre is located) informed the BBC that in order to legally conform to an Act of Parliament which came into force in 2004 they needed to have a special licence to continue to admit members of the public to any future performances. Before the matter was resolved the BBC requested the assistance of their own staff members to fill-in as audience members for this and other music shows.[114]

In 2004 there was a DVD released called Top of the Pops 40th Anniversary 1964–2004 DVD. It features live performances, containing one song for each year, except 1966. (Two tracks from 1965 are featured instead). Also included as extras are seven opening titles, most notably the one with the flying coloured LP's from 1981. This title sequence had Phil Lynott's song "Yellow Pearl" as the theme. The 1986 and 1989 titles are also featured, with Paul Hardcastle's hit "The Wizard" as the theme. This DVD was to celebrate 40 years since the show started.

There was also a DVD quiz released in 2007 called The Essential Music Quiz. There was also a DVD in 2001 called Summer 2001, a sister DVD to the album of the same name.


what term defines the nonliving components of an ecosystem such as climate water and soil

Energy, water, nitrogen and soil minerals are other essential abiotic components of an ecosystem. The energy that flows through ecosystems is obtained primarily from the sun. It generally enters the system through photosynthesis, a process that also captures carbon dioxide from the atmosphere. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.[8]

Ecosystem

An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment (things like air, water and mineral soil), interacting as a system.[2] These biotic and abiotic components are regarded as linked together through nutrient cycles and energy flows.[3] As ecosystems are defined by the network of interactions among organisms, and between organisms and their environment,[4] they can be of any size but usually encompass specific, limited spaces[5] (although some scientists say that the entire planet is an ecosystem).[6] An ecosystem is all the living and nonliving things in a certain area. All the plants and animals, even the microorganisms that live in the soil, are living parts of an ecosystem. Air, water, and rocks are nonliving parts of an ecosystem. It can be said to be a biological community of interacting organisms and their physical environment. An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere). Ecosystems are the foundations of the Biosphere and they determine the health of the entire earth system.[7]

Ecosystems are controlled both by external and internal factors. External factors such as climate, the parent material that forms the soil, and topography control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem.[9] Other external factors include time and potential biota. Ecosystems are dynamic entitiesâ€”invariably, they are subject to periodic disturbances and are in the process of recovering from some past disturbance.[10] Ecosystems in similar environments that are located in different parts of the world can have very different characteristics simply because they contain different species.[9] The introduction of non-native species can cause substantial shifts in ecosystem function. Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops.[9] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[9] Other internal factors include disturbance, succession and the types of species present. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[9]

Biodiversity affects ecosystem function, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend; the principles of ecosystem management suggest that rather than managing individual species, natural resources should be managed at the level of the ecosystem itself. Classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management, but there is no single, agreed-upon way to do this.

The term "ecosystem" was first used in 1935 in a publication by British ecologist Arthur Tansley.[fn 1][11] Tansley devised the concept to draw attention to the importance of transfers of materials between organisms and their environment.[12] He later refined the term, describing it as "The whole system,... including not only the organism-complex, but also the whole complex of physical factors forming what we call the environment".[13] Tansley regarded ecosystems not simply as natural units, but as mental isolates.[13] Tansley later[14] defined the spatial extent of ecosystems using the term ecotope.

G. Evelyn Hutchinson, a pioneering limnologist who was a contemporary of Tansley's, combined Charles Elton's ideas about trophic ecology with those of Russian geochemist Vladimir Vernadsky to suggest that mineral nutrient availability in a lake limited algal production which would, in turn, limit the abundance of animals that feed on algae. Raymond Lindeman took these ideas one step further to suggest that the flow of energy through a lake was the primary driver of the ecosystem. Hutchinson's students, brothers Howard T. Odum and Eugene P. Odum, further developed a "systems approach" to the study of ecosystems, allowing them to study the flow of energy and material through ecological systems.[12]

Energy and carbon enter ecosystems through photosynthesis, are incorporated into living tissue, transferred to other organisms that feed on the living and dead plant matter, and eventually released through respiration.[15] Most mineral nutrients, on the other hand, are recycled within ecosystems.[16]

Ecosystems are controlled both by external and internal factors. External factors, also called state factors, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. The most important of these is climate.[9] Climate determines the biome in which the ecosystem is embedded. Rainfall patterns and temperature seasonality determine the amount of water available to the ecosystem and the supply of energy available (by influencing photosynthesis).[9] Parent material, the underlying geological material that gives rise to soils, determines the nature of the soils present, and influences the supply of mineral nutrients. Topography also controls ecosystem processes by affecting things like microclimate, soil development and the movement of water through a system. This may be the difference between the ecosystem present in wetland situated in a small depression on the landscape, and one present on an adjacent steep hillside.[9]

Other external factors that play an important role in ecosystem functioning include time and potential biota. Ecosystems are dynamic entitiesâ€”invariably, they are subject to periodic disturbances and are in the process of recovering from some past disturbance.[10] Time plays a role in the development of soil from bare rock and the recovery of a community from disturbance.[9] Similarly, the set of organisms that can potentially be present in an area can also have a major impact on ecosystems. Ecosystems in similar environments that are located in different parts of the world can end up doing things very differently simply because they have different pools of species present.[9] The introduction of non-native species can cause substantial shifts in ecosystem function.

Unlike external factors, internal factors in ecosystems not only control ecosystem processes, but are also controlled by them. Consequently, they are often subject to feedback loops.[9] While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading.[9] Other factors like disturbance, succession or the types of species present are also internal factors. Human activities are important in almost all ecosystems. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.[9]

Primary production is the production of organic matter from inorganic carbon sources. Overwhelmingly, this occurs through photosynthesis. The energy incorporated through this process supports life on earth, while the carbon makes up much of the organic matter in living and dead biomass, soil carbon and fossil fuels. It also drives the carbon cycle, which influences global climate via the greenhouse effect.

Through the process of photosynthesis, plants capture energy from light and use it to combine carbon dioxide and water to produce carbohydrates and oxygen. The photosynthesis carried out by all the plants in an ecosystem is called the gross primary production (GPP).[17] About 48â€“60% of the GPP is consumed in plant respiration. The remainder, that portion of GPP that is not used up by respiration, is known as the net primary production (NPP).[15] Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.[17]

The carbon and energy incorporated into plant tissues (net primary production) is either consumed by animals while the plant is alive, or it remains uneaten when the plant tissue dies and becomes detritus. In terrestrial ecosystems, roughly 90% of the NPP ends up being broken down by decomposers. The remainder is either consumed by animals while still alive and enters the plant-based trophic system, or it is consumed after it has died, and enters the detritus-based trophic system. In aquatic systems, the proportion of plant biomass that gets consumed by herbivores is much higher.[19] In trophic systems photosynthetic organisms are the primary producers. The organisms that consume their tissues are called primary consumers or secondary producers—herbivores. Organisms which feed on microbes (bacteria and fungi) are termed microbivores. Animals that feed on primary consumers—carnivores—are secondary consumers. Each of these constitutes a trophic level.[19] The sequence of consumption—from plant to herbivore, to carnivore—forms a food chain. Real systems are much more complex than this—organisms will generally feed on more than one form of food, and may feed at more than one trophic level. Carnivores may capture some prey which are part of a plant-based trophic system and others that are part of a detritus-based trophic system (a bird that feeds both on herbivorous grasshoppers and earthworms, which consume detritus). Real systems, with all these complexities, form food webs rather than food chains.[19]

The carbon and nutrients in dead organic matter are broken down by a group of processes known as decomposition. This releases nutrients that can then be re-used for plant and microbial production, and returns carbon dioxide to the atmosphere (or water) where it can be used for photosynthesis. In the absence of decomposition, dead organic matter would accumulate in an ecosystem and nutrients and atmospheric carbon dioxide would be depleted.[20] Approximately 90% of terrestrial NPP goes directly from plant to decomposer.[19]

Decomposition processes can be separated into three categoriesâ€”leaching, fragmentation and chemical alteration of dead material. As water moves through dead organic matter, it dissolves and carries with it the water-soluble components. These are then taken up by organisms in the soil, react with mineral soil, or are transported beyond the confines of the ecosystem (and are considered "lost" to it).[20] Newly shed leaves and newly dead animals have high concentrations of water-soluble components, and include sugars, amino acids and mineral nutrients. Leaching is more important in wet environments, and much less important in dry ones.[20]

Fragmentation processes break organic material into smaller pieces, exposing new surfaces for colonization by microbes. Freshly shed leaf litter may be inaccessible due to an outer layer of cuticle or bark, and cell contents are protected by a cell wall. Newly dead animals may be covered by an exoskeleton. Fragmentation processes, which break through these protective layers, accelerate the rate of microbial decomposition.[20] Animals fragment detritus as they hunt for food, as does passage through the gut. Freeze-thaw cycles and cycles of wetting and drying also fragment dead material.[20]

The chemical alteration of dead organic matter is primarily achieved through bacterial and fungal action. Fungal hyphae produce enzymes which can break through the tough outer structures surrounding dead plant material. They also produce enzymes which break down lignin, which allows to them access to both cell contents and to the nitrogen in the lignin. Fungi can transfer carbon and nitrogen through their hyphal networks and thus, unlike bacteria, are not dependent solely on locally available resources.[20]

Decomposition rates vary among ecosystems. The rate of decomposition is governed by three sets of factors—the physical environment (temperature, moisture and soil properties), the quantity and quality of the dead material available to decomposers, and the nature of the microbial community itself.[21] Temperature controls the rate of microbial respiration; the higher the temperature, the faster microbial decomposition occurs. It also affects soil moisture, which slows microbial growth and reduces leaching. Freeze-thaw cycles also affect decomposition—freezing temperatures kill soil microorganisms, which allows leaching to play a more important role in moving nutrients around. This can be especially important as the soil thaws in the Spring, creating a pulse of nutrients which become available.[21]

Decomposition rates are low under very wet or very dry conditions. Decomposition rates are highest in wet, moist conditions with adequate levels of oxygen. Wet soils tend to become deficient in oxygen (this is especially true in wetlands), which slows microbial growth. In dry soils, decomposition slows as well, but bacteria continue to grow (albeit at a slower rate) even after soils become too dry to support plant growth. When the rains return and soils become wet, the osmotic gradient between the bacterial cells and the soil water causes the cells to gain water quickly. Under these conditions, many bacterial cells burst, releasing a pulse of nutrients.[21] Decomposition rates also tend to be slower in acidic soils.[21] Soils which are rich in clay minerals tend to have lower decomposition rates, and thus, higher levels of organic matter.[21] The smaller particles of clay result in a larger surface area that can hold water. The higher the water content of a soil, the lower the oxygen content[22] and consequently, the lower the rate of decomposition. Clay minerals also bind particles of organic material to their surface, making them less accessibly to microbes.[21] Soil disturbance like tilling increase decomposition by increasing the amount of oxygen in the soil and by exposing new organic matter to soil microbes.[21]

The quality and quantity of the material available to decomposers is another major factor that influences the rate of decomposition. Substances like sugars and amino acids decompose readily and are considered "labile". Cellulose and hemicellulose, which are broken down more slowly, are "moderately labile". Compounds which are more resistant to decay, like lignin or cutin, are considered "recalcitrant".[21] Litter with a higher proportion of labile compounds decomposes much more rapidly than does litter with a higher proportion of recalcitrant material. Consequently, dead animals decompose more rapidly than dead leaves, which themselves decompose more rapidly than fallen branches.[21] As organic material in the soil ages, its quality decreases. The more labile compounds decompose quickly, leaving an increasing proportion of recalcitrant material. Microbial cell walls also contain recalcitrant materials like chitin, and these also accumulate as the microbes die, further reducing the quality of older soil organic matter.[21]

Ecosystems continually exchange energy and carbon with the wider environment; mineral nutrients, on the other hand, are mostly cycled back and forth between plants, animals, microbes and the soil. Most nitrogen enters ecosystems through biological nitrogen fixation, is deposited through precipitation, dust, gases or is applied as fertilizer.[16] Since most terrestrial ecosystems are nitrogen-limited, nitrogen cycling is an important control on ecosystem production.[16]

Until modern times, nitrogen fixation was the major source of nitrogen for ecosystems. Nitrogen fixing bacteria either live symbiotically with plants, or live freely in the soil. The energetic cost is high for plants which support nitrogen-fixing symbiontsâ€”as much as 25% of GPP when measured in controlled conditions. Many members of the legume plant family support nitrogen-fixing symbionts. Some cyanobacteria are also capable of nitrogen fixation. These are phototrophs, which carry out photosynthesis. Like other nitrogen-fixing bacteria, they can either be free-living or have symbiotic relationships with plants.[16] Other sources of nitrogen include acid deposition produced through the combustion of fossil fuels, ammonia gas which evaporates from agricultural fields which have had fertilizers applied to them, and dust.[16] Anthropogenic nitrogen inputs account for about 80% of all nitrogen fluxes in ecosystems.[16]

When plant tissues are shed or are eaten, the nitrogen in those tissues becomes available to animals and microbes. Microbial decomposition releases nitrogen compounds from dead organic matter in the soil, where plants, fungi and bacteria compete for it. Some soil bacteria use organic nitrogen-containing compounds as a source of carbon, and release ammonium ions into the soil. This process is known as nitrogen mineralization. Others convert ammonium to nitrite and nitrate ions, a process known as nitrification. Nitric oxide and nitrous oxide are also produced during nitrification.[16] Under nitrogen-rich and oxygen-poor conditions, nitrates and nitrites are converted to nitrogen gas, a process known as denitrification.[16]

Other important nutrients include phosphorus, sulfur, calcium, potassium, magnesium and manganese.[23] Phosphorus enters ecosystems through weathering. As ecosystems age this supply diminishes, making phosphorus-limitation more common in older landscapes (especially in the tropics).[23] Calcium and sulfur are also produced by weathering, but acid deposition is an important source of sulfur in many ecosystems. Although magnesium and manganese are produced by weathering, exchanges between soil organic matter and living cells account for a significant portion of ecosystem fluxes. Potassium is primarily cycled between living cells and soil organic matter.[23]

Ecosystem processes are broad generalizations that actually take place through the actions of individual organisms. The nature of the organisms—the species, functional groups and trophic levels to which they belong—dictates the sorts of actions these individuals are capable of carrying out, and the relative efficiency with which they do so. Thus, ecosystem processes are driven by the number of species in an ecosystem, the exact nature of each individual species, and the relative abundance organisms within these species.[25] Biodiversity plays an important role in ecosystem functioning.[26]

Ecological theory suggests that in order to coexist, species must have some level of limiting similarity—they must be different from one another in some fundamental way, otherwise one species would competitively exclude the other.[27] Despite this, the cumulative effect of additional species in an ecosystem is not linear—additional species may enhance nitrogen retention, for example, but beyond some level of species richness, additional species may have little additive effect.[25] The addition (or loss) of species which are ecologically similar to those already present in an ecosystem tends to only have a small effect on ecosystem function. Ecologically distinct species, on the other hand, have a much larger effect. Similarly, dominant species have a large impact on ecosystem function, while rare species tend to have a small effect. Keystone species tend to have an effect on ecosystem function that is disproportionate to their abundance in an ecosystem.[25]

Ecosystems provide a variety of goods and services upon which people depend.[28] Ecosystem goods include the "tangible, material products"[29] of ecosystem processes—food, construction material, medicinal plants—in addition to less tangible items like tourism and recreation, and genes from wild plants and animals that can be used to improve domestic species.[28] Ecosystem services, on the other hand, are generally "improvements in the condition or location of things of value".[29] These include things like the maintenance of hydrological cycles, cleaning air and water, the maintenance of oxygen in the atmosphere, crop pollination and even things like beauty, inspiration and opportunities for research.[28] While ecosystem goods have traditionally been recognized as being the basis for things of economic value, ecosystem services tend to be taken for granted.[29] While Gretchen Daily's original definition distinguished between ecosystem goods and ecosystem services, Robert Costanza and colleagues' later work and that of the Millennium Ecosystem Assessment lumped all of these together as ecosystem services.[29][30]

When natural resource management is applied to whole ecosystems, rather than single species, it is termed ecosystem management.[31] A variety of definitions exist: F. Stuart Chapin and coauthors define it as "the application of ecological science to resource management to promote long-term sustainability of ecosystems and the delivery of essential ecosystem goods and services",[32] while Norman Christensen and coauthors defined it as "management driven by explicit goals, executed by policies, protocols, and practices, and made adaptable by monitoring and research based on our best understanding of the ecological interactions and processes necessary to sustain ecosystem structure and function"[28] and Peter Brussard and colleagues defined it as "managing areas at various scales in such a way that ecosystem services and biological resources are preserved while appropriate human use and options for livelihood are sustained".[33]

Although definitions of ecosystem management abound, there is a common set of principles which underlie these definitions.[32] A fundamental principle is the long-term sustainability of the production of goods and services by the ecosystem;[32] "intergenerational sustainability [is] a precondition for management, not an afterthought".[28] It also requires clear goals with respect to future trajectories and behaviors of the system being managed. Other important requirements include a sound ecological understanding of the system, including connectedness, ecological dynamics and the context in which the system is embedded. Other important principles include an understanding of the role of humans as components of the ecosystems and the use of adaptive management.[28] While ecosystem management can be used as part of a plan for wilderness conservation, it can also be used in intensively managed ecosystems[28] (see, for example, agroecosystem and close to nature forestry).

Ecosystems are dynamic entitiesâ€”invariably, they are subject to periodic disturbances and are in the process of recovering from some past disturbance.[10] When an ecosystem is subject to some sort of perturbation, it responds by moving away from its initial state. The tendency of a system to remain close to its equilibrium state, despite that disturbance, is termed its resistance. On the other hand, the speed with which it returns to its initial state after disturbance is called its resilience.[10]

From one year to another, ecosystems experience variation in their biotic and abiotic environments. A drought, an especially cold winter and a pest outbreak all constitute short-term variability in environmental conditions. Animal populations vary from year to year, building up during resource-rich periods and crashing as they overshoot their food supply. These changes play out in changes in NPP, decomposition rates, and other ecosystem processes.[10] Longer-term changes also shape ecosystem processesâ€”the forests of eastern North America still show legacies of cultivation which ceased 200 years ago, while methane production in eastern Siberian lakes is controlled by organic matter which accumulated during the Pleistocene.[10]

Disturbance also plays an important role in ecological processes. F. Stuart Chapin and coauthors define disturbance as "a relatively discrete event in time and space that alters the structure of populations, communities and ecosystems and causes changes in resources availability or the physical environment".[34] This can range from tree falls and insect outbreaks to hurricanes and wildfires to volcanic eruptions and can cause large changes in plant, animal and microbe populations, as well soil organic matter content.[10] Disturbance is followed by succession, a "directional change in ecosystem structure and functioning resulting from biotically driven changes in resources supply."[34]

The frequency and severity of disturbance determines the way it impacts ecosystem function. Major disturbance like a volcanic eruption or glacial advance and retreat leave behind soils that lack plants, animals or organic matter. Ecosystems that experience disturbances that undergo primary succession. Less severe disturbance like forest fires, hurricanes or cultivation result in secondary succession.[10] More severe disturbance and more frequent disturbance result in longer recovery times. Ecosystems recover more quickly from less severe disturbance events.[10]

The early stages of primary succession are dominated by species with small propagules (seed and spores) which can be dispersed long distances. The early colonizers—often algae, cyanobacteria and lichens—stabilize the substrate. Nitrogen supplies are limited in new soils, and nitrogen-fixing species tend to play an important role early in primary succession. Unlike in primary succession, the species that dominate secondary succession, are usually present from the start of the process, often in the soil seed bank. In some systems the successional pathways are fairly consistent, and thus, are easy to predict. In others, there are many possible pathways—for example, the introduced nitrogen-fixing legume, Myrica faya, alter successional trajectories in Hawaiian forests.[10]

The theoretical ecologist Robert Ulanowicz has used information theory tools to describe the structure of ecosystems, emphasizing mutual information (correlations) in studied systems. Drawing on this methodology and prior observations of complex ecosystems, Ulanowicz depicts approaches to determining the stress levels on ecosystems and predicting system reactions to defined types of alteration in their settings (such as increased or reduced energy flow, and eutrophication.[35]

Ecosystem ecology studies "the flow of energy and materials through organisms and the physical environment". It seeks to understand the processes which govern the stocks of material and energy in ecosystems, and the flow of matter and energy through them. The study of ecosystems can cover 10 orders of magnitude, from the surface layers of rocks to the surface of the planet.[36]

There is no single definition of what constitutes an ecosystem.[37] German ecologist Ernst-Detlef Schulze and coauthors defined an ecosystem as an area which is "uniform regarding the biological turnover, and contains all the fluxes above and below the ground area under consideration." They explicitly reject Gene Likens' use of entire river catchments as "too wide a demarcation" to be a single ecosystem, given the level of heterogeneity within such an area.[38] Other authors have suggested that an ecosystem can encompass a much larger area, even the whole planet.[6] Schulze and coauthors also rejected the idea that a single rotting log could be studied as an ecosystem because the size of the flows between the log and its surroundings are too large, relative to the proportion cycles within the log.[38] Philosopher of science Mark Sagoff considers the failure to define "the kind of object it studies" to be an obstacle to the development of theory in ecosystem ecology.[37]

Ecosystems can be studied through a variety of approachesâ€”theoretical studies, studies monitoring specific ecosystems over long periods of time, those that look at differences between ecosystems to elucidate how they work and direct manipulative experimentation.[39] Studies can be carried out at a variety of scales, from microcosms and mesocosms which serve as simplified representations of ecosystems, through whole-ecosystem studies.[40] American ecologist Stephen R. Carpenter has argued that microcosm experiments can be "irrelevant and diversionary" if they are not carried out in conjunction with field studies carried out at the ecosystem scale, because microcosm experiments often fail to accurately predict ecosystem-level dynamics.[41]

The Hubbard Brook Ecosystem Study, established in the White Mountains, New Hampshire in 1963, was the first successful attempt to study an entire watershed as an ecosystem. The study used stream chemistry as a means of monitoring ecosystem properties, and developed a detailed biogeochemical model of the ecosystem.[42] Long-term research at the site led to the discovery of acid rain in North America in 1972, and was able to document the consequent depletion of soil cations (especially calcium) over the next several decades.[43]

Classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management.[44] A variety of systems exist, based on vegetation cover, remote sensing, and bioclimatic classification systems.[44] American geographer Robert Bailey defines a hierarchy of ecosystem units ranging from microecosystems (individual homogeneous sites, on the order of 10 square kilometres (4 sq mi) in area), through mesoecosystems (landscape mosaics, on the order of 1,000 square kilometres (400 sq mi)) to macroecosystems (ecoregions, on the order of 100,000 square kilometres (40,000 sq mi)).[45]

Bailey outlined five different methods for identifying ecosystems: gestalt ("a whole that is not derived through considerable of its parts"), in which regions are recognized and boundaries drawn intuitively; a map overlay system where different layers like geology, landforms and soil types are overlain to identify ecosystems; multivariate clustering of site attributes; digital image processing of remotely sensed data grouping areas based on their appearance or other spectral properties; or by a "controlling factors method" where a subset of factors (like soils, climate, vegetation physiognomy or the distribution of plant or animal species) are selected from a large array of possible ones are used to delineate ecosystems.[46] In contrast with Bailey's methodology, Puerto Rico ecologist Ariel Lugo and coauthors identified ten characteristics of an effective classification system: that it be based on georeferenced, quantitative data; that it should minimize subjectivity and explicitly identify criteria and assumptions; that it should be structured around the factors that drive ecosystem processes; that it should reflect the hierarchical nature of ecosystems; that it should be flexible enough to conform to the various scales at which ecosystem management operates; that it should be tied to reliable measures of climate so that it can "anticipat[e] global climate change; that it be applicable worldwide; that it should be validated against independent data; that it take into account the sometimes complex relationship between climate, vegetation and ecosystem functioning; and that it should be able to adapt and improve as new data become available".[44]

As human populations and per capita consumption grow, so do the resource demands imposed on ecosystems and the impacts of the human ecological footprint. Natural resources are not invulnerable and infinitely available. The environmental impacts of anthropogenic actions, which are processes or materials derived from human activities, are becoming more apparent—air and water quality are increasingly compromised, oceans are being overfished, pests and diseases are extending beyond their historical boundaries, and deforestation is exacerbating flooding downstream. It has been reported that approximately 40–50% of Earth's ice-free land surface has been heavily transformed or degraded by anthropogenic activities, 66% of marine fisheries are either overexploited or at their limit, atmospheric CO2 has increased more than 30% since the advent of industrialization, and nearly 25% of Earth's bird species have gone extinct in the last two thousand years.[47] Society is increasingly becoming aware that ecosystem services are not only limited, but also that they are threatened by human activities. The need to better consider long-term ecosystem health and its role in enabling human habitation and economic activity is urgent. To help inform decision-makers, many ecosystem services are being assigned economic values, often based on the cost of replacement with anthropogenic alternatives. The ongoing challenge of prescribing economic value to nature, for example through biodiversity banking, is prompting transdisciplinary shifts in how we recognize and manage the environment, social responsibility, business opportunities, and our future as a species.