By the 1970s it became increasingly obvious that widespread biodiversity loss and significant habitat damage was occurring in the wider countryside, further compounded by the impacts of the Common Agricultural Policy after 1973.
The Nature Conservancy Council highlighted the erosion of the SSSIs, forcing a reappraisal of policies for nature conservation and eventually new legislation, the Wildlife & Countryside Act (1981).
Another significant impact to our landscape was a new epidemic of Dutch elm disease (caused by fungi originally from Asia) which took hold in the mid-1970s and effectively wiping out most of the British elms by the early 1980s.
The 1970s witnessed a growing reaction from local communities against real - or perceived - discriminations and injustices. Green politics, dominated by nuclear concerns, emerged, and were often expressed in establishing community gardens and spaces, especially in sites that had long lain derelict.
This took particular root in respect of cemeteries, many of which had become too costly to maintain in their original condition and had become overgrown.
New groups campaigned for and took on aspects of their management - for example Friends of Highgate Cemetery (1975) and Friends of Nunhead Cemetery (1977) - and identifying the benefit these cemeteries for wildlife.
At the same time, in the Black Country, the foundations of urban nature conservation began, in response to the lack of focus being given to the wildlife of our towns and cities by the government agencies and nature conservation organisations.
Voices of those post-industrial advocates such as Nan Fairbrother, Richard Mabey, George Barker and Chris Baines began to be translated into action.
In 1974 Perivale Wood became London's first statutory Local Nature Reserve, and the following year a further 12 Sites of Special Scientific Interest were notified in London, including Abbey Wood, Riddlesdown, and Walthamstow Reservoirs.
In 1976 the Ecological Parks Trust was founded by Max Nicholson, and established the William Curtis Ecological Park by Tower Bridge. Within a few years local wildlife groups in London came together to form the London Wildlife Trust in 1981.
Towards a greener - and wilder? - city
London at the turn of the 1980s was at a threshold; a new Conservative government was keen to trigger economic growth through regeneration, and yet the voices for environmental protection were gaining confidence.
Large areas of moribund industrial sites lay derelict, nowhere more than in docklands. The London Docklands Development Corporation facilitated the regeneration of the Surrey Docks and those around Isle of Dogs, leading to a new thrusting economic centre around Canary Wharf by the mid-1990s.
The GLC established an Ecology Team from 1982, and in 1984 commissioned London Wildlife Trust to undertake the London Wildlife Habitat Survey, the first of its kind in a city.
A team surveyed accessible green spaces of greater than 0.5 hectares, and discovered new species to London and many new potential wildlife sites in the process.
This audit, subsequently updated in most boroughs, helped to provide the foundations of the wildlife site system in London from 1986, that is still in use today (with 1507 Sites of Importance for Nature Conservation in 2011).
By that time two landmark actions had also taken place: Gunnersbury Triangle in Chiswick was saved from development on the recognition of its local nature interest; and Camley Street Natural Park had become established at Kings Cross, after a campaign and collaboration between the GLC, London Wildlife Trust and local people.
The GLC started to develop policies to embed nature conservation in the Boroughs' local plans, but the battle between its leader, Ken Livingstone, and government led to its abolition in 1986, the first time London had been without city-wide governance since 1889.
The work of the Ecology Team continued through the London Ecology Unit which built on the work of the habitat surveys, providing advice for boroughs and working with London Wildlife Trust, English Nature and the Countryside Commission to further embed a policy framework in London planning which remains largely in place to today.
London Wildlife Trust started taking on the management of nature reserves, and campaigning against a range of proposals that threatened to damage at Rainham Marshes, Sydenham Hill Wood, and Oxleas Wood, amongst others.
Road-building programmes, regeneration schemes and - from 1989 - the Channel Tunnel Rail-link required vigilance and action to prevent them damaging wildlife sites.
On a positive side, however, London boroughs began employing ecologists (Lewisham, reputedly, being the first) and rangers, that helped to change the ways parks were managed and engage the public in the natural world.
The number of nature reserves in London began to markedly increase from the late 1980s.
In October 1987 a hurricane swept across southern England, causing widespread damage and felling 15 million trees.
In the longer-term the Great Storm was probably beneficial to the ecology of many woodlands. Nevertheless, the alarm at the scale of the immediate damage (often made worse ecologically by much of the clear-up), and a markedly changed landscape led to government action.
Taskforce Trees was established, re-invigorating a tree-planting programme, and initiating 12 Community Forests, two of which included parts of London (Thames Chase and Watling Chase) and thereby bringing the Forestry Commission’s interest into the capital.
In January 1990 the Burns' Day Storm wrought further damage and life-loss across London and the south east. It was also at about this time that the decline in London's population since 1939 reversed; about 6.8 million people were now living in Greater London.
Following the Rio Convention on Biological Diversity in 1992, the Biodiversity Action Planning process began, arguably leading to a different framework for nature conservation.
In 1996 the London Biodiversity Partnership formed, which has since overseen and helped deliver action plans for a suite of habitats and species, both at a London and a borough level.
A number of these in London have triggered innovative practice in respect of parks management, sustainable urban drainage, and the development of a green roof renaissance in Britain in the first decade of the 21st century.