A fifth of England's distinctive rural landscapes are showing signs of neglect, the first audit of the country's natural environment has found

Woodlands in particular need new protection measures, says the report released today by Natural England.

Lack of woodland management is partly responsible for a 50 per cent decline in native woodland butterflies and only 3 per cent of grassland remains rich in native plants.

The traditional threat to the environment and wildlife has come from development and intensive farming but climate change is now highlighted as a significant factor. It is affecting the coast where habitats are being squeezed between sea walls and the rising sea - for example, there is a 25 per cent loss of salt marsh in the South East — and on land, where various species such as the mountain ringlet butterfly are moving northwards in search of cooler temperatures.

Helen Phillips, chief executive of Natural England, says that without a new approach to conservation “there's a real danger that some of our most precious wildlife will be lost for ever and our lives will be poorer for it”.

Natural England wants more people to benefit from green spaces — from mountains to moors, countryside walks and green belt land on the fringes of towns and suburbs. The agency is convinced that a healthy environment is linked to the health of the nation and should be used to tackle the country's obesity crisis and other social problems.

The organisation is to conduct a study to produce evidence to show how people can improve their health and longevity by contact with nature. It is calling on the Government to enlist GPs to persuade their patients to take regular walks in the countryside or in local green spaces.

Natural England believes that as part of next year's review of GPs' pay, specific incentives should be included to ensure that doctors help to improve the nation's fitness. And it has advised ministers that natural green spaces should be included in all future designs for schools, hospitals, offices and housing developments. Targets for local authorities to improve rights of way and upgrade footpaths are also recommended.

The report says: “People's lives are often blighted by local crime and antisocial behaviour. Studies have shown that the presence of natural green space and vegetation is associated with a 50 per cent reduction in the incidents of violent crime and property damage.”

Natural England risks antagonising some rural campaigners with its commitment to on-shore wind farms but it is to press ahead and compile a map of the locations it considers most suitable for such projects. In its manifesto for change it says: “Space must be found for renewable energy, even if this means taking difficult decisions for long term gain.”

Similarly, it identifies that management of flood risk as a priority. It has already provoked opposition in the East of England after suggesting that the sea wall should be breached over parts of the Norfolk Broads to save the rest of the county.

A final report to ministers on this issue is due in September but the agency says: “Our national flood management strategy must work with nature, not against it. Using natural habitats on the coast instead of hard defences, restoring the uplands to reduce run-off, and re-creating wetlands in our river valleys to increase flood storage capacity will be important elements of our flood defences of the future.”

The Campaign to Protect Rural England is disappointed that the strategy fails to address concerns about the loss of landscape quality and tranquillity. It believes that Natural England is concerned more with protecting wildlife than human enjoyment.

The Country, Land and Business Association is dismayed that the report has failed to acknowledge the moves to greener farming after reform of the Common Agricultural Policy. It accused Natural England of ignoring the conservation contribution of many land managers.

The RSPB offered support to Natural England and called for extra government funding for environmental issues. Sue Armstrong-Brown, its head of countryside conservation, said: “There has never been a time when human action has put so much wildlife in peril.”

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