After Brexit the UK would no longer be covered by EU directives designed to protect wildlife habitats and wild birds.
A new report by environmental law academics from five universities warns that the loss of European Union (EU) law on nature and pollution is likely to create major problems.
And, they say, it could lead to standards being relaxed by the UK Government.
The report,by the Scottish Universities Legal Network on Europe, points out that the UK and Scottish authorities have failed to comply with air pollution standards.
The report said: “Losing the EU law’s enforcement edge and the EU Commission’s oversight of the most important conservation sites may be especially problematic.
“In the absence of EU law obligations, both Scottish and UK authorities may relax their standards on air quality,”
“Brexit will entail the loss of a powerful means of scrutiny over how the UK manages its environment, with no obvious replacement for it.
“Instead, UK citizens will only be able to access national courts to complain about breaches of domestic environmental law.”
One of the report’s authors, Dr Annalisa Savaresi from the University of Stirling, argued that Brexit meant the loss of the stable regulatory framework provided by EU law.
She said: “Following withdrawal from the EU, existing regulatory and policy differences between Scotland and the rest of the UK may sharpen.
“Whether EU powers will, by default, go to the Scottish Parliament and other devolved administrations, or will be re-reserved to Westminster is yet to be seen.
“The latter question is likely to require discussion between central and devolved governments across the UK.”
Environment Secretary Roseanna Cunningham thought the report was a reminder of the “deeply worrying” implications of the Brexit vote.
“But no-one should doubt our determination to protect and enhance Scotland’s natural environment,” she said.
“Our membership of the European Union has driven up environmental standards and we have all benefited as a result. I am not prepared to see those benefits lost.”
The Scottish Wildlife Trust argued that it was vital for the Scottish Government to retain EU environmental standards.
The trust’s chief executive Jonny Hughes said: “If these laws cease to apply or are watered down the health of our natural environment could be severely compromised.
“There have been a number of welcome assurances from the Environment Secretary that the Scottish Government will continue to adhere to the standards of protection currently in place.
“However, we believe it will be important to identify how any new legislation can be enforced in the long term.”