Nature protection and biodiversity - Outlook 2020 (France)

The national sustainable development strategy has taken on the challenge of ensuring the conservation and sustainable management of biodiversity and natural resources by combating the artificialisation of the environment and the homogenisation of landscapes. The artificialisation of the countryside is a threat not only to potential agri-food production but also to ecosystems and the natural environment.

Development policies must manage conflicts over land usage. In order to do that, they must ensure that equilibrium is respected, the continuity of ecosystems is guaranteed, in particular by the formation of a network of ‘green and blue threads’, and harmonious interpenetration is encouraged between urban, rural, agricultural and natural landscapes. Development policies must also help to preserve the ‘character’ of the environment and landscape as an additional cultural, aesthetic and tourism asset of human activity.

Climate change and biodiversity

The effects of climate change on biodiversity have been mentioned for ten years or so in the context of international conventions, and scientists have been talking about them for even longer. These effects are as yet not all detectable, and uncertainties still exist, above all concerning the severity of disturbances and the capacity of species to adapt to them. Other factors are also involved, such as developments in human activities.

Although there are models which enable us to estimate the effects of climate change on species or habitats, certain phenomena are already starting to be observed. For example, there are reports of changes in the physiology of individuals and their behaviour. Changes are occurring, for example, in  the flowering and fructification dates of plants, and in the dates, routes and altitudes of migration, breeding and resting sites of birds or butterflies. Amphibians and Lepidoptera seem to be the most vulnerable groups. In the marine environment, overseas there are reports of the bleaching of corals, a reduction in their rate of recovery and progressive changes in their reefs. There is a risk that they will disappear in a few decades owing to rising temperatures, aggravated by tourism and sporting activities.

In addition, the geographical distribution of species is changing. Movements have been observed in altitude and towards the north. Generalised species tend to expand at the expense of more specialised species, leading to the homogenisation of communities. Native species are becoming more vulnerable and this, plus the effects of globalisation, facilitates the arrival and expansion of invasive or proliferating species, such as the water primrose (Ludwigia grandiflora), the Japanese knotweed (Fallopia japonica) and the red swamp crayfish (Procambarus clarkii). It also encourages the extension of the ranges of various pests, such as the urticating caterpillars of the pine processionary moth (Thaumetopoea pityocampa) which has been extending its range in metropolitan France for thirty years, also giving rise to health problems and economic problems.