Invasions versus reserves
One of the aims of reserves is the conservation of the natural environment, which provides suitable conditions for the life of the original species and preserves the biodiversity. However, biodiversity is decreasing nowadays. A smaller area of suitable habitats, invasive species, and climate change are factors causing a decrease in biodiversity.
In addition, on the one hand, in Europe intensive human activities contribute to the decrease, on the other hand, Europe has a large network of protected areas, for example: national parks, smaller reserves, and the European NATURA 2000 network.
What is the role of reserves in processes leading to a lack of biodiversity? That was a key question of the article. The authors studied the distribution of protected and invasive species in protected areas and made the scenarios for developments under climate change.
Results show that a quarter of the continental reserves were affected by invasive species and in the case of marine reserves in 38%. In total, 85% of the colonized area is situated outside the nature reserves. Therefore, the occurrence of invasive species in the protected areas is lower. They colonize Central and north-eastern Europe at most. Moreover, study shows that older reservations better resist the effects of invasive species. These reserves are often situated in less accessible areas and thus it is hard for invasive species to invade those areas.
The probability of greater pressure by invasive species will be increasing with higher temperatures. They would spread from the core in north-western Europe to the northern and eastern parts of Europe. In marine ecosystems, the spreading would not be as great, also in terms of the point of view of the direction and speed of the invasion.
Hand in hand with warming, expansion from the south will be taking place as well. Repeatedly, the older reserves promise better protection. They are more remote, with natural habitats and a richer composition of species. On the other hand, the relatively recently established NATURA 2000 network is affected by invasions much more than state reserves, with management against the invasive species.
Therefore, reserves play an important role. They are strategic refugia with natural species and with protection from invasive species.