Sombra

Pesquisa



Impacts of human disturbance on plant diversity in the cork oak woods of Chréa in northern Algeria

The cork oak woods of the Chréa Biosphere Reserve in northern Algeria are showing the effects of human activities that have profoundly modified the plant landscape. Recurrent wildfires and overgrazing are the main causes of disruption to the existing woodland formations, causing losses of both wooded areas and plant biodiversity. Our aim was to identify how the vegetation in the Quercus suber L. ecosystem in this reserve is reacting to the environmental conditions and disruption arising from human activity. To do so, we used a synchronous approach involving 124 phytoecological surveys conducted at different dynamic stages and taking into account the presence or absence of disturbance due to grazing. An initial canonical correlation analysis of the floristic data was performed, followed by a second on the vital attributes of each species, using easily measurable variables (biological type, Grime's adaptive strategy, mode of dissemination). Our results show that plant life in these cork oak woods is organised along a gradient of degradation associated with human action (wildfires and grazing), which masks the effects of the dominant mesological factors (altitude and exposure). The functional approach confirms these regressive dynamics by individualising two functional groups: the first covers the "phanerophyte, competi-tion-stress, zoochory" characteristics of the most mature plant formations, while the second encompasses the "therophyte, stress-ruderal, anemochory" characteristics associated with the open formations of overgrazed grasslands. This study, conducted via a functional approach to biodiversity, provides an initial assessment of the responses of Algeria's cork oak woods to disturbances of human origin, in this case wildfires and overgrazing.

Ver mais

footer logos