Effect of dynamic fragmentation on biodiversity in a heterogeneous environment

We study how the mode of dynamic habitat loss and fragmentation can impact the levels of biodiversity in an ecosystem. The problem is formulated into the framework of resource-based modelling and, opposed to previous studies relying on neutral models, here elements of niche theory are incorporated into the modeling by considering that the species are not ecologically equivalent. In our model the habitat loss is carried out by using a fractal landscape that is constructed through the use of fractional Brownian motion. Thus we can tune the roughness of the landscape by changing the Hurst exponent. We show that both the mode of habitat loss and the level of environmental heterogeneity influence the patterns of species distribution. We notice a larger impact of fragmentation on the number of species when the fragments are more compact. We observe that the relationship between biodiversity and heterogeneity is described by a one-humped function.