  Climate changes may affect ecosystems destabilising relationships among
species. We investigate the spatial rock-paper-scissors models with a regional
unevenness that reduces the selection capacity of organisms of one species. Our
results show that the regionally weak species predominates in the local
ecosystem, while spiral patterns appear far from the region, where individuals
of every species play the rock-paper-scissors game with the same strength.
Because the weak species controls all local territory, it is attractive for the
other species to enter the local ecosystem to conquer the territory. However,
our stochastic simulations show that the transitory waves formed when organisms
of the strong species reach the region are quickly destroyed because of local
strength unbalance in the selection game rules. Computing the effect of the
topology on population dynamics, we find that the prevalence of the weak
species becomes more significant if the transition of the selection capacity to
the area of uneven rock-paper-scissors rules is smooth. Finally, our findings
show that the biodiversity loss due to the arising of regional unevenness is
minimised if the transition to the region where the cyclic game is unbalanced
is abrupt. Our results may be helpful to biologists in comprehending the
consequences of changes in the environmental conditions on species coexistence
and spatial patterns in complex systems.
