Understanding karst landscape evolution through ecosystems: cave connectivity and isolation

Abstract

Variability in landscapes drives patterns in biological communities and is often used to understand biological systems. Rarely, however, have biological systems been used to understand landscape evolution. Here, we review the geomorphic history of cave development in the southern Sierra Nevada Mountains and look at the detail that modern biological systems can add to our understanding of this region's geomorphic history. Cave development has occurred in isolated bands of marble. As water has dissolved rock and downcut through the mountain range, macro-invertebrate communities have colonized these new habitats. Over time, as connectivity patterns have changed between caves, these communities have been isolated from each other. Through looking at similarities and differences between communities, we can delve further into how cave features are connected or have been connected in the past. We calculated Jaccard distance to assess community similarity between caves in the Kaweah River Basin, California. Caves in the same marble band had similar biota, and caves with distinct geomorphic histories had divergent biological communities. This suggests that ecosystems can inform us about the evolution of these landscapes and that this approach may be used to answer other landscape evolution questions.