Acacia, climate, and geochemistry in Australia

摘要: In anticipation of global climate change, the question whether shifts in plant community composition (beta-diversity) are predictable from environmental variation is receiving considerable interest. Species strongly associated with local soil environments may be more vulnerable to change than species a broad tolerance conditions. Here we investigate relationships between climate, geochemistry and distribution Acacia over Australia. We use geostatistics estimate total Ca, Mg, Na, Al, P, pH, electrical conductivity at sites where have been recorded Australian Virtual Herbarium database. compare median predicted reported substrate for individual that appear extreme conditions; this provides partial evaluation predictions. generate site-by-species matrix by aggregating observations centroids grid cells 100 km on edge, calculate diversity indices, numerical ecology methods (ordination, partitioning) its response climatic geochemical gradients. Many tolerate conditions range restricted. genus widely distributed across Australia but strong associations exist turnover geochemistry. Climate, EC account much continent, especially southern Climate together half about 60–80 % areas high richness. The unique contribution smaller except most rich areas. important explaining northern Geochemical variables occurrence richness Australia—it further other genera. Aridification, which has driven some observed extremes concentrations, key process landscape evolution as well biogeography. This study underscores Australia’s place natural laboratory evolutionary