Soil organic matter dynamics: a cross-ecosystem approach
Soil C accumulation and turnover are important processes globally: soils contain about 1.5 x 1018 g C, which is 2 3 times that in vegetation. The C flux between soils and the atmosphere is large, with soil respiration representing about 10 times the C flux due to fossil fuel combustion. Thus, any temperature or land-use-induced change in rates of soil C turnover will markedly affect the global C cycle.
Many LTER sites have active experiments that might alter soil C dynamics, including the DIRT network, soil warming, chronic N fertilization, management/species diversity experiments, etc. However, the degree of soil organic matter dynamics analysis varies greatly among these experiments, ranging from simple bulk C and N analysis, to complex density and size physical fractionation procedures followed by pyrolysis-GC/MS, AMS dating, CuO oxidation, and many other analytical procedures. The purpose of this workshop is to bring together researchers interested in soil C dynamics to discuss research questions as well as site inter-comparisons and standardization of techniques. We will discuss not only analytical methods, but also potential cross-site analyses that could use the power of the LTER network – a series of ecosystems that span broad gradients of soil textures and mineralogies vegetation, and climate – to elucidate generalizations about soil organic matter dynamics.