We hypothesized that soil carbon isotopic composition would be closely coupled to the signature of detrital inputs (the average δ13C of forest floor and fine-root biomass) and that the increase in δ13C with depth would be related to abiotic variables that influence soil carbon turnover rates.
"In other words, the soil's molecular carbon composition is shifting [toward] a form that is not usable to microbes or plants, and more of the remaining carbon is being derived from leaf cuticles that persist in the soil," she says.
SR is primarily influenced by microbial activity, the amount and composition of soil carbon, and regulating factors, such as climate (air temperature and precipitation) and soil variables (soil temperature, moisture, and texture).
However, soil layer, forest region and CAZy content consistently ranked highly followed by taxonomic composition and total soil carbon content.
Geochemist Carey Gazis, an assistant professor at Central Washington University in Ellensburg, received a $75,000 POWRE grant in September 1998 to study the oxygen isotope composition of soil water, soil carbon dioxide, and rain--key to understanding global atmospheric CO2.
Physical soil properties, such as soil structure, particle size, and composition, have profound impact on soil carbon (C).
Previously, we had reported for this area total carbon stocks for primary and secondary forests [52], rates of carbon uptake and release in primary forests [53], rates of above- and below-ground carbon accumulation in secondary forests [51], soil carbon balance [44], and changes in forest structure and composition along the successional sequence [54].
Previously, we had reported for this area total carbon stocks for primary and secondary forests [ 52], rates of carbon uptake and release in primary forests [ 53], rates of above- and below-ground carbon accumulation in secondary forests [ 51], soil carbon balance [ 44], and changes in forest structure and composition along the successional sequence [ 54].
These large regional differences in the isotopic composition of soil C at depth are attributed to variation in soil carbon turnover rates across the landscape.
Few studies have explored the successive impacts of plant litter composition on soil microbial structure and function, litter decomposition patterns and final soil carbon sequestration.
