Extracellular enzymes degrade complex organic compounds and contribute to carbon turnover in soils. We used physical fractionation procedures to investigate whether soil carbon is spatially isolated from degradative enzymes across a prairie restoration chronosequence in Illinois, USA. We found that carbon-degrading enzymes were abundant in all soil fractions, including macroaggregates, microagg...

Quantitative knowledge of stabilizationand decomposition processes is necessary to understand, assess and predict effects of land use changes on storage and stability of soil organic carbon (soil C) in the tropics. Although it is well documented that different soil types have different soil C stocks, it is presently unknown how different soil types affect the stability of recently formed soil C...

Carbon dioxide efflux and soil microenvironmental factors were measured diurnally in Carex aquatilusand Eriophorum angustifolium-dominated riparian tundra communities to determine the relative importance of soil environmental factors controlling ecosystem carbon dioxide exchange with the atmosphere. Measurements were made weekly between 18 June and 24 July 1990. Diurnal patterns in carbon dioxi...

Global carbon budget studies are currently dominated by temperature analysis since the importance of this meteorological variable on photosynthesis processes and soil carbon dynamics. Yet, the strong coupling between the carbon and hydrological cycles is a longstanding acquisition of the biogeophysical sciences. To take the important aspect of water limitation in carbon studies into account, wa...

Carbon sequestration refers to the process of transferring carbon dioxide (CO2) from the atmosphere into the soil. A significant fraction of carbon stored in the soil is stable and, consequently, can remain in the soil for decades or longer. This process of transferring or “sequestering” carbon from the atmosphere helps off-set emissions from combustion of fossil fuel and other human-related ac...

Soil moisture is of primary importance for predicting the evolution of soil carbon stocks and fluxes, both because it strongly controls organic matter decomposition and because it is predicted to change at global scales in the following decades. However, the soil functions used to model the heterotrophic respiration response to moisture have limited empirical support and introduce an uncertaint...

Measuring changes in soil carbon levels is a difficult task. Uncertainty about soil carbon measurement, monitoring, and verification is affecting agriculture’s role as an offset provider under a cap-and-trade program. There is ample evidence that skepticism is warranted. Soil carbon varies significantly at short distances—the carbon difference between samples collected within a meter can easily...

Introduct ion .................................................................................................................................... 3 1 1 Carbon Cycling in Forested Wetland So i l s .................................................................................. .3 12 Carbon Fluxes Inputs .............................................................................................

evaluation of carbon input is one of the most important factors for estimating soil carbon changes and potential for carbon sequestration. to evaluate the net primary productivity (npp) and soil carbon input in agricultural eco-systems of iran, data for yield, cultivated area, harvest index (hi) and shoot /root ratio in different crops including: wheat, barley, maize, cotton, rice, alfalfa and ...