An important component in calculating budgets of terrestrial soil carbon is an estimate of total soil organic carbon. The CENTURY model simulates organic C in the top 20 cm of soil only, so a method for projecting the depth distribution of organic C is necessary for estimates of the profile total. This document describes the implementation of the exponential depth distribution of organic C in C...

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

Soil organic C content, a major source of system stability in agroecosystems, is controlled by many factors that have complex interactions. The purpose of this study was to evaluate the major controls over soil organic carbon content, and to predict regional patterns of carbon in range and cultivated soils. We obtained pedon and climate data for 500 rangeland and 300 cultivated soils in the U.S...

On a sequence of soils developed under similar vegetation, temperature and precipitation conditions, but with variations in mineralogical properties, we use organic carbon and C inventories to examine mineral protection of soil organic carbon. In these soils, C data indicates that the creation of slow-cycling carbon can be modeled as occurring through reaction of organic ligands with Al and Fe ...

abstract soil drying and rewetting (drw) cycles are considered as environmental stress that would affect the physical, chemical and biological properties of soil and nutrient cycles. the study of soil drying and rewetting effects on plant nutrition and soil fertility is very important and crucial specially their environmental effects. in this study, the effects of 1, 2, 3, 4 and 5 drying and re...

[1] Post-fire storage of carbon (C) in organic-soil horizons was measured in one Canadian and three Alaskan chronosequences in black spruce forests, together spanning stand ages of nearly 200 yrs. We used a simple mass balance model to derive estimates of inputs, losses, and accumulation rates of C on timescales of years to centuries. The model performed well for the surface and total organic s...

Plant-derived carbon compounds enter soils in a number of forms; two of the most abundant being leaf litter and rhizodeposition. Our knowledge concerning the predominant controls on the cycling of leaf litter far outweighs that for rhizodeposition even though the constituents of rhizodeposits includes a cocktail of low molecular weight organic compounds which represent a rapidly cycling source ...

Soil carbon accumulation is largely dependent on net primary productivity. To our knowledge, there have been no studies investigating the dynamics of carbon accumulation in weathered subtropical soils, especially in managed eucalyptus plantations. We quantified the seasonal input of leaf litter, the leaf decomposition rate and soil carbon stocks in an commercial plantation of Eucalyptus saligna...