elevated atmospheric carbon dioxide and other green house gases have increased the earth temperature in recent century, which it affects all biochemistry cycles in soils. to examine the effect of atmospheric co2 concentration and temperature on n forms in soil solution in a calcareous soil, an experiment was conducted in a completely randomized design with factorial arrangement in the laborator...

Soil particle density (rs) is not routinely measured and is assumed to range between 2.60 and 2.70Mgm or to be a constant (2.65Mgm) when estimating essential properties such as porosity, and volumetric water and air relations. Values of rs for the same soil may, however, differ significantly from the standard range due to managementinduced changes in soil organic carbon (SOC) concentrations.Weq...

Organic matter is mainly present in the top 20–30 cm of most soil profiles and is essentially an array of organic macromolecules consisting principally of combinations of carbon, oxygen, hydrogen, nitrogen, phosphorus and sulphur. Soil organic matter is commonly measured as the quantity of organic carbon. The global pool of organic carbon in soil to a depth of 1 m has been estimated at 1,200–1,...

BACKGROUND: Application of plant mulches plays a significant role in development and expansion of sustainable farming systems. OBJECTIVES: Assessment effect of chemical and non-chemical weeds management methods on weeds density and biomass and the properties of soil, including microbial biomass carbon (MBC) and soil organic carbon (SOC) in potato cultivation. ...

Playa wetlands are important areas of soil organic carbon and nutrient storage in drylands. We conducted this study to assess how catchment biophysical variables control soil organic carbon and nitrogen in playas and how playas function differently than upland ecosystems. We found that playa organic carbon and nitrogen corresponded primarily with catchment vegetation cover and secondarily with ...

The Tibetan Plateau reacts particularly sensitively to possible effects of climate change. Approximately two thirds of the total area is affected by permafrost. To get a better understanding of the role of permafrost on soil organic carbon pools and stocks, investigations were carried out including both discontinuous (site Huashixia, HUA) and continuous permafrost (site Wudaoliang, WUD). Three ...

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 .............................................................................................

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 ...