A recent paper by Knorr et al. (2005a) suggested that the decomposition of resistant soil organic matter is more temperature sensitive than labile organic matter. In Knorr et al.’s (2005a) model, the reference decay rate was presumed to be same for all pools of soil carbon. We refit Knorr et al.’s (2005a) model but allow both the activation energy and the reference decay rate to vary among soil...

ElevatedCO2may increasenutrient availability in the rhizospherebystimulatingNrelease fromrecalcitrant soil organic matter (SOM) pools through enhanced rhizodeposition. We aimed to elucidate how CO2induced increases in rhizodeposition affect N release from recalcitrant SOM, and howwild versus cultivated genotypes of wheat mediated differential responses in soil N cycling under elevated CO2. To q...

We quantified and compared carbon (C) pools at a Missouri Ozark experimental forest 8 years after different harvest treatments. Total C pools were 182, 170, and 130 Mg C ha–1 for the control (no-harvest management; NHM), singletree, uneven-age management (UAM), and clearcut even-age management (EAM) stands, respectively. Harvesting reduced the live tree C pool by 31% in the UAM, 93% in EAM stan...

Vegetative growth serves as an important means to capture and store atmospheric carbon dioxide in biomass and soil. Grassland soils are high in soil organic carbon and contain an extensive fibrous root system that creates an environment ideal for soil microbial activity. Accurate quantification of SOC pool is needed to generate benchmark information for the present and to determine the changes ...

Previous analyses of soil water beneath mounds resulting from scarification have implied that this forestry measure increases leaching of inorganic N. However, more recent soil-water studies have not confirmed this assumption. The soil study presented here examined the pools of inorganic N in different microsites emanating from a simulated disc trenching, i. e. the mound with underlying soil, t...

more, different ecosystems are limited or controlled by a variety of factors, so that understanding why certain Soil is a potential C sink and could offset rising atmospheric CO2. ecosystems respond and others do not will become imThe capacity of soils to store and sequester C will depend on the rate of C inputs from plant productivity relative to C exports controlled portant for understanding ...

Changes in soil organic carbon (SOC) stability may alter carbon release from the soil and, consequently, atmospheric CO2 concentration. The mean annual temperature (MAT) can change the soil physico-chemical characteristics and alter the quality and quantity of litter input into the soil that regulate SOC stability. However, the relationship between climate and SOC stability remains unclear. A 5...

Global climate change may impact the cycling of C, N, and S in forest ecosystems because increased soil temperatures could alter rates of microbially mediated processes. We studied the effects of temperature on microbial respiration and net N and S mineralization in surface soils from four northern hardwood forests in the Great Lakes region. Soil samples were incubated in the laboratory at five...

this study was conducted to investigate the impact of land use change on some of carbon components in safashahr area, fars province. four land uses (destroyed rangeland, agricultural land, new and old apple orchard) were selected. sampling was done randomly from two depths (0-20 and 20-50 cm) of each land use. particulate organic matter (pom) and extractable carbohydrate by hot water were measu...

A quantitative laboratory assessment of the different C and N forms in soil humus fractions was carried out by incubation of a mineral substrate after the addition of (15)N-labeled compost. The experimental design included (i) preparation of the (15)N-labeled organic matter (city refuse compost, 640 g kg(-1) wheat straw and K(15)NO(3) composted for 80 days), (ii) a further 80 day incubation of ...