This work deals with the implementation of a soil organic matter model in an individual-based modelling framework. The simulator INDISIM-SOM models the dynamics of carbon and nitrogen related to soil organic matter and the soil microbial activity by using a discrete simulation. This simulation model controls the activity of group of microbial cells in a space divided into square cells where amo...

of plant residue C and N. Application of 15N-labeled fertilizer or maize residue together resulted in more than The role of mineral fertilizer-N inputs and N deposition to agricultwice as much 15N recovered from fertilizer than from tural and natural ecosystems can affect plant residue decomposition and soil C processes. Yet it is still unclear whether residue-N or residue in the SOM (Dourado-N...

Soil quality indicators and nematode abundance were characterized in a loessial soil under long-term conservation tillage to evaluate the effects of no-till, double-disk, chisel, and moldboard plow treatments. Indicators included soil electrical conductivity (EC), soil texture, soil organic matter (SOM), and total particulate organic matter (tPOM). Nematode abundance was positively correlated w...

We analyzed relations between the content of total organic carbon (TOC) and the content of soil organic matter (SOM) in 47 soil profiles dug out in dry coniferous forests, fresh coniferous forests, and mixed deciduous-coniferous forests. Soils in the analyzed sites are derived from sands. In each soil horizon, bulk density (BD), pH, soil texture, and TOC and SOM were determined. Correlation bet...

In situ chemical oxidation is a commonly applied soil and groundwater remediation technology, but can have significant effects on soil properties, which in turn might affect fate and transport of organic contaminants. In this study, it was found that oxidation treatment resulted mainly in breakdown of soil organic matter (SOM) components. Sorption of naphthalene and phenanthrene to the original...

Isotope pool dilution studies are increasingly reported in the soils and ecology literature as a means of measuring gross rates of nitrogen (N) mineralization, nitrification, and inorganic N assimilation in soils. We assembled data on soil characteristics and gross rates from 100 studies conducted in forest, shrubland, grassland, and agricultural systems to answer the following questions: What ...

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...

This paper reviews the current knowledge of microbial processes affecting C sequestration in agroecosystems. The microbial contribution to soil C storage is directly related to microbial community dynamics and the balance between formation and degradation of microbial byproducts. Soil microbes also indirectly influence C cycling by improving soil aggregation, which physically protects soil orga...

Interest in soil organic matter (SOM) is ramping up as concern mounts about steadily increasing levels of atmospheric CO2. There are two reasons for this. First, there is hope that improvements in crop, forest, and soil management may allow significant amounts of CO2 to be removed from the atmosphere and sequestered in soil. Second is the possibility that increased soil respiration rates, assoc...

Soil organic matter contains fractions that range from very active to passive, relative to microbiological activity Soil organic matter (SOM) contains fractions that range from very (Schimel et al., 1985), suggesting that classification of active to passive, relative to microbial-driven ecosystem processes and functions. A classification system is needed that can test the hypothesis SOM forms m...