Although there appears to be some evidence to suggest that the concentration of CO2 in the soil may have A model that couples the diffusion of O2 to plant roots at the an effect on plant growth, the major effect of poor microscale to diffusion of O2 through the soil at the macroscale is derived. The solution is complex, but if the length scales (Zr and Zm; aeration on plant growth is the lack o...

The state of compactness is an important soil structure and quality attribute, and there is a need to ®nd a parameter for its characterization that gives directly comparable values for all soils. The use of some relative bulk density value for this purpose, particularly the degree of compactness (HaÊkansson, 1990), is discussed in this review. The degree of compactness has been de®ned as the dr...

The effect of poultry waste application on physicochemical and biological properties of sandy clay loam soil was investigated on a 7m X 7m plot of land. Plot was divided into four portions and 7.5kg each of broiler, cockerel and layers waste was applied to plot A, B, and C in slurry form while plot D was used as control(no application) for eight weeks with two weeks interval. After the fourth a...

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...

The Wells G and H Superfund site, located in the Aberjona watershed in Woburn, Massachusetts, has been studied by a number of MIT research groups since 1987. Initial research conducted to characterize the hydraulic properties of the wetland deposits, did not indicate the classical trend linking changes in hydraulic conductivity to changes in total porosity. It was hypothesized, therefore, that ...

soil compaction has become a widespread problem in the world and it is considered as one of the main factors affecting land degradation in arid and semi-arid agricultural land. the aim of this study was to investigate the effects of soil compaction on soil carbon and nitrogen sequestration, physical (aggregate stability, saturated soil moisture content, bulk density, and porosity) and chemical ...

The proposed on-site zero-water discharge system was comprised of four main components: anaerobic tank, aerobic bioreactor, activated soil filter and water-collecting well. The results demonstrate that at 350 m(3) day(-1) of hydraulic load, the system can effectively remove pollutants from the wastewater, e.g., 86% removal of COD; 87% removal of SS; 80% removal of TP and 71% removal of TN. The ...

Physical, chemical and biological attributes of soil surface are significantly affected by tillage practices and crop rotation. The objective of this study was to determine the short-term (2006-2009) effects of conventional and conservational tillage practices on selected soil physical properties of a heavy clay soil under two wheat-corn and wheatlegume rotation in a semi-arid Mediterranean...