introduction:changes caused by grazing on range ecosystem are generally assessed based on the soil conditions and vegetation. livestock as one of the major elements in range land ecosystems has different effects on different parts of this ecosystem. one of these impacts is excessive livestock grazing capacity which can have different effects on soils and plants in various intensities. materials...

In soils under wheat cultivation, soil aggregates stability is increased and destructive effects of erosion decreased, due to organic matters (OM) application. This trail was conducted in Shavoor agriculture research station to determine of mean weight diameter (MWD) under different organic matter sources and amounts in Khuzestan province (at south west of Iran) via a split plot experiment base...

Microbial Carbon Sources on the Shelf and Slope of the Northwestern Gulf of Mexico. (August 2005) Carlton David Rauschenberg, B.S., DePaul University Chair of Advisory Committee: Dr. Luis A. Cifuentes Over the past five years, gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analyses of phospholipid fatty acids (PLFAs) has been increasingly used to link organic matter (...

Contents of total Hg and Hg fraction, organic matter, pH, grain size and chemical composition were measured to investigate the pollution characteristics and binding behavior of Hg in soils collected from the Chatian Hg mining deposit (CMD), southwestern China. The average concentration of Hg concentration in the CMD soils was 155 and 1,315 times higher than that in control soils and Chinese soi...

this study was conducted to investigate the type and origin of clay minerals via several profiles in lordegan hilly lands. the profiles were located in two kinds of land uses including forest and dry farm at different slope positions as sampling sites. the soil saples were collected from two depths of soil horizons to indicate cec, soil texture, oc%, calcium carbonate equivalent, x-ray diffract...

current ruminant feeding systems depend on knowledge of the composition of feeds and the rate and extent of degradation of feed organic matter (om) and crude protein (cp) in the rumen. the effect of storage and preparation of samples on in vitro gas production and fermentation characteristics of two common forage species, namely alfalfa and ryegrass werestudied. samples were prepared as fresh (...

Sludge applications have been used to maintain fertility of agricultural soils without damaging the natural ecosystem. The aim of this study was evaluating the influence of sewage-sludge addition on the quality of organic matter (OM) of a Brazilian Oxisol by Laser Induced Fluorescence (LIF). LIF was used to analyze OM of whole soil and different soil fractions separated by chemical and physical...