.soil microorganisms are important agents in nutrient cycling and energy flow. they are extremely sensitive to environmental changes. soil microbial biomass has been proposed as an index of soil stress and disturbance. the objective of this study was to determine the effects of barley (hordeum vulgare l.) residue amounts, burning, nitrogen fertilizer levels and tillage management on organic car...

dissolved organic nitrogen (don) can react with disinfectants to produce numerous disinfectionbyproducts (dbps), particularly nitrogen-containing dbps (n-dbps), and produce serious adverse effectson public health. widely used biological processes in drinking water treatment can increase don in effluents,and enhance these ill effects. this study investigated don in a full-scale two-stage ozonati...

dissolved organic nitrogen (don) can react with disinfectants to produce numerous disinfectionbyproducts (dbps), particularly nitrogen-containing dbps (n-dbps), and produce serious adverse effectson public health. widely used biological processes in drinking water treatment can increase don in effluents,and enhance these ill effects. this study investigated don in a full-scale two-stage ozonati...

This study was conducted to investigate the effect of dairy cow diets containing different protein sources [soybean meal, xylose protected soybean meal (Yasminomax®), and steam-flaked whole soybean] and various partially processed grain on in vitro gas production kinetics and the microbial nitrogen yield. Soybean meal (S) and xylose protected of soybean meal (XS) were provided as 0.56:...

land use change of forest ecosystems in northern iran changes the soil quality of paresar (gilan province) and gorgan (gorgan province) regions. in order to study changes in some biological soil quality indices due to land use change from forest to cultivated lands, composite soil samples from two depths (0-20 and 20-40 cm) were taken from paresar and gorgan regions and urease, alkaline and aci...

Microbial biomass nitrogen and carbon were studied in long-term field experiments with continuous cultivation of silage maize and with crop rotation. a positive effect of organic fertilizers on the microbial biomass nitrogen and the carbon content in soil was observed. Statistically significant effect of organic fertilizers on the higher content of microbial biomass C and n was established in t...

Levels of nitrogen in coastal areas have been rapidly increasing due to accumulative inputs of sewage and terrigenous sediments carrying fertilizers. Sponges have an immense filtering capacity and may be directly impacted (positively or negatively) by elevated concentrations of nitrogen. Sponges also host a wide diversity of microbes involved in nitrogen metabolism, yet little is known about th...

toxicity and damages caused by soil pollution with crude oil and its microbial responses may depend on nitrogen bioavailability and its form. so, the main objective of this study is to investigate the effects of crude oil and various forms of n consumption on c mineralization and microbial biomass. the experiment was done in the form of factorial (3×4) design using crd (completely randomized de...

Nitrogen (N) is an essential element in biological systems and one that often limits production in both aquatic and terrestrial systems. Due to its requirement in biological macromolecules, its acquisition and cycling have the potential to structure microbial communities, as well as to control productivity on the ecosystem scale. In addition, its versatile redox chemistry is the basis of comple...

Historically, terrestrial food web theory has been compartmentalized into interactions among aboveground or belowground communities. In this study we took a more synthetic approach to understanding food web interactions by simultaneously examining four trophic levels and investigating how nutrient (nitrogen and carbon) and detrital subsidies impact the ability of the belowground microbial commu...