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 and biochemical analyses of soil under winter wheat in a field trial with various cultivation systems (organic, conventional and monoculture) were performed during 3 growing seasons: 2001, 2002 and 2003. The activities of the tested enzymes (dehydrogenase and phosphatases) and microbial biomass C and N contents in the monoculture soil were generally significantly lower than those in t...

Moisture may limit microbial activity in a wide range of environments including salt water, food, wood, biofilms, and soils. Low water availability can inhibit microbial activity by lowering intracellular water potential and thus reducing hydration and activity of enzymes. In solid matrices, low water content may also reduce microbial activity by restricting substrate supply. As pores within so...

Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial bioma...

Soil microbial communities play an important role in plant health and soil quality. Researchers have developed a wide range of methods for studying the structure, diversity, and activity of microbes to better understand soil biology and plant-microbe interactions. Functional microbiological analyses of the rhizosphere have given new insights into the role of microbial communities in plant nutri...

1 Plant and microbial nitrogen (N) dynamics were examined in soils of an Arctic salt marsh beneath goose-grazed swards and in degraded soils. The degraded soils are the outcome of intensive destructive foraging by geese, which results in vegetation loss and near-irreversible changes in soil properties. The objective of the study was to determine whether vegetation loss led to a decline in micro...

All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciation and availability. We studied the effects of heavy metal speciation and availability on soil microorganism activities along a Cu/Zn contamination gradient. Microbial biomass and ...

We analyzed the volatile organic compounds (VOCs) emitted from different soils by using the PTR-MS-TOF technique under laboratory conditions and compared them with soil chemical biochemical activities. The emitted VOCs were related to soil microbial biomass, soil respiration and some soil enzyme activities so as to evaluate if size and activity of soil microbial communities influenced the soil ...

In this study, total heavy metal content and its effects on soil microbiological characteristics were investigated in soil samples from an area with known long-term pollution problems. The total heavy metal concentrations of contaminated soil samples were 109 and 1,558 mg/kg for Hg and As, respectively. Key microbiological parameters measured included dehydrogenase activity, ATP content and num...

The knowledge about microorganisms-activity and diversity under hop production is still limited. We assumed that, different systems of hop production (within the same soil and climatic conditions) significantly influence on the composition of soil microbial populations and its functional activity (metabolic potential). Therefore, we compared a set of soil microbial properties in the field exper...