Enhanced soil respiration in response to global warming may substantially increase atmospheric CO2 concentrations above the anthropogenic contribution, depending on the mechanisms underlying the temperature sensitivity of soil respiration. Here, we compared short-term and seasonal responses of soil respiration to a shifting thermal environment and variable substrate availability via laboratory ...

wind is an important erosive force in deserts, where limited cover of vascular plant material offers little soil-surface protection. erosion and sediment from soil surfaces occurs when wind forces exceed soil threshold friction velocities. soils with physical or biological crusts usually resist wind erosion. this study was conducted by the aim of investigation the effect of trichoderma harzianu...

Terrestrial ecosystems are intimately connected to atmospheric CO2 levels through photosynthetic fixation of CO2, sequestration of C into biomass and soils, and the subsequent release of CO2 through respiration and decomposition of organic matter. Considering all the pools and fluxes of C within ecosystems, C-cycling belowground is increasingly being recognized as one of the most significant co...

soil salinity induces a stressful environment for soil micro-organisms and reduces their number and activity. the objective of this research is investigating the effect of different levels of salinity on some of soil biological indicators and also assessing the effect of two types of halotolerant rhizospheric bacteria on the value of these indexes in soil. 35 strains were isolated from saline r...

An assessment of roles of rhizospheric microbial diversity in plant growth is helpful in understanding plant-microbe interactions. Using random combinations of rhizospheric bacterial species at different richness levels, we analysed the contribution of species richness, compositions, interactions and identity on soil microbial respiration and plant biomass. We showed that bacterial inoculation ...

This lecture reviews the past (since 1964 when the International Biological Program began) and the future of our understanding of terrestrial carbon fluxes with focus on pho-tosynthesis, respiration, primary-, ecosystem-, and biome-productivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rat...

We examined the effect of decomposing leaf litter and dissolved inorganic nutrients on the heterotrophic biofilm of submerged wood in streams with and without leaves. Leaf litter was excluded from one headwater stream in August 1993 at Coweeta Hydrologic Laboratory in the southern Appalachian Mountains. We compared microbial processes on wood in the litter-excluded stream to a reference stream ...

The non-target effects of Amistar (azoxystrobin) and Score (difenoconazole) were studied in terms of changes in the soil microbial populations, soil respiration and activity of soil enzymes. Both the fungicides significantly reduced the fungal population in the soils even at the lowest concentration used (0.44 g. (a.i.) g soil) and totally eliminated it at the recommended dose for field applica...

Microbial activity measurements (oxygen transfer rate, OTR, carbon dioxide transfer rate CTR and respiratory quotient, RQ) are used to monitor and control biological processes. In this study, the digestion of activated sludge in microaerobic conditions was evaluated. The changes of biological activity during digestion were monitored by respiration activity. The sludge mixtures used were primary...