Spatial variability is a major source of uncertainty in estimating the fluxes of greenhouse gases between steppe and atmosphere. The fluxes of CO2, CH4, and N2O were carried out between 08:00 and 10:00 h. of the following day during the midsummer period from a transect (area: 5.25×10 ha) in the semiarid steppe of northern China, using the dark static chamber technique and gas chromatography. Tw...

A common feature of microbial colonization in deserts is biological soil crusts (BSCs), and these comprise a complex community dominated by Cyanobacteria. Rock substrates, particularly sandstone, are also colonized by microbial communities. These are separated by bare sandy soil that also supports microbial colonization. Here we report a high-throughput sequencing study of BSC and cryptoendolit...

Gravely calcareous soils cover approximately most of arid lands (in percent); however, the solute transport behavior in these soils remains a current issue. This research aimed at estimating and correlating the solute transport parameters in gravely calcareous soils as being affected by different land uses through the knowledge of the soil morphological, physical, and chemical properties. Four ...

We conducted a 3-year study designed to examine the relationship between disturbance from military land use and stream physical and organic matter variables within 12 small (<5.5 km2) Southeastern Plains catchments at the Fort Benning Military Installation, Georgia, USA. Primary land-use categories were based on percentages of bare ground and road cover and nonforested land (grasslands, sparse ...

A mixture of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) (Telone C35) is an increasingly used fumigant product for pre-plant soil fumigation in California, USA. Atmospheric emissions of volatile organic compounds, including these important pesticides, is more heavily regulated in an effort to improve air-quality. Research has identified various methods of reducing fumigant emissions but e...

Carbonyl sulfide (COS) and dimethyl sulfide (DMS) fluxes from an urban Cynodon dactylon lawn and adjacent bare soil were measured during April-July 2005 in Guangzhou, China. Both the lawn and bare soil acted as sinks for COS and sources for DMS. The mean fluxes of COS and DMS in the lawn (-19.27 and 18.16 pmol/(m2 sec), respectively) were significantly higher than those in the bare soil (-9.89 ...

Methanogens typically occur in reduced anoxic environments. However, in recent studies it has been shown that many aerated upland soils, including desert soils also host active methanogens. Here we show that soil samples from high-altitude cold deserts in the western Himalayas (Ladakh, India) produce CH4 after incubation as slurry under anoxic conditions at rates comparable to those of hot dese...

plant litter is an important factor for soil conservation and sustainability that could modify soil chemical properties and increase the plant biomass production. the aim of this research was to compare plant litter chemical composition and its effects on soil properties in three species including hordeum bulbosum, poa bulbosa, bromus tectorum. first, soil samples were taken in the depth of 0-3...

Soil respiration (Rs) is a major pathway for carbon cycling and is a complex process involving abiotic and biotic factors. Biological soil crusts (BSCs) are a key biotic component of desert ecosystems worldwide. In desert ecosystems, soils are protected from surface disturbance by BSCs, but it is unknown whether Rs is affected by disturbance of this crust layer. We measured Rs in three types of...

Plant litter is an important factor for soil conservation and sustainability that could modify soil chemical properties and increase the plant biomass production. The aim of this research was to compare plant litter chemical composition and its effects on soil properties in three species including Hordeum bulbosum, Poa bulbosa, Bromus tectorum. First, soil samples were taken in the depth of 0-3...