Volatilization of pesticides from soils under dry conditions (water content below the permanent wilting point) can be significantly influenced by sorption to hydrated mineral surfaces. This sorption process strongly depends on the water activity, expressed as equilibrium relative humidity in the pore space of the soil, and on the available surface area of the hydrated minerals. In this study, t...

Despite the dominance of microorganisms in arid soils, the structures and functional dynamics of microbial communities in hot deserts remain largely unresolved. The effects of wetting event frequency and intensity on Namib Desert microbial communities from two soils with different water-regime histories were tested over 36 days. A total of 168 soil microcosms received wetting events mimicking f...

With little precipitation (<10 cm water equivalent annually as snow), soils of the McMurdo Dry Valleys (MDV) have limited water available to support hydrological or biogeochemical processes. Active layer depths across most of this landscape are <1 m. Saturated sediments are obvious in wetted margins on the shorelines of lakes, extending for up to ~10 m into a zone where typically arid MDV soils...

Hydrocarbon contamination of unsaturated soils has been a serious environmental problem for decades. Two of the most common methods of remediating these sites are soil vapour extraction (SVE) and bioventing. Predictive models have been developed for the SVE and bioventing processes in order to estimate mass transfer coefficients for experimental systems and clean up times for field sites. These...

In tropical regions, soil acidity and low soil fertility are the most important yield-limiting factors for sustainable crop production. Using legume cover crops as mulch is an important strategy not only to protect the soil loss from erosion but also to ameliorate soil fertility. Information is limited regarding tolerances of tropical legume cover crops to acid soils. A greenhouse experiment wa...

Climate change is occurring globally, with wide ranging impacts on organisms and ecosystems alike. While most studies focus on increases in mean temperatures and changes in precipitation, there is growing evidence that an increase in extreme events may be particularly important to altering ecosystem structure and function. During extreme events organisms encounter environmental conditions well ...

Seed priming is a physiological seed enhancement method. Hydroor osmotic priming can advance germination under adequate moisture conditions. During direct seeding on well-drained paddy and upland fields, rice seeds occasionally encounter low soil moisture conditions. Under these conditions, rice seeds need to undergo rapid germination and secure emergence through improved water absorption capac...

Seventy years of different management treatments have produced significant differences in runoff, erosion, and ponded infiltration rate in a winter wheat (Triticum aestivum L.)–summer fallow experiment in OR, USA. We tested the hypothesis that differences in infiltration are due to changes in soil structure related to treatment-induced biological changes. All plots received the same tillage (pl...

This study examined the effect of tree species identity and diversity on soil respiration in a 3-year-old tropical tree biodiversity plantation in Central Panamá. We hypothesized that tree pairs in mixed-species plots would have higher soil respiration rates than those in monoculture plots as a result of increased primary productivity and complementarity leading to greater root and microbial bi...

This study aimed to investigate and discuss the occurrence and accumulation of mercury in the fruiting bodies of wild-growing fungi (Macromycetes) collected from montane forests in two regions of southwestern China with differences in soil geochemistry, climate and geographical conditions. Fungal mycelia in soils of the subalpine region of the Minya Konka (Gongga Mountain) in Sichuan and in the...