[1] We studied soil properties of frost boils at nine zonal-vegetation locations across the North American Arctic Transect (NAAT) in order to better understand arctic soils and their interaction with other biogeophysical components of frost boil ecosystems. Soil genetic horizons were analyzed for particle size, pH, electrical conductivity, total organic carbon (OC) and nitrogen (N), bulk densit...

Soil sickness is a critical problem for eggplant (Solanum melongena L.) under continuous cropping that affects sustainable eggplant production. Relay intercropping is a significant technique on promoting soil quality, improving eco-environment, and raising output. Field experiments were conducted from September 2010 to November 2012 in northwest China to determine the effects of relay intercrop...

Rice grown on a flooded Sumatra Oxisol soils frequently exhibits poor growth and low yield. A study has been made of the effects of pH and redox conditions on growth and nutrient uptake by rice, and the relationship between nutrient release in the flooded soil and nutrient uptake by the rice plant. At pH 4.5 rice plants produced low plant height, low root dry weight, low shoot dry weight, slow ...

November or before April because soils either are frozen or too wet. Soil temperature at the time of application has been the primary It has been recommended that fall applications of N factor used to predict rates of nitrification and assess the risks associbe delayed until soil temperature has decreased to 10 C ated with losses of N applied in the fall as anhydrous ammonia in the at a depth o...

Short-chain fatty acids can be produced under anaerobic conditions by fermentative soil microbes and have nematicidal properties. We evaluated the effects of butyric and propionic acids on death and recovery of stunt nematodes (Tylenchorhynchus spp.), a common parasite of turfgrass. Nematodes in a sand-soil mix (80:20) were treated with butyric or propionic acid and incubated under air or N for...

Effects of heavy metal pollution on the enzymatic activities of soils were investigated in the Ishiagu mining area of Ebonyi State, Nigeria. Soil dehydrogenase, polyphenol oxidase, hydrogen peroxidase, alkaline and acid phosphatases and urease were measured to evaluate the effects of heavy metals mining operations on soil biochemical characteristics. Results showed that the soil pH ranged from ...

Experiments with potted plants and removed understories have indicated that understory vegetation often affects the chemical and microbial properties of soil. In this study, we examined the mechanism and extent of the influence of understory vegetation on the chemical and microbial properties of soil in plantation forests. The relationships between the vegetational structure (diversity for diff...

Fungi (Rhizopus stolonifer, Trichoderma viride, Fusarium oxysporum f. sp. conglutinans, Cunninghamella echinulata, and several species of Aspergillus and Penicillium) tolerated higher concentrations of cadmium (Cd) when grown in soil than when grown on laboratory media, indicating that soil mitigated the toxic effects of Cd. In soil amended with clay minerals, montmorillonite provided partial o...

The microbial ecology of the nitrogen cycle in agricultural soils is an issue of major interest. We hypothesized a major effect by farm management systems (mineral versus organic fertilizers) and a minor influence of soil texture and plant variety on the composition and abundance of microbial nitrifiers. We explored changes in composition (16S rRNA gene) of ammonia-oxidizing archaea (AOA), bact...

We studied microbial communities in two paddy soils, which did not receive nitrogen fertilization and were distinguished by the soil properties. The two microbial communities differed in the relative abundance of gram-negative bacteria and total microbial biomass. Variability in microbial communities between the two fields was related to the levels of phosphorus and soil moisture. Redundancy an...