We examined fine-root (< 2.0 mm diameter) respiration throughout one growing season in four northern hardwood stands dominated by sugar maple (Acer saccharum Marsh.), located along soil temperature and nitrogen (N) availability gradients. In each stand, we fertilized three 50 x 50 m plots with 30 kg NO(3) (-)-N ha(-1) year(-1) and an additional three plots received no N and served as controls. ...

The role of grass tussocks in supporting soil microbial biomass (SMB) in grazed ecosystems is not fully understood, nor is the spatial distribution of SMB in response to different grass species. We undertook a study in 1997 that examined ®ne-scale distributions of SMB in grazed experimental paddocks located in the eucalypt woodlands of northern Queensland, Australia. Levels of SMB were determin...

The major portion of the global nitrogen cycle occurs between vegetation and soil, only minor exchanges generally taking place with the atmosphere and the hydrosphere. Nitrogen conversions in soil are briefly reviewed and a global flow chart for soil nitrogen is presented. The turnover times of nitrogen in various components of this global system are compared with its turnover times in some sel...

Improving water use efficiency and soil properties are two major factors for sustainable development in desert areas. Therefore, this research aims to study the effectiveness of a biological hydrogel, plant vegetation layer, sand and barley straw with rain harvesting techniques through micro-catchment operation on some soil properties including pH, Nitrogen, Electrical conductivity, Sodium Abso...

As potent allelochemicals, phenolic acids are believed to be associated with replanting disease and cause microflora shift and structural disorder in the rhizosphere soil of continuously monocultured Radix pseudostellariae. The transcriptome sequencing was used to reveal the mechanisms underlying the differential response of pathogenic bacterium Kosakonia sacchari and beneficial bacterium Bacil...

Surface soil and groundwater in Australia have been found to contain high concentrations of arsenic. The relative importance of long-term human exposure to these sources has not been established. Several studies have investigated long-term exposure to environmental arsenic concentrations using hair and toenails as the measure of exposure. Few have compared the difference in these measures of en...