Traditionally, soil-testing laboratories have used a variety of methods to determine soil organic matter, yet they lack a practical method to predict potential N mineralization/immobilization from soil organic matter. Soils with high microbial activity may experience N immobilization (or reduced net N mineralization), and this issue remains unresolved in how to predict these conditions of net m...

Many aspects of plant water use -- particularly in response to soil drought -- may have as their basis the alteration of hydraulic conductance from soil to canopy. The regulation of plant water potential (Psi) by stomatal control and leaf area adjustment may be necessary to maximize water uptake on the one hand, while avoiding loss of hydraulic contact with the soil water on the other. Modellin...

The effect of water availability on water relations of 11-year-old loblolly pine stands was studied over two growing seasons in material from two contrasting seed sources. Increasing soil water availability via irrigation increased transpiration rate, and maximum daily transpiration rate on irrigated plots was similar for both seasons, reaching values of 4.3 mm day(-)(1). Irrigation also change...

The potential sensitivity of ecological models to differences in soil temperature and soil water from land-surface models was evaluated by using model output from the PILPS land-surface model comparison. Simulated soil water and temperatures from the land-surface models were used to calculate the abiotic decomposition factor (ADF). ADF is used by ecosystem models to directly control microbial a...

Soil erosion implications on future food security are gaining global attention because in many areas worldwide there is an imbalance between soil loss and its subsequent deposition. Soil erosion is a complex phenomenon affected by many factors such as climate, topography and land cover (in particular forest resources, natural vegetation and agriculture) while directly influencing water sediment...

*T. C. Caesar-TonThat and V.L. Cochran, USDA-ARS Northern Plains Agricultural Research Laboratory, 1500 North Central, Sidney, MT 59270 *Corresponding author: [email protected]. ABSTRACT Loss of water stable aggregates due to excessive tillage has increased the potential for soil erosion in semiarid farming-systems. Fungi can be responsible for the resistance of soil aggregates to brea...

Although tree- and stand-level estimates of forest water use are increasingly common, relatively little is known about partitioning of soil water resources among co-occurring tree species. We studied seasonal courses of soil water utilization in a 450-year-old Pseudotsuga menziesii (Mirb.) Franco-Tsuga heterophylla (Raf.) Sarg. forest in southwestern Washington State. Soil volumetric water cont...

Drinking water treatment facilities remove impurities from raw water sources using various chemicals. The by-product produced from the purification process is called water treatment residuals (WTR). If WTR contain residual chemicals from the purification process, soluble elements may be released potentially causing chemical imbalances in soil and groundwater systems. The study objectives were t...

Stomatal characteristics affecting gas exchange were compared in two sweet corn hybrids (var. Bonanza and Monarch Advance) which differ in foliar ozone sensitivity. No significant differences were observed in stomatal frequencies, guard cell lengths, or conductances to water vapor diffusion.When plant water status was compared, leaf-water potentials for the ozone-resistant cultivar, Bonanza, we...