A transient one-dimensional model of the vertical movement of water and salt in the mangrove root zone is investigated. This is an extension of a previous steady state model which assumed that the ability of the mangrove roots to take up water is uniformly distributed throughout the soil and that the root water uptake is reduced if there is nonzero salt concentration around the roots. We show h...

Agricultural systems often require added phosphorus to achieve optimum crop and livestock production. The application of soil amendments, such as inorganic fertilizers, manure, biosolids, and waste water, can improve soil fertility and help produce optimum crop yields. However, many of these amendments, particularly organic materials such as animal manure, are often applied in excess of crop nu...

Soil bulk density is a physical property of soils that affects water storage, water and nutrient movement, and plant root activity in the soil profile. The ability to quantify soil bulk density using vibration-induced conductivity fluctuation was investigated with possible field applications in the future. The AC electrical conductance of soil was measured using a pair of blade-like electrodes ...

In clayey, swelling and more or less sodic soils, cultivation and seasonal climatic cycles induce variations in soil moisture which in turn cause variations in the soil structure. In particular, when the soil profile is saturated, some soils become impermeable because the soil porosity value does not remain sufficiently high throughout the drainage period to be effective for water movement. In ...

*Correspondence: Wei Shan, Institute of Cold Regions Science and Engineering, Northeast Forestry University, Harbin 150040, China e-mail: [email protected] Climate warming leads to permafrost degradation and permafrost melting phase transition, resulting in an increasing number of landslides. This study uses the road segments and road area at the intersection between Bei’an-Heihe Highway and t...

Four experimental plots located in Granada (Spain) were used to investigate the potential movement of the insecticide methidathion during three treatments in a period of three years. To increase pesticide soil retention a municipal biosolid and the cationic surfactant, tetradecyl trimethyl ammonium bromide (TDTMA), were used as soil amendments. The presence of the insecticide was monitored in s...

The magnitude of hydraulic redistribution of soil water by roots and its impact on soil water balance were estimated by monitoring time courses of soil water status at multiple depths and root sap flow under drought conditions in a dry ponderosa pine (Pinus ponderosa Dougl. ex Laws) ecosystem and in a moist Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) ecosystem. The fate of deuterated wat...

Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitratenitrogen (NO3-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO3-N concentrations in soil water at a 76 cm depth under ir...

[1] Nitrate (NO3 ) movement was studied using a combination of isotopic, chemical, and hydrometric data within the 135 ha Archer Creek watershed in the Adirondack Mountains of New York from January 1995 to December 1996. This research was conducted to identify sources of stream water NO3 and the mechanisms that deliver NO3 to the stream to test two hypotheses: (1) Soil water NO3 concentrations ...

MAMMALS and birds sometimes seek shelter or nesting sites in the ground. Many of them scarcely affect the soil as a medium for plant growth. A notable exception is the soil-dwelling rodents. Although their acreweight is usually only about a few pounds even in the uncultivated land, their soil transporting activities sometimes are considerable. In building their tunnels and nests, they transport...