crops every 3 yr) and even continuous (annual) cropping in some instances. For example, annualized grain yields Water is the principle limiting factor in dryland cropping systems. for WCF are 75 to 100% greater than WF (Peterson et Surface soil physical properties influence infiltration and cropping al., 2000). Cropping intensification has been possible systems under no-till management may affe...

In arid and semi-arid regions, where precipitation is low or infrequent during the dry season, it is necessary to store the maximum amount of rainwater during the wet season for use in the agriculture sector. Rainfall in the Kingdom of Saudi Arabia takes place primarily during winter and spring seasons. The amount of rainfall ranges from 0.1 to 0.2 m in the area extending from north of Riyadh t...

As atmospheric emissions of S have declined in the Northern Hemisphere, there has been an expectation of increased pH and alkalinity in streams believed to have been acidified by excess S and N. Many streams and lakes have not recovered. Evidence from East Bear Brook in Maine, USA and modelling with the groundwater acid-base model MAGIC (Cosby et al. 1985a,b) indicate that seasonal and yearly v...

A disaggregation algorithm is applied to 40 km resolution SMOS (Soil Moisture and Ocean Salinity) surface soil moisture using 1 km resolution MODIS (MODerature resolution Imaging Spectroradiometer), 90 m resolution ASTER (Advanced Spaceborne Thermal Emission and Reflection radiometer), and 60 m resolution Landsat-7 data. DISPATCH (DISaggregation based on Physical And Theoretical scale CHange) d...

vegetation that is allowed to naturally decompose isn’t realized by many ranchers and some range mangers. Mulch plays a critical role in soil-water relationships that is often overlooked. This, coupled with current drought conditions in the southwestern United States justifies a consideration of the importance of mulch on rangelands. Several early classic studies (reviewed in this article) reve...

Abstract. Compaction and salinization of soils reduce croplands fertility, affect natural ecosystems, are major concerns worldwide. Soil compaction alters soil structure affects the soil's hydraulic properties, it therefore may have a significant impact on evaporation solute transport processes in soil. In this work, we investigated combined compaction, bare evaporation, salt precipitation. X-r...

Budyko (1974) postulated that long-term catchment water balance is controlled to first order by the available water and energy. This leads to the interesting question of how do landscape characteristics (soils, geology, vegetation) and climate properties (precipitation, potential evaporation, number of wet and dry days) interact at the catchment scale to produce such a simple and predictable ou...

The statistical-dynamical annual water balance model of Eagleson (1978) is a pioneering work in the analysis of climate, soil and vegetation interactions. This paper describes several enhancements and modifications to the model that improve its physical realism at the expense of its mathematical elegance and analytical tractability. In particular, the analytical solutions for the root zone flux...

The hydrology and geochemistry of groundwater in tropical island aquifers, such as Barbados, Guam and Puerto Rico, are significantly influenced by tropical climatic conditions. Recharge to these aquifers is the product of regional and local climate patterns that control rainfall. Oxygen isotopes can be used to estimate the amount and timing of recharge on these islands because seasonal fluctuat...