rise of groundwater levels in unconfined aquifers can cause dryland salinity to increase by several processes including; dissolution of windblown halite, and incorporation of saline clay pore water. The primary process of increased groundwater salinity is evaporation of shallow groundwater as it rises to within a few meters of the ground surface. in murray Basin, australia, the effect of drylan...

This paper presents a method for predicting areas at risk from dryland salinity using information derived from multi-temporal Landsat TM satellite images combined with landform data derived from high-quality digital elevation models. The method is applied in the south west agricultural region of Western Australia to predict areas at risk from dryland salinity. This paper presents modifications ...

Research on ecosystem and societal response to global environmental change typically considers the effects of shifts in mean climate conditions. There is, however, some evidence of ongoing changes also in the variance of hydrologic and climate fluctuations. A relatively high interannual variability is a distinctive feature of the hydrologic regime of dryland regions, particularly at the desert ...

Drylands occupy 6.15 billion hectares (Bha) or 47.2% of the world's land area. Of this, 3.5 to 4.0 Bha (57%-65%) are either desertified or prone to desertification. Despite the low soil organic carbon (SOC) concentration, total SOC pool of soils of the drylands is 241 Pg (1 Pg = petagram = 10(15)g = 1 billion metric ton) or 15.5% of the world's total of 1550 Pg to 1-meter depth. Desertification...

We present evidence to show that DAYCENT can reliably simulate soil C levels, crop yields, and annual trace gas fluxes for various soils. DAYCENT was applied to compare the net greenhouse gas fluxes for soils under different land uses. To calculate net greenhouse gas flux we accounted for changes in soil organic C, the C equivalents of N2O emissions and CH4 uptake, and the CO2 costs of N fertil...

For evaluating climate change impacts on biodiversity, extensive experiments are urgently needed to complement popular non-mechanistic models which map future ecosystem properties onto their current climatic niche. Here, we experimentally test the main prediction of these models by means of a novel multi-site approach. We implement rainfall manipulations--irrigation and drought--to dryland plan...

this experiment contained four vetch lines (vicia panonica ) that conducted in two locations (faruj and bojnourd) in 2005-2006 in rcbd design with four replications under dryland conditions. analysis of variance indicated that there were significant differences among lines in different locations about all traits, except 100-seed weight. the interaction of genotype×location was significant on al...