The authors reconstructed May–September precipitation over the Asian continent (58–558N, 608–1358E) back to AD 1470 on the basis of tree-ring data, historical documentary records, ice core records, and the few long-term instrumental data series available in the region. They employed the method of Regularized Expectation Maximization (RegEM) and applied it to 44 subregions within the continent. ...

[1] The complex interactions between plants, soils, and climates in semiarid ecosystems make it difficult to define specific ecohydrological optimization mechanisms that underlie observed spatiotemporal patterns of vegetation structure. There remains a clear need to develop conceptual models that are capable of interpreting and predicting spatial pattern formation in savannas (and similar dry w...

In spite of substantial introduction of new sorghum and millet cultivars in semiarid SubSaharan Africa, there has been minimum aggregate impact on yields (FAO and ICRISAT, 1996: The World Sorghum Economies: Facts, Trends and Outlook. FAO, Rome, Italy and ICRISAT, Andhra Pradesh, India) in contrast with other crops, such as cotton and maize. Only where inorganic fertilizers and improved water re...

Mountains provide as much as 90-100% of the freshwater to surrounding basins in arid and semiarid regions because of their distinctive and complex topography, and the consequent effects on precipitation (P) and evapotranspiration (ET). One of the primary objectives of this dissertation is to estimate mountain-block recharge (MBR), an important component of the mountain contribution to groundwat...

Our objective was to determine if long-term increases in precipitation can maintain grasslands susceptible to desertification, and initiate a reversal of historic regime shifts on desertified shrublands. Perennial grass production and species richness in a multi-year wet period were hypothesized to be greater than expected based on precipitation in a sequence of dry years. These responses were ...

The aim of this study was to assess the magnitude of evaporation loss from the Agricultural Water Reservoirs (AWRs) for Irrigation at a regional scale and to analyse its impact on water storage efficiency. To this end, we identified the extant AWRs for irrigation in the Segura River Basin (SRB) in southeastern Spain, and calculated the water loss from each AWR per month and year. In order to ac...

recently, the most important topic in water management was to determine the effects of urban forests and green space on partitioning gross rainfall (gr) into the rainfall interception (i), stemflow (sf), and throughfall (tf). the main aim of this research was to quantify the seasonal variations [growing season (gs), and non-growing season (ngs)]) in i by individual fraxinus rotundifolia trees i...

abstract alluvial fans are the most striking phenomena o fluvial geomorphology . these forms are found in frount of mountains and pediments of arid and semiarid zones . alluvial fans are affected by climate changes and tectonics . occurring of tectonic events lead to reaction of alluvial fans . some of these reactions appear on dissection of alluvial fans and displacement of depocenters on allu...

Quantifying the local crop response to irrigation is important for establishing adequate irrigation management strategies. This study evaluated the effect of irrigation applied with subsurface drip irrigation on field corn (Zea mays L.) evapotranspiration (ETc), yield, water use efficiencies (WUE = yield/ETc, and IWUE = yield/irrigation), and dry matter production in the semiarid climate of wes...

Climate change will result in increased precipitation variability with more extreme events reflected in more frequent droughts as well as more frequent extremely wet conditions. The increase in precipitation variability will occur at different temporal scales from intra to inter-annual and even longer scales. At the intra-annual scale, extreme precipitation events will be interspersed with prol...