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We analyzed the changes of potential evapotranspiration during the past 50 years, measured as the pan evaporation in the hyperarid region. We quantified the influence of water, radiation and aerodynamic attributions of the overall trend of potential evapotranspiration in this study region and analyzed the implications to hydroclimate and water balance in this region. This phenomenon implies that the region would face to more severe water scarcity in future. We also try to demonstrate the changes in water balance in this region will be facing an accelerated or enhanced cycle which implies that the increased river discharge and evapotranspiration will cause large challenge in water resources management. Both the ecosystems and social systems will be expected to facing with severe water problems under the climate warming scenarios. [ABSTRACT FROM AUTHOR]

This chapter contains sections titled: Introduction, Water Content of the Body, Water as a Nutrient, Water Balance, Water Requirement, Water Delivery to the Pig, Water Management, Water Quality, Water Treatment, Water Quality Effects on Performance, References [ABSTRACT FROM AUTHOR]

A decrease in total area of tropical forests is considered as a significant factor that influences landscape functioning, including the hydrological cycle; it contributes to climate change, and has many other consequences. This paper presents the extent of deforestation in Nakuru and Naivasha region (Rift Valley, Central Kenya) between the years 1986 and 2005 and its effects upon thermal characteristics of the landscape. Such changes have immense impact on hydrological regimes of the Rift Valley lakes in central Kenya. Multispectral data from Landsat TM, ETM+ and Terra Aster were used to determinate dense and humid forests as well as their changes over time. A field observation, realized during the ˵dry″ rainy season in October 2008, confirmed evident decline of precipitation and consequent low water discharge from the deforested catchment in the rivers and water level in lakes. [ABSTRACT FROM AUTHOR]

The Aral Sea has drastically shrunk over the past 50 years, largely due to water withdrawal from the Amudarya and Syrdarya rivers for land irrigation. If one were to look back over the Holocene,1 the paleolimnology of the Aral Sea is however already marked by the occurrence of several phases of regression and transgression. They resulted partly from climate change, for tectonic reasons, and over the last 2,000 years anthropogenic actions also played a role. After a short review of the paleohistory of the Aral Sea, we will focus on a description of the causes and magnitude of episodes of historical (last 100 years) Aral Sea level variability. The Aral Sea has been marked since the middle of the last century by a process of desiccation due to increase of water intake from the Amudarya and Syrdarya rivers for agricultural purposes. This led to the separation of the Aral Sea into two (in 1986–1987) and then four (in 2009) water bodies. Measurements of Aral Sea water level and surface and water balance were carried out by both in situ gauges and remote-sensing satellite data. This allows for a better understanding of the seasonal, interannual, and decadal trend in Aral Sea water storage variations. [ABSTRACT FROM AUTHOR]

The elements of the water balance, namely precipitation, runoff, evapotranspiration, and storage change, their interaction and special attributes in the mountains are presented using the example of the European Alps, with particular reference to Switzerland. Strong differentiation in the alpine climate over time and space exerts a significant influence on the water cycle. This chapter therefore discusses each of the elements of the water balance with particular reference to the influence of mountains and their measurement, as well as the spatial differentiation characteristics. The analysis of the water balance is accompanied by a discussion on the attributes and differences at different altitudes and in different climatic regions. Finally, the importance of alpine water resources for water supplies in the adjacent lowlands is examined. [ABSTRACT FROM AUTHOR]

A 7-year research project into the long-term performance of reclaimed landscapes on saline-sodic overburden from oil sands mining in north-central Canada has demonstrated the importance of a multi-disciplinary approach. The land capability assessment tool used by the industry evaluates three key areas: available soil moisture, salt impact, and biological response (including nutrients). Detailed field monitoring and sampling demonstrated the relative performance of three different layered covers (35, 50 and 100 cm) and one monolayer cover (100 cm) through the tracking of water content, suction, stored water volumes, interflow/runoff and water availability for plant growth. Salt ingress into the cover from the underlying waste and salt release through interflow flushing has also been monitored. This long-term monitoring has provided physically based measurements of cover performance that clearly highlight the inability of thin (35 cm) or monolayer covers for providing sufficient moisture to meet all demands throughout a growing season. Interpretation of this data has also provided key insights into the mechanisms governing cover performance. This physically based evaluation was supported by direct measurements of tree development and tree ecophysiology. Vegetation indicators included plant species composition and abundance, tree growth rates, foliar nutrient contents, and plant ecophysiology. [ABSTRACT FROM AUTHOR]