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A conceptual model for water-limited evapotranspiration taking into account root depth, root density, and vulnerability to xylem cavitation
Published in N. Khalili, A.R. Russell, A. Khoshghalb, Unsaturated Soils: Research & Applications, 2020
Alessia Amabile, Brunella Balzano, Marco Caruso, Alessandro Tarantino
Evapotranspiration can occur under two different regimes, ‘energy limited’ and ‘water limited’ evapotranspiration. Energy limited evapotranspiration, also referred to as potential evapotranspiration, occurs when water can be made available by the soil-plant system. Under these circumstances, evapotranspiration is controlled by the energy supplied by solar radiation, required to convert liquid water into vapour water (latent heat of evaporation). Evapotranspiration is driven by the evaporative demand of the atmosphere, i.e. relative humidity differential and wind speed.
Solar energy and evapotranspiration: A control of the unsaturation state in soils
Published in H. Rahardjo, D.G. Toll, E.C. Leong, Unsaturated Soils for Asia, 2020
Evapotranspiration is a major term in the soil water balance and results from the conversion of solar energy reaching the soil surface. In arid and semi-arid regions of the earth, solar energy has a considerable capacity to evaporate water from the earth’s surface, whether from free water surfaces, vegetated or bare soil or the surfaces of soil-like waste deposits. The evaporative capacity in humid regions is also not inconsiderable, but may be more than balanced by precipitation. Solar radiation nevertheless operates effectively in all climates and its contribution to overall water losses can be predicted and exploited with benefit.
Climate Change Impacts on Groundwater
Published in Mohammad Karamouz, Azadeh Ahmadi, Masih Akhbari, Groundwater Hydrology, 2020
Mohammad Karamouz, Azadeh Ahmadi, Masih Akhbari
The recharge quantification and its controls are important for the water-resources evaluation and for analyzing the groundwater sensitivity to contamination. Areas with high recharge rates are particularly most prone to pollution. In arid areas, the combination of the climatic impacts and the land-use changes leads to the increased groundwater recharge due to the deforestation, which reduces the evapotranspiration despite the fact that it favors runoff.
Impacts of combined and separate land cover and climate changes on hydrologic responses of Dhidhessa River basin, Ethiopia
Published in International Journal of River Basin Management, 2022
Gizachew Kabite Wedajo, Misgana Kebede Muleta, Berhan Gessesse Awoke
The land cover change affects hydrological processes by altering evapotranspiration (ET), soil water holding capacity of a soil, infiltration, precipitation interception capacity (Chen & Li, 2004; Feddema et al., 2005; Zhang et al., 2014), and runoff travel times (Zhang et al., 2014). Consequently, land cover change modifies the quantity and quality of both subsurface and surface waters (Niraula et al., 2015; Wang et al., 2014), the frequency and magnitude of drought and floods (Brath et al., 2006) and regional and global climate systems. At the basin scale, the effects of changes in land cover on hydrologic responses are reflected in the supply-and-demand balance of water resources, which, in turn, affect ecosystems, environment, and economy (Shi et al., 2013). Generally, the combined and separate effects of changes in climate and land cover influence the environment particularly the hydrological processes of a basin (Chen et al., 2019; Dwarakish & Ganasri, 2015; Hailu et al., 2021; Megersa et al., 2021).
Hydrological impacts of urban expansion in a Brazilian metropolis – Case study of the Vargem das Flores reservoir catchment
Published in Urban Water Journal, 2022
Deyvid Wavel Barreto Rosa, Talita Fernanda Das Graças Silva, Rogério Palhares Zschaber de Araújo, Nilo de Oliveira Nascimento
Urbanization profoundly changes the land cover, with vegetation removal and the increase of impervious surfaces, altering inputs to the hydrological cycle. Infiltration decreases, lowering the natural groundwater recharge, the water table level and consequently the groundwater flow (Bhaskar et al. 2016; Wakode et al. 2018). Urbanization can decrease the baseflow in streams and increase surface runoff, flow velocity and pollutant build-up and washoff, leading to greater variations in flow throughout the year, rising frequency and intensity of floods and pollutant load into water bodies (Silva et al. 2022; Mohamed, Gitau, and Engel 2020; He, Minxue, and Hogue 2012; Elizabeth, Schulte, and Richards 2002). Deforestation associated with urban expansion also decreases evapotranspiration and rainfall interception by the vegetation cover (Zheng et al. 2020).
Evapotranspiration estimation using SEBAL algorithm integrated with remote sensing and experimental methods
Published in International Journal of Digital Earth, 2021
Nazila Shamloo, Mohammad Taghi Sattari, Halit Apaydin, Khalil Valizadeh Kamran, Ramendra Prasad
Evapotranspiration is one of the most important factors in the hydrological cycle and is a key determinant of energy equations on the earth's surface. Evapotranspiration is a combination of two processes responsible for water losses that include evaporation (directly from the soil) and transpiration (from the plants). It is difficult to consider these two processes separately since they occur almost simultaneously at varied rates with high spatial variability (Allen et al. 1998b). As a result, evapotranspiration estimates are important for hydrology, irrigation, forest and rangeland, and water resources management. The evapotranspiration drives the soil water-energy balance which is largely used in general circulation models and climate modelling. Consequently, river water flow forecasting, crop yield forecasting, irrigation management systems, river/ lake water quality are all dependent on evapotranspiration levels (Ozturk and Apaydin 1998; Bastiaanssen et al. 2005; Razaji et al. 2020; Yamaç 2021). For this reason, it is essential to accurately estimate the water budget (Goyal and Harmsen 2013; Shabani et al. 2020). Better and accurate evapotranspiration estimates would allow for effective irrigation planning and optimal water usage for other agricultural purposes (Sattari et al. 2020a).