Understanding the variation in the hydrological response of a basin associated with land use changes is essential for developing management strategies for water resources. The impact of hydrological changes caused by expected land use changes may be severe for the Wami river system, given its role as a crucial area for water, providing food and livelihoods. The objective of this study is to examine the influence of land use changes on various elements of the hydrological processes of the basin. Hybrid classification, which includes unsupervised and supervised classification techniques, is used to process the images (2000 and 2016), while CA-Markov chain analysis is used to forecast and simulate the 2032 land use state. In the current study, a combined approach-including a Soil and Water Assessment Tool (SWAT) model and Partial Least Squares Regression (PLSR)-is used to explore the influences of individual land use classes on fluctuations in the hydrological components. From the study, it is evident that land use has changed across the basin since 2000 (which is expected to continue in 2032), as well as that the hydrological effects caused by land use changes were observed. It has been found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period. These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources' use.

Scarcity of fresh high-quality water has heightened the importance of wastewater reuse primarily in dry regions together with improving its efficient use by implementing the Subsurface Drip Irrigation (SDI) method. Sustainable effluent reuse combines soil and plant aspects, along with the maintainability of the application system. In this study, field experiments were conducted for two years on the commercial farm of Revivim and Mashabay-Sade farm (RMF) southeast of the City of Beer-Sheva, Israel. The purpose was to examine the response of alfalfa (Medicago sativa) as a perennial model crop to secondary domestic effluent application by means of a SDI system as compared with conventional overhead sprinkler irrigation. Emitters were installed at different depths and spacing. Similar amounts of effluent were applied to all plots during the experimental period. The results indicated that in all SDI treatments, the alfalfa yields were 11% to 25% higher than the ones obtained under sprinkler irrigated plots, besides the one in which the drip laterals were 200 cm apart. The average Water Use Efficiency (WUE) was better in all SDI treatments in comparison with the sprinkler irrigated plots. An economic assessment reveals the dependence of the net profit on the emitters' installation geometry, combined with the return for alfalfa in the market.

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Knowledge of regional groundwater flow behavior is important in water management. However, modeling and estimation of aquifer parameters for very complex aquifer system, like the one considered here for Osaka area, by mathematical models is notoriously difficult. This paper concerns with such complex aquifer system by relatively simple model that is the tank model, so as to understand the major mechanism of such aquifer system. The major difficulty in developing such model is the trade-off between the fit of the observed data to the model response and reliability of the parameter estimation. Random start optimization procedure together with Akaike's Information Criterion, AIC, has been employed to overcome this problem. A stable model is established which is believed to be reliable to simulate the groundwater flow pattern of the Osaka plain aquifer. The results also suggest disconnection of some regional aquifers as well as inflow of seawater to the deeper layers in the studied period. A tank model associated with the optimization technique and statistical procedure proposed in the study offers a promising approach in reliably understanding the mechanism of a complex regional groundwater flow system such as studied in this paper, Osaka plain aquifer system.