Issue 1

The developing nations are worst affected as they are largely dependent on the local precipitation and soil moisture for their livelihood generations. The changing climate with extended summer, change in the rainfall pattern (intensity and duration) and variations of onset and departure of seasons are directly impacting the cultivation, status of natural vegetation, surface and sub-surface water, and other natural resources in a watershed area. Among the various efforts, watershed development approach, in which intervention is more site-specific in nature and can address the local requirements, is found to be more effective at micro levels. The vulnerability of climatic changes is mainly due to water stress, degradation of natural vegetations, degradation in the health and hygiene conditions, and poor information communication technology. The present article highlights these issues, impact of watershed development project in the Himalayan region and identifying the adaptation mechanism through watershed programs. A site specific action, research methods including primary and secondary data collections, GIS, remote sensing and statistical techniques were used. The study on the Jusho Bakro micro-watershed treated by TERI under the program DROP has been found to be effective in drawing possible adapting mechanism to withstand the changing climate and its severity on the natural resources and the livelihood of the community.

This study was conducted to investigate the effect of praestol, as a coagulant-aid, to improve coagulation-flocculation process in the removal of disperse red 60 from aqueous solutions. The effect of various parameters including coagulants dose (10-1000 mg l^-1), praestol dose (0-1000 mg l^-1), solution pH (3-11), initial dye concentration (100-500 mg l^-1), flocculation speed (30-60 rpm), flocculation time (15-30 min), settling time (5-60 min) and ionic strength (0-6 mg l^-1) was evaluated on the dye removal. The dye removal efficiency was substantially increased by using praestol in the concentration of 80 mg l^-1 and 400 mg l^-1 for coagulation with alum and polyaluminum chloride (PACl), respectively. The maximum dye removal by alum coupled with praestol (Al-P) and PACl coupled with praestol (PA-P) was found to be 97.8% and 98.7%, respectively that were occurred at pH 7. The results showed that the application of PA-P or Al-P can be effectively used to remove disperse red 60 (DR 60) in aqueous solutions.

The need for efficient and economical use of the world’s water requires the implimentation of modern methods to make decisions about water management. This inspired the principal philosophy of the management study of the Hellenic part of the Strymonas River catchment (6400 km²). An important issue in such studies is to simulate the hydrology of the river catchment. The state-of-the-art couple model MIKE SHE/MIKE 11 is a powerful, physically-based distributed hydrological and hydraulic simulation tool. To determine water balance, hydrology and hydraulic functions in the river catchment a water level monitoring network was established. Data collection was performed during 2004 and 2006. The philosophy and main assumptions that underlie the current work are described. Furthermore, the effectiveness of the irrigation networks in the Strymonas River basin is checked. Finally, the negative effect of the current irrigation network on the lake’s water level fluctuation is pointed out and simple but effective solutions are proposed.

In this work, the effectiveness of electro-Fenton process degradation of sodium dodecylbenzene sulfonate (SDBS) anionic surfactant in acidic wastewater was investigated. Taguchi method was applied to study the effect of process parameters on oxidation of SDBS pollutant. An orthogonal array L₉ experimental design that allows investigating the simultaneous variation of current density, initial acidity of wastewater, and the initial SDBS concentration was employed to evaluate the effect of these parameters as control factors. Taguchi experimental design in dynamic sense was carried out with electrolysis time chosen as signal factor. Each experiment comprises the addition of peroxide (170 mg l^-1; 0.005M) as a fixed component of Fenton's reagent and NaCl (1.5 mg l^-1) as supportive electrolyte. The results revealed that SDBS degradation in acidic aqueous phase, can reached high values by the electro-Fenton process. The estimation of linear model coefficients for S/N (signal to noise) ratios expression has acceptable fitness of 93.5% with the selected control and signal factors. Main effects and analysis of variance (ANOVA) indicates that the current density and the acidity have high impact on electro-Fenton degradation of SDBS process with high sum of squares and low p-values that signifies the 0.05 α-level. Moreover, Taguchi optimal analysis indicates that high S/N ratio of response can be obtained with 0.3 mA cm^-2 current density,
pH=2 initial acidity of wastewater, and 10 mg l^-1 initial SDBS surfactant concentration.