Search

In India, the per capita availability of water is projected to be 1465 m3 and 1235 m3 by the years 2025 and 2050, respectively, and hence, India would be a water-stressed country as per the United Nations’ standard of less than 1700 m3 per capita water availability. India is predominantly an agricultural-dominant country. Rainfed agriculture in the country contributes 40% of food grain production and supports half of the human population and two-thirds of the livestock population. The country has 15 different agro-climatic zones, and each agro-climatic region has its own constraints of water availability and management along with the potential for their optimum utilization. Such situations warrant the formulation of regional-level strategies. Efforts were made to integrate and evaluate the feasibility of water harvesting and its utilization at twelve different sites representing six different agro-climatic conditions spanning pan India. It was found that water harvesting through tanks/ponds is a feasible approach and can increase the crop production as well as diversification. The results reveal that the range of crop diversification index increased from 0.49–0.85 to 0.65–0.98; the crop productivity index increased from 0.28–0.66 to 0.66–0.90; the cultivated land utilization index increased from 0.05–0.69 to 0.34–0.84; and the crop water productivity index increased from 0.20–0.51 to 0.56–0.96, among other production and diversification indices, due to additional water availability through rainwater harvesting intervention. Moreover, the gross return increased from INR 43,768–704,356 to INR 220,840–1,469,108 ha−1, representing a 108 to 400% increase in the returns due to the availability of water. The findings of this study suggest that the water harvesting in small ponds/tanks is economical and feasible, requires less technological intervention, and increases crop diversification in all the studied agro-climatic conditions, and hence, the same needs to be encouraged in the rainfed areas of the country.

Aims: Recent climate change impacts rainfall patterns, increasing wildlife and livestock populations in higher densities, which are likely to aggravate water scarcity in forest areas. A sustainable water management strategy and action plan based on scientific inputs are crucial and need of the hour to resolve the water scarcity problem. Hence, the study aims to prepare an action plan and water management strategy for rangelands of Nilgiris using geospatial tools. Study Design: Field survey was conducted to identify the existing water storage structures and water requirement and ASTER GDEM and GIS were used to prepare the water management strategies for Nilgiris south forest division. Place and Duration of the Study: The study was carried out in Nilgiris south division located in between 760 28' 08’’and 760 44' 08" East longitude and 110 10' 81’’and 110 31' 80" North latitude during 2014-2016. Methodology: The study area has been delineated as macro watersheds, and the altitude, slope, forest cover and drainage lines were extracted from ASTER GDEM for generation thematic maps. Rainfall data for twenty years (1995-2014) was collected and runoff was worked out using runoff coefficient of a different land. A field survey was conducted for identifying the existing water storage structures, spatial occupancy of herbivores, spread and water requirement of invasive species in the Nilgiris south forest division. Results: GIS based thematic maps for slope, contour, area coverage under forest range and macro watershed have been prepared, and water availability and water balance components like runoff and evapotranspiration have been determined. After identifying water availability and water balance according to the site conditions and strategies one Earthen cum masonry embankment, 2 Earthen pond with Major check dam, 2 Masonry embankments, 2 Major check dam 7 Medium check dam 100 Minor check dam, 1 RCC Embankment and 99 gabion check dams in South forest division of Nilgiris. Conclusion: Suitable locations were identified and location specific water harvesting structures have been suggested to store 68844 cum of water.

Aims: The impact of comprehensive interventions in erosion control, improving water availability, development of agro-forestry, sustainable management of natural resources, enhancement of agricultural productivity and socio-economic aspects of the farmers was studied. Assessment of effectiveness of watershed development programme, identification of major issues and lacunae in project implementation across the watersheds also has been studied. Study Design: Multistage stratified sampling technique was adopted in selection of study watersheds (secondary sampling unit-SSU), farmers (primary sampling units-PSU) and structures for detailed surveys. Place and Duration of the Study: The study was conducted in South Pennaiyar catchement in Dharmapuri, Salem, Villupuram, Vellore, Thiruvannamalai districts of Tamil Nadu. The study was conducted for three years period during 2012-14. Methodology: Sample based before and after project evaluation approach, employing budgeting techniques. By employing stratified random sampling method 15 study watersheds (SWS) were selected and the benchmark data collected by the project implementing agency (PIA) at the time of project planning were used for the study. All the collected data were analyzed through budgeting techniques or appropriate statistics. The cash flow table was developed which were further aggregated along with other miscellaneous costs of the project to generate total cost and benefit stream of the project. Results: The evaluation study reveals that runoff reduction of 8 to 10 percent and soil loss varies in the range of 1.1 to 1.9 t ha-1yr-1 after the project compare to 4.1 to 4.9 t ha-1yr-1 before the project shows the reduction of 3 t ha-1yr-1. Gully control structures made their impacts in terms of arresting silts at the rate of about 10.1 cum yr-1 in one watershed and stabilized the gullies. Increased water table in the range of 0.32 and 0.93 m with increased duration of water availability in wells for more than 9 months and increased recuperation rate (1.8 to 6.5 per cent) were observed. An additional surface storage capacity of 26.4 ha - m per watershed was created due to watershed interventions. The Net Present value of the project is about Rs. 52,238 lakhs without considering intangible benefits. The economic soundness of the project is also amply indicated by BCR (1.65:1) and IRR (53%) and the whole investment made in the project can be recovered within seven years. The NPV of the project further improved by inclusion of monetary value of the nutrient due to reduced soil erosion. The value of NPV was more than Rs. 63,968 Lakhs with 1.72 BCR and 65.5 % IRR. Conclusion: River valley project in South Pennaiyar catchment of Tamil Nadu is economically viable and recommended to be taken on priority for sustainable agricultural growth in the river / reservoir catchments.

The performance of an intercrop-based conservation bench terrace (CBT) system for controlling runoff and soil erosion and improving crop productivity in comparison to the conventional system of farming on sloping borders was evaluated in a sub-humid climate. Analysis of runoff and soil loss data revealed that the CBT system reduced runoff and soil loss by about 80% and 88%, respectively, compared to the conventional system, thus signifying a drastic reduction. The results of storm analysis suggest that the CBT system was very effective in reducing runoff and soil loss from storms of all sizes as compared to the conventional system. The major part of runoff (81.2%) in the conventional system was contributed by storms of less than 75 mm, whereas 88.8% of runoff in the CBT system was contributed by storms greater than 75 mm. The CBT system responded mainly to large storms due to the storage effects in the impoundment (recipient) area. The storage abstraction mechanism in the CBT system was further verified by event-based hydrograph analysis, drawing an inference that abstraction is a major factor in peak discharge attenuation due to storage routing. A comparison of the performance of an intercrop system with a monocrop system established the superiority of the former in reducing runoff and soil loss and improving crop productivity. The SCS curve number (CN) method was employed to standardize CN and initial abstraction values for both intercrop and monocrop based CBT and conventional systems. The initial abstraction term was estimated as 0.44 for CBT, as compared to 0.0156 for the conventional system of sloping borders. The CN values for intercrop-based CBT and conventional systems were estimated as 62 and 63, respectively, compared to 71 and 74 for monocrop-based systems. Predictive relationships between runoff and soil loss in both the CBT and conventional systems were established. The C factor of USLE was estimated as 0.31 and 0.28 for intercrop-based conventional and CBT systems, respectively, which can be utilized as a standard factor for estimation of soil loss for a system using USLE-based simulation modeling. Analysis of crop yield data revealed that the CBT system was about 18% more productive than the conventional system in terms of maize equivalent yields, primarily due to better in situ rainwater conservation. It is thus concluded that the intercrop-based CBT system is an economically viable alternative to the conventional system of sloping borders in conserving natural resources of soil and water and improving crop productivity in a sub-humid climate.

Soil and water are the most important natural resources that meet all human needs, and protect the environment and the civilization. Ever increasing demands for land and water resources due to burgeoning population cause the degradation of these two precious natural resources. Land degradation is a serious problem in India and out of 329 million hectare (Mha) of total geographical area, 146.8 Mha is reported as degraded. India is losing a huge amount of money in terms of loss of productivity from these degraded lands. Though India receives good amount of annual rainfall (1190 mm), due to enhanced need for domestic, agriculture and industrial developmental activities, over-exploitation and laxity of water resource, it becomes scarce. The declining trend of groundwater level in all parts of the country also indicates that the assured supply of good quality water will become a concern for country's development. Hence holistic management approach of soil and water resources by linking social and economic development with protection of natural ecosystem is the need of the hour. Creation of inventory on soil and water resources, use of modern technological tools for developing conservation strategies, changes in policy to protect natural resources, development of site specific soil and water conservation measures and involvement of local people in conserving the soil and water resources are the future challenges for the scientists and policy makers. This paper highlights the soil and water conservation strategies and areas to be addressed on priority.

Laboratory incubations were conducted to determine the ammonia (NH3) loss from urea as affected by the addition of coarse and ground (fine) pyrites at 1:1, 1:2 and 1:5 urea: pyrite (w/w) ratios and methods of application (surfaceapplication, incorporation and placement). Coarse pyrites (>-2mm) were not effective in reducing NH3 loss from urea when surface applied even at the highest ratio of pyrite (15.9% vs 18.7% without pyrite). Ground pyrites (0.1–0.25 mm), in 1:1 ratio, had about 5% less NH3 loss than the urea alone treatment. Higher ratios of pyrites reduced NH3 loss much more. Ammonia losses were the most with surface-applied urea (18.9%) and the least (13.5%) when placed (2.5 cm) below the soil surface. Addition of ground pyrite to surface-applied urea (1:1 ratio) decreased the loss to 13.2%. Urea+pyrite placed below the soil surface had the least loss (9.8%). Results indicate that combined application of urea and fine pyrite could reduce NH3 loss.

Growing of tea on sloping land without any soil and water conservation measures causes enormous soil loss especially in the initial years. For sound soil and water conservation planning, there is a need to evaluate the various conservation measures as related to the amount of expected runoff and soil erosion. In this context, a field study was conducted in the farmer's field in Nilgiris of South India, for evaluating the impact of farming methods on soil and water conservation efficiency under new tea plantation. One year old B-6 tea clones were planted at double hedge spacing (135 cm×75 cm×75 cm) in two slopes (8–12% and 30–35%) with treatments viz ., contour staggered trenches (CST), vegetative barrier (VB), CST alternate with VB, CST with cover crop of beans and farmers’ practice of plantation. Minimum runoff (14.6%) was observed from CST with cover crop of beans followed by CST (15.4%) under 8–12% slope range with exactly similar trend in runoff from the plots under 30–35% slope. Contrary to runoff, minimum soil loss was observed from CST (4.9 and 6.9 t ha −1 yr −1 ) followed by CST with cover crop of beans (5.3 and 7.3 t ha −1 yr −1 ) under 8–12% and 30–35% respectively. Implementation CST and CST with cover crop of beans are resulted in better soil moisture under both the slope ranges in comparison to remaining measures as well as farmers’ practice of plantation. Therefore, either CST alone or in combination with cover crop of beans are recommended for soil and water conservation under new tea plantation in the hill slopes.