Until recently, aquifers located in hard rock formations (granite, gneiss, schist) were considered as a highly heterogeneous media, and no adequate methodology for groundwater management was available. Recent research studies have shown that when hard rocks are exposed to regional and deep‐weathering processes and when the geology is relatively homogenous, a typical hard rock aquifer is made of two main superimposed hydrogeological layers each characterized by quite homogeneous specific hydrodynamic properties: namely the saprolite and the fissured layers. Therefore, for these cases, hard rock aquifers can be considered as a multi‐layered system. Based on these works, an operational decision support tool (DST‐GW) designed for the management of groundwater resources in hard rock area under variable agro‐climatic conditions has been developed. The tool focuses on the impact of changing cropping pattern, artificial recharge and rainfall conditions on groundwater levels at the scale of small watersheds (10 to about 100 km2 in case well‐developed weathering profile). DST‐GW is based on the groundwater balance and the ‘water table fluctuation method’, which are well‐adapted methods in hard rock and semi‐arid contexts. Based on field data from an overexploited South Indian watershed (58 km2), the model allows calibrating, at watershed scale, the variation in specific yield of the aquifer with depth, as well as the rainfall‐aquifer recharge relationship. Seasonal basin‐scale piezometric levels are computed with an average deviation of ± 0·56 m compared to measurements from 2001 to 2005. The model shows that, if no measure is taken, the water table depletion will induce the drying‐up of most of the exploited borewells by the year 2012. Scenarios of mitigation measures elaborated with the tool show that change in cropping patterns could rapidly reverse the tendency and lead to a sustainable management of the resource. This work presents the developed tool and particularly the hydraulic model involved in and its application to a case study. However, the purpose tool is applicable at watershed scale but not design for the groundwater management of a very small area or for a single borewell. Copyright © 2010 John Wiley & Sons, Ltd.

SUMMARYProjections suggest that annual per capita water availability in the Indo-Ganga Basin (IGB) will reduce to a level typical for water-stressed areas. Producing more crop and livestock products, per unit of agricultural water invested, is advocated as a key strategy for future food production and environmental security in the basin. The objective of this study was to understand the spatio-temporal dynamics of water requirements for livestock feed production, attendant livestock water productivity (LWP) and implications for the future sustainable use of water resources. We focused on three districts in the IGB representing intensive (higher external inputs, e.g. fertilizer, water) and semi-intensive (limited external input) crop-livestock systems. LWP is estimated based on principles of water accounting and is defined as the ratio of livestock beneficial outputs and services to the water depleted and degraded in producing these. In calculating LWP and crop water productivity (CWP), livestock, land use, land productivity and climatic data were required. We used secondary data sources from the study districts, field observations and discussions with key informants to generate those data sets. Our result showed that the volume of water depleted for livestock feed production varied among the study systems and was highly affected by the type of feed and the attendant agronomic factors (e.g. cropping pattern, yield). LWP value was higher for intensive systems and affected by agricultural water partitioning approaches (harvest index, metaolizable energy). LWP tended to decrease between 1992 and 2003. This can be accounted for by the shift to a feeding regime that depletes more water despite its positive impacts on animal productivity. This is a challenging trend with the advent of and advocacy for producing more agricultural products using the same or lower volume of water input and evokes a need for balanced feeding, by considering the nutritive value, costs and water productivity of feed, and better livestock management to improve LWP.

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This paper reviews water institutional reforms in Sri Lanka by contrasting those observed during the 1980s with those proposed during the 1990s. While the earlier reforms focused on the irrigation sector that yielded quicker benefits and low political risks, recent reforms have covered macro institutions and the whole water sector where the benefits are gradual and less visible but with high political risks. As the earlier reforms were packaged as part of larger investment programs, they had in-built incentives and strong proponents. But recent reforms not only lacked such conditions but also faced an ideologically charged hostile environment. Despite the current failure of the reforms, their future prospect is not that bleak in view of the emerging consensus on most issues and the continuing government commitment to reform. The Sri Lankan case also provides evidence for the effects of transaction cost and political economy factors, the tactical benefits of reform packaging, sequencing and timing, and the role of stakeholders' perception, learning and information in articulating the demand for change.

The paper discusses the contribution of crop residues (CR) to feed resources in the context of the water productivity of CR in livestock feeding, using India as an example. It is argued that crop residues are already the single most important feed resource in many livestock production systems in developing countries and that increasing their contribution to livestock feeding needs to be linked to improving their fodder quality. Using examples from multi-dimensional crop improvement, it is shown that CR fodder quality of key crops such as sorghum, rice and groundnut can be improved by genetic enhancement without detriment to grain and pod yields. Improving crop residue quality through genetic enhancement, agronomic and management interventions and strategic supplementation could improve water productivity of farms and systems considerably. The draw-backs of CR based feeding regimes are also pointed out, namely that they result in only moderate levels of livestock productivity and produce higher greenhouse gas emissions than are observed under feeding regimes that are based on high quality forages and concentrates. It is argued that feed metabolisable energy (ME) content should be used as an important determinant of livestock productivity; water requirement for feed and fodder production should be related to a unit of feed ME rather than feed bulk. The paper also revisits data from the International Water Management Institute (IWMI) work on livestock–water productivity in the Indian state of Gujarat, showing that water input per unit ME can vary several-fold in the same feed depending on where the feed is produced. Thus, the production of one mega joule of ME from alfalfa required 12.9 L of irrigation-derived water in south Gujarat but 50.7 L of irrigation-derived water in north Gujarat. Wheat straw in south Gujarat required 20.9 L of irrigation-derived water for 1 MJ ME and was in this instance less water use efficient than alfalfa. We conclude that water use efficiency across feed and fodder classes (for example crop residue v. planted forages) and within a feed is highly variable. Feeding recommendations should be made according to specific water use requirement per unit ME in a defined production system.

This paper presents an overview of the theoretical, methodological and policy issues that are evident both in the extant literature on the subject as well as in the set of papers that are included in this special issue. In providing such an overview, this paper also develops an analytical framework using a schematic representation of some of the most important layers and pathways that underlie the water-poverty-gender nexus. Based on the overview and discussion, this paper attempts: (a) to indicate approaches and strategies for using water as a key instrument to address poverty and gender concerns and (b) to identify the research gaps in order to set the direction for ongoing and future research at the water-poverty-gender interface.

SUMMARYThe concept of water productivity (WP) or ‘more crop per drop’ has been revived recently in international water debates. Its application has notably been extended from single crops to mixed farming systems, integrating both crops and livestock, with the wider objective of reducing poverty. Using evidence from the Ganga Basin, India, we discuss the relevance of this concept as a tool to guide interventions for livelihood improvement and poverty alleviation. We argue that WP studies would benefit from greater attention to the role of capitals, inequities and institutions. Firstly, it is crucial to acknowledge the heterogeneity of capitals and capabilities of farmers to make changes in their farming systems and practices and avoid one-fix-all interventions. Identifying pre-existing inequities in water access within and among communities will support better targeting of poor communities. WP interventions can either reinforce or reduce inter-household inequities within communities. We stress the need for assessment of institutional impacts of WP interventions on water access and development.

IntroductionIn the 1950s and 1960s, there was significant global concern over the capacity of agricultural production systems to produce enough food for rapidly growing populations, especially in developing countries. Episodes of severe food scarcity were frequent, especially in the populous countries of southern Asia. The world community responded to the perceived threat in various ways. A major strategy was the rapid creation of new irrigation schemes. These efforts reached a peak in the mid-1970s, when the world's stock of irrigated land was increasing by about 2.5 percent per annum 2 . Many irrigation facilities were planned, constructed, and managed by the government. Invariably, farmers were not consulted in the design or the management of the irrigation facilities. There is clear evidence to show that the spread of irrigation has been a major contributor to the success of the green revolution in Asia and the remarkable increases in agricultural output. By the early 1980s, however, there was widespread dissatisfaction with the performance of irrigation projects, particularly in the large government-managed canal systems, casting doubts on the efficacy of bureaucratic management in the irrigation sector. The 1980s saw the beginning of a search for a new type of relationship between the managers of the irrigated agriculture sector and farmers. With regard to irrigation, this trend led to efforts to promote a participa- REVIEW AbstractParticipatory irrigation management (PIM) is an approach in which farmers participate in all stages of irrigation development through to operation and maintenance, and is implemented in many developing countries. Irrigation management transfer (IMT), a program of transferring the management of irrigation system from government to local user groups, has also been promoted. However, in most cases these approaches have not been successful, because, for example, of the unfair cost sharing and financial weakness in farmers' organizations. This paper summarizes the current problems of PIM/IMT, proposes basic principles for sustainable PIM, which can be applied to IMT, through a review of the previous studies, and discusses future areas for the sustainable use and management of irrigation systems. The key issues that have contributed to the failure of PIM/IMT are a lack of awareness among farmers of the role and necessity of water users' associations (WUA) and the inherent weakness of WUA. We propose the following principles for functional sustainable irrigation management: (1) The roles of WUA and governance are clear and adequate; (2) Through participation in WUA, farmers are guaranteed that their demand for water is supplied in a timely manner; (3) Farmers receive financial benefits through the use of water, which then allows them to cover the costs of water and associated services; (4) All members are treated equally with respect to water allocation, cost sharing, and decision-making; and (5) Information on the financial status and transactions are disclosed to members of WUA in a...