DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.Resource /Energy Economics and Policy,

Flexible strategies for coping with rainfall variability: seasonal adjustments in cropped area in the Ganges basin

This work was partly carried out by the Himalayan Adaptation, Water and Resilience (HIAWARE) consortium under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA). Under this initiative, CS and HB received financial support from the UK Government’sDepartment for International Development and the International Development Research Centre, Ottawa, Canada. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.One of the main manifestations of climate change will be increased rainfall variability. How to deal with this in agriculture will be a major societal challenge. In this paper we explore flexibility in land use, through deliberate seasonal adjustments in cropped area, as a specific strategy for coping with rainfall variability. Such adjustments are not incorporated in hydro-meteorological crop models commonly used for food security analyses. Our paper contributes to the literature by making a comprehensive model assessment of inter-annual variability in crop production, including both variations in crop yield and cropped area. The Ganges basin is used as a case study. First, we assessed the contribution of cropped area variability to overall variability in rice and wheat production by applying hierarchical partitioning on time-series of agricultural statistics. We then introduced cropped area as an endogenous decision variable in a hydro-economic optimization model (WaterWise), coupled to a hydrology-vegetation model (LPJmL), and analyzed to what extent its performance in the estimation of inter-annual variability in crop production improved. From the statistics, we found that in the period 1999–2009 seasonal adjustment in cropped area can explain almost 50% of variability in wheat production and 40% of variability in rice production in the Indian part of the Ganges basin. Our improved model was well capable of mimicking existing variability at different spatial aggregation levels, especially for wheat. The value of flexibility, i.e. the foregone costs of choosing not to crop in years when water is scarce, was quantified at 4% of gross margin of wheat in the Indian part of the Ganges basin and as high as 34% of gross margin of wheat in the drought-prone state of Rajasthan. We argue that flexibility in land use is an important coping strategy to rainfall variability in water stressed regions

Interplay between land-use dynamics and changes in hydrological regime in the Vietnamese Mekong Delta

Policies supporting rice production and investments in water infrastructure enabled intensification and diversification of farming systems in the Vietnamese Mekong Delta (VMD) over the past 20 years. Yet, demands of food security, economic development, and climate change continue to pose diverging and often conflicting challenges for water resources management in the upper, central, and coastal zones of the delta. The major changes effected in the VMD’s hydrological regime and land-use patterns are acknowledged in the literature, but few studies have examined the interplay between these dynamics at the delta scale. Based on time-series maps and statistical data on land-use, flooding, and salinity intrusion, we investigated the interrelations between land-use dynamics and changes in hydrological regime across the VMD in three representative periods. Land-use was found to be highly variable, changing by 14.94% annually between 2001 and 2012. Rice cropping underwent the greatest change, evolving from single cropping of traditional varieties towards double and triple cropping of high-yielding varieties. Aquaculture remained stable after rapid expansion in the 1990s and early 2000s. Meanwhile, flooding and salinity intrusion were increasingly controlled by hydrological infrastructure erected to supply freshwater for agriculture. Effects of this infrastructure became particularly evident from 2001 to 2012. During this period, spatial and temporal impacts on flooding and salinity intrusion were found, which extended beyond the rice fields to affect adjacent lands and livelihood activities. Unforeseen effects will likely be aggravated by climate change, suggesting a need to rethink the scale of planning towards a more integrated hydrologic approach

Water Pricing and Valuation in Indonesia: Case Study of the Brantas River Basin

The increasing demand for water and limited degree of cost recovery for irrigation water delivery are important challenges for policymakers in Indonesia. To meet the increasing demand for water, it is important to reduce water use in irrigated paddy cultivation, long the dominant consumptive user, and to divert water away from agriculture to domestic and industrial sectors. Reducing water use in irrigated agriculture can be achieved through various means, including rationing, improved user management, and water markets. The appropriate method depends on the situation specific to each basin. In the Brantas Basin in East Java, rationing is already practiced, but often leaves the non-licensed, (non-paying) irrigators with insufficient supplies. Moreover, very low irrigation service fee recovery rates hamper ongoing water sector reforms, which seek to strengthen the capacity of local institutions to co-manage water resources. In the Brantas Basin the average value of water in the production of important irrigated crops substantially exceeds estimated water supply costs and current ISF. However, increased water use fees would impose a substantial burden on farm economic welfare, while water savings would be relatively modest. Therefore, to conserve water and enhance the financial autonomy of irrigators alternative management systems are proposed, including ‘Integrated Crop and Resource Management’ and a water brokerage mechanism

WATER AS AN ECONOMIC GOOD IN IRRIGATED AGRICULTURE: THEORY AND PRACTICE

This report describes the results of the Water Valuation and Pricing project, which aims to provide insight into the relevance of economics to typical problems found in irrigated agriculture. It first considers the theoretical basis for the use of economic instruments, then considers their usefulness in the context of five case studies of irrigated areas - in Egypt, India, Indonesia, Morocco and Ukraine. The case studies confirm that competition for scarce water and shortage of funds are widespread. The study provides insight into the current price paid for water, the cost of service provision, and the value to irrigators of the water they receive. The analysis shows that volumetric pricing is unlikely to be relevant to demand management because the price of water at which demand and supply would be balanced is so high as to substantially reduce farm incomes. This socio-political problem, plus the technical and administrative complexity of measuring and accounting for water, and the crucial distinction between water applied to the field and water consumed by the crop make water pricing an unsuitable approach to balancing supply and demand

WATER AS AN ECONOMIC GOOD IN IRRIGATED AGRICULTURE: THEORY AND PRACTICE

This report describes the results of the Water Valuation and Pricing project, which aims to provide insight into the relevance of economics to typical problems found in irrigated agriculture. It first considers the theoretical basis for the use of economic instruments, then considers their usefulness in the context of five case studies of irrigated areas - in Egypt, India, Indonesia, Morocco and Ukraine. The case studies confirm that competition for scarce water and shortage of funds are widespread. The study provides insight into the current price paid for water, the cost of service provision, and the value to irrigators of the water they receive. The analysis shows that volumetric pricing is unlikely to be relevant to demand management because the price of water at which demand and supply would be balanced is so high as to substantially reduce farm incomes. This socio-political problem, plus the technical and administrative complexity of measuring and accounting for water, and the crucial distinction between water applied to the field and water consumed by the crop make water pricing an unsuitable approach to balancing supply and demand.Resource /Energy Economics and Policy,

Water pricing in Tadla, Morocco

In Molle, Francois; Berkoff, J. (Eds.). Irrigation water pricing: the gap between theory and practice. Wallingford, UK: CABIComprehensive Assessment of Water Management in Agriculture Series

Water pricing in Haryana, India

In Molle, Francois; Berkoff, J. (Eds.). Irrigation water pricing: the gap between theory and practice. Wallingford, UK: CABIComprehensive Assessment of Water Management in Agriculture Series

Assessing the economic impact of redistributing water within a catchment: A case study of the Musi Catchment in the Krishna Basin in India

The aim in this paper was to present the details of an economic modeling exercise conducted on the Musi Catchment of the Krishna Basin. The model has the unique characteristic of being able to value the water used on individual crops and in different regions. Thus, the individual values of water used to produce different crops, grown over two different seasons and over five very different regions within a catchment, were determined. This is a significant improvement over previous attempts, where a single value of water in a catchment was derived regardless of what it is used for, when it was used and where it used in the catchment. In addition to the agricultural valuation process, some account was made for the other uses of water and how they should be valued. The worth of these findings cannot be underestimated as the results are useful to those who need to allocate scarce water supplies between competing uses within a catchment. The assumptions underlying the model, the data used and the results and implications drawn are fully detailed in this paper. This model was connected to a hydrological model and used to simulate various scenarios on the water situation facing users in the basin. This model is the forerunner of similar modeling attempts on similar problems in other regions of the Krishna Basin and in the Murray Darling Basin of Australia

DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality