Process and Mechanism of Agricultural Irrigation Benefit Allocation Coefficient Based on Emergy Analysis—A Case Study of Henan, China

The progressive development of the agricultural production system is the foundation for promoting the rapid and efficient growth of the regional economy. In this study, the irrigation benefit allocation coefficient for the agricultural irrigation system of Henan Province from 1999 to 2014 was comprehensively investigated on the basis of the theory of emergy analysis. The process and mechanism of the variation coefficient were explored using ArcGIS 10.1 (Environmental System Research Institute, Redlands, USA) and SPSS 21.0 software (IBM, Chicago, USA), and the results were shown spatially. From the analysis and results, the emergy investment and yield in the Henan agricultural production system were found to continuously increase with annual increases of 2.26% and 4.22%, respectively. However, the irrigation benefit allocation coefficient of Henan showed a continuous downward trend with a total decrease of 0.026 due to precipitation. The irrigation benefit allocation coefficient fluctuated owing to the combined influence of multiple restraining factors, among which chemical fertilizers and pesticides played the dominant role. Therefore, comprehensive application of multiple emergy investment methods was critical for boosting emergy yield.

Evaluating a Water Conservation Response to Climate Change in the Lower Boise River Basin

Aquifers created or sustained by seepage losses from Bureau of Reclamation (Reclamation) Projects extend over vast areas of western states. Yet agricultural water conservation measures such as canal lining top the list of State and Federal policies for mitigating the effect of water shortages brought about by climate change. Cost benefit analysis (CBA) of new Reclamation water conservation infrastructure such as canal lining or piping is too often Project-specific, and detached from basin hydrology. The value of canal seepage as a positive externality is thus ignored in CBA. A basin-wide approach to hydro-economic modeling that accounts for the externalized costs and benefits of both canal seepage and new canal lining conservation insures that incidental aquifer recharge is recognized in CBA of Federally financed irrigation water conservation measures. Integrated hydrologic and partial equilibrium models are employed in the Lower Boise River basin to calculate the foregone benefit to non-project groundwater and drain water irrigation of a hypothetical Boise Project canal lining response to projected climate change water shortages. Basin-wide hydrologic response data is used to compute shifts in non-project groundwater supply functions and drain water supply constraints, and a base-case water supply scenario is compared to six climate change scenarios in which projected water shortages are offset by lining of project canals. The foregone net benefit to non-project groundwater and drain water irrigation resulting from elimination of the canal seepage externality (US$[Formula: see text]4.4–22.6[Formula: see text]million depending on the scenario) outweighs the increase in net benefit to Boise Project irrigation by canal lining (US$[Formula: see text]1.4–19.3[Formula: see text]million). On average, foregone groundwater and drain water irrigation benefit exceeds restored canal irrigation benefit by about 38%. Canal lining conservation is unable to restore total basin-wide irrigation net benefit to the base-case level in any of the climate change scenarios; rather it shifts the foregone benefit of climate change shortages from project canal irrigation to non-project groundwater and drain water irrigation. The canal lining CPA is not a complete accounting of either costs or benefits of canal lining conservation. On the cost side, only the foregone benefits of eliminating the positive canal seepage externality are calculated; construction and maintenance costs of canal lining are omitted. On the benefit side, Arrowrock canal irrigators are assumed to be the sole beneficiary of reduced seepage losses.

Marginal benefit based optimal water allocation: case of Teesta River, Bangladesh

This article describes a hydrologic–economic optimization model for allocating available river flow between competing off- and in-stream demands, based on the marginal benefits (MBs) of sectoral water uses in a segment of the Teesta River in Bangladesh. Irrigation, capture fishery and navigation are the main direct water uses considered. The value of irrigation water was estimated using the residual imputation method. Losses in yield caused by lowered irrigation supply, resulting from reduced river flow, formed the basis for establishing the total and MB functions for off-stream river water use (irrigation). Total and MB functions for in-stream water use (capture fishery, navigation) were developed using field survey data of beneficiaries' income as a function of river flow. Analysis was enhanced by applying AQUARIUS, which allocates water between users to maximize consumer surplus based on MB functions. Model results show that in-stream uses could not compete with off-stream uses in the case of the Teesta, as substantial benefit was obtained from irrigation. Environmental flow to safeguard river health and in-stream use was considered to be a constraint in the optimization, which results in a sizeable reduction in irrigation benefit with a small increase in in-stream benefit. The necessary trade-offs between economic efficiency and environmental protection are depicted, providing insight into a justifiable water allocation strategy for the Teesta.

Maximizing Benefits from Hydropower: A Nepal Case

Hydropower development is the only development activity that yields multiple benefits and, in many cases, can be an effective agent for poverty alleviation. Apart from being a source of renewable and clean energy, to stabilize the supply of electricity, it helps provide year round irrigation resulting in the increase in the cropping intensity and changing cropping pattern, and it reduces both deforestation and greenhouse gas (GHG) emissions. Nepal has adopted a policy of Integrated Water Resources Management (IWRM), by which hydropower projects are developed in conjunction with irrigation, flood control, water supply and navigation components whenever feasible. As an agriculture dependent country, Nepal should maximize the irrigation benefit, by providing year round irrigation through storage projects developed for peak energy generation. Nepal has planned to provide year round irrigation to 67% of the total irrigated area by 2027. Electricity from hydropower projects currently contributes only 1% of energy need, whereas fuelwood contributes 68%, and fossil fuels 8%. Development of hydropower not only helps reduce deforestation, reported at the rate of 0.7% per annum, but also helps reduce GHG emission by substitution of imported fossil fuels. The annual fossil fuel import bill for Nepal 2004/05 was about 310 million USD. Nepal could benefit substantially if consumption of petroleum products were replaced by hydropower. Where the Clean Development Mechanism (CDM) is effectively used to address the impact on climate change, hydropower gains significance in contributing positively to climate change. Key words: Hydropower, IWRM, maximization of benefit, poverty alleviation, growth, Nepal Hydro Nepal: Journal of Water, Energy and Environment Vol. I, Issue No. 1 (2007) pp. 29-34