Water resources management in developing countries: The role of hydrology - economic modelling

[摘要] Hydrology - economic modelling is common in water resources management, and has been well reviewed in the literature. However, the particular requirements of the developing world appear not to have been described. We contend that there are significant differences in some aspects of modelling for the developing world, including greater emphasis on food security, poverty alleviation, economic development and equitable allocations, with lesser attention to issues such as the environment, markets and profits.Hydrology - economic models vary greatly in their approach to modelling, from hydrology models with only a weak expression of the economics to economic models with weak hydrology. Some models have the hydrology and economic components fully integrated in a single program, whereas others have separate loosely coupled models (sometimes manual passing of data). The hydrology component of models varies from simple water balances to sophisticated and numerically intensive river and groundwater models. The economics components of models include optimisation (what is best?), simulation (what if?), benefit-cost analyses and value of water assessment. They vary from single sector to whole economy, and from single year to multi-year. Integrating the hydrology and economic components is challenging, with different time and spatial scales of the hydrology and economic processes and often limited data. Many approaches have been taken to dealing with the challenges. We list 47 papers that describe the application of hydrology - economic models in the developing world.Economic models may be short run models, in which production changes temporarily in response to a short term constraint, such as a drought. Other models are long run models, in which production changes permanently in response to a long term change, such as the building of new dams or irrigation areas, or climate change. The distinction between the two is not clear in many applications, with models with short run constraints being applied to assess long run effects.The food security imperative in the developing world suggests that a greater focus should be placed on developing models that minimise (or simulate decisions about minimising) risks in food production rather than net agricultural benefits. A few models do simulate risk aversion, but the consequences seem largely unexplored in the literature. The distinction between short run and long run models is often not clear with apparently short run constraints and assumptions sometimes used to model long run effects.Water resources in the Indus Basin are amongst the most stretched in the world, and likely to become more stretched with population growth and climate change. Furthermore, there is a perceived need for more up to date modelling of water resources. We therefore use the Indus Basin as a case study to examine the needs and current state of modelling.Pakistan has a great many water challenges arising from the limited supply per capita (of less than 1100 m3 per person annually), the over-exploitation of groundwater, resource degradation due to salinity, flooding and drainage woes, low water productivity in agriculture and a poor knowledge base. The main water policy goals in Pakistan are designed to address the challenges and include providing adequate and safe drinking water, providing food security, developing hydropower for economic growth, mitigating floods and minimising flood damage, maintaining water quality and enhancing the environment. Policies to support the goals include conservation of both surface water and groundwater resources, increasing the efficiency of use particularly in agriculture, development of more water storage, water treatment and reuse, various water institutional reforms, the continuing need for transboundary cooperation on water resources and resolving interprovincial mistrust on water sharing.The challenges and policy goals point to a clear need for better river and groundwa...

[发布机构] CSIRO

[学科分类] 地球科学(综合)