1,169 research outputs found

    Optimal Provision and Finance of Ecosystem Services: the Case of Watershed Conservation and Groundwater Management

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    Payments for ecosystem services should be informed by how both the providing-resource and the downstream resource are managed. We develop an integrated model that jointly optimizes conservation investment in a watershed that recharges a downstream aquifer and groundwater extraction from the aquifer. Volumetric user-fees to finance watershed investment induce inefficient water use, inasmuch as conservation projects actually lower the optimal price of groundwater. We propose a lump-sum conservation surcharge that preserves efficient incentives and fully finances conservation investment. Inasmuch as proper watershed management counteracts the negative effects of water scarcity, it also serves as adaptation to climate change. When recharge is declining, the excess burden of non-optimal watershed management increases.Renewable resources, dynamic optimization, groundwater allocation, watershed conservation, multiple resource stocks

    Optimal Conjunctive Use of Groundwater and Recycled Wastewater

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    Inasmuch as water demand is multifaceted, infrastructure planning should be part of a general specification of efficient quantities and qualities of water deliveries over time. Accordingly, we develop a two-sector dynamic optimization model to solve for the optimal trajectories of groundwater extraction and water recycling. For the case of spatially increasing costs, recycled water serves as an intermediate resource in transition to the desalination steady state. For constant unit recycling cost, recycled wastewater eventually supplies non-potable users as a sector-specific backstop, while desalination supplements household groundwater in the steady state. In both cases, recycling water increases welfare by shifting demand away from the aquifer, thus delaying implementation of costly desalination. Implementation of the model provides guidance on the appropriate timing and size of backstop and recycling infrastructure as well as water deliveries from the various sources to the water-demand sectors.Renewable resources, dynamic optimization, groundwater allocation, wastewater reuse, recycling, reclamation, water quality

    Optimal and Sustainable Groundwater Extraction

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    With the specter of climate change, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is optimal. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climatechange specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.sustainability science, groundwater economics, dynamic optimization

    Ordering Renewables: Groundwater, Recycling, and Desalination

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    Optimal recycling of minerals can be thought of as an integral part of the theory of the mine. In this paper, we consider the role that wastewater recycling plays in the optimal extraction of groundwater, a renewable resource. We develop a two-sector dynamic optimization model to solve for the optimal trajectories of groundwater extraction and water recycling. For the case of spatially increasing recycling costs, recycled water serves as a supplemental resource in transition to the steady state. For constant unit recycling cost, recycled wastewater is eventually used as a sector-specific backstop for agricultural users, while desalination supplements household groundwater in the steady state. In both cases, recycling water increases welfare by shifting demand away from the aquifer, thus delaying implementation of costly desalination. The model provides guidance on when and how much to develop resource alternatives.Renewable resources, dynamic optimization, groundwater allocation, wastewater reuse, recycling, reclamation, water quality

    Sequencing Renewables: Groundwater, Recycled Water, and Desalination

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    Optimal recycling of minerals can be thought of as an integral part of the theory of the mine. In this paper, we consider the role that wastewater recycling plays in the optimal extraction of groundwater, a renewable resource. We develop a two-sector dynamic optimization model to solve for the optimal trajectories of groundwater extraction and water recycling. For the case of spatially increasing recycling costs, recycled water serves as a supplemental resource in transition to the steady state. For constant unit recycling cost, recycled wastewater is eventually used as a sector-specific backstop for agricultural users, while desalination supplements household groundwater in the steady state. In both cases, recycling water increases welfare by shifting demand away from the aquifer, thus delaying implementation of costly desalination. The model provides guidance on when and how much to develop resource alternatives.Renewable resources, dynamic optimization, groundwater allocation, wastewater reuse, recycling, reclamation, water quality, Environmental Economics and Policy, Resource /Energy Economics and Policy, Q25, Q28, C6,

    Attitudes toward Marriage, Divorce, Cohabitation, and Casual Sex among Working-Age Latinos: Does Religion Matter?

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    The rapid growth of the Latino population in the United States has renewed interest in Latino family research. It has often been assumed that Catholicism is a key factor influencing Latinos’ attitudes toward the family, despite the fact that nearly one third of Latinos are not Catholic. This article uses data from the 2006 National Survey of Religion and Family Life, a survey of working-age adults (aged 18-59 years) in the lower 48 states, to explore the relationship between multiple dimensions of religiosity—denomination, church attendance, prayer, and beliefs about the Bible—and Latinos’ attitudes regarding marriage, divorce, cohabitation, and casual sex. Compared with Catholics, evangelical Protestants tend to hold more conservative attitudes on family-related issues. Latinos who attend services regularly and pray frequently also report more traditional views. Findings involving literalist views of the Bible are more equivocal. Taken together, religious variables are just as potent as socioeconomic and demographic factors in explaining individual-level variation in Latinos’ attitudes. Study limitations are noted, and several directions for future research are identified

    Religion and Attitudes toward Same-Sex Marriage among U.S. Latinos

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    Objectives. This study examines links between multiple aspects of religious involvement and attitudes toward same-sex marriage among U.S. Latinos. The primary focus is on variations by affiliation and participation, but the possible mediating roles of biblical beliefs, clergy cues, and the role of religion in shaping political views are also considered. Methods. We use binary logistic regression models to analyze data from a large nationwide sample of U.S. Latinos conducted by the Pew Hispanic Forum in late 2006. Results. Findings highlight the strong opposition to same-sex marriage among Latino evangelical (or conservative) Protestants and members of sectarian groups (e.g., LDS), even compared with devout Catholics. Although each of the hypothesized mediators is significantly linked with attitudes toward same-sex marriage, for the most part controlling for them does not alter the massive affiliation/attendance differences in attitudes toward same-sex marriage. Conclusions. This study illustrates the importance of religious cleavages in public opinion on social issues within the diverse U.S. Latino population. The significance of religious variations in Hispanic civic life is likely to increase with the growth of the Latino population and the rising numbers of Protestants and sectarians among Latinos

    Islands of Sustainability in Time and Space

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    We review the economics perspective on sustainable resource use and sustainable development. Under standard conditions, dynamic efficiency leads to sustainability of renewable resources but not the other way around. For the economic-ecological system as a whole, dynamic efficiency and intergenerational equity similarly lead to sustainability, but ad hoc rules of sustainability may well lead to sacrifices in human welfare. We then address the challenges of extending economic sustainability to space as well as time and discuss the factors leading to optimal islands of preservation regarding renewable resources. Exogenous mandates based on moral imperatives such as self-sufficiency and strong sustainability may result in missed win-win opportunities that could improve both the economy and the environment, as well as increase social welfare across generations.Islands of sustainability, sustainable development, sustainability science, fisheries, forests

    outlook for fish to 2020

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    Fish trade ,Fisheries Economic aspects Developing countries ,Fisheries Environmental aspects ,

    Fish as food

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    "This paper reports results of incorporating fish into IMPACT, a global model of food supply and demand that estimates market-clearing prices to 2020 for 32 commodities in 36 regions. It summarizes results for production, consumption, net exports and real price changes for 10 economic categories of fisheries items, disaggregated into 15 geographic regions of the world. Under the medium-variant scenario for the uncertain capture fisheries sectors, global production of food fish is projected to rise by 1.5% annually through 2020, with two-thirds of this from aquaculture, whose share in total food fish production rises to 41%. Global per capita fish consumption is projected to be 17.1 kg in 2020, with sensitivity analysis indicating a margin of 2 kg/capita either way based on extreme scenarios for capture and aquaculture. Most growth will occur in developing countries, which will account for 79% of food fish production in 2020. China's share of world production will continue to expand, while that of Japan, the EU, and former USSR will continue to contract. Real fish prices will rise 4 to 16% by 2020, while meat prices will fall 3%. Fishmeal and oil prices will rise 18%; use of these commodities will increasingly be concentrated in carnivorous aquaculture. Growing domestic demand will dampen fish exports from developing countries. Sensitivity analysis incorporating a very pessimistic view of capture fisheries leads to escalating food fish prices (+69% for high-value finfish) and soaring fishmeal prices (+134%), whereas an optimistic view of increased investment in aquaculture lowers real prices of low value food fish (-12%), and raises fishmeal prices (+42%)." Authors' AbstractFishery production Forecasting ,Food supply ,
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