Effects of instantaneous groundwater availability on irrigated agriculture and implications for aquifer management

Groundwater is an important input for agricultural production in many parts of the world. Aquifer depletion has been shown to affect the rate that groundwater can be extracted from an aquifer. In this paper, we develop an analytical framework that accounts explicitly for the effects of limited instantaneous groundwater extraction rate (well capacity) on a producer's irrigation decisions. We show that limited well capacities can affect the producer’s groundwater use and profit. We draw three important insights from these findings. First, we demonstrate that the price elasticity of demand for groundwater is higher for lower well capacities. Second, farmers’ irrigation decisions are non-monotonic with respect to well capacity and climate conditions. Under a drier climate, producers with greater well capacities increase their groundwater use, and producers with lower well capacities reduce their water use. Third, through numerical analysis, we show that considering spatial heterogeneity in well capacities is important for estimating the cost-effectiveness and distributional impacts of groundwater management policies. Our results shed new light on the importance of extraction capacity for groundwater management policies and the potential impacts of climate change on agricultural production.     

Enhanced Geospatial Validity for Meta-analysis and Environmental Benefit Transfer: An Application to Water Quality Improvements

Meta-regression models are commonly used within benefit transfer to estimate willingness to pay (WTP) for environmental quality improvements. Theory suggests that these estimates should be sensitive to geospatial factors including resource scale, market extent, and the availability of substitutes and complements. Valuation meta-regression models addressing the quantity of non-market commodities sometimes incorporate spatial variables that proxy for a subset of these effects. However, meta-analyses of WTP for environmental quality generally omit geospatial factors such as these, leading to benefit transfers that are invariant to these factors. This paper reports on a meta-regression model for water quality benefit transfer that incorporates spatially explicit factors predicted by theory to influence WTP. The metadata are drawn from stated preference studies that estimate per household WTP for water quality changes in United States water bodies, and combine primary study information with extensive geospatial data from external sources. Results find that geospatial variables are associated with significant WTP variations as predicted by theory, and that inclusion of these variables reduces transfer errors.     

Hydro-economic river basin modelling: The application of a holistic surface-groundwater model to assess opportunity costs of water use in Spain

Combined hydro-economic models of river basins are fundamental tools for assessing management and infrastructure strategies to improve the economic efficiency of water use in a context of competition over scarce water resources. Integrated hydro-economic models have to be capable to properly reproduce the physical behavior of the system, with a realistic representation of the different surface and groundwater resources, including their interaction, and the spatial and temporal variability of resource availability. On the other hand, such models must incorporate the value of water for different urban, agricultural and industrial uses and users. Economic values for water use are defined according to the marginal residual value of water for production (for agricultural and industrial uses) or the aggregated willingness-to-pay (WTP) for urban supply and other final water uses. In this paper, we present a systematic approach to estimate the marginal economic value of surface and groundwater resources at different locations within a complex water resources system. Based on a holistic conjunctive optimization model applied to the Adra river system in Spain we asses the total and marginal opportunity costs of capacity and operation constraints, including the opportunity cost of imposing environmental constraints on water use as foreseen in future Spanish water policy following the implementation of the European Water Framework Directive. The resulting opportunity costs provide important information to water managers about economic inefficiencies of current water allocation policy or infrastructure design, and about the resource opportunity costs to be considered in the design of efficient pricing policies in regions with water scarcity issues.     

Integrating public demands into model-based design for multifunctional agriculture: An application to intensive Dutch dairy landscapes

The contribution of agriculture to the welfare of society is determined by its economic, social and environmental performance. Although theoretical discussions can be found in the literature, few reports exist that integrate the social demand for multifunctional agriculture in the evaluation of the sustainability and the global welfare of society. This paper presents a methodology that combines economic valuation, integrated modelling, stakeholder analysis, and multi-criteria evaluation. It consists of three steps to determine: (1) social demands for multifunctional agriculture; (2) feasible technical alternatives available from the supply part of the market; (3) the net utility of alternatives for society measured as the change in social net benefit, i.e. the sum of changes compared to the current situation expressed in utility of market and non-market net benefits. Market net benefits are represented by their monetary value. Quality Function Deployment combined with Analytic Network Process (QFD/ANP) were used to estimate the non-market net benefits. The methodology is applied to the case study of a dairy-farming based agricultural landscape in the Northern Friesian Woodlands, The Netherlands. Social net benefit depended on land use, i.e. pasture management regimes on each of the agricultural fields and on presence or absence of hedgerows around the fields. Changes in market net utility were expressed in terms of changes for farmers, consumers and government. Changes in non-market net utility were expressed in terms of changes in landscape quality, nature value and environmental health for Dutch society as a whole, as estimated from European public surveys (Eurobarometer). The complete solution space defined by the market and non-market net benefits of landscapes with alternative patterns of land use was estimated to offer insight in the trade-off between market and non-market performance and enable selection of ‘icon’ landscapes to target or avoid. Improvement of the current landscape towards the social optimum would involve changes in pasture management resulting in higher gross margin for farmers, slightly relaxing current environmental restrictions, which could be reached at lower levels of subsidies in agri-environmental programs. In addition to such overall optimum the results demonstrate the trade-off between market and non-market benefits and the characteristics of current, utopian and dystopian landscapes. The approach provides an alternative to current economic valuation methods which focus on assessment of economic value as an input to analysis. Here, economic value emerges as the trade-off between market and non-market functions which is an output of the analysis.     

On the spatial nature of the groundwater pumping externality

Most existing economic analyses of optimal groundwater management use single-cell aquifer models, which assume that an aquifer responds uniformly and instantly to groundwater pumping. In this paper, we develop an economic model of groundwater management that explicitly incorporates spatial dynamic groundwater flow equations. Calibration of our model to published economic studies of specific aquifers demonstrates that existing studies generally incorrectly estimate the magnitude of the groundwater pumping externality relative to spatially explicit models. In particular, for large aquifers with surface areas of thousands of square miles, the marginal pumping externality predicted by single-cell models may be orders of magnitude less than that predicted by a spatially explicit model, even at large distances from a pumping well. Conversely, for small aquifers with areas of a few hundred square miles or less, single-cell models reasonably approximate the pumping externality. Application of single-cell models to inappropriate settings may result in misleading policy implications due to understatement of the magnitude and spatial nature of the groundwater externality.     

Willingness to Pay for Ancillary Benefits of Climate Change Mitigation

Assessing the Willingness to Pay (WTP) of the general public for climate change mitigation programmes enables governments to understand how much taxpayers are willing to support the implementation of such programs. This paper contributes to the literature on the WTP for climate change mitigation programmes by investigating, in addition to global benefits, the ancillary benefits of climate change mitigation. It does so by considering local and personal benefits arising from climate change policies. The Contingent Valuation Method is used to elicit the WTP for ancillary and global benefits of climate mitigation policies in the Basque Country, Spain. Results show that WTP estimates are 53–73% higher when ancillary benefits are considered.     

Choosing Between Internet and Mail Survey Modes for Choice Experiment Surveys Considering Non-Market Goods

In a choice experiment setup considering a non-market good, this paper adds to the literature on survey mode effects by providing evidence that internet surveys can be a viable alternative to traditional mail surveys when gathering feedback from a sample of respondents. The case study concerns preferences for protecting different types of landscape from road encroachment when building new motorways in Denmark. Two samples of respondents are surveyed—one by internet and one by mail. The performances of the two samples are compared over six different criteria; response rates, protest responses, demographics, preferences and WTP, estimation precision, and, finally, certainty in choice. Differences are observed for some of these criteria, implying that analysts should be aware that choosing internet over mail could be accompanied by a survey mode effect. However, the observed differences do not translate into significant differences in the unconditional WTP estimates. In most applied economic valuation studies of non-market goods, the main objective is in fact estimation of WTP. Hence, in the present case, the identified survey mode effects do not severely invalidate the applicability and continued use of the internet as a suitable means of collecting data for choice experiment economic valuation of non-market goods.     

Economic valuation of environmental services sustained by water flows in the Yaqui River Delta

We attempted to estimate the economic value of environmental services provided by restored instream flows in the water-scarce Yaqui River Delta in Mexico. The Yaqui River begins near the U.S.-Mexico border and continues for 400 km before reaching the Oviachic dam, but has not reached the nearby Gulf of California for decades due to diversions for irrigation. These diversions have degraded the riparian ecosystem, coastal wetlands, and estuaries. Environmental services provided by restored flows in the Yaqui River would include healthy riverside vegetation, wetlands and estuaries, fish and wildlife habitats, non-use values, and recreation. A contingent valuation survey in 40 neighborhoods in the most populated Delta city, Ciudad Obregon, was administered to estimate non-market values of instream uses. Respondents were given a current and hypothetical Delta scenario (the latter assumed restored water flows in the River) and asked a willingness-to-pay (WTP) question regarding purchasing water for environmental flows through higher water bills. Results from 148 in-person interviews indicated that households would pay an average of 73 pesos monthly. WTP was found related to key variables suggested by economic theory and contingent valuation studies elsewhere: income, educational level, number of children in the household, and initial bid amount. These results will allow decision makers to compare the benefits generated by different water uses, including environmental services, and to manage scarce water resources under a long-term sustainable approach.     

Converting Forests to Farms: The Economic Benefits of Clearing Forests in Agricultural Settlements in the Amazon

Agricultural expansion into tropical forests is believed to bring local economic benefits at the expense of global environmental costs. The resulting tension is reflected in Brazilian government policy. The national agrarian reform program has settled farm families in the Amazon region since the 1970s, with the expectation that they will clear forests in order to farm the land. On the other hand, recent Brazilian policy initiatives seek to reduce deforestation to mitigate climate change. We contribute to the policy debate that surrounds these dual goals for the Amazon by estimating the marginal effects of new agricultural land on the full income and assets of farm settlers over a 13-year period from 1996 to 2009. Using micro panel data from agrarian settlements where forest was being rapidly cleared, and controlling for factors that would otherwise confound the relationship, we estimate the effect of converting forest to agriculture on total household income to estimate the opportunity cost of conserving forest. Our measure of income reflects any re-allocation of resources by utility maximizing households and any productivity effects due to loss of forest ecosystem services. The estimated effect of new agricultural land on income is positive, but small relative to the income per hectare of previously cleared land. However, we show that income increases investment in physical assets, which raises households’ income generating capacity and future accumulation of assets. Thus, while there is only a small immediate income gain from clearing more forest, the long-term effects on wealth are still substantial. This demonstrates that given the right conditions, conversion of forest to agricultural land can be an impetus for asset accumulation by smallholders. It also highlights the importance of considering the indirect and long-term welfare benefits of new agricultural land when assessing the opportunity costs of forest conservation.     

Groundwater balance and conservation under different water pricing and agricultural policy scenarios: A case study of the Hamadan-Bahar plain

Government subsidies for agricultural activities in recent decades have encouraged farmers of Hamadan-Bahar plain to extend the number of wells and irrigated farms, with no consideration of groundwater resource conservation. As a result, the level of the groundwater table has decreased continuously in this area, threatening the life of groundwater aquifer. The objective of the study is to analyze the impacts of irrigation water pricing and agricultural policy scenarios on aquifer conservation by considering the dynamic relations between aquifer groundwater balance and the agriculture sector. For this purpose a combination of simulation and optimization techniques is considered in a dynamic framework. Firstly, dynamic treatments of groundwater and the main factors affecting the balance of studied aquifer are simulated. Then, optimization behaviour of agriculture sector related to farmers' decision-making processes is defined on the time horizon. Thereafter all of the equations are used simultaneously by a non-linear dynamic programming method, which maximize present value of gross margins of agriculture sector subject to groundwater constrains and other input limitations. The analysis of the results indicates that water pricing by itself can considerably reduce the agricultural demand for aquifer groundwater in the Hamadan-Bahar plain.     

WILLINGNESS TO PAY FOR AIR QUALITY: THE CASE OF OUTDOOR EXERCISE

This study uses a contingent valuation (CV) survey to establish a sample of outdoor exercisers' willingness to pay (WTP) for ambient air quality improvements in East Baton Rouge parish, Louisiana. Estimated annual median and mean WTP values are £95 and £191, respectively, per person per year for assurance that ozone levels would not become "unhealthful" on any day. The survey informed respondents that in the prior year the local community experienced 14 days on which ozone levels exceeded federal standards. The study makes the strong assumptions that respondents believed they were "buying" 14 more healthy days and that WTP per day "bought" is constant. Given these assumptions, one can scale this WTP response to represent annual medians and means of approximately £7 and £14 per person per day, respectively. An econometric procedure for generalizing the community's annual WTP to avoid the 14 unhealthful days yields estimates ranging from £3.21 and £5.36 per person per healthy day, or between £12.4 and £20.6 million per year. The unit day estimates are comparable to CV and household production finction estimates of WTP in the Los Angeles basin, suggesting their usefulness for benefits transfer .     

The Value of Household Water Service Quality in Lahore,Pakistan

Most existing literature focuses on the benefits of establishing basic drinking water access for unserved populations, the extensive water supply margin. In contrast, this article examines the intensive margin—the benefits of improving water service to under-served households, a growing population in developing country cities. We use contingent valuation to estimate willingness to pay (WTP) for improved piped water quality and reductions in supply interruptions among a sample of 193 households in Lahore, Pakistan. The distribution of WTP is described using parametric and non-parametric models. Results indicate that households in Lahore are willing to pay about 7.50 to7.50 to 9 per month for piped water supply that is clean and drinkable directly from the tap—comparable to the monthly cost of in-home water treatment, and about three to four times the average monthly water bill for sample households using piped water. Estimates of WTP for reducing supply interruptions are both smaller and more difficult to interpret, since a significant fraction of the estimated WTP distribution for supply improvements is negative. All of our WTP estimates are well below 4% of monthly household income, the World Bank’s benchmark upper bound for affordable water service.     

Use of Contingent Valuation to Elicit Willingness-to-Pay for the Benefits of Developmental Health Risk Reductions

We report the results of several contingent valuation (CV) surveys to elicit willingness-to-pay values from the general public for risk reductions associated with decreases in exposure to a chemical, PCBs, in the environment. We also develop Quality Adjusted Life Years (QALYs) from the survey using both standard gamble and time-tradeoff elicitation methods to explore the relationship between QALYs and willingness-to-pay (WTP), and to develop QALY weights for subtle developmental effects. The results of the CV surveys are designed for incorporation into a case study of an integrated risk model to monetize the benefits of predicted risk reductions. Respondents showed a nearly proportional, positive relationship between decreasing the risk of a 6-point reduction in IQ (a standard measure of “intelligence”) and WTP, but showed a negative relationship between risk reduction and WTP for reading comprehension as an outcome. The range of mortality risks that respondents would accept on behalf of their (hypothetical) 10-year-old child is 2 in 10,000 to 9 in 1,000 per IQ point, and WTP per IQ point is $466 ($380, $520). QALY weights elicited via time tradeoff (reduction in life expectancy) were significantly different from QALY weights elicited via a standard gamble (p = 0.001). Respondents who answered questions about ecological endpoints first were willing to pay a small additional amount when asked about human health effects, but those respondents who answered questions about human health endpoints first were not willing to pay any additional amount when subsequently asked about ecological effects. This paper has not been submitted elsewhere in identical or similar form, nor will it be during the first three months after its submission to the Publisher.     

Watershed externalities, shifting cropping patterns and groundwater depletion in Indian semi-arid villages: The effect of alternative water pricing policies

Frequent droughts and groundwater depletion are critical constraints to improving agricultural productivity in the semi-arid tropics. India has been promoting integrated watershed management in drought-prone areas to address these constraints. Watershed communities are being assisted to invest in groundwater re-charging facilities. While communities and the public bear such costs, individual farmers capture irrigation benefits. Groundwater is a free common property resource and land users hold de-facto use rights. This has accelerated private irrigation investments and depletion of aquifers resulting in iniquitous distribution of irrigation water. Power subsidies and negligible pumping costs aggravate the problem. These policy failures and low irrigation costs to farmers are displacing water-efficient crops in favor of water-intensive crops in water-scare areas. The paper reviews the village-level externalities that aggravate groundwater depletion and evaluates potential policy options to enhance local collective action in water management. Using 3SLS, an econometric crop-water productivity model is used to evaluate alternative water policy instruments. The results indicate that different types of water user charges can be introduced with modest consequences on profitability and farm incomes. If properly implemented and managed by the local communities, pro-poor policies could bring considerable sustainability benefits and also ensure enhanced equity in access to the resource.     

干旱指数保险支付意愿研究——基于湖北省孝感市的实证分析

本文以湖北省孝感市273个农户的调查数据为依据,通过Logistic模型对农户干旱指数保险支付意愿的影响因素进行了实证分析。研究表明：被调查农户农业干旱保险意愿不强,其中72.5%的农户没有支付意愿;有支付意愿的农户愿意支付的保险费也相当低,平均只有每亩12元。基于此,本文为该地区农业干旱指数保险的发展提供相关政策建议：加大对农村的人力资本投资;增加农民收入,提高支付能力;加强农业干旱指数保险的宣传教育工作;探讨合理的农业保险补贴方式和标准;加强天气指数保险研究力度,积极推进天气指数保险试点工作。     

The Economic Value of Air-Pollution-Related Health Risks in China: A Contingent Valuation Study

The economic value of preventing adverse health effects related to air pollution is estimated using contingent valuation in three diverse locations in China. Values are estimated for three health endpoints: cold, chronic bronchitis, and fatality. Alternative statistical models are tested to study their impact on estimated willingness to pay (WTP) and on the relationship between WTP and respondent characteristics. Using the official exchange rate, the sample-average median WTP to prevent an episode of cold ranges between US$3 and US$6, the WTP to prevent a statistical case of chronic bronchitis ranges between US$500 and US$1,000, and the value per statistical life ranges between US$4,000 and US$17,000. Estimated mean values are between two and thirteen times larger. Our estimates are between about 10 and 1,000 times smaller than estimates for the US and Taiwan using official exchange rates. Indoor air quality, measured for a subset of respondents, shows no consistent relationship with WTP.     

Willingness to Pay and Sensitivity to Time Framing: A Theoretical Analysis and an Application on Car Safety

Stated preference (SP) surveys attempt to obtain monetary values for non-market goods that reflect individuals’ “true” preferences. Numerous empirical studies suggest that monetary values from SP studies are sensitive to survey design and so may not reflect respondents’ true preferences. This study examines the effect of time framing on respondents’ willingness to pay (WTP) for car safety. We explore how WTP per unit risk reduction depends on the time period over which respondents pay and face reduced risk in a theoretical model and by using data from a Swedish contingent valuation survey. Our theoretical model predicts the effect to be nontrivial in many scenarios used in empirical applications. In our empirical analysis we examine the sensitivity of WTP to an annual and a monthly scenario. Our theoretical model predicts the effect from the time framing to be negligible, but the empirical estimates from the annual scenario are about 70 % higher than estimates from the monthly scenario.     

浙江省地下水资源战略储备体系研究

科学合理地开发利用地下水资源、实施地下水资源储备战略,是保障浙江经济可持续发展和未来水安全的一项重要措施。本文针对浙江省水资源储备的形式和地下水使用状况,分析了建立地下水资源战略储备的作用,说明了建立地下水资源储备所需的条件,并提出实施地下水资源战略储备建议。     

森林资源生态价值支付意愿的实证分析——以“京津唐—承”区域为例

本文针对我国河北省承德市森林资源,以"京津唐—承"区域为研究对象,通过建立多元线性回归模型,分析了影响居民对森林资源生态价值支付意愿的诸多因素,并根据平均支付意愿对承德市森林资源生态价值及相关方的受益大小进行了估算。结果表明,承德市森林资源生态价值为163.27亿元,其中森林资源所在地承德市受益17.92亿元,占10.98%,周边区域京津唐3市受益145.35亿元,占89.02%。在众多因素中,收入、居住地以及对森林资源重要性的认识程度是影响居民对森林资源生态价值支付意愿大小的主要因素。