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151.
Option value is estimated for the Washakie Wilderness, northwest Wyoming, USA, using the contingent valuation technique. Consumer
surplus, the traditional measure of economic value, is estimated separately and compared with option value. Several populations
are tested, including Washakie visitors, Yellowstone National Park visitors, and residents from four metropolitan test markets:
Salt Lake City, Utah; Portland, Oregon; Nashville, Tennessee; and Orlando, Florida, USA. The average annual preservation option
value (consumer surplus) expressed by on-site wilderness visitors is $46.17 ($80.13), by urban residents is $9.70 ($8.97),
and by rural residents is $8.43 ($7.80). Four selected attributes are determined to be important in motivating option demand
for the Washakie, including existence value, bequest value, the desire for an on-site visit, and interest in securing the
visiting privileges of others. The results suggest that option value is important in wilderness valuation and that off-site
users account for a large part of the economic value of wilderness. 相似文献
152.
本文讨论了区域水资源的评价问题.无论是地表水、地下水,还是土壤水都是来源于大气降水,降水资源才是区域总水资源;同时讨论了区域水资源的平衡原理.降水资源转化了截留水、地表水、土壤水和地下水4项水资源.该文对这2种不同的水体进行了深入讨论,着重论述了土壤水资源的概念及其特征.并对潜水蒸发和水资源的价值问题提出了看法. 相似文献
153.
Thomas A. Fontaine 《Journal of the American Water Resources Association》1991,27(3):509-520
ABSTRACT: The areal mean precipitation (AMP) over a catchment is normally calculated using point measurements at rainfall gages. Error in AMP estimates occurs when an insufficient number of gages are used to sample precipitation which is highly variable in space. AMP error is investigated using historic, severe rainfalls with a set of hypothetical catchments and raingage networks. The potential magnitude of error is estimated for typical gage network densities and arrangements. Possible sources of error are evaluated, and a method is proposed for predicting the magnitude of error using data that are commonly available for severe, historic rainfall. 相似文献
154.
She-Kong Chong Stephen M. Moore 《Journal of the American Water Resources Association》1983,19(2):277-282
ABSTRACT: Twenty-two gaging stations were selected for developing a regional flood frequency curve for small (area less than 2 square miles) watersheds in southern Illinois. Five probability functions were compared, and the extreme value type I function was selected to develop the regional flood curve. The curve was generated with the index flood method and also another empirical method that related the function parameters to the watershed area. Estimated peak discharges with various return periods were compared with the results obtained from multiple regression analysis. 相似文献
155.
本文通过对人道主义思想和可持续发展理念的剖析,阐述了可持续发展理念的内涵和实质对人道主义思想精神内核的质疑,指出现代工业文明价值指针的片面所在,提出随着经济发展和社会进步,人类应该重新审视自然与人的关系,践行“协调”与“和谐”的人地共生论;应该重新审视自然的宽泛价值,认识“非资源”的非经济价值,从而实现文明取向和价值评判上的转型与重铸,以使可持续发展真正得以良性持续。 相似文献
156.
157.
以地市州为基本经济单元,以1999年主要相对指标为依据,通过综合值测算法,将全省划分为四类经济发展水平不同的地区,对四类地区平均总量指标、相对指标进行了对比分析,并揭示了其空间分布特征,简要分析了各类地区经济发展的条件和方向;以1999年、1978年各地市州GDP为例,对比分析了四川省区域经济不平衡发展的动态性特征。 相似文献
158.
159.
160.
Gideon Fishelson 《Journal of the American Water Resources Association》1973,9(4):801-815
The study contains the methodology of finding the optimal time to start the operation of a desalting plant or any other non conventional source of water for agricultural use in Israel. The essence of the methodology is the moving equilibrium price and quantity of agricultural products. The market of agricultural products is represented by a single demand curve and a supply curve which is derived from the agricultural sector production function. Both the demand for and the supply of agricultural products functions are shifting over time. The marginal value product of water is the critical value that determines the optimal time of a desalting plant. The study is static in the sense that dynamic aspects per se are not dealt with-e.g. learning by doing of building and operating desalting plants. The empirical results although used for illustrative purposes can be used as reference points for other detailed and more ‘exact’ studies on water desalination. 相似文献