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521.
Asit K. Biswas Robert W. Dune 《Journal of the American Water Resources Association》1971,7(6):1137-1143
Decisions to develop water resources systems so far have been primarily taken on the basis of engineering and economic feasibilities. Very rarely, if ever, sociological feasibility has been considered, except in a very broad sense. Planning is for the people, and it should improve the quality of life. Hence, it is argued that water resources decisions ought to be primarily social ones, and that the success or failure of any resource development should not only be judged by its techno-economic excellence but also by its impact on people. Water resources planning process is discussed, and the difficulties associated with the evaluation of sociological feasibility of projects are enumerated. The social consequences of water development projects are traced through planning, construction, operation and management impacts. Finally, it is suggested that the foremost factor in the success of any water management program is the public understanding and acceptance of that program. 相似文献
522.
Richard A. Stephenson 《Journal of the American Water Resources Association》1971,7(6):1172-1179
Stream tributaries in the Des Moines River basin have been classified according to the glacial terrain through which they flow. Three stream types were categorized as follows: (1) streams that flow entirely on Wisconsin drift, (2) streams that flow entirely on Kansan drift, and (3) streams that have their headwaters located on new drift but have their lower reaches flowing on older drift. Selected channel and valley characteristics were measured and used to verify the stream type classification. Five variables were chosen for use in a multiple linear discriminatory analysis, which is a statistical technique developed for the purpose of classifying observations into one of several categories which have been predetermined. The streams in each group were verified with the exception of three anomalies based on the probability associated with the largest linear discriminant function. The rationale for the three anomalous streams is not easily determined. But, they are considered to be associated with pre-glacial drainage or at least pre-Wisconsin age drainage. Otherwise, the analysis shows that the major channels and valleys in the Des Moines River basin tend to reflect the glaciated upland surface. 相似文献
523.
524.
Bruce P. Van Haveren Eugene E. Farmer 《Journal of the American Water Resources Association》1971,7(6):1250-1252
Evaporation was measured from a circular evaporation pan, 18 inches in diameter and 8 inches deep. The pan was insulated on the sides and bottom using 2 inches of freon-blown polyurethane foam. A U.S. Weather Bureau Class A evaporation pan was used to obtain reference evaporation measurements. Water evaporation from the Class A pan and the insulated pan were highly correlated. Using a water-methanol mixture, the insulated pan may be operated at temperatures below 32 F; the equivalent liquid water evaporation may be determined using a regression equation. 相似文献
525.
James A. Seagraves K. William Easter 《Journal of the American Water Resources Association》1983,19(4):663-672
ABSTRACT Alternative combinations of water pricing and regulations are possible in allocating irrigation water. The best combination will depend on the value of water, ability to control deliveries, desire to subsidize agriculture, ownership traditions, crops grown, return flows, drainage problems, staff training, ability to collect fees, the number of farmers involved, etc. Marginal cost pricing is just one possible alternative and it is more a way of thinking about prices rather than a set system. The possibilities for achieving an equitable and efficient distribution of water are improved if some form of marginal cost pricing is included in the system of water charges. 相似文献
526.
Abdul Rahim Hj. Nik Richard Lee J. D. Helvey 《Journal of the American Water Resources Association》1983,19(1):47-50
ABSTRACT: This study tests the hypothesis that climatic data can be used to develop a watershed model so that stream flow changes following forest harvest can be determined. Measured independent variables were precipitation, daily maximum and minimum temperature, and concurrent relative humidity. Computed variables were humidity deficit, saturated vapor pressure, and ambient vapor pressure. These climatic variables were combined to compute a monthly evaporation index. Finally, the evaporation index and monthly precipitation were regressed with measured monthly stream flow and the monthly estimates of stream flow were combined for the hydrologic year. A regression of predicted versus measured annual stream flow had a standard error of 1.5 inches (within 6.1 percent of the measured value). When 10, 15, and 20 years of data were used to develop the regression equations, predicted minus measured stream flow for the last 7 years of record (1972–1978) were within 16.8, 11.5, and 9.7 percent of the measured mean, respectively. Although single watershed calibration can be used in special conditions, the paired watershed approach is expected to remain the preferred method for determining the effects of forest management on the water resource. 相似文献
527.
528.
Wastewater treatment sludge contains valuable nutrients, yet represents a residue problem due to the amount of heavy metals,
which is one of the factors preventing the use of sludge as fertilizer. In Sweden, the government has a declared aim of closing
the ecocycles of nutrients to arable land, while at the same time the existing limit values are among the lowest in the world.
This paper focuses on the opportunities for Swedish wastewater utilities (WWUs) to manage and reduce sources of heavy metals
in order to get sludge approved and recycled.
A case study focusing on sources of the heavy metals Cd, Cu, Hg, Ni, Pb, and Zn and the WWUs ability to influence the source
by means of existing regulations was traced and categorized. A substantial fraction of the heavy metals were shown to be caused
by diffuse emissions, such as the use of goods and products in society. For most sources discussed in the paper, a WWU can
only manage the sources to a limited extent, if at all.
This study shows that the WWUs cannot manage both recycling of nutrients and a decrease in heavy metals ending up in sludge.
Diffuse emissions of heavy metals must be examined in context, not as a separate phenomenon or an issue for a single actor.
The existing environmental legislation does not handle diffuse sources, yet long-term strategies for reducing the emissions
to wastewater treatment must involve the reduction of diffuse emissions. 相似文献
529.
Gwebu TD 《Environmental management》2003,31(3):0348-0354
Based on government and other relevant documentation, this paper explores the conceptual linkage between population, development,
and waste management in Botswana and the implications of this relationship for global climate change. Population is increasing,
albeit at a decreasing rate. Spatially, the population is becoming more and more concentrated as the rates and level of urbanization
increase. Economic growth has remained consistently high. The combined effect of population dynamics and economic development
are having a noticeable imprint on the environment in the form of increased waste generation. Poor waste management poses
a real threat to environmental sustainability in general and climate change in particular because of inadequate technology,
weak institutional mechanisms to enforce regulations, and low levels of sensitization among the public to deal with the problem.
Mitigation measures are suggested to minimize the negative effects of waste management on climate change. 相似文献
530.
Local people's attitudes towards conservation and wildlife tourism around Sariska Tiger Reserve, India 总被引:2,自引:0,他引:2
Udaya Sekhar N 《Journal of environmental management》2003,69(4):339-347
Conservationists in the recent years view local peoples' support for protected areas management as an important element of biodiversity conservation. This is often linked to the direct benefits, which local communities get from the protected areas. These benefits could be in the form of biomass resources, park funds diverted to local villages by state agencies and revenue from wildlife tourism. There are a very few studies which have attempted to study the direct relationship between benefits from wildlife tourism and local support for conservation. In India, wildlife tourism is restricted, and mostly controlled by state and private agencies. Wildlife conservation policy does not view tourism in protected areas as a source of revenue for the local communities. The present study examines the local people's attitudes towards wildlife tourism and the impact of benefits from tourism on the local support for Sariska Tiger Reserve (STR), India. STR is a flagship for tourism where protected areas are increasingly being visited and where local support for wildlife tourism has not been studied adequately. Results indicate that two-thirds of the respondents were positive towards tourism and support for conservation. The respondents were aware that more tourism benefits are possible from a well-conserved protected area. There appears to be correlation between benefits obtained by local people from wildlife tourism and other sources, and support for protected area existence, suggesting that benefits impact people's attitudes towards conservation. Some of the main problems are the unequal distribution of tourism benefits, lack of locals' involvement in tourism and development. There is a need to clearly address these issues, so that protected areas may get the support of local people, which may lead to sustainable development. 相似文献