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761.
762.
K. A. Edwards 《Natural resources forum》1993,17(1):59-64
This paper for the most part constitutes the address which was made to the Consortium for International Development at their recent Presidential Symposium at Colorado State University on 30 July 1992. It raises some of the global issues in water resources development and management which are likely to confront the international community in the 1990s and beyond. The issues pose the challenge to institutions involved in the water resources field in both developed and developing countries. 相似文献
763.
Inconsistent findings have been reported in the few studies investigating the relationship between the perceived value of pay and incentive performance. One hundred and seventy-eight female incentive employees with a nine-week, non-judgmental performance measure responded to a developed valence of pay scale. This measure used items assessing the perceived ability of pay to address employee needs. Three factor-scales were found within these items. Support for the hypothesized positive relationship between pay valence and incentive performance was found, dependent on which of the three scales was used. These findings provide initial insight into the means by which pay, with its ability to address different needs, might provide differential employee motivation and performance levels. This study and future research issues are discussed. 相似文献
764.
C. B. Cluff K. J. DeCook W. G. Matlock 《Journal of the American Water Resources Association》1971,7(4):726-739
ABSTRACT .Many growing municipalities near irrigated agriculture are advocating a transfer of water now utilized for irrigation to municipal use. Alternatives are presented whereby this water can be transferred to municipal use in exchange for treated sewage effluent. The irrigation water would in effect be cycled through the municipal system prior to use on the farms. A case study of the Tucson region illustrates the relevant legal, economic and technical aspects. Effluent could be delivered to irrigators in Avra Valley at a cost less than that now paid for water pumped from declining water tables. In return the City of Tucson could import ground water now being used for irrigation through an existing pipeline which presently cannot be used because of a court injunction obtained by the irrigators. It appears that such an exchange agreement could be made without modification of existing statutory law. Similar exchange arrangements may prove to be feasible in other regions containing irrigated agriculture. Increased efficiency of water use can be achieved avoiding external effects which commonly arise in a direct transfer and are difficult to evaluate. High quality water is allocated to municipal use whereas nutrient-rich sewage effluent is transferred to irrigation. 相似文献
765.
766.
Geoelectrical investigations in Grundy County of northwestern Missouri, where the groundwater resources of the glacial deposits have already been examined through an extensive drilling program by the Missouri Geological Survey and Water Resources, indicate that water-bearing gravel deposits can be distinguished from glacial deposits containing appreciable amounts of clay and limited amounts of water. The Schlumberger method used for the geoelectric depth soundings in the vicinity of the Survey's drillholes demonstrates the exploratory usefulness of the method in that it can partly replace the more expensive procedure of drilling. The method also provides improved interpretation between drillholes. Results of the investigation show that, in the area, clay has a resistivity below 20in, that the fresh water-bearing gravel at the bottom of the buried glacial stream channels has a resisitivity of 40 to 50fim, and that the near surface glacial gravel deposits have a resistivity above lOOfim. Interpretation of the depth soundings and the conductivity of water obtained from a local well implies that its water is drawn from the saline water of the bedrock. A recommendation is made for the quality improvement of this particular well. 相似文献
767.
大空间火灾烟气流动的动态显示研究 总被引:4,自引:0,他引:4
讨论了火灾烟气流动过程的计算机动态模拟方法。利用Delphi可视化编程工具,建立了一个融区域模拟计算和计算机动态显示于一体的火灾发展的模拟软件,并以中国科技大学的大空间建筑火灾实验厅为对象,对典型火灾羽流及烟气层的发展过程进行了动态显示。 相似文献
768.
Regional Representativeness of Swedish Reference Lakes 总被引:1,自引:1,他引:0
Richard K. Johnson 《Environmental management》1999,23(1):115-124
/ Recent focus has been placed on ecoregion delineations for providing an appropriate framework for monitoring and assessment of region-specific attainable water/habitat quality. Using an ecoregion approach to stratify variance, this study was conducted to determine whether earlier (subjectively) selected Swedish reference lakes may be considered as regionally representative reference sites when compared with a randomly selected lake population. Predictive modeling by discriminant function analysis with lakes classified by ecoregion and lake surface area and six physicochemical variables showed that the greater majority of reference lakes may be considered as regionally representative. The highest proportion of lake "misclassifications" occurred in the boreonemoral ecoregion, a relatively diverse ecoregion of southern Sweden. This apparent bias may be in part be due to the criteria used in selecting regional reference lakes. In the earlier selection of reference lakes emphasis was placed on lakes not being adversely affected by land usage or pollutant discharges, consequently forest lakes were often overrepresented and sites in agricultural areas underrepresented in the selected reference sites. As a complement to predictive modeling, PCA ordination showed the placement of reference lakes within the random lake population and indicated where reference sites might be missing along potentially important ecological gradients. KEY WORDS: Regionalization; Ecoregion; Representativeness; Reference; Ordination; Modeling; Temperate lakes 相似文献
769.
Landslides, risk and decision-making in Kinnaur District: bridging the gap between science and public opinion 总被引:2,自引:0,他引:2
Pilgrim NK 《Disasters》1999,23(1):45-65
In November 1989 a major landslide destroyed the link road to the village of Sapni in Kinnaur District of Himachal Pradesh in the Indian Himalaya. Although aware of the risk of further landslide activity, the community has campaigned successfully for reconstruction of the road. Decisions of this kind take place at the local level, through village institutions and open debate, with good feedback between villages and district government authorities. In this way a balance is established between meeting more immediate needs (such as domestic water supply, irrigation, road access) and taking acceptable risks. Using the Sapni landslide as a case study, this paper explores the issue of 'acceptable risk', and looks at the existing strategy for risk and disaster reduction in the district. 相似文献
770.
Costs and benefits associated with matings and the effects of mating frequency on fitness commonly differ between the sexes. As a result, outcrossing simultaneous hermaphrodites may prefer to copulate in the more rewarding sex role, generating conflicts over sperm donation and sperm receipt between mates. Because recent sex role preference models remain controversial, we contrast here some of their assumptions and predictions in the sea slug Chelidonura sandrana. For this hermaphrodite with sperm storage and internal fertilisation, risk-averse models assume that fitness pay-offs are constantly higher in the female than in the male function in any single mating. Moreover, excluding mutual partner assessment, these models predict male mating behaviour to be independent of receiver traits. The competing gender ratio hypothesis assumes that relative fitness pay-offs, and thus the preferred mating roles, vary and may reverse between matings and predicts that ejaculation strategies co-vary with receiver quality. We found that field mating rates of C. sandrana substantially exceeded what is required to maintain female fertility and fecundity, indicating large variation in direct female benefits between matings. We further demonstrate that male copulation duration adaptively increased with partner body size (i.e. fecundity) but decreased with recent partner promiscuity. These findings are compatible with the gender ratio hypothesis but contradict risk-averse models. 相似文献