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241.
Lee H. MacDonald James A. Hoffman 《Journal of the American Water Resources Association》1995,31(1):79-95
ABSTRACT: Both catchment experiments and a review of hydrologic processes suggest a varying effect of forest harvest on the magnitude of peak flows according to the cause of those peak flows. In northwestern Montana and Northeastern Idaho, annual maximum flows can result from spring snowmelt, rain, mid-winter rain-on-snow, or rain-on-spring-snowmelt. Meteorologic and physical data were used to determine the cause of annual maximum flows in six basins which had the necessary data and were smaller than 150 mi2. Rain-on-spring-snowmelt was the most frequent cause of annual maximum flows in all six basins, although there was a strong gradient in the magnitude and cause of peak flows from southwest to northeast. Less frequent mid-winter rain-on-snow events caused the largest flows on record in four basins. Mid-winter rain-on-snow should be distinguished from rain-on-spring-snowmelt because of differences in seasonal timing, the relative contributions of rain vs. snowmelt, and the projected effects of forest harvest. The effects of mixed flood populations on the flood-frequency curve varied from basin to basin. Annual maximum daily flows could not be reliably predicted from rainfall and snowmelt data. 相似文献
242.
H. Riekerk 《Journal of the American Water Resources Association》1983,19(1):73-79
ABSTRACT: Three forest watersheds were isolated by roads in poorly drained flatwoods of Florida. After 12 months of baseline calibration the forest in one watershed was harvested and regenerated with minimum disturbance, in the second watershed with maximum disturbance from common practices, and in the third watershed left intact as a control. Water yields from the maximum treatments increased a significant 250 percent while that from the minimum treatments increased 117 percent as compared to the control. Weed vegetation remaining after the minimum treatment continued significant water use. The water yield increases lasted only for one year. Water quality was reduced by both treatments with the most effect immediately after the maximum disturbance. Absolute levels of suspended sediments, potassium, and calcium remained relatively low. The maximum treatment caused significant changes in net cation balances only for one year. The information shows relative little effect of silvicultural practices in flatwoods on water quality as compared to data from upland forests. Water yield increases may be manipulated by the degree of harvest and weed control practices. 相似文献
243.
Cor van der Weele 《Journal of Agricultural and Environmental Ethics》2006,19(3):313-324
Official Dutch food information apparently tries to avoid images but is implicitly shaped by the metaphor that food is fuel.
The image of food as fuel and its accompanying view of the body as a machine are not maximally helpful for integrating two
important human desires: health and pleasure. At the basis of the split between health and pleasure is the traditional mind–body
dichotomy, in which the body is an important source of evil and bodily pleasure is sinful and dangerous. In the search for
alternatives, new metaphors are proposed that integrate mind and body as well as pleasure and health. The relevance of metaphors
for ethics is at least twofold. (1) Moral thought and theory are at least partly shaped by metaphors. In the light of this
growing recognition, the analysis of morality needs innovation. (2) With regard to food, new metaphors, such as slow food,
or the image of enjoyment as an art, enable a new search for morally responsible forms of hedonism, based on more love and
respect for human as well as animal bodies. But new metaphors are specific and selective, just like old ones. I argue that
a search for the best overall metaphor would be misguided, but that more diverse forms of attention to bodily aspects of life,
including experiences related to food, will result in richer vocabularies of the body, the mind, and body–mind relations.
This holds a promise of moral progress. 相似文献
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论述了在新形势下国有林场“三工”安全管理存在的问题,提出了坚持以人为本、以理服人、以情感人、加强企业安全文化建设的“三工”安全管理新机制。 相似文献
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构建煤矿职业安全卫生管理体系 总被引:2,自引:0,他引:2
安全生产是煤矿企业的头等大事。根据煤矿企业的实际特点 ,分析了煤矿安全生产管理的现状、特点和煤矿建立职业安全卫生管理体系的注意事项。讨论了建立煤矿职业安全卫生管理体系的步骤和方法 相似文献
249.
强调了劳动安全卫生设计的重要性,就《废气治理环保项目劳动安全卫生设计专篇》的编写方法进行了说明。指出了环保项目中常见的危险危害因素,并提出相应的防范技术措施。 相似文献
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