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101.
Stanley O. Blois 《Water, air, and soil pollution》1977,7(2):147-164
Patterns of energy use in the U.S. by industry, commerce, residential and agriculture with comparisons of Northern and Central California energy use in the same sectors are presented. End-use applications are also covered. 相似文献
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Measurements of downslope rock-creep, of the slow rate of plant establishment on alpine and subalpine road-cuts, and of the reduction in plant cover and plant production in two alpine plant communities, illustrate the degree of disturbance that can occur. The development of large trails or roads should not be permitted in areas of such active downslope rock movement, because of the natural rate of mass-wasting. If more people are to visit and enjoy the alpine communities, asphalt paths to confine their walking are desirable, for trampling experiments showed that plant cover and plant production were rapidly reduced in even one season of light use. Recovery during the following year was, however, quite rapid—especially in the snow-bank community. Different alpine and subalpine habitats have different sensitivities to disturbance, and any plans for increased human use must incorporate this kind of information. 相似文献
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A conservation experiment is described in which the losses in ensiling heavily-wilted herbage, of approximately 50% dry matter, in lined trench silos, with and without a polyethylene film seal, are compared. The composition and digestibility of the silages produced in the sealed silos were comparable with those of the original herbage. The content of organic acids in the sealed silos was low, suggesting that fermentation was suppressed by the partially gas-tight seal. In the unsealed silos there was considerable spoilage, 70% of the material being inedible. In the 2 sealed silos losses of dry matter were 8·2 and 5·2% and losses of SE 11·5 and 7·8%, respectively. The losses recorded are compared with those usually encountered in lined trench silos. 相似文献
107.
WRIGHT LD CRESSON EL SKEGGS HR PECK RL WOLF DE WOOD TR VALIANT J FOLKERS K 《Science (New York, N.Y.)》1951,114(2972):635-636
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