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981.
云阳森林公园游客规模灰色预测 总被引:1,自引:0,他引:1
本文用灰色系统理论中的GM(1,1)模型预测了云阳森林公园的游客规模,提供了一种有价值的旅游景点游客数量预测方法. 相似文献
982.
J.P.W. Rivers 《Disasters》1982,6(4):256-267
In general, little attention has been given to differential survival between the sexes in disasters. Consideration of physiological differences between males and females would suggest that, all things being equal, morbidity and mortality after disaster, particularly where food shortage is involved, should indicate an excess male mortality. Such statistics as exist in disasters, as in chronic underdevelopment, show that it is females and especially girl children who are at highest risk. The basis of this lies in sex discrimination which is implicit in most social systems. 相似文献
983.
984.
论述了西藏昌都地区“三江”流域6县的林业资源,并对其进行了深入分析,提出了以保护为主,综合开发利用和管理的设想。 相似文献
985.
武陵源,位于湖南省西北部张家界市与慈利县、桑植县交界处,方圆369km~2,由张家界、天子山、索溪峪、杨家界、茅岩河、九天洞、天门山等景区组成。1982年,张家界被命名为我国第一个国家森林公园。1992年,武陵源(主要包括张家界、天子山、索溪峪)被联合国教科文组织作为世界著名的旅游胜地列入世界自然遗产名录。 相似文献
986.
陆良彩色沙林从地质价值看具有特殊性,是流水侵蚀地貌的代表,也是复原古环境的特殊证据。危沙成林的特异地貌以及呈色原因的复杂化,为发展科普旅游提供了特殊的条件。通过专家学者的考证及全球对比分析,彩色沙林中国唯一、全球罕见的地质稀缺性初步得到证实。另一方面,彩色沙林多彩的沙美在自然、美在协调,有较高的旅游观赏价值。 相似文献
987.
988.
A.J. Scott 《Journal of environmental management》1998,54(4):291-303
This paper assesses the contribution that forums have made in progressing sustainable land use policies and decisions within rural Wales. The examples of Cardigan Bay Forum and Wales Rural Forum are used to show how sustainability has been addressed within their overall agendas. The contemporary debate about sustainable development has provoked a new organizational response with forums visible in many activities and initiatives. The traditional adversarial approach between groups has been replaced by a more sophisticated and complex assemblage of bodies that together create the forum ideal. Consensus, partnership and mutual understanding form the language of this new discourse. However, their presence raises certain key questions as to their role, purpose, representativeness and value in rural resource management debates. These questions have not been considered in the literature, and with the increasing proliferation of forums generally, there is a need to assess whether they are bringing about real and effective change. The two examples reveal clear evidence of forums as agents of change. However, there is considerable tension within both forums, within a climate of financial and membership vulnerability, between the need for involving all legitimate interests and the need to achieve meaningful outcomes for individual members. Such tension goes to the heart of who the two forums actually represent and their resulting actions. The way that these tensions have been reconciled lie at the heart of the forum phenomenon.1998 Academic Press 相似文献
989.
This study evaluates the theoretical impact of climate change on yields and water use of two crops with different responses
to increased CO2 and which represent contrasting agricultural systems in Spain. In all cases the simulated effects of a CO2-induced climate change depended on the counteracting effects between higher daily ET rates, shortening of crop growth duration
and changes in precipitation patterns as well as the simulated effects of CO2 on the water use efficiency of the crops. For summer irrigated crops such as maize, the yield reductions and the exacerbated
problems of irrigation water availability simulated with climate change may force the crop out of production in some regions.
For winter dryland crops such as wheat, productivity increased significantly in some regions, suggesting a northward shift
of area suitable for wheat production in future climates. The study considered strategies for improving the efficiency of
water use based on the optimization of crop management decisions in a CO2-driven warmer climate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
990.
A preliminary study on the characteristics of fogwater in the masson pine forest in Chongqing, China
The masson pine (Pinns massoniana Lamb.) forest of 2000 ha situated on Nanshan, the south bank of the Yangtze River near Chongqing, China. From 1982, some trees began to die. Since then, half of the trees have died and the whole forest is in danger. Prom November 1986 to January 1987, a study dealt with the characteristics of fogwater in that area was carried out, in order to explain the relationship between acid fog and masson pine decline. The results of our study showed that the acid fog might be responsible in part for the decline of the masson pine forest. 相似文献