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1.
甘肃省旅游中的环境问题及生态旅游资源的开发 总被引:1,自引:0,他引:1
王勋陵 《甘肃环境研究与监测》1997,10(4):46-48
探讨了旅游业中存在的环境问题,阐述了甘肃省开发生态旅游资源的前景,提出了生态旅游的具体实施方案。 相似文献
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Vegetation patterns and nature reserve construction in an extremely-arid desert in Anxi,NW China's Gansu Province 总被引:2,自引:0,他引:2
Anxi County is located in the northwestern part of the Hexi Corridor in gansu Province and has the sole national level nature reserve of extremely-arid desert in China.Phytosociological methods (Braun-Blanquet,1964) are used to classify plant community types in this area.Eleven are disting uished,including six of deserts,four of oases and one transitional type between deserts and oases.Direct gradient analysis (DCA) is employed to correlate the distribution of plant communities to physiogeographic conditions.This study makes clear that water is the most important ecological factor for the distribution of plant species and communities in this area.The effects of water have been demonstrated in different ways.A vegetation gradient from lower altitude to higher altitude in the southern part of the reserve is driven by a precipitation gradient.The effects of the depth of ground water table contribute to the differentiation of vegetation from desert to oasis in the flat area.In a finer scale,the washed gullies have obviously higher species richness and also higher vegetation cover than the surround gobi surfaces,possibly caused by the effects of floods.The vegetation patterns demonstrate that the area of Anxi County is a complete landscape unit.The range of the current nature reserve is not large enough for the purpose of conserving the unique biodiversity in this area. 相似文献
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The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau 总被引:3,自引:0,他引:3
Due to relatively strong human activities in the hilly area of Loess Plateau,the natural vegetation has been destroyed,and landscape pattern based on agricultural land matrix was land use mosaic composing of shrub land,grassland,woolland and orchard.This pattern has an important effect on soil moisture and soil nutrients.The Danangou catchment,a typical small catchment,was selected to study the effects of land use and its patterns on soil moisture and nutrients in this paper.The results are as follows:The comparisons of soil moisture among seven land uses for wet year and dry year were performed:(1)the average of soil moisture content for whole catchment was 12.11% in wet year,while it was 9.37% in dry year;(2)soil moisture among seven land uses was significantly different in dry year,but not in wet year;(3) form wet year to dry year,the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasing type;(4)the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope,while complicated distribution of soil moisture was observed in multiple land uses along slope.The relationships between soil nutrients and land uses and landscape positions were analysed:(1)five nutrient contents of soil organic matter(SOM),total N(TN),available N(AN),total P(TP) and available P(AP) in hilly area were lower than that in other areas.SOM content was less than 1%,TN content less than 0.07%,and TP fallow land and cropland,and higher level in soil fertility was found in crop-fruit intercropping land among croplands;(3)soil nutrient distribution and responses to landscape positions were variable depending on slope and the location of land use types. 相似文献
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康秀南 《安全.健康和环境》2002,2(6):29-30
西气东输管道工程是国家实施西部大开发战略的标志性工程之一,该工程西起新疆轮南,东至上海白鹤镇,全长4200km,管径1016mm,壁厚14.6mm~26.2mm,设计压力10MPa.工程横贯我国东西9个省市,途径我国几大主要水系、荒漠戈壁、黄土高原、太行山、江南水网,沿线人文和自然环境差异较大.全线穿越等级以上公路、铁路和大中型河流704次.工程战线广阔,施工周期长,技术性较强,工艺复杂,采用国际通用的施工标准,创国家级优质工程.如何组织好该工程的施工管理,是参与施工的每一个单位需要很好探讨的问题.本文根据胜利油建西气东输项目部参与西气东输管道工程全线现场踏线的实际勘察和投标过程的分析策划事例,重点阐明在西气东输管道工程施工中推行HSE管理的重要性. 相似文献
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《防灾科技学院学报》2007,9(2):F0002-F0002
2007年5月30日-6月5日.我院大学生社会实践团师生一行24人赴甘肃进行了为期一周的社会实践活动。
本次实践活动是为贯彻中国地震局党组关于精神文明建设的意见和加强大学生.青年教师思想政治工作.我院组织的以大学生艺术团为主体的一次重要尝试。本次活动得到了中国地震局党组和局直属机关党委的高度重视。中国地震局党组成员.副局长修济刚同志和中国地震局直属机关党委常务副书记刘连柱同志对本次活动作了重要指示。学院领导也对本次活动提出了明确要求。 相似文献
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