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291.
292.
草海是滇池的一部分,大量污水排入使草海水体污染日益严重,水体已达重富营养化水平,生态平衡遭受严重破坏,水功能基本丧失。为了保护滇池,必须彻底根治草海,对草海的根治拟采取如下综合成套技术:①改造城市排水系统;②对重点工业废水中的有毒有害污染物进行治理;③城市面源治理;④草海底泥疏挖;⑤污染物现场清除技术;⑥大型水生植物恢复技术;⑦水资源的合理调整。制定了草海及滇池治理的三期规划,实施总投资约30亿人民币。 相似文献
293.
294.
高地应力条件下Q系统在某勘探洞围岩分类中的应用 总被引:1,自引:0,他引:1
西南地区某水电站勘探洞高地应力是一个突出问题,高地应力洞段岩体属于坚硬岩或较坚硬岩,主要破坏方式是岩爆。高地应力区非岩爆岩体中未见结构性流变和软岩塑性流动等变形破坏现象,岩体质量较好。通过对岩体质量分类Q系统在该勘探洞高地应力洞段的应用,发现Q系统对于高地应力区非岩爆段岩体没有给出相应的SRF值;岩爆的发育条件是多方面的,但Q系统对岩爆的发育条件考虑较单一,所以它在高地应力区岩爆段的分类结果不能准确地体现出岩爆的等级和围岩类别。基于这2个问题,本文对Q系统做了相应的修改,以适应该勘探洞围岩分类,从修改后Q系统的分类结果看,效果良好。 相似文献
295.
探讨了项目财务评价结果和项目敏感性分析技术的应用方法,为某公司唐山中厚板厂污水处理回用项目融资方案和运营方案的决策提供依据.介绍了唐山中厚板材有限公司废水回收利用工程项目概况;确定了该项目的基础数据,进行财务分析,这是进行后续敏感性分析的基础.对此项目进行敏感性分析,找出影响该项目收益的敏感性因素,为该项目执行时的风险管理提供一定依据. 相似文献
296.
以"处方式"为主要特征的《建筑设计防火规范》、《高层民用建筑设计防火规范》等技术规范构成了我国现行民用建筑防火技术体系,其分类标准和技术体系尚需细化,诸多防火设计与建筑功能设计的矛盾仍无法得到有效解决.由于专家论证、性能化防火设计等途径尚未完善,因此细化建筑分类标准,完善防火技术手段,加快规范体系更新,仍是促进民用建筑防火技术体系不断完善成熟的有效途径. 相似文献
297.
298.
Identification and mapping of submerged plants in a shallow lake using Quickbird satellite data 总被引:1,自引:0,他引:1
Turkey is a country rich in lakes and wetlands--monitoring of all these will require advances in technology such as remote sensing. In this study, the aquatic plants of the large and shallow Lake Mogan, located in Central Anatolia were identified and mapped using high spatial resolution Quickbird imagery. As Lake Mogan is an important bird area the assessment of submerged plant species is of great value for ecosystem conservation and management. Quickbird multispectral image acquired on August 6, 2005 was geometrically corrected and a water mask was used based on strong absorption of Near Infrared (NIR) wavelengths by calm, clear and deep water. The water mask was applied using band reflectance values for a specific pixel satisfying the conditions of band decreasing property (Green>Red>NIR) and NIR相似文献
299.
Mark E. Jensen Roland L. Redmond Jeff P. Dibenedetto Patrick S. Bourgeron Iris A. Goodman 《Environmental monitoring and assessment》2000,64(1):197-212
The Little Missouri National Grasslands (LMNG) of western North Dakota support the largest permitted cattle grazing use within all lands administered by the USDA, Forest Service, as well as critical habitat for many wildlife species. This fact, coupled with the need to revise current planning direction for range allotments of the LMNG, necessitated that a broad-level characterization of ecosystem integrity and resource conditions be conducted across all lands within the study area (approximately 800,000 hectares) in a rapid and cost-effective manner. The approach taken in this study was based on ecological classifications, which effectively utilized existing field plot data collected for a variety of previous inventory objectives, and their continuous spatial projection across the LMNG by maps of both existing and potential vegetation. These two map themes represent current and reference conditions (existing vs. potential vegetation); their intersection allowed us to assign various ecological status ratings (i.e., ecosystem integrity and resource condition) based on the degree of departure between current and reference conditions. In this paper, we present a brief review of methodologies used in the development of ecological classifications, and also illustrate their application to assessments of rangeland health through selected maps of ecological status ratings for the LMNG. 相似文献
300.
Altun L Baskent EZ Gunlu A Kadiogullari AI 《Environmental monitoring and assessment》2008,137(1-3):149-161
The productivity of forest sites has been indirectly determined with solo wood production objective in forest management.
Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest
management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method
and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed
and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements
were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study
area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications
were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes;
dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate
anamorphic site index (SI) equations and three site index classes; good (SI=I–II), medium (SI=III) and low (SI=IV–V) were
determined. Some important differences between the methods were realized. The forest sites determined with site index estimation
method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined
with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site
of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest
sites of open and degraded areas should be determined according to direct method. 相似文献