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161.
窑尾监测SO_2时,有时会出现其浓度低于仪器最低检出限的情况,应根据窖尾类型、煤中硫含量大小,有无脱硫工艺等情况,认真对比、计算分析,以保证监测数据真实可靠。 相似文献
162.
西部高寒干旱地区的生态可持续发展在整个西部的大发展中是相当重要的组成部分。本文以内蒙古乌兰察布盟为例,列举其主要生态问题,分析这些问题产生的原因,论述该地近年来在生态可持续发展建设方面的政策、措施,以及成效,从而得出相关的启示:应加强环境资源再生能力建设,进行制度创新,尊重科学规律,采用科学手段等。 相似文献
163.
This article establishes a set of indicators and standards for landscape ecological sensitivity analysis of site resources by using the theories and approaches of landscape ecology.It uses landscape diversity index(H),evenness(E),natural degree(N),contrast degree(C) to study spatial structure and landscape heterogeneity of site resources and thus provides a qualitative-quantitative evaluation method for land planning and management of small ,medium scale areas.The analysis of Yantian District,Shenzhen of China showed that Wutong Mountain belonged to high lanscape ecological sensitivity area,Sanzhoutian Reservoir and Shangping Reservoir were medium landscape sensitivity area and high ecological sensitivity area;Dameisha and Xiaomeisha belonged to medium sensitivity area caused by the decline of natural ecological areas.Shatoujiao,Yantian Pier belonged to low sensitivity area but urban landscape ecological development had reshaped and influenced their landscape ecological roles in a great extent.Suggestions on planning,protection goals an development intensity of each site or district were raised. 相似文献
164.
国外城市自然保护与生态重建及其对我国的启示 总被引:24,自引:0,他引:24
论文对当前国外的城市自然保护与生态重建活动作了介绍。城市自然保护包括野生生物生境保护、城市地区湿地及自然景观保护等内容。城市生态重建则主要有生态公园建设、废弃地生态重建、城市扩散廊道体系建设等方面。城市自然保护与生态重建具有以生态学为基础,多学科交叉;注重生态过程的恢复;多目标、多层次规划设计的特点。在此基础上,论文给出了4点对于我国城市生态建设的启示。 相似文献
165.
铬渣的无害化处理和综合利用 总被引:4,自引:0,他引:4
铬渣产量大、毒性剧烈 ,是严重污染生态环境和危害人类健康的危险废物。介绍了铬渣各种无害化处理方法的解毒机理、工艺过程和应用实践 ,阐述了对铬渣进行综合利用的途径 ,并就铬渣的防治前景提出了建议。 相似文献
166.
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168.
IntroductionPolyaluminiumchloride(PAC) ,akindofinorganicpolymerflocculant,iswidelyusedinwaterandwastewatertreatment.InordertoincreasethecoagulationeffectofPACandimprovethequalityofPACproduct,itisnecessarytoraisethedegreeofpolymerizationofPAC .Generally ,t… 相似文献
169.
Given the key role of biogenic volatile organic compounds(VOCs) to tropospheric chemistry and regional air quality, it is important to generate accurateVOCs emission inventories. However, only a less fraction of plant species, in temperate grassland of Inner Mongolia, has been characterized by quantitative measurements. A taxonomic methodology, which assigns VOCs measurements to unmeasured species, is an applicable and inexpensive alternation for extensive VOCs emission survey, although data are needed for additional plant families and genera to further validate the taxonomic approach in grassland vegetation. In this experiment, VOCs emission rates of 178 plant species were measured with a portable photoionization detector( PID). The results showed the most of genera and some families have consistent feature of their VOCs emission, especially for isoprene, and provide the basic premise of taxonomic methodology to develop VOCs emission inventories for temperate grassland. Then, the taxonomic methodology was introduced into assigning emission rate to other 96 species, which no measured emission rates available here. A systematical emission inventory of temperate grassland vegetation in Inner Mongolia was provided and further evidence that taxonomy relationship can serve as a useful guide for generalizing the emissions behavior of many, but not all, plant families and genera to grassland vegetation. 相似文献
170.
In this paper,the relationship among land productivity,population pressure and the fluctuation mechanism of ecotone is analyzed,taking coumties and banners of southeast Inner Mongolia plateau as an example,which is the most fragile part in the farming and husbandry interleaving belt of north China due to its severe desertification degree and low level of economic development.The Cv for the total output value of agriculture decreases from southeast to northwest,with the same rule as which the overloading population cumulated distributes,and both indicators have close relation with the high linear coefficient of 0.83.These reveal the fluctuation mechanism for ecotone:fluctuation of the level of economic development is a scientific and practical measure both to weakness degree and to instability of ecotone,because it is a synthesized response to the variation of climate as well as irrational land uses,which reinforce and magnify the fluctuation.In detail,the heavier the population overloading,the severer the grassland reclamation,the stronger the dependence of regional productivity on rainfall,the lower the level of economic development,the rougher the fluctuation of ecotone,but the weaker the PRED system. 相似文献