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991.
以保障国家粮食安全、农产品质量安全与农业生态安全为目标,有效提高土地质量地球化学评价成果实用性,采用土地使用现状图斑作为评价单元,选择网格化土壤样品采集,对土壤样品中的N、P、K2O、Cr、Se、Ph等16种元素的指标进行了分析,并使用隶属度函数创建土地质量地球化学评估模型的方法,根据相应的土地质量地球化学评价规范实现了某地区土地质量的化学评价。结果表示,该方法具有较强的实用性,可作为土地科学管理及绿色农业发展推广的基础评估方法。  相似文献   
992.
目前,环境空气质量是最重要的民生问题之一,而济宁又是全国著名的煤化工产业基地,支柱产业均是以煤炭为原料,因此,环境空气质量更是大问题。通过深入的走访调查,济宁市的大气污染颗粒物主要是土壤风沙尘、煤尘、建筑尘、机动车尾气油烟飞灰、燃煤飞灰五种。本文采用CMB模型解析了这五种大气污染颗粒物的贡献值和分担率,其中,煤尘和燃煤飞灰是影响济宁市环境空气质量的主要原因,为此,提出济宁市的产业结构急需调整,煤化工产业需要向高附加值、低污染的精细化工产品和清洁能源产品的方向发展。  相似文献   
993.
经济的飞速发展和科学技术的不断进步,为医疗卫生事业日趋繁荣提供了有力的支持,进一步保证了人们的生命和健康。但与此同时,产生的医疗废弃物也逐渐增多,危害越来越严重,它不同于一般的废弃物,具有极强的传染性、生物毒性和腐蚀性,不仅会对环境造成污染,处理起来也是相当麻烦,成本也较高,加大了医院的经济支出,不利于经济循环利用。在此背景下,对医院废弃物的管理就成为医院管理部门的重点关注对象。因此先对医院废弃物管理方法进行简要阐述,然后建立相关模型,以此分析医院废弃物管理对环境污染与经济循环利用产生的影响。  相似文献   
994.
Shelter, housing and recovery: a comparison of u.s. Disasters   总被引:3,自引:0,他引:3  
Bolin R  Stanford L 《Disasters》1991,15(1):24-34
In this paper we examine the issues associated with the temporary sheltering and housing of victims after natural disasters in the United States. Specific topics addressed include differential access to shelter and housing aid according to social class, ethnicity and related demographic factors; the relationship between post-disaster shelter and housing and long-term recovery; the role of social support networks in the sheltering of victims; and the implications of the research for the provision of shelter and housing aid after disasters.  相似文献   
995.
Monitoring of airborne dust in Delhi during May to July 1985 revealed residues of DDT varying from 1.3 to 7.14 ng mg(-1) (4.06-22.31 ng m(-2) day(-1)) with an average of 3.32 ng mg(-1) (10.38 ng m(-2) day(-1)), and HCH which ranged from 0.46 to 2.35 ng mg(-1) (1.44-7.34 ng m(-2) day(-1)) with a mean of 1.16 ng mg(-1) (3.63 ng m(-2) day(-1)). The concentration of total DDT was almost 3 times greater than that of HCH.  相似文献   
996.
The relative tissue accumulation of Pb, Cd and Zn were compared in two populations each of two species of slugs (Arion subfuscus and Deroceras reticulatum). One population was resident at a contaminated Pb/Zn mine site, and the other population was from an uncontaminated site and was transferred for 20 days to microcosms established at the mine site. It was found that when the experiment was conducted during late spring (May), but not in late winter (February), that the Pb and Zn concentrations in the tissues of the 'transplants', were significantly higher than in the tissues of 'residents'; the Cd concentrations in the transplants, although significantly higher in the May sample than in February, did not exceed those of their 'resident' counterparts. It was postulated that: (a) Pb and Zn tolerance in slugs is phenotypically expressed by a reduction in metal accumulation; (b) Cd tolerance, if present, may be characterized by enhanced storage capacity; and (c) the presence of local metal-tolerant ecotypes is a biotic variable that may confound the relationship between dry tissue and environmental metal concentrations that forms a basis of pollution biomonitoring.  相似文献   
997.
Spring wheat (Triticum aestivum L., cv. Drabant) was exposed to different concentrations of ozone in open-top chambers for two growing seasons, 1987 and 1988, at a site located in south-west Sweden. The chambers were placed in a field of commercially grown spring wheat. The treatments were charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus extra ozone (NF(+)). In 1988, one additional ozone concentration (NF(++)) was used. Grain yield was affected by the ozone concentration of the air. Air filtration resulted in an increase in grain yield of about 7% in both years, compared to NF. The addition of ozone (NF(+), NF(++)) reduced grain yield and increased the content of crude protein of the grain in both years. Filtration of the air had no significant effect on the content of crude protein, compared to NF. The results showed a strong positive chamber effect on grain yield in the cold and wet summer of 1987. In 1988, there was no net chamber effect on grain yield. The relative differences between the CF, NF and NF(+) treatments with respect to grain yield were of the same magnitude in the two years, despite the very different weather conditions.  相似文献   
998.
The translocation of some heavy metals, such as Hg, Cd, Cu, Co, Ni and Zn, as affected by organic pollutants, i.e. methanol, ethanol, propanol, formaldehyde, acetaldehyde, benzaldehyde, acetone, ethyl methyl ketone and cyclo-hexanone, was studied in an Indian red soil using soil thin layer chromatography. It was observed that an increase in the concentration of organic compounds in developer enhances the heavy metal mobility, except in the case of Cu and Hg which show a decreasing trend. The results are discussed in relation to the physico-chemical characteristics of the soil and adsorption/desorption phenomena.  相似文献   
999.
Field-grown black cherry (Prunus serotina Ehrh.) seedlings were treated with the antioxidant ethylenediurea (EDU) to evaluate height, diameter, and above-ground dry-weight biomass growth response to ambient ozone over four years. Nine blocks with 44 trees/block were used in a randomized complete block design with three foliar spray treatments: (1) 1000 ppm EDU mixed with a surfactant and water; (2) surfactant mixed with water; and (3) water only. In each growing season treatments were applied seven times at approximately 10-day intervals. Repeated measures analysis of variance indicated significant (P< or =0.05) treatment and year effects for log-transformed height and diameter growth over the four-year period. After four years, EDU-treated trees were approximately 17% taller and stem diameters were 21% greater than non-EDU-treated trees. Total above-ground dry-weight biomass at the end of four years was 47% greater for EDU-treated trees compared to non-EDU-treated trees.  相似文献   
1000.
The research, focused on the specific interactions among seven plant secondary compounds and aphids, was carried out and the preliminary results showed: (1) "T-typed tube method" was regarded as the best method compared with others designed to observe the interactions. (2) Cabbage aphid was able to be attracted by laurolene while it was not susceptible to α-pinene, β-pinene and diamylene. (3) Gossypol, a major secondary substance in cotton, was able to be implicated as feeding attractant to cotton aphid. (4) Rutin might be implicated repellent to cotton aphid.  相似文献   
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