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961.
Wei Wang Jianguo Jiang Xuelong Wu Shunwen Liang 《Journal of Material Cycles and Waste Management》2000,2(2):65-69
In China, controlling environmental pollution resulting from solid waste (SW) and hazardous waste (HW) has become one of the
most pressing tasks in the field of environmental engineering. It is reported that the annual generation of industrial solid
waste (ISW) in China exceeded 0.6 billion tons in the 1990s, and is increasing every year. Although ISW management has been
strengthened in recent years, about 40% of SW is put in uncontrolled landfill without appropriate treatment. According to
statistics from the national Environmental Protection Agency, the cumulative ISW uncontrolled landfill in China had reached
6.6 billion tons by the end of 1995, occupying around 55 000 hectares of land. Although some major uncontrolled landfills
were constructed, nonetheless groundwater contamination resulted from the use of low-standard liners and poor management.
Furthermore, about 20 million tons of ISW was discharged into the environment illegally, and a third of this waste was discharged
directly into water bodies, making ISW one of the greatest pollution sources for surface water and ground water. Environmental
pollution accidents resulting from SW occur about 100 times a year in China, and environmental issues frequently arise because
of ISW pollution. The practices of SW management, treatment, and disposal started relatively late in China, and for a long
time the management of SW pollution has received little attention compared with water and air pollution management. China
faces problems such as the insufficiency of management laws and regulations, insufficient investment, inadequate treatment
and disposal technology, and a lack of qualified technicians. At present, most treatment and disposal technology cannot meet
the requests for solid waste pollution control. In order to protect, restore, and improve environmental quality in China and
to realize sustainable development, the safe management and disposal of solid and hazardous wastes is a pressing challenge.
In recent years, much attention has been paid to SW management in China, and investment to develop management and treatment
technologies has increased. In 1995, the Law for Solid Waste Pollution Protection was issued, and work on solid waste treatment
and disposal began to be legally managed. SW treatment and disposal facilities have been constructed, and now operate in some
large and medium-sized cities. In particular, rapid improvements have been seen in ISW recycling, collection, and disposal
of municipal solid waste and regional HW management. All the figures in this paper are from 1995, and represent the situation
in China in that year.
Received: April 18, 2000 / Accepted: May 15, 2000 相似文献
962.
963.
Soil Fertility Quality and Agricultural Sustainable Development in the Black Soil Region of Northeast China 总被引:2,自引:0,他引:2
The black soil in northeast China is considered one of the most fertile soils in China. Consequently, the black soil region has become one of the most important regions for cereal grain production in China. Agriculture has developed rapidly since the early part of the nineteenth century. To date, approximately 70 percent of total land in the area is cultivated. Even though the agricultural production in this region is increasing continuously, some soil fertility quality problems have become serious. This is hampering agricultural development and sustainability in the region. A brief history of population growth and agricultural development in the region is presented. Major soil quality problems, particularly soil degradation and soil erosion, are analyzed. Based on studies, suggestions for improving soil quality and for promoting sustainable agricultural development in the region are presented. These suggestions include improving agricultural landscape patterns, developing conservation cultivation, promoting combinations of crop production with combinations of forestry and animal husbandry, and implementing integrated management for soil and water conservation. 相似文献
964.
对某厂办公楼裂缝产生的原因进行了分析 ,并对其沉降情况和墙体裂缝发展情况进行了监测 ,指出了某办公楼现状及其隐患发展的趋势 相似文献
965.
根瘤菌、丛枝菌根(AM)真菌与宿主植物共生的分子机理 总被引:2,自引:0,他引:2
丛枝菌根(AM)真菌和根瘤菌是两类重要的共牛微生物,分别能够与宿主植物形成丛枝菌根和根瘤,其中,对二者共有的宿主植物--豆科植物而言,则能够形成AM真菌-豆科植物-根瘤菌三重共生体.两类微生物与宿主植物共生关系建立的关键是二者之间的相互识别以及随后的侵染,其相互识别过程就是它们相互交换信号分子、相互作用的过程,而这两类微生物与宿主植物的识别过程具有许多相似之处.本文就根瘤菌、AM真菌与宿主植物在分子水平上的共生机理进行了综述,在对宿主植物分泌信号分子识别的基础上,提出植物根系对两类微生物侵染的感应机制,分析了共生体形成过程中相关基因的转录与表达,进而阐明了共生体的形成过程,并对本领域的未来发展提出了建议. 相似文献
966.
Shunwen Liang Jianguo Jiang Yan Zhang Xin Xu 《Frontiers of Environmental Science & Engineering》2008,2(3):358-363
The leaching characteristics of heavy metals in products of cement stabilization of fly ash from a municipal solid waste incinerator were investigated in this paper. The stabilization of heavy metals such as Cd, Pb, Cu, and Zn in fly ash from such incinerators was examined through the national standard method in China based on the following factors: additive quantity of cement and Na2S, curing time, and pH of leaching liquor. The results showed that as more additives were used, less heavy metals were leached except for Pb, which is sensitive to pH of the leachate, and the worse effect was observed for Cd. The mass ratio of cement to fly ash = 10% is the most appropriate parameter according to the national standard method. When the hydration of cement was basically finished, stabilization of heavy metals did not vary after curing for 1 d. The mixtures of cement and fly ash had excellent adaptability to environmental pH. The pH of leachate was maintained at 7 when pH of leaching liquor varied from 3 to 11. 相似文献
967.
流域生态补偿机制研究 总被引:17,自引:0,他引:17
由于流域生态服务的公共物品属性,政府需要建立流域生态补偿机制以提供足够的流域生态报务。本研究提出流域生态补偿机制的主要模式是公共支付体系,财政转移支付体系,自发组织的私人协议和自由贸易体系。模式的决定要素是流域尺度和产投明晰程度,其组成要素是补偿标准,实际补偿量,组织实施和竞争机制的使用. 相似文献
968.
催化铁内电解-生化法处理印染废水 总被引:36,自引:1,他引:35
纺织印染废水水质变化大、色度高,直接生物处理难度大.采用催化铁内电解法对浙江某地区的印染废水进行预处理,有效地去除了对生物有抑制的有机物,为后续的生化处理创造了有利条件,CODCr去除率达到85%;过去难以解决的色度问题也得到了有效的解决,可去除废水色度90%以上.另外,简要探讨了金属粒径,pH,温度等因素对去除有机物的影响.近40 d的连续流试验证明,内电解-生化工艺具有处理效果好、出水水质稳定、工艺设备简单、操作管理方便、能耗低等特点,是处理印染废水的有效方法之一. 相似文献
969.
970.
Shaobo Liang Armando G. McDonald Erik R. Coats 《Waste management (New York, N.Y.)》2014,34(11):2022-2027
Potato peel waste (PPW) as zero value byproduct generated from food processing plant contains a large quantity of starch, non-starch polysaccharide, lignin, protein, and lipid. PPW as one promising carbon source can be managed and utilized to value added bioproducts through a simple fermentation process using undefined mixed cultures inoculated from wastewater treatment plant sludge. A series of non-pH controlled batch fermentations under different conditions such as pretreatment process, enzymatic hydrolysis, temperature, and solids loading were studied. Lactic acid (LA) was the major product, followed by acetic acid (AA) and ethanol under fermentation conditions without the presence of added hydrolytic enzymes. The maximum yields of LA, AA, and ethanol were respectively, 0.22 g g?1, 0.06 g g?1, and 0.05 g g?1. The highest LA concentration of 14.7 g L?1 was obtained from a bioreactor with initial solids loading of 60 g L?1 at 35 °C. 相似文献