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991.
In the first, the paper gave a retrospective analysis on the comprehensive assessment of circular economic development. According to the requirement of improving resource & environment efficiency, the paper designed an analytical framework for a comprehensive assessment of regional circular economic growth, which consists of the goal, object and technical line of the comprehensive assessment of regional circular economic development. Given that, the paper discussed the criterion for choosing the assessment index, the approaches of index's weighing determination, the means of data standardization, and the reference system of assessment index value and so on. According to the framework of regional circular economic development evaluation, the paper made a comprehensive evaluation of Jiangsu Province's circular economic development. The result shows that from temporal change, Jiangsu Province's circular economic development had different stages; from the spatial comparison, there is variance among different regions, which could be divided into different types according to the spatial variance and the relation between the development of circular economy and the aggregative index number. There was a remarkable correlation between circular economic development level and GDP or the 2nd industry GDP. Finally, the ?aper gives some suggestions on how to promote the development of drcular economy in Jiangsu Province.  相似文献   
992.
川中丘陵区土地资源的可持续利用——以乐至县为例   总被引:1,自引:0,他引:1  
川中丘区是四川省粮食经济作物的主产区,土壤肥沃、耕地少、土地利用复杂。以乐至县为例,探讨了该县土地资源的可持续利用。  相似文献   
993.
利用工厂化流水线,对生活垃圾进行人工分拣,使资源各尽其用,是解决我国目前垃圾围城、资源紧缺、环境污染的最佳途径,同时可以吸纳大量人员就业.  相似文献   
994.
995.
不同释钾菌对粉煤灰的生态效应   总被引:1,自引:0,他引:1  
粉煤灰治理难度大,但它含有植物生长必需的营养元素钾,将其就地资源化生物利用是一条较好的途径。释钾菌是一种能把矿物中的难溶性钾转化为有效钾的细菌,从土壤中筛选出2种释钾菌,经过在粉煤灰基质中的驯化培养,通过盆栽试验种植紫花苜蓿,比较不同菌株对粉煤灰的改良作用及其对植物生长的影响。结果表明,筛选出的菌株C6对粉煤灰中速效钾的释放效果明显,降低了基质pH,显著地促进了植物的生长,对粉煤灰生态修复具有重要意义。  相似文献   
996.
陈曦川  李琳 《灾害学》1998,13(2):33-36
为加强洪灾研究工作,做好灾前预评估、灾中跟踪评估、灾后详细评估工诈,应用地理信息系统(GIS)技术,建立起海河流域西三洼(东淀洼、文安茬、贾口控)洪灾遥感监测背景信息系统。  相似文献   
997.
Contrast with artificial environment, the multi-level self-organizational system of nature has great gain. Sustainable material environment should respect nature: non-rubbish and super-cycle quality of natural ecosystem offers the material source of human development, fractal structure of nature offers new field of space and information source to this high-density and information-based society, dissipative structure of nature links the new system of energy with whole ecosystem organically, and life-chain regulation is the base of sustainable life environment. Nature guarantees the physical healthy environ- ment by its all-dimension healthy factor, constructs the mental healthy environment by its quality of co-ordinate and chaos, so that guarantees the whole emergence of sustainable development on the 'super-science' level In the view of sustainable development, construction, green economy and human health are basic fields. With the concept of ecosystem regulation, we can relate these fields organically and fulfill the task of human health, welfare and sustainable development. Ecosystem regulation is the base of sustainable development's new paradigm.  相似文献   
998.
根据系统实测资料,利用根层土壤水的变化量,按水量平衡公式反算求得观测年、季及旱月的土壤蒸散量.以三年平均及旱年土壤吸入水量减去蒸散量的结果显示,两个观测试区0~100cm土层蒸散量大于吸入水量;若以月平均计,则每月蒸散量大于土壤吸入水量3.84~8.60mm,土壤水的吸入略小于消耗,一年内土壤水量接近平衡.  相似文献   
999.
探讨以猪粪为培养介质,驯化和加富培养获得硫细菌混合菌液,并研究其对猪粪中重金属的生物沥浸效果。结果表明:猪粪可以在18 d内完成驯化,经3轮富集培养的猪粪粪液可作为硫细菌接种菌液。采用此菌液对猪粪粪液接种并投加硫粉,经过9 d的生物沥浸,Cu、Zn和Cd的沥出率分别达到93.0%、90.1%和67.8%。  相似文献   
1000.
Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment.  相似文献   
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