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791.
以往开发区区域环评编制对象主要是新建开发区,较少涉及工业用地开发强度几近饱和的老开发区。本文以江苏常州钟楼经济开发区中新闸工业园区的区域环评为例,围绕“优化、调整、再优化”的思路,阐述了此类开发区环评编制的评价要点及方法,以及开发区环评编制过程中如何与规划调整的反馈互动的机制,系统地提出了老工业区环境评价的技术体系,为此类经济开发区的合理规划提供了借鉴与参考。  相似文献   
792.
以资源、能源为依托的工业结构和粗放的增长方式是内蒙古工业的主要特点,也是实现节能减排目标的瓶颈。通过淘汰落后生产能力、加快接续产业发展、推动资源型产业发展高端和集成产品、促进节能减排技术的研发和应用、发展循环经济以及建立配套的政策、法规体系,力促内蒙古工业实现节能减排目标,走出一条资源节约与环境友好的新型发展道路。  相似文献   
793.
汞是环境中毒性最强的重金属之一,由于具有持久性、长距离迁移性和生物累积性被列为全球性污染物。土壤是汞重要的源和汇,在汞的生物地球化学循环中发挥关键作用,其理化性质可以显著影响汞的吸附分配行为。本文基于采自全国各地的131份农业土壤样品考察了汞(Hg2+)在土壤中的吸附分配行为,测定了Hg2+的固液分配系数(Kd),并探讨其与p H、有机质(OM)、粒度组成、溶解性有机质(DOM)和总硫等土壤理化性质的关系。利用逐步多元线性回归的方法分析发现旱地土壤对汞Kd的主要影响因素是DOM和土壤粒度,而水田的主要影响因素是总硫。通过淹水实验,进一步探究了土壤氧化还原对Hg2+分配的影响。研究发现,旱地土壤中,大部分土壤在淹水30 d后Kd呈明显增大趋势,继续淹水至60 d的Kd表现为稳定或下降的趋势;大部分水田土壤在淹水条件下Kd未表现出增大的趋势,且随淹水时间呈稳定或下降的趋势。  相似文献   
794.
Ascomycota was the predominant phylum in sanitary landfill fungal communities. • Saprophytic fungi may be of special importance in landfill ecology. • Both richness and diversity of fungal community were lower in leachate than refuse. • Physical habitat partly contributed to the geographic variance of fungal community. • NO3 was considered the most significant abiotic factor shaping fungal community. Land filling is the main method to dispose municipal solid waste in China. During the decomposition of organic waste in landfills, fungi play an important role in organic carbon degradation and nitrogen cycling. However, fungal composition and potential functions in landfill have not yet been characterized. In this study, refuse and leachate samples with different areas and depths were taken from a large sanitary landfill in Beijing to identify fungal communities in landfills. In high-throughput sequencing of ITS region, 474 operational taxonomic units (OTUs) were obtained from landfill samples with a cutoff level of 3% and a sequencing depth of 19962. The results indicates that Ascomycota, with the average relative abundance of 84.9%, was the predominant phylum in landfill fungal communities. At the genus level, Family Hypocreaceae unclassified (15.7%), Fusarium (9.9%) and Aspergillus (8.3%) were the most abundant fungi found in the landfill and most of them are of saprotrophic lifestyle, which plays a big role in nutrient cycling in ecosystem. Fungi existed both in landfilled refuse and leachate while both the richness and evenness of fungal communities were higher in the former. In addition, fungal communities in landfilled refuse presented geographic variances, which could be partly attributed to physical habitat properties (pH, dissolved organic carbon, volatile solid, NH4+, NO2 and NO3), while NO3 was considered the most significant factor (p<0.05) in shaping fungal community.  相似文献   
795.
络合萃取法与生物法处理含酚废水技术经济比较   总被引:2,自引:0,他引:2  
从技术经济角度对络合萃取法与生物法处理含酚废水进行了比较。建立了投资及净现值与处理量和浓度的关系式。结果表明:当浓度小于265mg/L时,络合萃取法与生物法随处理量的不同在投资上存在差别;当浓度大于265mg/L时,无论处理量为多少,络合萃取法的投资始终小于生物法的投资。对于处理量较大、浓度较高的废水,采用络合萃取法能获得较大的净现值(NPV);当回收酚时,盈亏平衡点的浓度为1000mg/L,高于此浓度,络合萃取法处理为盈利项目。  相似文献   
796.
乡镇工业小区能源综合利用与污染控制   总被引:2,自引:0,他引:2  
根据工业小区内企业的用能强度与生活布局的相互关系,首次对各类乡镇工业小区进行用能类型划分,将乡镇工业小区作为一个系统,工业小区内的用能企业和排污企业作为子系统,通过对不同用能类型的工业小区内重点耗能企业用能效率和重点污染企业综合治理的评价,找出适合乡镇企业特点,并在经济技术上可行的能源综合利用与污染集中控制的措施,提出以下几点政策建议:小区的基础设施建设和污染治理设施进行统筹考虑;能源环境综合治理应纳入小区总体规划之中;根据国家有关节能法规,制定不同类型工业小区能源综合利用效率标准和相应的产品单耗标准,推广清洁生产和污染物资源化处理技术  相似文献   
797.
Holographic quantitative structure-activity relationship(HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encoded the frequency of occurrence of various molecular fragment types, and the subsequent partial least squares(PLS) regression analysis. In this paper, the acute toxicity data to the guppy( poecilia reticulata) for a series of 56 substituted benzenes, phenols, aromatic amines and nitro-aromatics were subjected and this resulted in a model with a high predictive ability. The influence of fragment size and fragment distinction parameters on the quality of HQSAR model was investigated. The robustness and predictive ability of the model were also validated by leave-one-out (LOO) cross-validation procedure and external testing data set.  相似文献   
798.
湖泊水环境是一个受多种不确定性因素限制的复杂系统。以内蒙古乌梁素海为研究对象,应用水质超标灰色-随机风险率的计算方法和系统可靠性分析理论建立了单项参数评价模型和综合参数评价模型,分析湖泊入口断面水质存在的潜在风险性。结果表明:乌梁素海镉的Ⅴ类达标率仅为7.69%~23.89%,镉污染已经十分严重,硫化物和氰化物的Ⅲ类和Ⅴ类达标率都达到100%,所以几乎不受这两项指标的污染。该方法能较好地反映乌梁素海入口断面不同水质参数的污染强度和污染历时的变异过程,为湖泊水环境风险的决策和管理工作提供了参考依据。  相似文献   
799.
利用统计学方法提出了如何在应急监测中判断样本有无放射性,并结合实际监测做出了具体应用。  相似文献   
800.
The population genetic structure of the neon damselfish (Pomacentrus coelestis) in the northwestern Pacific Ocean was revealed by the hypervariable control region of the mitochondrial gene (343 bp). In total, 170 individuals were sampled from 8 localities distributed between Taiwan and Japan, and 71 haplotypes were obtained through sequence alignment. High haplotype diversity (= 0.956 ± 0.008) with low nucleotide diversity (π = 0.010 ± 0.006) was observed, and the results of the mismatch distribution test suggested that a historical population expansion after a period of population bottleneck might have occurred among P. coelestis populations. Based on the results of the UPGMA tree and AMOVA (Φct = 0.193, < 0.05) analyses, fish populations from eight localities could be divided into two groups: one includes populations from localities around mainland Japan, and the other includes those from Okinawa and southern Taiwan. A genetic break was found between populations from mainland Japan and Okinawa, and this break was congruent with the pattern of phenotypic variations documented in previous studies. This evidence supports the latitudinal variation of reproductive traits among P. coelestis populations likely being genetically based. It is suggested that the changes in sea level and sea surface temperatures during past glaciations might have resulted in population bottlenecks in P. coelestis and the modern populations in the northern West Pacific are likely the results of recolonization after such events. The Kuroshio Current acts not only as a vehicle for larval transport along its pathway (between populations in southern Taiwan and Okinawa) but also as a barrier for larval dispersal across the Kuroshio axis (between populations in mainland Japan and Okinawa). Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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