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971.
972.
针对开征环境税对高污染行业的影响,选取湖南省邵阳市为研究区域,以COD排放为例,选择了COD排放量最多的造纸及纸制品业、农副食品加工业、化学原料和化学制品制造业,调查各行业的废水治理成本。通过调查发现行业平均治理成本差别较大,从1.55元/kg到8.11元/kg,调查时点区域排污费收费标准0.7元/kg,相比行业平均治理成本太低,就几乎不具有激励减排的功能,同时也不具备筹集环境治理资金的功能。通过分析湖南邵阳高COD排放行业征收环境税的影响发现,无论基于行业废水平均治理成本制定环境保护税税率,还是考虑边际治理成本提高的情况下制定环境保护税税率,对行业大部分企业利税影响率均小于5%。而且基于行业治理成本征税,有利于淘汰行业中高污染的落后产能,促进行业整体资源优化配置,从长远来看有利于整个行业的发展,对于推动供给侧改革,改善环境质量具有重要意义。 关键词: 环境税;影响分析;高污染行业;供给侧改革  相似文献   
973.
水体污染遥感监测的可行性分析   总被引:7,自引:0,他引:7  
地面水体污染监测技术向空间遥感监测方向的拓展,在常规的监测技术基础上增添了新的观察角度,同时也反映出在应用现代遥感新技术的过程中,面临着需要不断加强改进和提高遥感监测精确度的处理方法。虽然遥感技术可以较大程度地改善常规性区域跨度和时效性方面的不足,但是现阶段通过遥感技术所能够采集到的水质信息及其图像判读,无论是在硬件技术上还是在软件技术上,都仍然存在较大的潜力空间有待于进一步开拓,从实际应用的可操作性程度分析,遥感技术对水体污染监测在精度方面仍然难以完全替代地面人工的局部监测过程。遥感探测过程和图像处理判读等有关的研究成果表明,即使是对水污染特征值显像比较突出的水质项目,目前在地面监测与遥感空间探测之间仍然需要通过相互对照验证和互相补充,才能更精确地全面调查地表水体污染状况,因此客观认识遥感过程及其可应用范围,对于切实地分析水体污染遥感监测的具体问题具有重要的现实意义。  相似文献   
974.
Feeding a growing population exceeding 1 billion is a big challenge to the Chinese government and has partly led to the self-sufficient policy in grain production and supply for decades. However, the efforts to push grain production everywhere have resulted in not only deterioration of the environment but also stagnation or even reduction in farmers' income as production costs continue to increase. This situation might be worsening after China's accession to the WTO that provides market access for bulk commodity imports. A sustainable development in Chinese agriculture depends on diversification, or structural adjustment, that allows Chinese farmers to fully utilize their comparative advantage in production of labor-intensive goods. Past experience has shown that diversification has contributed more than a half of the growth in Chinese agriculture during the reform period and reduced stresses on the environment at the same time. It is likely to contribute even more to Chinese agriculture in the future an  相似文献   
975.
垃圾卫生填埋技术   总被引:21,自引:1,他引:21  
介绍我国第一座现代化城市生活垃圾卫生填埋场-深圳市下坪固体废弃物填埋场的卫生填埋技术设施,如防渗设施、垃圾渗沥液导流设施、场外排水设施和场内清污分流设施等;垃圾卫生填埋工艺技术及作业方法,如分区分层填埋法、单元作业法和高效作业法;垃圾填埋场的环境监测项目及监测成果。  相似文献   
976.
探讨了博罗县下村农场坡地赤红壤的结构特征及其生产意义。结果表明,下村农场坡地赤红壤的质地较粗,土壤的团聚体含量较高,土壤的孔隙性较差;土壤粘粒、有机质,尤其是后者对土壤结构状况影响很大,土壤结构系数与土壤粘粒含量呈显著正相关,土壤1—0.05mm粗微团聚体含量、10—0.25mm水稳性团聚体及其几何平均直径值,均与土壤有机质含量呈显著正相关。坡地土壤的开发利用,应注意防治水土流失,减少团聚体的破坏,并特别注重提高土壤有机质含量,以改善土壤结构状况。  相似文献   
977.
• Adding kaolin/zeolite promotes the formation of stable heavy metals. • The potential ecological risk index of co-pyrolysis biochar is extremely low. • Increasing the pyrolysis temperature reduces the leaching toxicity of heavy metals. • The toxicity of biochar reduces with the increasing content of stable heavy metals. Pyrolysis is a promising technique used for treating of sewage sludge. However, the application of pyrolysis products is limited due to the presence of heavy metals. In this study, sewage sludge mixed with kaolin/zeolite was pyrolyzed in a rotary kiln, aiming to improve the immobilization of heavy metals in pyrolytic carbon. The total concentrations, speciation distributions, leaching toxicities, and potential ecological risk indices of heavy metals in pyrolysis biochar were explored to examine the effects of kaolin/zeolite and pyrolytic temperature on immobilizing heavy metals. Further, mineral composition and surface morphology of biochar were characterized by X-ray diffraction and scanning electron microscopy to reveal the potential mechanism of immobilizing heavy metals. Increasing pyrolysis temperature facilitated the stabilization of heavy metals in pyrolysis biochar. The proportions of stable heavy metals in biochar obtained at 650℃ were 54.50% (Cu), 29.73% (Zn), 79.29% (Cd), 68.17% (Pb) and 86.70% (Cr). Compared to sewage sludge, the potential contamination risk index of pyrolysis biochar obtained at 650℃ was reduced to 17.01, indicating a low ecological risk. The addition of 7% kaolin/zeolite further reduced the risk index of co-pyrolysis biochar prepared at 650℃ to 10.86/15.28. The characterization of biochar revealed that increase in the pyrolysis temperature and incorporation of additives are conducive to the formation of stable heavy metal-inorganics. This study demonstrates that the formation of stable mineral compounds containing heavy metals is the key to stabilizing heavy metals in pyrolysis biochar.  相似文献   
978.
• The sampling was conducted in city on the Yunnan-Guizhou Plateau for one year. • The groups of PAHs revealed their different environmental fates and migration paths. • Seasonal biomass burning could affect the concentration by long-distance transport. • Industrial sources and traffic emissions were the main contributor of PAHs. • Living in industrial areas or winter had higher health risk by exposure PAHs in PM2.5. Monthly particle-phase ambient samples collected at six sampling locations in Yuxi, a high-altitude city on the edge of Southeast Asia, were measured for particle-associated PAHs. As trace substances, polycyclic aromatic hydrocarbons (PAHs) are susceptible to the influences of meteorological conditions, emissions, and gas-particulate partitioning and it is challenging job to precise quantify the source and define the transmission path. The daily concentrations of total PM2.5-bound PAHs ranged from 0.65 to 80.76 ng/m3, with an annual mean of 11.94 ng/m3. Here, we found that the concentration of PM2.5-bound PAHs in winter was significantly higher than that in summer, which was mainly due to source and meteorology influence. The increase of fossil combustion and biomass burning in cold season became the main contributors of PAHs, while precipitation and low temperature exacerbated this difference. According to the concentration variation trend of PM2.5-bound PAHs and their relationship with meteorological conditions, a new grouping of PAHs is applied, which suggested that PAHs have different environmental fates and migration paths. A combination of source analysis and trajectory model supported local sources from combustion of fossil fuel and vehicle exhaust contributed to the major portion on PAHs in particle, but on the Indochina Peninsula the large number of pollutants emitted by biomass burning during the fire season would affect the composition of PAHs through long-range transporting. Risk assessment in spatial and temporal variability suggested that citizens living in industrial areas were higher health risk caused by exposure the PM2.5-bound PAHs than that in other regions, and the risk in winter was three times than in summer.  相似文献   
979.
总石油烃(total petroleum hydrocarbons, TPH)是烃总量的一个表征,包含各种烃类化合物,对人体具有极大的危害.通过对四川省某润滑油厂拆迁场地采样调查,分析了污染物分布特征,在明确未来规划用途的条件下,用分馏法以高碳石油烃毒性参数对污染地块的石油烃进行了风险评估.结果表明,场地主要污染物为石油烃C10~C40,主要污染区域为生产车间、室外原油堆放区、油桶堆放区、油罐堆放区和废水处理池.不同功能区石油烃C10~C40垂直分布特征不同,同一土壤层不同功能区域石油烃C10~C40污染程度也不同.对不同组成成分的石油烃C10~C40进行风险评估,其评价结果也不同.总的来说HI(脂肪族∶芳香族含量比为100∶0)<HI(脂肪族∶芳香族含量比为79.4∶20.6)<HI(脂肪族∶芳香族含量比为0∶100).当脂肪族∶芳香族含量比为100∶0和79.4∶20.6时,石油烃C10~C40总危害商<1,石油烃C10~C40浓度在人体健康可接受的范围内,不需要进行土壤风险控制值计算;当脂肪族∶芳香族含量比为0∶100时,石油烃C10~C40总危害商>1,存在非致癌风险;综合非致癌效应的土壤风险控制值为8 168.58 mg·kg-1 .  相似文献   
980.
为了探讨甲苯仔任时铁屑降解三氯乙烯(TCE)的有效性及影响因素,考察了铁屑粒径、铁屑预处理方法及甲苯初始质量浓度对TCE降解效果的影响。实验结果表明:选用粒径0.35—0.83mm的铁屑较好;用0.05mol/L的盐酸清洗后的铁屑对TCE的降解效果好于未进行酸洗的铁屑对TCE的降解效果;当m(甲苯):m(TCE)分别为0,1.2,10.3,18.6时,TCE降解的反应速率常数分别为0.0691,0.0595,0.0458,0.0361h^-1,半衰期分别为10.03,11.65,15.13,19.20h,即随着甲苯初始质量浓度的提高,TCE降解的反应速率常数变小,半衰期变长;铁屑对甲苯具有吸附作用,甲苯的初始质量浓度越高,甲苯吸附量越大。  相似文献   
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