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为了贯彻国家的可持续发展战略,更有效地解决中国的环境危机以及更好地进行中国的生态文明建设,就必须建立底线思维.中央第十八届三中全会通过的《中共中央关于全面深化改革若干重大问题的决定》明确规定了要划定生态保护红线.通过对生态保护红线的相关文献和政策进行分析,提出生态红线的类型和划定的思考,结合生态红线落地问题,对宁夏生态红线划定中存在的问题进行思考,以期为全国生态红线划定和生态保护提供参考. 相似文献
614.
International cooperation to address climate change now stands at a crossroads.With a new international regime for emissions reduction established by the Durban Platform, "New Climate Economics(NCE)" has become a research hotspot.The need for urgent action to combat climate change has prompted discussion on reforms of economic growth patterns and the energy system.The industrial civilization,therefore,now faces a transition towards a new pathway for ecological sustainability.NCE explores new economic concepts,theories,and analytical methods to design a balanced pathway for sustainable growth and emission reduction.Instead of getting trapped in discussions on allocation of emission reduction responsibilities and obligations among countries,NCE pays more attention to developing win-win multilateral cooperation mechanisms that facilitate collaborative RD and knowledge sharing.In addition,NCE studies incentives for low-carbon transition,turning carbon emission reduction into a domestic need for countries to increase their international competitiveness.To achieve the 2°C target,most countries around the world face challenges of insufficient emission allowances to cover expected emissions associated with their projected economic growth.As carbon emissions rights becomes an increasingly scarce resource,increasing the carbon productivity of the economy turns to be the critical path to address the dilemma of green or growth.NCE studies the historical evolution of carbon productivity for countries at different development stages as well as ways to enhance such carbon productivity.This type of study provides invaluable lessons for emerging economies to reach their own emission peaks without losing the momentum of growth.Replacing fossil fuels with new and renewable energy has proven to be an inevitable choice for reshaping the energy system and addressing climate change- it has already become a global trend.NCE studies incentives for new energy technology innovation and deployment provided by carbon pricing,and sheds light on the co-benefits of climate change mitigation,such as resource conservation,environmental protection,and energy security.The role of carbon pricing in promoting intemational RD cooperation and technical transfer will also be studied.The shift in consumption patterns is another key factor enabling a low-carbon transformation.Therefore,NCE also explores the theoretical work on new values of wealth,welfare and consumption,new lifestyles in the context of ecological civilization,concepts and implementation of low-carbon urban planning in developing countries,and the impacts of consumption pattern changes on social development,material production,and urban infrastructure construction. 相似文献
615.
The establishment of a global multi-regional carbon market is considered to be a cost effective approach to facilitate global emission abatement and has been widely concerned.The ongoing planned linkage between the European Union’s carbon market and a new emission trading system in Australia in 2015 would be an important attempt to the practice of building up an international carbon market across different regions.To understand the abatement effect of such a global carbon market and to study its energy and economic impact on different market participants,this article adopts a global dynamic computable general equilibrium model with a detailed representation of the interactions between energy and economic systems.Our model includes 20 economic sectors and 19 regions,and describes in detail 17 energy technologies.Bundled with fossil fuel consumptions,the emission permits are considered to be essential inputs in each of the production and consumption activities in the economic system to simulate global carbon market policies.Carbon emission permits are endogenously set in the model,and can be traded between sectors and regions.Considering the current development of the global carbon market,this study takes 2020 as the study period.Four scenarios(reference scenario,independent carbon market scenario,Europe Union(EUh-Australia scenario,and China-EU-Australia scenario) are designed to evaluate the impact of the global carbon market involving China,the EU,and Australia.We find that the carbon price in the three countries varies a lot,from $32/tCO2 in Australia,to $17.5/tCO2 in the EU,and to $10/tCO2 in China.Though the relative emission reduction(3%) in China is lower than that in the EU(9%) and Australia(18%),the absolute emission reduction in China is far greater than that in the EU and Australia.When China is included in the carbon market,which already includes the EU and Australia,the prevailing global carbon price falls from $22 per ton carbon dioxide(CO2) to $12/tCO2,due to the relatively lower abatement cost in China.Seventy-one percent of the EU’s and eighty-one percent of Australia’s domestic reduction burden would be transferred to China,increasing 0.03%of the EU’s and 0.06%of Australia’s welfare.The emission constraint improves the energy efficiency of China’s industry sector by 1.4%,reduces coal consumption by3.3%,and increases clean energy by 3.5%. 相似文献
616.
准确的水生生态风险评价需要可靠的毒性数据,而其获取要求在一定时间范围内,水体中污染物的浓度保持恒定。对疏水性有机污染物进行水体生物毒性测试时,通常采用有机溶剂加标,然而该方式可能因为污染物的挥发和降解、容器壁吸附、生物摄取等问题,水体中污染物浓度持续下降,导致污染物的浓度-效应关系难以明确。近期为了克服这些问题,被动加标用于替代溶剂加标,通过污染物在加标体系中平衡分配来维持精确和恒定的水体浓度,同时还可通过测定加标聚合物中污染物的浓度来监测水体浓度。首先介绍了被动加标方法及其材料选择,讨论了该方法在生态风险评价中的主要应用,包括分配系数的测定、体外细胞测试、体内生物积累及毒性测试,以及沉积物毒性评价等。然后,以测定代表污染物多氯联苯在聚二甲基硅氧烷与水间的分配系数为例,详细说明被动加标的操作流程。最后,讨论了被动加标方法的优缺点,并对其在水生生态风险中的应用前景进行了展望。 相似文献
617.
He Z Cade-Menun BJ Toor GS Fortuna AM Honeycutt CW Sims JT 《Journal of environmental quality》2007,36(4):1086-1095
Both enzymatic hydrolysis and solution (31)P nuclear magnetic resonance (NMR) spectroscopy have been used to characterize P compounds in animal manures. In this study, we comparatively investigated P forms in 0.25 M NaOH/0.05 M EDTA extracts of dairy and poultry manures by the two methods. For the dairy manure, enzymatic hydrolysis revealed that the majority of extracted P was inorganic P (56%), with 10% phytate-like P, 9% simple monoester P, 6% polynucleotide-like P, and 18% non-hydrolyzable P. Similar results were obtained by NMR spectroscopy, which showed that inorganic P was the major P fraction (64-73%), followed by 6% phytic acid, 14 to 22% other monoesters, and 7% phosphodiesters. In the poultry manure, enzymatic hydrolysis showed that inorganic P was the largest fraction (71%), followed by 15% phytate-like P and 1% other monoesters, and 3% polynucleotide-like P. NMR spectroscopy revealed that orthophosphate was 51 to 63% of extracted P, phytic acid 24 to 33%, other phosphomonoesters 6 to 12%, and phospholipids and DNA 2% each. Drying process increased orthophosphate (8.4% of total P) in dairy manure, but decreased orthophosphate (13.3% of total P) in poultry manure, suggesting that drying treatment caused the hydrolysis of some organic P to orthophosphate in dairy manure, but less recovery of orthophosphate in poultry manure. Comparison of these data indicates that the distribution patterns of major P forms in animal manure determined by the two methods were similar. Researchers can utilize the method that best fits their specific research goals or use both methods to obtain a full spectrum of manure P characterization. 相似文献
618.
用清洁生产的理念防治农业污染的初步探讨 总被引:6,自引:0,他引:6
农业发展面临的农业污染问题,已成为制约农业可持续发展的"瓶颈".农业污染问题已经成为影响农村经济发展,以及农村社会和谐发展的重要因素之一.在论述农业清洁生产涵义的基础上,探讨了农业清洁生产防治农业污染问题.以新疆绿洲农业为例,论述了农业污染现状及发展农业清洁生产的必要性,分析探讨了发展农业清洁生产存在的问题和障碍,并提出了对策和建议. 相似文献
619.
目前,土壤重金属污染形势严峻,而微生物辅助植物修复的措施以其绿色友好的特性备受关注,其中,研发高效的微生物菌剂对提高修复效率至关重要.针对一种能代谢植物激素脱落酸(ABA)的微生物—樊庆生红球菌(Rhodococcus qingshengii)进行菌剂制备研究,并验证其对超积累植物东南景天提取重金属镉(Cd)、铜(Cu)、镍(Ni)和锌(Zn)能力的强化效果.结果表明,该菌种制备优化条件为:80%麦麸∶15%锯末∶5%活性炭;料水比1∶2、pH=9;接菌量40%;培养温度30℃、培养时间3 d、烘干温度40℃.优化后,固体菌剂有效活菌数可达2×1012CFU·g-1,与土壤混合后其有效活菌数峰值达1×1011CFU·g-1,是接种相同活菌数液体菌剂的4倍,30 d保有的有效活菌数是液体菌剂的23倍.与未配施的空白相比,该菌剂配施于不同重金属污染土壤中,可使东南景天的Cd含量提高110%~260%,Ni和Zn含量分别提高约100%和90%;生物富集因子(BCF)则提高50%~500%,转运系数(TF)... 相似文献
620.
河湖交错区是鄱阳湖流域重金属污染物进入湖泊的主要通道,也是重金属富集的场所.本文通过在鄱阳湖河湖交错区采集软体动物样品,分析样品的肌肉和内脏中铁(Fe)、锰(Mn)、铜(Cu)、锌(Zn)、铬(Cr)、镍(Ni)、砷(As)、镉(Cd)、铅(Pb)和锑(Sb)的含量,利用生物-沉积物累积因子和碳氮稳定同位素对鄱阳湖软体动物重金属的富集特征及营养结构和食源关系进行研究,并利用综合目标危险系数进行健康风险评估.结果表明:①鄱阳湖软体动物重金属含量存在显著的种间和组织间的差异,且受体长体重的稀释作用,与所在栖息地的关系不大,但与区域背景环境存在明显的对应关系,均低于水产限量标准值.软体动物对重金属Cu、Zn和Cd具有明显的富集能力,蚌(圆顶珠蚌、三角帆蚌、背瘤丽蚌和褶纹冠蚌)易从环境中富集更多的Mn和Cd,而螺(铜锈环棱螺和大沼螺)则易富集Cu和Zn;②软体动物δ13C值为-29.84‰~-21.13‰,δ15N值为4.09‰~11.51‰,螺和蚌存在明显不同的食物来源.软体动物中的重金属并不随δ15N值的变化表现出显著的改变,但与δ13C值存在显著的线性关系;其中Cu和Zn与δ13C值表现为显著的正相关关系,而Mn、Cr、As、Cd、Pb和Sb表现为显著的负相关关系;③健康风险评估结果表明,不论是成人还是儿童,综合目标危险系数(TTHQ) 均大于1,表明鄱阳湖河湖交错区软体动物重金属的富集会对人群食用产生较为显著的健康风险,其中Mn和As是主要的贡献者,且食用蚌的风险略高于螺.研究结果可为鄱阳湖水生态安全、水生生物多样性保护及食品安全评估提供科学依据和理论支撑. 相似文献