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941.
微塑料(MPs)是污水处理厂中普遍检出的新兴污染物之一,目前研究主要集中于传统污水处理系统的污染水平及分布特征,但有关微塑料暴露对污泥颗粒化过程的研究鲜见报道.为探究微塑料对污泥颗粒化的诱导影响,选用环境中广泛检出的聚对苯二甲酸乙二醇酯微塑料(PET-MPs)作为研究对象,通过微塑料暴露试验研究PET-MPs对污泥造粒过程中系统潜能、胞外聚合物(EPS)组成和菌群富集特征的影响.结果表明,PET-MPs暴露显著加快污泥颗粒化进程,同时以蛋白质(PN)为主导的EPS含量上升会增强污泥表面疏水性,造粒速度和EPS分泌量与暴露粒径成正比,微塑料和EPS协同促进颗粒污泥的形成.然而微塑料持续暴露会导致系统除污性能恶化,250μm PET-MPs暴露下亚硝酸盐氮积累的负面影响最严重,浓度高达(5.08±0.24)mg·L-1.高通量测序结果进一步表明,变形菌门(Proteobacteria)和拟杆菌门(Bacteroidota)是促进颗粒污泥形成的主要优势门;红环菌科(Rhodocyclaceae)、鞘氨醇杆菌科(Sphingomonadaceae)、黄杆菌科(Flavob... 相似文献
942.
为了研究清洁取暖措施对保定市PM2.5中碳质气溶胶浓度和来源的影响,于2014年和2019年冬季采暖期在保定市采集PM2.5样品,用DRI Model 2001A热光碳分析仪测定样品中OC和EC的浓度.结果表明,2014年采暖期PM2.5中ρ(OC)和ρ(EC)平均值分别为60.92μg·m-3和18.15μg·m-3,2019年采暖期PM2.5中ρ(OC)和ρ(EC)平均值分别为36.63μg·m-3和6.07μg·m-3,与2014年相比2019年OC、 EC浓度分别下降了39.87%和66.56%,EC下降幅度大于OC,且2019年气象条件与2014年相比更不利于污染物扩散.通过对OC和EC相关性分析和SOC估算,发现2014年和2019年保定市OC和EC相关性R2分别为0.874和0.811,表明保定市OC和EC具有较为一致的来源.2014年和2019年ρ(SOC)的平均值分别为16... 相似文献
943.
准确判断臭氧(O3)生成敏感性对O3污染成因分析和防控对策的制定至关重要.首次利用响应曲面方法设计最优试验方案,基于盒子模式模拟结果,快速量化O3对其前体物变化的响应.结果表明,CO对O3有正贡献,NOx和VOCs与O3呈现显著非线性关系,当φ(VOCs)与[φ(NOx)-13.75]比值大于4.17时,为NOx控制区,小于4.17时,为VOCs控制区;烯烃为影响O3生成的关键VOCs组分,当φ(烯烃)与[φ(NOx)-15]比值小于1.10且φ(烯烃)<35×10-9时,烯烃有利于O3的生成.响应曲面法在多因素和其交互作用对O3生成影响的研究中取得了良好效果,为高效判断O3敏感性提供了新的思路和方法. 相似文献
944.
当前我国同时面临改善生态环境质量和实现碳达峰碳中和两大战略任务,协同推进减污降碳已成为我国经济社会发展全面绿色转型的必然选择,电力部门在转型过程中将发挥重要作用.面向不同的电力需求情景,构建低成本实现碳达峰、碳中和的多目标模型,求解得出减污降碳协同增效最优路径方案.结果表明,在如期实现碳达峰、碳中和目标的前提下,减污和降碳协同性较好,两者协同控制可高效助力低碳转型的实现;优化电力部门发电结构是实现减污降碳协同增效的关键措施,研究期火电占比不断下降,清洁电力占比超过92.5%;不同电力需求下二氧化碳和主要大气污染物排放量有明显差异,其中二氧化碳排放量受电力需求影响最大,低电力需求、中等电力需求和高电力需求情景下峰值二氧化碳排放量分别为94.16亿、 104.09亿和107.46亿t,主要污染物二氧化硫、氮氧化物和颗粒物的排放同样表现出在低电力需求、中等电力需求和高电力需求情景下依次递增的趋势.电力需求的提高仅增加了电力部门内部发电结构调整的压力,未影响到其他部门的产量和活动水平,即电力需求导致的电力部门减排压力未表现出部门间传递的趋势. 相似文献
945.
中国碳排放及影响因素的市域尺度分析 总被引:1,自引:1,他引:0
评估区域碳排放及其与社会经济状况的关系对于制定碳减排措施至关重要.以中国339个地级及以上城市(不含新疆部分城市和港澳台地区)为研究对象,探究了非化石能源占比、土地开发度、常住人口城镇化率、第二产业占比、人均GDP和人均建设用地面积对人均CO2排放量的影响.通过构建模拟人均CO2排放量的贝叶斯信念网络,识别各因素对人均CO2排放量的全局影响;采用多尺度地理加权回归模型,分析各因素对人均CO2排放量的局部影响.结果表明:(1)2020年,中国地级及以上城市人均CO2排放量呈现出由南向北递增,东部沿海向内陆递减的格局.(2)从全局来看,人均CO2排放量对各因素的敏感性从高到低依次为:人均建设用地面积>人均GDP>常住人口城镇化率>土地开发度>第二产业占比>非化石能源占比.(3)从局部来看,各因素与人均CO2排放量的空间关系方向与全局关系一致,关系强度上存在空间异质性.(4)清洁能源、脱碳技术、土地节约集约利用... 相似文献
946.
Zhuang Yahui Zhang Hongxun Wang Xiaoke & Fang JinyunResearch Center for Eco-Environmental Sciences 《中国人口.资源与环境(英文版)》2004,2(2)
This report summarizes the surveys on carbon inventories and initiatives on sustainable carbon cycling taken by RCEES. The first part of this report deals with the concept of sustainable carbon cycling, the historical evolution of carbon cycling processes in China, carbon pool enhancement, value addition, carbon sequestration and carbon balance. The second part covers the modeling of carbon dynamics, emission inventories of various carbon containing greenhouse gases and their potential abatement measures. 相似文献
947.
Liette Vasseur Lise Lafrance Colette Ansseau Dominique Renaud Daniel Morin Thérèse Audet 《Environmental management》1997,21(3):359-365
/ It has been suggested that the general public should be moreinvolved in environmental policy and decision making. It is important forthem to realize that they will have to live with the consequences ofenvironmental policies and decisions. Consequently, policy makers shouldconsider the concerns and opinions of the general public before makingdecisions on environmental issues. This raises questions such as: How can weintegrate the perceptions and reactions of the general population inenvironmental decisions? What kind of public participation should weconsider? In the present study, using a new regional ecosystem model, weattempted to integrate these aspects in its decision making model byincluding the formation of an advisory committee to resolve problems relatedto waste management. The advisory committee requested the activeparticipation of representatives from all levels of the community: economic,municipal, and governmental intervenors; environmental groups; and citizens.Their mandates were to examine different management strategies available inthe region, considering all the interdisciplinary aspects of each strategy,elaborate recommendations concerning the management strategies that are mostsuitable for all, and collaborate in communication of the information to thegeneral population. The results showed that at least in small municipalitiessuch an advisory committee can be a powerful tool in environmental decisionmaking. Conditions required for a successful consultation process, such aseveryday lay language and the presence of a facilitator other than ascientific expert, are discussed.KEY WORDS: Public consultation; Environmental policies;Interdisciplinary aspects; Municipal sewage sludge management; Generalpopulation; Decision-making process 相似文献
948.
Baranchikov Yu. N. Perevoznikova V. D. Vishnyakova Z. V. 《Russian Journal of Ecology》2002,33(6):398-401
In the southern-taiga low grass–green moss fir forest completely defoliated by the Siberian moth, the rate of soil respiration in the third year after the pest population outbreak was 1.5 times higher than in an undisturbed tree stand. This was explained by a significant increase in the abundance and activity of soil microorganisms in the pest-defoliated forest, which occurred due to the qualitative changes in the litter composition and the increased temperature and moisture in the upper soil layers. The rate of carbon emission from the soil in the defoliated forest was 41.7 kg/ha per day, compared to 28.3 kg/ha per day in the undisturbed fir forest. 相似文献
949.
Elements of carbon balance of oligotrophic bogs were studied using an example of the landscape profile of the Klyuch River in 1998–2000. Carbon balance was preliminarily calculated taking into account the biological productivity, release of carbon dioxide and methane, and carbon outflow with bog waters. Based on the data obtained on the carbon inflow and outflow, the conclusion was made concerning the progressive peat formation in the region studied. 相似文献
950.
Robert A. Pikanowski 《Chemistry and Ecology》1992,6(1):199-212
Disposal of sewage sludge in the New York Bight Apex (12-Mile Dump Site) ceased at the end of December 1987. Previous efforts to quantify the effects of sludge were hindered by the inability to obtain true replication. the cessation of dumping afforded the opportunity to apply the technique of replication in time, also known as a Before/After, Control/Impact design. Conditionally, this method allows one to separate treatment effects from the natural differences that confound many environmental impact studies. the Environmental Processes Division of the Northeast Fisheries Center, National Marine Fisheries Service sampled the benthic environment of the New York Bight Apex from June 1986 through September 1989 using a sample design based on the technique of replication in time.
Three dominant species (rock crab, Cancer irroratus; little skate; Raja erinacea; and winter flounder, Pseudopleuronectes americanus) and total demersal finfish, collected by otter trawl, showed no statistically significant response to the cessation of disposal. American lobster (Homarus americanus) increased in local abundance, but this result was possibly confounded by a change in fishing effort. 相似文献
Three dominant species (rock crab, Cancer irroratus; little skate; Raja erinacea; and winter flounder, Pseudopleuronectes americanus) and total demersal finfish, collected by otter trawl, showed no statistically significant response to the cessation of disposal. American lobster (Homarus americanus) increased in local abundance, but this result was possibly confounded by a change in fishing effort. 相似文献