Review of LCA studies of solid waste management systems – Part I: Lessons learned and perspectives

The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste, e.g. construction and demolition waste. Waste management practitioners are thus encouraged to abridge these gaps in future applications of LCA. In addition to this contextual analysis, we also evaluated the findings of selected studies of good quality and found that there is little agreement in the conclusions among them. The strong dependence of each SWMS on local conditions, such as waste composition or energy system, prevents a meaningful generalisation of the LCA results as we find it in the waste hierarchy. We therefore recommend stakeholders in solid waste management to regard LCA as a tool, which, by its ability of capturing the local specific conditions in the modelling of environmental impacts and benefits of a SWMS, allows identifying critical problems and proposing improvement options adapted to the local specificities.     

Water saving effect on integrated water resource management

This study proposes an improved integrated water resource management (IWRM), in which water conservation was analyzed for the entire water use process. A multi-objective optimization method was applied to optimize the IWRM, which investigated the reduction of freshwater consumption and the total water supply cost. Customer's preference for saving water and an end use analysis (EUA) was applied in the water conservation analysis. Taking Tianjin as the study area, a reduction in customer's economic pressure (EP) was utilized to evaluate the degree of the customer's preference for saving water. The results revealed that agriculture had a greater preference for saving water than other sectors, where as the public had the weakest motivation for saving water. Improving the transportation method could contribute 62.1% of the total water savings in the agriculture sector. The optimization of the IWRM demonstrated that the local freshwater savings would be 21.5%, and the total cost for water supplies would decrease by 13%. However, a government subsidy of 87.5 million Yuan would be needed. Additionally, by analyzing the change in the amount of water savings affected by water price, the appropriate water price increase range was suggested to be 1.5–1.7 times the original price.     

Local Perceptions of Changes in Traditional Ecological Knowledge: A Case Study from Malekula Island,Vanuatu

Traditional ecological knowledge (TEK) is a critical global resource that may be eroding amid social and environmental change. Here, we present data on local perceptions of TEK change from three communities on Malekula Island in Vanuatu. Utilizing a structured interview (n = 120), we find a common perception of TEK loss. Participants defined two key periods of TEK erosion (roughly 1940–1960 and 1980–present), and noted that TEK decline was driven both external (e.g., church) and internal (e.g., shifting values) processes. Erosion was perceived to more comprehensive in the worldview domain than in aspects of ethnobiological knowledge and practice. These data indicate the perceived fragility of TEK systems and the complexity of TEK change. TEK systems are critical to natural resource management, and data such as these will assist in designing nuanced responses to the ongoing loss of cultural knowledge and practice.     

Targeted Application of Seasonal Load Duration Curves Using Multivariate Analysis in Two Watersheds Flowing Into Lake Houston1

Teague, Aarin, Philip B. Bedient, and Birnur Guven, 2011. Targeted Application of Seasonal Load Duration Curves Using Multivariate Analysis in Two Watersheds Flowing Into Lake Houston. Journal of the American Water Resources Association (JAWRA) 47(3):620‐634. DOI: 10.1111/j.1752‐1688.2011.00529.x Abstract: Water quality is a problem in Lake Houston, the primary source of drinking water for the City of Houston, Texas, due to pollutant loads coming from the influent watersheds, including Spring Creek and Cypress Creek. Statistical analysis of the historic water quality data was developed to understand the source characterization and seasonality of the watershed. Multivariate analysis including principal component, cluster, and discriminant analysis provided a custom seasonal assessment of the watersheds so that loading curves may be targeted for season specific pollutant source characterization. The load duration curves have been analyzed using data collected by the U.S. Geologic Survey with corresponding City of Houston water quality data at the sites to characterize the behavior of the pollutant sources and watersheds. Custom seasons were determined for Spring Creek and Cypress Creek watersheds and pollutant source characterization compared between the seasons and watersheds.     

夏、冬季降雨中溶解性有机质(DOM)光谱特征及来源辨析

利用紫外-可见光谱与三维荧光光谱,结合拉格朗日混合单粒子轨道模型及火点图,研究了重庆2013年夏、冬两季雨水DOM光谱特征,并对其来源进行解析.结果表明,雨水DOM与水体、土壤DOM具有类似性质光谱特征,证明降雨DOM也是陆地及水环境中DOM地化特征的重要贡献者.雨水DOM中DOC含量为0.88~12.80 mg·L-1,CDOM含量在3.17~21.11m-1之间,夏、冬两季降雨DOM差异明显(P0.05).与夏季相比,冬季降雨DOM分子量较小,芳香性程度较低,腐殖化程度也更低,输入主要以本地和短距离输送为主;而夏季DOM来源较分散.尽管吸收和荧光光谱可用于解析雨水DOM组成和来源,但在光谱特征的解析和来源识别上与其他来源DOM有所区别,传统"内、外源区分"并不适用于雨水DOM.     

福建省重点城市路面尘负荷及化学组成研究

采集并分析了福建省重点城市厦门、漳州、泉州和莆田城区具有代表性的57个地面扬尘和16个土壤样品的26种无机元素、8种水溶性离子和碳成分等组成.不同城市粒径≤100μm的路面尘负荷平均值在6.99 g.m-2与10.11 g.m-2之间,而粒径≤2.5μm的路面尘(PM2.5)负荷平均值在4.0 mg.m-2和12.5 mg.m-2之间.不同城市土壤尘和路面尘PM2.5中浓度最高的元素都是Si、Ca、Al、Fe和K,路面尘中Ca元素明显富集,而主要人为来源的重金属元素如Cu、Pb、Zn、Cr在路面尘PM2.5中的浓度显著高于土壤尘.漳州城区路面尘PM2.5中二次离子NH4+、NO3-和SO24-的含量明显高于其它地区,厦门、漳州和泉州城区路面尘PM2.5中Mg2+和Ca2+之间都存在显著的正相关关系.四城市路面尘中有机碳(OC)的含量均高于济南、石家庄以及北京地面扬尘OC的含量,元素碳(EC)的含量均低于北京地区路面扬尘EC的含量.泉州和莆田两地OC和EC的相关性较好,说明路面尘中OC和EC有相同或相似的来源.质量平衡结果显示泉州和莆田路面尘PM2.5中含量最高的是土壤尘,其次为有机物.按化学组成特征对路面尘PM2.5进行聚类解析,得到受大气沉降影响、受土壤尘影响、受大气沉降和土壤尘共同作用以及受土壤尘和建筑尘共同作用4类样品.     

宁波三江口水域原核生物群落结构分析

首次应用16S rRNA基因-Illumina Miseq高通量测序技术对甬江流域宁波三江口区域的表层水体原核生物群落进行了分析,共获得215 504条高质量序列.多样性指数分析表明,该流域的水体原核生物群落具有较高的遗传多样性和丰富度.菌群分类分析发现,β-变形菌纲(β-Proteobacterium)、放线菌门(Actinobacteria)和拟杆菌门(Bacteroidetes)是主要的优势菌群,其相对丰度占总群落的78.88%.对比不同站位的原核生物群落,发现水文环境可能是影响三江口水域原核生物群落组成和结构的重要因素之一.与以往报道对比分析表明,甬江流域分布有多种污水和粪便污染指示菌,其中余姚江污染指示菌的丰度最高,说明其受污染的风险可能较高.病原菌BLASTN分析表明,在种和亚种水平上,分别检出76和18种潜在病原菌,占序列总量的2.19%和0.40%.本研究为系统认识甬江流域原核生物群落结构及生态功能提供了重要基础数据.     

采用颜色空间表征ANAMMOX启动与冲击过程

厌氧氨氧化(ANAMMOX)是一种高效、节能的脱氮技术,但是其启动过程和稳定状态的表征目前仍缺乏一个简单易行的方法.针对这一问题,在水质分析的基础上,采用颜色空间重点监测ANAMMOX启动过程中污泥的颜色变化,并借助高通量测序技术对微生物菌群的种类和数量等进行分析.结果表明:(1)根据水质特征,整个启动过程可分为活性迟滞期、活性增强期、负荷提高期、稳定运行期.与此同时,HSV、CIELAB颜色空间的指标,整体上呈现先降低后升高的趋势,然后保持稳定.污泥颜色的变化与水质的变化以及分子生物学特征中优势菌群的变迁一致,因此,三者之间具有相关性,进而表明,采用颜色空间可对ANAMMOX启动过程进行准确表征;(2)当遇到高负荷引起的冲击时,H、S、a~*、b~*、C_(ab)~*等指标与总无机氮(TIN)容积去除速率均呈现降低的趋势,而H_(ab)出现了突升,但均能准确反映出系统的冲击特性.提出了基于颜色空间表征ANAMMOX启动各阶段的方法并建立了一套冲击过程指标体系,为颜色空间在ANAMMOX系统中的应用提供了理论基础.     

夏季太湖CDOM光学特性空间差异及其来源解析

为进一步探究夏季太湖CDOM（有色溶解性有机质）光学特性在空间分布上的差异性与其来源的关系,对其紫外-可见吸收及三维荧光光谱特性进行了分析研究,在此基础上进一步分析了CDOM吸尘系数及其荧光组分（C1、C2、C3、C4）强度和各水质参数间的相关性.结合主成分分析法探讨了CDOM的来源以及与各参数指标[ρ（DOC）除外]之间的来源关系.结果表明:CDOM吸收系数α（355）、S值（光谱斜率）变化范围分别为3.27~8.27 m-1和0.011~0.021 nm-1;太湖西部、北部及南部湖区CDOM丰度较大,S值较低,受陆源输入的影响较为明显.CDOM的三维荧光光谱揭示其中含有两种类蛋白质组分C1和C2以及类腐殖质组分C3和C4,并且以类蛋白质组分为主.此外,大部分采样点的荧光指数（FI）为1.70~2.01,自生源指数（BIX）大于1,腐殖化指数（HIX）小于0.6,r_（T/C）（荧光峰T与荧光峰C荧光强度比值）小于2,表明夏季太湖CDOM内源特性相对强烈.研究显示,除ρ（DOC）外,CDOM与其他水质参数在第一主成分上（贡献率为90.8%）均存在显著相关关系,说明各水质参数的来源存在相似性,并且受生物自生源影响更为显著.      

基于主成分分析法的陕北地区可持续发展对比研究

基于可持续发展基本理论,选取60项指标建立陕北地区可持续发展评价指标体系,采用软件SPSS(19.0)进行主成分分析,分别对延安市、榆林市2000—2014年的可持续发展水平、可持续发展潜力和可持续发展协调度进行动态对比分析。结果表明延安市、榆林市发展基本趋于一致:可持续发展水平较高,但可持续发展潜力明显不足,可持续发展协调度较低;制约其可持续发展的主要因素在于资源发展动力不足、产业结构单一、环境的恶化及治理的低效。