中国土地沙漠化、水土流失和盐渍化的原因和驱动力:总体分析

论文收集了102篇沙漠化、79篇水土流失和64篇盐渍化的案例研究(共245篇),运用总体分析方法,把造成3种生态环境问题的因素归结为四类原因(农业扩张、资源利用、基础设施建设和自然因素)和五类驱动因子(经济、制度、技术、文化和人口)。分析结果表明,生态环境问题绝大多数由多因子所引起;在原因层面上,对沙漠化、水土流失和盐渍化案例影响最频繁的因子分别是农业扩张因子(92%)、资源利用因子(90%)和自然因素(86%);从驱动因子的层面上看,对沙漠化、水土流失和盐渍化案例影响最频繁的都是经济因素,影响频率分别为86%、81%和89%;总体来看,在发生生态环境问题的区域中,往往以经济因素的影响最为常见(85%),其次为技术(69%)和人口因素(62%)。因此,不适当地发展经济是造成我国沙漠化、水土流失和盐渍化日益严重的重要原因。     

“碳税问题”的国内研究现状

从碳税的内涵、理论渊源、碳税的影响、碳税税制设计问题与实施框架四方面入手,对国内学术界关于我国碳税问题的研究文献进行系统整理与分析,从而了解国内学术界关于碳税问题的主要研究成果,并在此基础上进行评述。研究认为：碳税开征将从宏观经济与微观经济两个层面对我国经济体系产生影响,这种影响既有正面也有负面。这就要求我国政府在碳税税制设计和实施路线上积极协调．从而达到节能减排与经济发展之间的平衡。     

广西沿海地区海洋生态环境保护状况及对策建议

广西近岸海域具有丰富的海洋资源和重要的海洋生态系统,在开发利用海洋资源、发展经济的同时,广西各级政府历来都非常注重海洋生态环境保护和监控,作了大量卓有成效的工作。根据目前广西沿海地区海洋生态环境保护状况,结合沿海各市的国民经济与社会发展规划,分析广西沿海地区主要海洋生态环境问题,针对存在的主要问题及当前社会经济快速发展的实际情况,提出海洋生态环境保护对策建议。     

声化学氧化－间歇式活性污泥法处理染料废水的研究

介绍了声化学氧化反应机理。采用声化学氧化法作预处理，可使生物难降解的靛兰染料废水的ＢＯＤ＿５／ＣＯＤ由０．２１—０．２３提高到０．４４—０．５１，再经间歇式活性污泥法处理后，各项水质指标均符合ＧＢ８９７８—８８《污水综合排放标准》。     

我国城市污泥中重金属的赋存形态与生态风险评价

为全面了解中国城市污水处理厂脱水污泥中重金属（HMs）的形态特征和污染状况,本研究以我国40座城市污水处理厂的剩余污泥为研究对象,对污泥中重金属As、Cd、Cr、Cu、Ni、Pb和Zn的总量以及赋存形态进行了测定.采用毒液浸出法（TCLP）、风险评价编码法（RAC）和潜在生态风险指数法评价了其生态风险.结果表明,40个样品中重金属含量的中位值由大到小依次为：Zn > Cu > Cr > Pb > Ni > As > Cd,各元素整体达标率>90%.As的各形态分布较为平均;Cd和Zn以可还原态为主;Cr主要以残渣态的形式存在,其次为可氧化态和可还原态;Cu主要以可氧化态的形式存在;Ni主要以可交换态的形式存在;Pb主要以可还原态和残渣态的形式存在,可交换态的含量最低.TCLP提取态重金属的比例大小顺序为：Ni > As > Zn > Cd > Cu > Cr,所有样品中Pb的TCLP提取态含量均低于检出限;RAC法评价结果显示,7种重金属环境风险大小依次为：Ni > As > Zn > Cd > Cu > Cr > Pb,Ni的生态风险等级为高等,Zn、As和Cd的生态风险等级为中等,Cr和Cu的生态风险等级为低等,Pb无生态风险;潜在生态风险评价结果表明,城市污泥中Cd和Cu的潜在生态风险最高,是我国城市污泥中主要的重金属污染物,但是如果按照国家标准规定的方法进行农用,造成土壤污染的风险总体处于较低水平.     

春节除夕燃放烟花爆竹对环境空气质量影响分析

结合2003—2014年南京城区春节除夕前后主要空气污染物监测数据,分析烟花爆竹集中燃放时空气污染指数及PM10、SO2、NO2质量浓度的变化趋势。指出除夕燃放烟花爆竹会引起PM10、SO2、NO2质量浓度上升,在大气扩散条件不佳的情况下影响了环境空气质量。建议在大中城市城区采取适当的禁放措施,并加快研制安全环保型的烟花爆竹替代产品。     

Food contamination as a pathway for lead exposure in children during the 2010–2013 lead poisoning epidemic in Zamfara, Nigeria

In 2010, an estimated 400 to 500 children died of acute lead poisoning associated with artisanal gold mining in Zamfara, Nigeria. Processing of gold ores containing up to 10% lead within residential compounds put residents, especially children, at the highest risk. Principal routes of exposure were incidental ingestion and inhalation of contaminated soil and dusts. Several Nigerian and international health organizations collaborated to reduce lead exposures through environmental remediation and medical treatment. The contribution of contaminated food to total lead exposure was assessed during the environmental health response. Objectives of this investigation were to assess the influence of cultural/dietary habits on lead exposure pathways and estimate the contribution of contaminated food to children's blood lead levels(BLLs). A survey of village dietary practices and staple food lead content was conducted to determine dietary composition, caloric intakes, and lead intake. Potential blood lead increments were estimated using bio-kinetic modeling techniques. Most dietary lead exposure was associated with contamination of staple cereal grains and legumes during post-harvest processing and preparation in contaminated homes. Average post-harvest and processed cereal grain lead levels were 0.32 mg/kg and 0.85 mg/kg dry weight, respectively. Age-specific food lead intake ranged from 7 to 78 μg/day. Lead ingestion and absorption were likely aggravated by the dusty environment, fasting between meals, and nutritional deficiencies. Contamination of staple cereal grains by highly bioavailable pulverized ores could account for as much as 11%–34% of children's BLLs during the epidemic, and were a continuing source after residential soil remediation until stored grain inventories were exhausted.     

Trends and gaps in biodiversity and ecosystem services research: A text mining approach

Understanding the relationship between biodiversity conservation and ecosystem services concepts is essential for evidence-based policy development. We used text mining augmented by topic modelling to analyse abstracts of 15 310 peer-reviewed papers (from 2000 to 2020). We identified nine major topics; “Research & Policy”, “Urban and Spatial Planning”, “Economics & Conservation”, “Diversity & Plants”, “Species & Climate change”, “Agriculture”, “Conservation and Distribution”, “Carbon & Soil & Forestry”, “Hydro-& Microbiology”. The topic “Research & Policy” performed highly, considering number of publications and citation rate, while in the case of other topics, the “best” performances varied, depending on the indicator applied. Topics with human, policy or economic dimensions had higher performances than the ones with ‘pure’ biodiversity and science. Agriculture dominated over forestry and fishery sectors, while some elements of biodiversity and ecosystem services were under-represented. Text mining is a powerful tool to identify relations between research supply and policy demand.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01776-2.     

Moving from trends to benchmarks by using regression tree analysis to find inbreeding thresholds in a critically endangered bird

Understanding how inbreeding affects endangered species in conservation breeding programs is essential for their recovery. The Hawaiian Crow (‘Alalā) (Corvus hawaiiensis) is one of the world's most endangered birds. It went extinct in the wild in 2002, and, until recent release efforts starting in 2016, nearly all of the population remained under human care for conservation breeding. Using pedigree inbreeding coefficients (F), we evaluated the effects of inbreeding on Hawaiian Crow offspring survival and reproductive success. We used regression tree analysis to identify the level of inbreeding (i.e., inbreeding threshold) that explains a substantial decrease in ‘Alalā offspring survival to recruitment. Similar to a previous study of inbreeding in ‘Alalā, we found that inbreeding had a negative impact on offspring survival but that parental (vs. artificial) egg incubation improved offspring survival to recruitment. Furthermore, we found that inbreeding did not substantially affect offspring reproductive success, based on the assumption that offspring that survive to adulthood breed with distantly related mates. Our novel application of regression tree analysis showed that offspring with inbreeding levels exceeding F = 0.098 were 69% less likely to survive to recruitment than more outbred offspring, providing a specific threshold value for ongoing population management. Our results emphasize the importance of assessing inbreeding depression across all life history stages, confirm the importance of prioritizing parental over artificial egg incubation in avian conservation breeding programs, and demonstrate the utility of regression tree analysis as a tool for identifying inbreeding thresholds, if present, in any pedigree-managed population.     

Relative influence of environmental factors and fishing on coral reef fish assemblages

Understanding whether assemblages of species respond more strongly to bottom-up (availability of trophic resources or habitats) or top-down (predation pressure) processes is important for effective management of resources and ecosystems. We determined the relative influence of environmental factors and predation by humans in shaping the density, biomass, and species richness of 4 medium-bodied (10–40 cm total length [TL]) coral reef fish groups targeted by fishers (mesopredators, planktivores, grazer and detritivores, and scrapers) and the density of 2 groups not targeted by fishers (invertivores, small fish ≤10 cm TL) in the central Philippines. Boosted regression trees were used to model the response of each fish group to 21 predictor variables: 13 habitat variables, 5 island variables, and 3 fishing variables (no-take marine reserve [NTMR] presence or absence, NTMR size, and NTMR age). Targeted and nontargeted fish groups responded most strongly to habitat variables, then island variables. Fishing (NTMR) variables generally had less influence on fish groups. Of the habitat variables, live hard coral cover, structural complexity or habitat complexity index, and depth had the greatest effects on density, biomass, and species richness of targeted fish groups and on the density of nontargeted fishes. Of the island variables, proximity to the nearest river and island elevation had the most influence on fish groups. The NTMRs affected only fishes targeted by fishers; NTMR size positively correlated with density, biomass, and species richness of targeted fishes, particularly mesopredatory, and grazing and detritivorous fishes. Importantly, NTMRs as small as 15 ha positively affected medium-bodied fishes. This finding provides reassurance for regions that have invested in small-scale community-managed NTMRs. However, management strategies that integrate sound coastal land-use practices to conserve adjacent reef fish habitat, strategic NTMR placement, and establishment of larger NTMRs will be crucial for maintaining biodiversity and fisheries.