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1.
分别于2013年10月和2014年2月、5月、7月在贵阳市城区3个环境空气质量监测国控点位(南明区市监测站、云岩区黔灵公园马鞍山和观山湖区贵阳一中)进行PM10、PM2.5样品采集,并对10种水溶性离子(SO42-、NO2-、NO3-、NH4+、Cl-、F-、Na+、K+、Mg2+、Ca2+)的含量进行了分析。结果表明,研究时段内,贵阳市3个点位PM10、PM2.5平均质量浓度分别为(64.8±25.5)、(46.6±21.2)μg/m3。其中,云岩区黔灵公园马鞍山点位的颗粒物浓度最低,南明区市监测站点位最高。3个点位PM2.5平均浓度与PM10平均浓度的比值为0.719,表明贵阳市城区PM10中,PM2.5占主导地位。水溶性离子分析显示,SO42-、NO2-、NO3-、NH4+、Cl-、F-、Na+、K+主要分布在PM2.5中,Mg2+、Ca2+主要分布在PM10中。3个点位PM10和PM2.5中的水溶性离子均表现为SO42-、NH4+、Ca2+浓度较大,F-、NO2-较小,表明3个点位的污染源总体相同,且水溶性离子占PM10、PM2.5含量的比例达33.6%~48.1%。贵阳市城区大气中的SO2转化率在5月、7月、10月较高,2月最低,主要是由于5月、7月、10月的高温、高湿、强辐射环境条件促进了SO2向SO42-的转化。阴阳离子平衡分析表明,贵阳市城区PM10、PM2.5呈现出偏碱性的特征。水溶性离子主成分分析表明,贵阳市城区PM10中的水溶性离子主要来源于城市扬尘、生物质燃烧尘、煤烟尘、建筑尘以及二次粒子,PM2.5中水溶性离子的来源与PM10较为相似。 相似文献
2.
对2020年4月—2021年3月北京市建成区挥发性有机物(VOCs)的化学特征、污染来源及其对臭氧(O3)污染的影响进行了研究。结果显示:O3日最大8 h滑动平均值在臭氧季(4—9月)均值为134 μg/m3,是非臭氧季(10月至次年3月)均值(59.6 μg/m3)的2.2倍。臭氧季VOCs体积浓度均值为14.3×10-9,明显低于非臭氧季(21.1×10-9),可能与光化学反应速率和VOCs来源的季节性差异有关。臭氧生成潜势(OFP)贡献率排名前10位的物种在臭氧季和非臭氧季相似,均包括间/对-二甲苯、甲苯、乙烯、邻二甲苯、异戊烷、正丁烷、丙烯、反式-2-丁烯和1,2,4-三甲基苯,但排名有所差异,燃煤源特征明显的乙烯等物种在非臭氧季上升明显,与溶剂使用、油气挥发相关的间/对二甲苯、甲苯、异戊烷和正丁烷等物种在臭氧季上升明显。甲苯/苯的值和异戊烷/正戊烷的值在臭氧季明显高于非臭氧季,反映出机动车排放和油气挥发等在臭氧季影响突出,非臭氧季是燃煤影响显著。基于正交矩阵因子分解模型(PMF),臭氧季解析出机动车尾气排放(40.9%)、溶剂使用(20%)、油气挥发(16.4%)、工业排放(17.6%)和植物排放(5.1%)等5种污染源;非臭氧季解析出机动车尾气(38.9%)、燃烧源(26.3%)、工业排放(17.8%)和溶剂使用(17%)等4种污染源。 相似文献
3.
2016—2017年武汉市城区大气PM2.5污染特征及来源解析 总被引:1,自引:0,他引:1
利用2016年1月至2017年9月湖北省环境监测中心站大气复合污染自动监测站的在线监测数据,对武汉市城区PM2.5的污染特征及主要来源进行解析。结果表明,武汉市城区PM2.5质量浓度呈现出明显的季节差异,季节变化规律为冬季>春季>秋季>夏季。水溶性离子的主要成分SO42-、NO3-和NH4+占总离子质量浓度的82.0%。PM2.5中阴离子相对阳离子较为亏损,颗粒整体呈碱性。夏季气态污染物的氧化程度较高且SO2较NO2氧化程度高。后向轨迹分析结果表明,区域传输是武汉市PM2.5的一个重要来源,在4个典型重污染阶段,武汉市分别受到局地、东北、西北及西南方向气团传输的影响。PMF模型解析出武汉市PM2.5五大主要来源及平均贡献率:扬尘22.0%、机动车排放27.7%、二次气溶胶21.6%、重油燃烧14.9%和生物质燃烧13.8%。 相似文献
4.
Joana Garrido Nogueira Ronaldo Sousa Hassan Benaissa Geert De Knijf Sónia Ferreira Mohamed Ghamizi Duarte V. Gonçalves Richard Lansdown Catherine Numa Vincent Prié Nicoletta Riccardi Mary Seddon Maria Urbańska Alice Valentini Ilya Vikhrev Simone Varandas Amílcar Teixeira Manuel Lopes-Lima 《Conservation biology》2021,35(5):1367-1379
Theidentification of key biodiversity areas (KBA) was initiated by the International Union for Conservation of Nature in 2004 to overcome taxonomic biases in the selection of important areas for conservation, including freshwater ecosystems. Since then, several KBAs have been identified mainly based on the presence of trigger species (i.e., species that trigger either the vulnerability and or the irreplaceability criterion and thus identify a site as a KBA). However, to our knowledge, many of these KBAs have not been validated. Therefore, classical surveys of the taxa used to identify freshwater KBAs (fishes, molluscs, odonates, and aquatic plants) were conducted in Douro (Iberian Peninsula) and Sebou (Morocco) River basins in the Mediterranean Biodiversity Hotspot. Environmental DNA analyses were undertaken in the Moroccan KBAs. There was a mismatch between the supposed and actual presence of trigger species. None of the trigger species were found in 43% and 50% of all KBAs surveyed in the Douro and Sebou basins, respectively. Shortcomings of freshwater KBA identification relate to flawed or lack of distribution data for trigger species. This situation results from a misleading initial identification of KBAs based on poor (or even inaccurate) ecological information or due to increased human disturbance between initial KBA identification and the present. To improve identification of future freshwater KBAs, we suggest selecting trigger species with a more conservative approach; use of local expert knowledge and digital data (to assess habitat quality, species distribution, and potential threats); consideration of the subcatchment when delineating KBAs boundaries; thoughtful consideration of terrestrial special areas for conservation limits; and periodic field validation. 相似文献
5.
Juan Tao Chengzhi Ding Jinnan Chen Liuyong Ding Sébastien Brosse Jani Heino Virgilio Hermoso Ruidong Wu Ziwang Wang Jiaxin Hu Rongxiao Che Xiaowei Jin Songhao Ji Dekui He 《Conservation biology》2023,37(3):e14036
The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43–0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25–29% of fish habitats, 16–23% of species, and 30–31% of priority conservation areas. Moreover, 6–21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered. 相似文献
6.
Amanda S. Cicchino Andrea E. Weinberg Laura B. Sample McMeeking Meena M. Balgopal 《Conservation biology》2023,37(2):e14023
Scientists in higher education institutions around the globe recognize the importance of engaging with public stakeholders to share their enthusiasm, explain their science, and encourage primary and secondary students to enter the sciences. However, without direct consideration of students’ and teachers’ perspectives and interests, scientists may design activities around their own goals, limiting the impact on school stakeholders (i.e., students, teachers, paraprofessional staff, students’ parents, and other caregivers). We drew from natural and social science research to describe how expanding the conception of place beyond the biophysical can help engage school stakeholders in meaningful ways. We describe the multidimensional PLACE framework that we developed to integrate perspectives, knowledge, and values of all stakeholders in engagement programming. The framework is organized around topics that stakeholders should discuss early on to ensure successful partnerships. We recommend that scientists identify and use pedagogy that is inclusive; language framed around dialogic communication methods; aims and motivations centered on engagement; cultural funds of knowledge of place (i.e., disciplinary, personal, or experiential knowledge); and evaluation of engagement based on meaningful metrics. Two case studies are presented to illustrate how the PLACE framework components, when addressed, can lead to robust, successful partnerships between scientists and schools. 相似文献
7.
固定源排污许可证监测管理制度研究 总被引:5,自引:2,他引:3
依靠排污许可证管理,固定源执行由行业排放标准为主正逐步过渡到"国家行业排放标准——单一源排放标准"双层排放标准,并以执行更全面和精准的单一源排放标准为主,对应的监测要求及考核方式更加多样化。对监测管理制度进行设计,明确固定源制定自行监测方案和守法监测的主体责任,厘清许可证核发部门、属地监测、执法部门的监管职责。系统设计"固定源制定并提交自行监测方案-核发部门审核-方案纳入排污许可证中成为规定-依规定自行监测和记录-固定源提交执行报告-监管部门审计式审核-执法监测和执法检查"的全过程管理机制,设计标准化的监管计划程序落实证后监管与执法监测,明晰监管部门的有限责任。 相似文献
8.
9.
Andrew D. M. Dobson E. J. Milner-Gulland Colin M. Beale Harriet Ibbett Aidan Keane 《Conservation biology》2019,33(3):665-675
The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols’ own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort (CPUE) against patrol effort (CPUE-E). We devised a simple, mechanistic model of law breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences under different temporal patterns of enforcement effort. The CPUE-E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (ΔCPUE-ΔE) reliably identified deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The ΔCPUE-ΔE plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE-E plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data and to consider appropriate (and poaching-activity-specific) intervals for aggregation. They also reveal important gaps in understanding of deterrence in this context, especially the mechanisms by which it occurs. In practical applications, we recommend the use of ΔCPUE-ΔE plots in preference to other basic metrics and advise that deterrence should be suspected only if there is a clear negative slope. Distinct types of illegal activity should not be grouped together for analysis, especially if the signs of their occurrence have different persistence times in the environment. 相似文献
10.
Island species are difficult to conserve because they face the synergy of climate change, invasive species, deforestation, and increasing human population densities in areas where land mass is shrinking. The Caribbean island of Hispaniola presents particular challenges because of geopolitical complexities that span 2 countries and hinder coordinated management of species across the island. We employed species distribution modeling to evaluate the impacts of climatic change and anthropogenic activities on the distribution of an endemic mammal of conservation concern, the Hispaniolan solenodon (Solenodon paradoxus). We aggregated occurrence points for this poorly known species for the Last Glacial Maximum (LGM) and the present (1975–2016) based on museum collections, online biodiversity databases, and new field surveys. We quantified degree of overlap between periods and scenarios with Schoener's D. Through a conservation paleobiology lens, we found that over time humans played an increasing role in shaping the distribution of S. paradoxus, thus, providing a foundation for developing conservation strategies on appropriate spatiotemporal scales. Human population density was the single most important predictor of S. paradoxus occurrence. Densities >166 people/km2 corresponded to a near-zero probability of occurrence. Models that accounted for climate but not anthropogenic variables falsely identified suitable habitat in Haiti, where on-the-ground surveys confirm habitat is unavailable. Climate-only models also significantly overestimated the potential for habitat connectivity between isolated populations. Our work highlights that alternative fates for S. paradoxus in the Anthropocene exist across the political border between the Dominican Republic and Haiti due to the fundamentally different economic and political realities of each country. Relationships in the fossil record confirm that Hispaniola's sociopolitical boundary is not biologically significant but instead represents one imposed on the island's fauna in the past 500 years by colonial activity. Our approach reveals how a paleontological perspective can contribute to concrete management insights. 相似文献