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Three decades of changes in water environment of a large freshwater Lake and its relationship with socio-economic indicators

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Journal of Environmental sciences 2019年第3期31卷 156-166页

作者： Cuicui Li Weiying Feng Fanhao Song Zhongqi He Fengchang Wu Yuanrong Zhu John P.Giesy Yingchen Bai Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of sciences State Key Laboratory of Environmental Criteria and risk Assessment Chinese Research Academy of Environmental Sciences USDA-ARS Southern Regional Research Center Department of Biomedical Veterinary sciences and Toxicology Centre University of Saskatchewan

Tai Lake(Ch: Taihu) has attracted international attention forcyanobacteria ***, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The results of research demonstrate how socioeconomic development affected quality of water and how it has been improved by anthropogenic activities. This study described variability in indicators of water quality in Tai Lakeand investigated thedrivers. Significant relationships existed between concentrations of annual mean total nitrogen(TN), total phosphorous(TP), chemical oxygen demand(COD) and biological oxygen demand(BOD), and population, per capital gross domestic production(GDP) and sewage discharge(p < 0.05). However, mechanisms causing change varied among TN, TP, COD and BOD. Before 2000, the main contributors to increases in concentrations of TN were human population, GDP and volumes of domestic sewage discharges. After 2000, discharges of industrial sewage become the primary contributor. After 1998, the regressions of annual mean TN, TP and COD on per capital GDP, population and domestic sewage discharge were reversed compared to the former period. Since 1999, an apparent inverted U-shaped relationship between environmental pollution and economic development has developed, which indicated that actions taken by governments have markedly improved quality of water in Tai Lake. The statistical relationship between BOD and per capital GDP didn't conform to the Kuznet curve. The Ushaped Kuznet curve may offer hope for the future that with significant environmental investments a high GDP can be reached and maintained without degradation of the environment, especially through appropriate management of industrial sewage discharge.

关键词： Eutrophic lake Water environment indicators Population GDP Sewage discharge Asia

On a Dual risk Model Perturbed by Diffusion with Dividend Threshold

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Chinese Annals of Mathematics,Series B 2016年第5期37卷 777-792页

作者： Hui ZHI Jiangyan PU School of Mathematical sciences Fudan University School of international Finance Shanghai Finance University

In the dual risk model, the surplus process of a company is a L′evy process with sample paths that are skip-free downwards. In this paper, the authors assume that the surplus process is the sum of a compound Poisson process and an independent Wiener process. The dual of the jump-diffusion risk model under a threshold dividend strategy is discussed. The authors derive a set of two integro-differential equations satisfied by the expected total discounted dividend until ruin. The cases where profits follow an exponential or mixtures of exponential distributions are solved. Applying the key method of the Laplace transform, the authors show how the integro-differential equations are solved. The authors also discuss the conditions for optimality and show how an optimal dividend threshold can be calculated as well.

关键词： exponential surplus admissible assume Laplace Poisson until Wiener derive continuity

Impact of emission control on regional air quality: An observational study of air pollutants before, during and after the Beijing Olympic Games

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Journal of Environmental sciences 2014年第1期26卷 175-180页

作者： Shulan Wang Jian Gao Yuechong Zhang Jingqiao Zhang Fahe Cha Tao Wang Chun Ren Wenxing Wang State Key Laboratory of Environmental Criteria and risk Assessment Chinese Research Academy of Environmental Sciences Department of Civil and Structrual Engineering The Hong Kong Polytechnic University

An observational study on trace gases and PM2.5 was conducted at three sites in and around Beijing, during the Olympic season from 2007 to 2009. Air quality improved significantly during the Olympic Games due to the special emission control measures. However, concentrations of the primary pollutants and PM were found to have risen significantly after the Games. Although the major O3 precursors （NOx and VOCs） were well controlled during the Olympic season, O3 was still found to be the highest in 2008, based on the data of ground-based observation. All this information suggests that while control of regional emissions for the Beijing Olympic Games did improved the air quality in Beijing, more efforts will be needed for the continuous improvement of regional air quality, especially for significant reductions of O3 and fine particulate pollution, and not only in Beijing, but also in the B eijing-Tianjin-Hebei region.

关键词： Beijing Olympic Games primary pollutants ozone fine particle air

Characteristics of atmospheric particles and heavy metals in winter in Chang-Zhu-Tan city clusters, China

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Journal of Environmental sciences 2014年第1期26卷 147-153页

作者： Kai Zhang Fahe Chai Zilong Zheng Qing Yang Juansheng Li Jing Wang Yujie Zhang State Key Laboratory of Environmental Criteria and risk Assessment Chinese Research Academy of Environmental Sciences Shandong University of Science and Technology Changsha Environmental Protection College

To understand the pollution characteristics of atmospheric particles and heavy metals in winter in Chang-Zhu-Tan city clusters, China, total suspended particulate （TSP） and PMI0 samples were collected in cities of Changsha, Zhuzhou and Xiangtan from December 2011 to January 2012, and heavy metals of Cd, Pb, Cr, and As were analyzed. It shows that the average TSP concentration in Changsha, Zhuzhou and Xiangtan were （183 ± 73）, （201± 84） and （190 ±66） μg/m3 respectively, and the average PM10 were （171 ± 82）, （178 ± 65） and （179 ± 55） μg/m3 respectively. The lowest TSP and PM10 concentrations occurred at the background Shaping site of Changsha. The average ratio of p（PM10）/p（TSP） was 91.9%, ranging from 81.3% to 98.9%. Concerning heavy metals, in TSP samples, the concentration of Cr, As, Cd and Pb were 28.8-56.5, 18.1-76.3, 3.9-26.1 and 148.0-460.9 ng/m3, respectively, while in PMI0 samples, were 16.4--42.1, 15.5-67.9, 3.3-22.2 and 127.9-389.3 ng/m3, respectively. The enrichment factor of Cd was the highest, followed by Pb and As, while that of Cr was the lowest.

关键词： atmospheric particles pollution characteristics enrichment factors Chang-Zhu-Tan city clusters

Carbon Sequestration Effects of Shrublands in Three-North Shelterbelt Forest Region, China

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Chinese Geographical Science 2014年第4期24卷 444-453页

作者： LIU Wenhui ZHU Jiaojun JIA Quanquan ZHENG Xiao LI Junsheng LOU Xuedong HU Lile State Key Laboratory of Environmental Criteria and risk Assessment Chinese Research Academy of Environmental Sciences Institute of Applied Ecology Chinese Academy of Sciences Key Laboratory of Forest Cultivation Department of Forest Sciences Beijing Forestry University

Three-North Shelterbelt Forest （TSF） program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that： 1） The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10^7 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2） In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo vat. heterophylla. The carbon sequestration of/-/, rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3） The total carbon sequestration of shrubland in the study region was 4.5 x 107 Mg C with a mean annual carbon sequestration of 1.5× 10^6 Mg C. The carbon density in the four sub-regions decreased in the following order： the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a base

关键词： biomass biomass density carbon density carbon sequestration carbon sequestration rate carbon storage Three-NorthShelterbelt Forest (TSF)

Soil contamination with antibiotics in a typical peri-urban area in eastern China: Seasonal variation, risk assessment, and microbial responses

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Journal of Environmental sciences 2019年第5期31卷 200-212页

作者： Fangkai Zhao Lei Yang Liding Chen Qian Xiang Shoujuan Li Long Sun Xinwei Yu Li Fang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of sciences Key Laboratory of Health risk Factors for Seafood of Zhejiang Province Zhoushan Municipal Center For Disease Control and Prevention

The prevalence and persistence of antibiotics in soils has become an emerging environmental issue and an increasing threat to soil security and global public health. The problem is more severe in areas undergoing rapid urbanization; however, the ecological risks of antibiotics,seasonal variability, and associated soil microbial responses in peri-urban soils have not been well-explored. The seasonal soil sampling campaigns were conducted in a typical peri-urban watershed in eastern China to investigate distribution of antibiotics. The results demonstrated higher mean concentrations of most antibiotic compounds in winter than in summer in periurban soils. The seasonal variations of norfloxacin, enrofloxacin, and ciprofloxacin were more significant than those of other antibiotics, due to their higher migration ability and *** ecological risk assessment demonstrated that chlortetracycline, ciprofloxacin, doxycycline,and ofloxacin can pose high risks to soil microorganisms. Furthermore, the coexistence of multiple antibiotics obviously poses higher risks than individual compounds. A redundancy analysis demonstrated that tetracyclines mainly showed negative correlations with Firmicutes and Chloroflexi, and quinolones showed obviously negative correlations with Acidobacteria,Gemmatimonadetes, and Nitrospirae, suggesting potential inhibition from antibiotics on biological activities or biodegradation processes. However, the persistence of antibiotics in soil results in a significant decrease in bacterial diversity and a change in dominant *** results provide an overview of the seasonal variability of antibiotics and the associated effects on bacterial communities in peri-urban soils. The results can provide scientific guidance on decreasing soil contamination with antibiotics to enhance soil security in similar areas.

关键词： Antibiotics Soil Seasonal variation Ecological risks Bacterial community

Integrated biomarkers in wild crucian carp for early warning of water quality in Hun River, North China

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Journal of Environmental sciences 2014年第4期26卷 909-916页

作者： Binghui Zheng Kun Lei Ruizhi Liu Shuangshuang Song Lihui An State Key Laboratory of Environmental Criteria and risk Assessment & State Environmental Protection Key Laboratory of Estuarine and Coastal Research Chinese Research Academy of Environment Sciences

Metabolizing enzymes play important roles in the detoxification of various pollutants in aquatic organisms, thereby they can also be used to provide early-warning signals of environmental risks. Real-time quantitative reverse-transcription polymerase chain reaction assays were developed to quantify cytochrome P450 1A （CYP1A）, superoxide dismutase （SOD）, glutathione peroxidase （GPx）, catalase （CAT）, and glutathione-S-transferase （GST） in crucian carp （Carassius auratus）. The methods were then used to detect the respective mRNA expression levels in liver tissue in wild crucian carp from the Hun River, North China. CYP1A mRNA expression was significantly up-regulated in fish from stations $5, $6, and $8 （p 〈 0.05）. SOD mRNA expression was significantly down-regulated in downstream areas relative to fish from upstream sites （p 〈 0.05）; GPx and CAT mRNA expression levels were also down-regulated at $9 （p 〈 0.05）. In contrast, GST mRNA expression showed no obvious change between fish collected from up- or downstream areas of the river. Finally, an integrated biomarker response was used to evaluate the integrated impact of pollutants in the Hun River and allow better comprehension of the real toxicological risk of these investigated sites.

关键词： real-time quantitative reverse- transcription polymerase chain reaction Carassius auratus Hun River integrated biomarker response water quality

An overview of representation theorems for static risk measures

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Science China Mathematics 2009年第7期52卷 1412-1422页

作者： SONG YongSheng YAN JiaAn Center for Financial Engineering and risk Management Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

In this paper,we give an overview of representation theorems for various static risk measures:coherent or convex risk measures, risk measures with comonotonic subadditivity or convexity, law-invariant coherent or conv... 详细信息

关键词： Choquet integral (concave) distortion law-invariant risk measure stochastic orders 46N10 60E05 60E15 91B28 91B30

Disaster risk Reduction,Climate Change Adaptation and Their Linkages with Sustainable Development over the Past 30 Years:AReview

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international Journal of Disaster risk Science 2023年第1期14卷 1-13页

作者： Jiahong Wen Chengcheng Wan Qian Ye Jianping Yan Weijiang Li School of Environment and Geographical sciences Shanghai Normal UniversityShanghai200234China Integrated risk Governance Project Beijing100875China Rodel risk Solutions Inc. TorontoONM1W1J3Canada

The severe damage and impacts caused by extreme events in a changing climate will not only make the sustainable development goals difficult to achieve,but also erode the hard-won development gains of the *** article reviews the major impacts and challenges of disaster and climate change risks on sustainable development,and summarizes the courses and linkages of disaster risk reduction(DRR),climate change adaptation(CCA),and sustainable development over the past 30 *** findings show that the conceptual development of DRR actions has gone through three general phases:disaster management in the 1990s,risk management in the 2000s,and resilient management and development in the ***,CCA has been widely implemented to overcome the adverse effects of climate change.A framework is proposed for tackling climate change and disaster risks in the context of resilient,sustainable development,indicating that CCA is not a subset of DRR while they have similarities and differences in their scope and *** is crucial to transform governance mechanisms at different levels,so as to integrate CCA and DRR to reduce disaster and climate change risks,and achieve safe growth and a resilient future in the era of the Anthropocene.

关键词： Climate change adaptation Disaster risk reduction Resilience Sustainable development goals United Nations