期刊文献+
共找到755篇文章
< 1 2 38 >
每页显示 20 50 100
Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake,North China:Concentrations,sources profiles and potential risk 被引量:43
1
作者 Guocheng Hu Xiaojun Luo +6 位作者 Fengchao Li Jiayin Dai Jianyang Guo Shejun Chen Cao Hong Bixian Mai Muqi Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期176-183,共8页
Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflow... Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China. Total concentrations of OCPs, PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng]g, 2.3 to 197.8 ng/g, and 101.3 to 6360.5 ng]g, respectively. The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake. For hexachlorocyclohexane (HCHs) and dichlorodiphenytrich/oroethanes (DDTs), α-HCH and p,p'-DDT were predominant isomers; while for PCBs, PCB 28/31, PCB 40/103, PCB 60, PCB 101, and PCB 118 were predominant congeners. Possible sources derived from historical usage for OCPs and incomplete combustion fuel, wood, and coal and exhaustion of boats or cars for PAHs. Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact. 展开更多
关键词 persistent organic pollutants CONCENTRATIONS profiles risk assessment baiyangdian Lake
下载PDF
Impact of transferred water on the hydrochemistry and water quality of surface water and groundwater in Baiyangdian Lake,North China 被引量:6
2
作者 Yong Zhao Jingyan Han +1 位作者 Bing Zhang Jiaguo Gong 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第3期104-112,共9页
The hydrochemical composition of surface water and groundwater is a key parameter for understanding the evolution of water and its quality.In particular,little is known about the impact of transferred water on surface... The hydrochemical composition of surface water and groundwater is a key parameter for understanding the evolution of water and its quality.In particular,little is known about the impact of transferred water on surface water and groundwater.In this study,Baiyangdian Lake was selected as a typical area for extensive groundwater exploration and surface water transfer in the North China Plain.Surface water and groundwater samples were sampled in dry/wet seasons and then analyzed before/after the water transfer,respectively.Generally,surface water and groundwater are extensively hydrologically connected based on hydrochemical evidence.It was found that the hydrochemical composition of the shallow groundwater is affected by the surface water and that the water quality of the deep groundwater is stable.However,inter-aquifer recharge processes from the shallow groundwater to the deep groundwater existed in the anthropogenic region impacted with high nitrate-ion concentrations.Also,the hydrochemical composition of the surface water and groundwater was dominated by rock-weathering and evaporation-precipitation processes.Due to the existence of the deep vadose zone in the alluvial fan,Na^(+)was exchanged into soil matrices during the leakage of the surface water.In addition,the transferred water resulted in surface water with good quality,and it also played as an important recharge source to groundwater.As the most important water resource for irrigation and drinking,deep groundwater should be paid more attention in the alluvial fan with frequent water transfer and extensive groundwater exploration. 展开更多
关键词 Hydrochemical composition Surface water GROUNDWATER Water transfer baiyangdian Lake
下载PDF
Hydrochemical characteristics and geochemistry evolution of groundwater in the plain area of the Lake Baiyangdian watershed,North China Plain 被引量:4
3
作者 ZHANG Yu-qin WANG Guang-wei +3 位作者 WANG Shi-qin YUAN Rui-qiang TANG Chang-yuan SONG Xian-fang 《Journal of Groundwater Science and Engineering》 2018年第3期220-233,共14页
Water cycle and water quality in the Lake Baiyangdian watershed of the North China Plain have undergone great changes due to over-pumping of groundwater and wastewater discharge.In this paper,hydrogeochemical data was... Water cycle and water quality in the Lake Baiyangdian watershed of the North China Plain have undergone great changes due to over-pumping of groundwater and wastewater discharge.In this paper,hydrogeochemical data was collected to analyze the hydrochemical characteristics and geochemistry evolution of groundwater.The study area was divided into two typical parts.One was in the upstream plain area,where over-pumping had resulted in significant decline of groundwater level;the other one was located in the downstream area near the Fu River and Lake Baiyangdian(Lake BYD region).In addition to the natural weathering of minerals,excessive fertilizer was also a main factor of higher ion concentration in groundwater.According to studies,due to good permeability,these regions were easy to be polluted even with deep groundwater depth.However,upstream shallow groundwater and surface water,including lake water,domestic along with industrial wastewater were all sources of present shallow groundwater in the Lake BYD region.Results indicated that anthropogenic activities rather than minerals much matter to the groundwater in these regions.Particularly,wastewater largely decided the groundwater quality,which suggested that the management and restoration of surface water quality was crucial to groundwater protection. 展开更多
关键词 Hydrochemical characteristics GEOCHEMICAL processes GROUNDWATER The LAKE baiyangdian WATERSHED North China PLAIN
下载PDF
Assessment of the Spatial and Temporal Water Eutrophication for Lake Baiyangdian Based on Integrated Fuzzy Method 被引量:3
4
作者 Shuxuan Liang Hong Wu +1 位作者 Hongbo Li Yihong Wu 《Journal of Environmental Protection》 2013年第1期120-125,共6页
Water quality evaluation entails both randomness and fuzziness. Considering that water eutrophication evaluation involves many indices, different classifications and interval values, fuzzy variable sets theory was dev... Water quality evaluation entails both randomness and fuzziness. Considering that water eutrophication evaluation involves many indices, different classifications and interval values, fuzzy variable sets theory was developed to Lake Baiyangdian as a study case. Taking reference to eutrophication standard of Chinese lakes and local characteristic of Lake Baiyangdian, eutrophication degree of lake was divided into 8 levels. Total phosphorus, total nitrogen, and CODMn were selected as evaluation indices in this research. Based on the measured data, index feature value matrix of sample was built. Index weights were determined by means of pure threshold value method. Relative membership degree of each index to each classification was calculated with relative difference function model. Then the stability of feature value of classification corresponding was received by the comprehensive calculation with the relative membership degree and index weights. The results show that the proposed models are effective tools for generating a set of realistic and flexible optimal solutions for complicated water quality evaluation issues. It concluded that the model was reasonable and practical. 展开更多
关键词 EUTROPHICATION Evaluation Fuzzy Method SPATIAL VARIATION TEMPORAL VARIATION LAKE baiyangdian
下载PDF
Cold-humid effect of Baiyangdian wetland
5
作者 Hui-yun LI Shi-guo XU Tao MA 《Water Science and Engineering》 EI CAS 2012年第1期1-10,共10页
关键词 baiyangdian wetland local climate cold-humid effect temperature regulation relative humidity
下载PDF
Initial Exploration on the Ecological Compensation Mechanism of Baiyangdian Watershed
6
作者 WANG Jun WANG Chen-xiao HE Hong-yan 《Meteorological and Environmental Research》 CAS 2012年第10期5-10,共6页
Establishment of the ecological compensation mechanism is one important way for solving a series of issues in Baiyangdian Watershed, including environment pollution, ecological deterioration, unsustained water supplem... Establishment of the ecological compensation mechanism is one important way for solving a series of issues in Baiyangdian Watershed, including environment pollution, ecological deterioration, unsustained water supplement, rural pollution aggravation and ecological migration. Based on the principles of main functional area, public goods, welfare economics, financial transfer payment and watershed management, we put forward the construction framework of ecological compensation mechanism in Baiyangdian Watershed. Compensation subject is governments at all levels and beneficiary within watershed. Compensation object is governments at all levels, eco-builder and victim within watershed. Compensation way in- dudes government-led and market-oriented and game-negotiation types. Compensation standard includes financial transfer payment, compensation between upstream and downstream of the watershed, rural environmental protection with collections of management fees and subsidies to co-gov- ernance, ecological migration and inter-basin section. The safeguard measures of implementation for ecological compensation mechanism in Baiy- angdian Watershed are setting legal system and status of the ecological compensation, ensuring special usage of the ecological compensation fund, carrying out performance evaluation index system, building social management system of the ecological compensation and promoting the reform of watershed manaQement structure. 展开更多
关键词 baiyangdian Watershed Ecological compensation mechanism China
下载PDF
Shrinking and Drying up of Baiyangdian Lake Wetland:A Natural or Human Cause? 被引量:9
7
作者 LIU Chunlan XIE Gaodi HUANG Heqing 《Chinese Geographical Science》 SCIE CSCD 2006年第4期314-319,共6页
The shrinking and drying up of wetlands in arid and semiarid areas of China have been widely observed in the recent years,but there has been no consensus on whether the aggravation is caused by human activities or by ... The shrinking and drying up of wetlands in arid and semiarid areas of China have been widely observed in the recent years,but there has been no consensus on whether the aggravation is caused by human activities or by global climate warming.For a better understanding of the cause,this study investigates the dynamic changes of Baiyangdian Lake wetland over the last 40 years.It is shown that since the 1980s,Baiyangdian Lake has suffered from an insufficient water input and shrunk considerably.By using SPSS11.0,this study undertakes a detailed analysis on the significance of the effects of the possible driving factors for the degradation.It is identified that the North China Plain has been warming up significantly in recent years,which causes a significant reduction in the precipitation and inflow to the lake.Although human disturbances such as the irrigation and storage of water in reservoirs do not play a decisive role,they accelerate the degradation and their effects should be minimized. 展开更多
关键词 华北平原 白洋淀 湖泊湿地 面积缩小 干枯 气候变化 人类活动 水文学过程
下载PDF
Application of Participatory Development Theory in Wetland Ecotourism Initiatives——A Case Study of Baiyangdian in Anxin of Hebei Province 被引量:1
8
作者 ZHANG Meng SONG Jinping ZHANG Ning 《湿地科学》 CSCD 2008年第3期422-428,共7页
As one of the few ecological wetlands in North China,Baiyangdian bears multiple important ecological functions,including ①adjusting the ecological balance of North China;②safeguarding the downstream areas,especially... As one of the few ecological wetlands in North China,Baiyangdian bears multiple important ecological functions,including ①adjusting the ecological balance of North China;②safeguarding the downstream areas,especially Tianjin City,the Beijing-Shanghai Railway and Huabei Oil Field;③serving as the reservoir for the North-to-South Water Diversion Project and the emergent use of water for Beijing;④conserving biodiversity.Wetland ecotourism is a scientific and wise use pattern for wetland resources,through which,a source of financing is provided for wetland conservation,economic alternatives are generated for local people to reduce overexploitation on wetland resources and the public awareness of environmental protection is enhanced.Since wetland ecotourism can benefit the co-existence between human and nature and promote social equity between people,it enjoys broad promise for popularization and implementation.The proactive cooperation and sound interaction between main stakeholders,and the wide participation of the community residents,will guarantee the sustainable development of wetland ecotourism.Based on the analysis of current status of participation and interactive relationships of the main stakeholders in Baiyangdian tourism,this article made an attempt to apply the theory of participatory development to the ecotourism initiatives of Baiyangdian wetland,discussed and brought forward the countermeasures to improve community participation in wetland ecotourism under the guidance of this theory. 展开更多
关键词 湿地 旅游资源 旅游业 发展战略 河北
下载PDF
Design and Realization of Baiyangdian Water Environment Information System Based on ArcGIS Engine
9
作者 Fan Li Xiaoyan Li +1 位作者 Hao Xu Shuxuan Liang 《Journal of Environmental Science and Engineering(A)》 2013年第1期15-20,共6页
关键词 水环境信息系统 ArcGIS 设计工作 白洋淀 Engine 水质信息 环境管理 保护生态环境
下载PDF
Comprehensive Study on Degradation and Management of Baiyangdian Lake in North China
10
作者 Yanrui Shang Huilian Shang +2 位作者 Jian Liang Haifeng Shen Gongying Liu 《Journal of Environmental Science and Engineering(B)》 2013年第6期337-342,共6页
关键词 中国北方 白洋淀 管理 保护生物多样性 降解 生态功能 可持续发展 美学价值
下载PDF
Toward to agricultural green development by multi-objective zoning and nitrogen nutrient management:a case study in the Baiyangdian Basin,China
11
作者 Xiaomeng ZHANG Xiangwen FAN +6 位作者 Wenqi MA Zhaohai BAI Jiafa LUO Jing YANG Ling LIU Jianjie ZHANG Lin MA 《Frontiers of Agricultural Science and Engineering》 CSCD 2024年第1期140-154,共15页
Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Op... Although China has achieved great advancements toward national food security,the country is still confronted with a range of challenges,including natural resource stress,imbalanced diets and environmental pollution.Optimized management of crop–livestock systems is the key measure to realize agricultural green transformation.However,optimized management of crop–livestock systems that use multi-objective zoning is lacking.This study employed a multi-objective zoning management approach to comprehensively analyze four indicators:ammonia volatilization,nitrogen surplus,soil carrying capacity and ecological red line area.With its significant ecological integrity and a strong emphasis on sustainability,the Baiyangdian Basin serves as a unique and suitable test case for conducting analyses on multi-objective nutrient optimization management,with the aim to facilitate the agricultural green transformation.This study finds that less than 8%of the area in the Baiyangdian Basin meet the acceptable environmental indicator standard,whereas around 50%of the area that had both nitrogen surplus and ammonia volatilization exceeded the threshold.Implementation of unified management,that is,the same management technique across the study areas,could result in an increase of areas meeting environmental indicator thresholds to 21.1%.This project developed a novel multi-indicator partition optimization method,in which distinct measures are tailored for different areas to satisfy multiple environmental indicators.Implementation of this method,could potentially bring more than 50%area below the threshold,and areas with ammonia emissions and nitrogen surplus could be reduced to 15.8%.The multi-indicators partition optimization method represents a more advanced and efficiency-oriented management approach when compared to unified management.This approach could be regarded as the best available option to help China achieve agricultural transformation to improve efficient production and reduce environmental pollution.It is recommended that current policies aimed at nutrient management toward sustainable agricultural development should shift toward the application of multi-indicators partition optimization. 展开更多
关键词 Agricultural green development baiyangdian Basin environmental emission threshold partition management
原文传递
History,Narrative and Realism:Above Baiyangdian Lake by Guan Renshan
12
作者 WANG Jinsheng 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2023年第2期110-134,共25页
Telling Chinese stories and Chinese experience is an important theme of realist literature in the new era.Chinese writers in the new era face the significant challenge of how to understand the"totality of China&q... Telling Chinese stories and Chinese experience is an important theme of realist literature in the new era.Chinese writers in the new era face the significant challenge of how to understand the"totality of China"and how to construct the totality spirit and aesthetic character of the"Chinese"narrative.Above Baiyangdian Lake by Guan Renshan takes the historical changes that occurred in the typical environment of Baiyangdian New Area as the content of narration,revealing the growth of people and history and its"Chinese"connotation through the story of the growth of"new character"in the new era.The novel depicts the"rediscovery"and rebirth of history and traditions of China in the new era by"telling stories,"and puts them under a profound context of the past and present and in a broad vision of China and foreign countries,thus constructing the overall aesthetics of realism in contemporary China with an epic grand narrative.The novel artistically shows the building and growth process of China in the new era,and demonstrates its leveraging of resourcesand unique connotation.It is a typical text for understanding the relationshipbetween theimage shaping of China in the new era and Chinese realism literature,as well as the connotation,function and form of Chinese realism. 展开更多
关键词 Guan Renshan Above baiyangdian Lake NARRATIVE BILDUNGSROMAN
原文传递
The Benchmark and Model of Literature in the New Era:On Above Baiyangdian Lake
13
作者 ZHOU Xinmina 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2023年第2期135-145,共11页
Above Baiyangdian Lake is a novel set against the backdrop of the great changes in rural China in the new era,revolving around the grand theme of China's contribution to the harmonious development of the world wit... Above Baiyangdian Lake is a novel set against the backdrop of the great changes in rural China in the new era,revolving around the grand theme of China's contribution to the harmonious development of the world with Chinese wisdom and its solutions.The subject of Above Baiyangdian Lake is grand as it involves politics,culture,economy,and many other aspects.Its publication has reversed the narrowing tendency of Chinese novels in terms of themes and subjects.Above Baiyangdian Lake reconstructs historical time for Chinese modernization with its time consciousness based on a historical perspective.Wang Juexin and Qiao Mai shaped by the writer have contributed to the range of Chinese contemporary literary characters as typical images of the new characters of the era.The value of epic masterpieces like Above Baiyangdian Lake should be fully explored and advocated to provide a useful reference for the development of literature in the newera. 展开更多
关键词 Guan Renshan Above baiyangdian Lake grand theme grand subject new characters
原文传递
The Light of Ideals and an Ambitious Regional"Epic" ——On Above Baiyangdian Lake by Guan Renshan
14
作者 LI Hao 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2023年第2期156-163,共8页
Above Baiyangdian Lake is another full-length realistic novel written by Guan Renshan after The Maihe River.In this work,Guan Renshan goes beyond traditional rural writing and artistically narrates the grand landscape... Above Baiyangdian Lake is another full-length realistic novel written by Guan Renshan after The Maihe River.In this work,Guan Renshan goes beyond traditional rural writing and artistically narrates the grand landscape of Baiyangdian New Area and the changes of people's fate during its construction.With Guan's refined and mature narrative techniques,the novel clearly shows his ambition to present a“regional epic.”This paper delves into the fictional text and analyzes the structuring method of Above Baiyangdian Lake from multiple perspectives such as its character shaping with historical correspondence,and narrative structure,skills,and style,aiming to provide an approach to interpret the ideological schema of Above Baiyangdian Lake. 展开更多
关键词 Guan Renshan Above baiyangdian Lake REALISM regional epic
原文传递
Sense of the Scene,Reflexivity,and New Local Writing:On Above Baiyangdian Lake by Guan Renshan
15
作者 GUO Baoliang 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2023年第2期146-155,共10页
Above Baiyangdian Lake is a meticulously crafted novel by Guan Renshan nearing a million words in length.The novel offers a panoramic view of everyday life in Baiyangdian Lake and the development of the Xiong'an N... Above Baiyangdian Lake is a meticulously crafted novel by Guan Renshan nearing a million words in length.The novel offers a panoramic view of everyday life in Baiyangdian Lake and the development of the Xiong'an New Area.The novel exemplifies a genuine sense of the scene by presenting readers with a vivid,authentic depiction of our contemporary life.He employs a narrative structure that overlaps the present with the past,blending tradition and modernity to create a truly magnificent epic.Rather than avoiding the contradictions and darkness inherent to humanity,the novel embraces them and strives to accurately depict their complexity,resulting in a more profound reflection on society.Above Baiyangdian Lake expands and innovates the path of local literature by applying a genuinely realistic approach.It not only surpasses Guan's writing style,but also represents a transcendence of local writing conventions in contemporary literature.It draws upon and elevates the literary tradition of the Hehuadian School,emerging as a notable example of new local writing with distinct regional traits. 展开更多
关键词 Guan Renshan Above baiyangdian Lake sense of the scene REFLEXIVITY new local writing
原文传递
探地雷达在白洋淀湖底地层结构探测中的技术攻关与实践
16
作者 王春辉 田蒲源 +1 位作者 郭淑君 孙晟 《地质通报》 CAS CSCD 北大核心 2024年第4期651-657,共7页
白洋淀湖底地层调查对于白洋淀生态地质调查、湖底生态清淤及湿地生态保护具有非常重要的现实意义。为系统探明白洋淀湖底地层结构,从区域尺度对湖底地层实现完整刻画,为钻探调查提供精确的靶区数据支撑,创新了探地雷达应用范围,采用船... 白洋淀湖底地层调查对于白洋淀生态地质调查、湖底生态清淤及湿地生态保护具有非常重要的现实意义。为系统探明白洋淀湖底地层结构,从区域尺度对湖底地层实现完整刻画,为钻探调查提供精确的靶区数据支撑,创新了探地雷达应用范围,采用船载方式,透过水体开展了湖底地层勘查。剖析白洋淀湖底结构探地雷达勘探技术难点,分析了含底泥和不含底泥2种情形下水上勘探电磁波的传播特征和湖底原生地层的地球物理响应条件,建立了淀水+淤泥层+湖底原生地层的湖底简化结构模型。通过对比国内外主流探地雷达系统不同硬件设备的勘探能力与适应条件,优选出双皮划艇搭载50 MHz低频组合天线的工作模式,结合适用于水下电磁波弱信号提取的数据处理技术,获得了白洋淀湖底15 m深度范围的地层结构数据。结果表明,此种工作模式适用于湖区水深小于5 m的水域,原生地层电磁波整体呈现弱反射特征,湖底15 m深度范围内存在2~3组砂层反射界面。淤泥层会大大削弱湖底原生地层的电磁波反射强度。存在厚砂层的水域,电磁波会形成强反射波组,砂层展布形态刻画清晰,砂层厚度变化在0~3 m之间。本项研究实现了湖底地层结构建模分析、天线勘探模式优选、数据处理过程优化等技术集成。该技术成果为白洋淀淀区地下水与地表水三维地质建模提供了基础依据,为湖底地层钻探勘查提供了靶区支撑,有力推动了白洋淀湿地水-陆一体化探测技术方法体系的构建。 展开更多
关键词 白洋淀 水上探地雷达技术 勘探深度 淤泥层 湖底砂层
下载PDF
“三水”统筹的流域水生态环境分区管控技术与实践
17
作者 杨洋 汪自书 +3 位作者 吕春英 靳明 谢丹 刘毅 《环境影响评价》 2024年第3期21-28,共8页
基于“三水”(水生态、水环境、水资源)统筹,开展流域空间精细化管控对推进新时代流域协同保护与治理具有重要意义。按照“‘三水’问题识别—‘三水’分区划定—质量目标确定—管控单元集成”的思路,构建了流域水生态环境分区管控技术... 基于“三水”(水生态、水环境、水资源)统筹,开展流域空间精细化管控对推进新时代流域协同保护与治理具有重要意义。按照“‘三水’问题识别—‘三水’分区划定—质量目标确定—管控单元集成”的思路,构建了流域水生态环境分区管控技术方法。以白洋淀流域为实践对象,识别出流域性突出生态环境问题;衔接现有水生态环境管理分区与政策要求,划定生态保护红线、环境质量底线及资源利用上线;明确“三水”分区域差异化生态环境管理目标与资源环境承载约束,聚类叠“三水”分区并综合划定水生态环境综合管控单元、制定结构化生态环境准入清单。 展开更多
关键词 “三水”统筹 生态环境分区管控 环境质量底线 白洋淀流域
下载PDF
燕赵文脉谱系中的白洋淀作家群
18
作者 刘勇 陈蓉玥 《河北大学学报(哲学社会科学版)》 2024年第2期37-45,共9页
“白洋淀作家群”是生长在河北大地上,继承了燕赵文脉传统,并不断涌动向前吸收时代新质的一个文学团体,他们的创作是燕赵文化在现当代的余响,是河北古老历史底蕴的现代演绎。考察白洋淀作家群发生发展、文学作品和文化生态,在河北文学... “白洋淀作家群”是生长在河北大地上,继承了燕赵文脉传统,并不断涌动向前吸收时代新质的一个文学团体,他们的创作是燕赵文化在现当代的余响,是河北古老历史底蕴的现代演绎。考察白洋淀作家群发生发展、文学作品和文化生态,在河北文学的精神谱系中寻找白洋淀文学的历史定位,有助于更为全面地理解冀中平原的时代变革与文化记忆,从而为河北孕育独特的现代文化品格提供文学支撑,推动京津冀三地“瓣瓣不同,却瓣瓣同心”的协同发展。 展开更多
关键词 燕赵文脉 白洋淀作家群 京津冀协同发展
下载PDF
Distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface water and sediments from Baiyangdian Lake in North China 被引量:45
19
作者 Guohua Dai Xinhui Liu Gang Liang Xu Han Liu Shi Dengmiao Cheng Wenwen Gong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第10期1640-1649,共10页
Persistent organochlorine compounds, including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs) were analyzed in surface water and sediments from Balyan... Persistent organochlorine compounds, including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs) were analyzed in surface water and sediments from Balyangdian Lake, North China. Total concentrations of HCHs, DDTs and PCBs in surface water were in the range of 3.13-10.60, 4.05-20.59 and 19.46-131.62 ng/L, respectively, and total concentrations of HCHs, DDTs and PCBs in sediments were 1.75-5.70, 0.91-6.48 and 5.96-29.61 ng/g dry weight, respectively. Among the groups of HCHs (sum of α-HCH, β-HCH, y-HCH and 6-HCH) and DDTs (sum of DDT, DDD and DDE), the predominance of β-HCH, DDE and DDD in water and sediment samples was clearly observed. This observation suggested that β-HCH was resistant to biodegradation and the DDTs had been transformed to its metabolites, DDE and DDD. For PCBs, penta-, hexa- and hepta-chlorinated congeners were the most abundant compounds in the both phases. Furthermore, the partitioning of chlorinated compounds between sediment and water was investigated to understand their transport and fates in aquatic ecosystems. The results indicated that average logs of organic carbon-normalized sediment-water partition coefficients (logK∝) for OCPs varied between 3.20 and 5.53, and for PCBs, logK∝ values ranged from 3.19 to 5.57. The observed logK∝ was lower than their equilibrium logK∝ predicted from linear model, which may be attributed to the solubility enhancement effect of colloidal matter in water phase and the disequilibrium between sediment and water. 展开更多
关键词 oranochlorine pesticides polychlorinated biphenyls water sediment baiyangdian Lake North China
原文传递
基于GEE的白洋淀水体生态补水后时空格局变化分析
20
作者 阳星 王世岩 +5 位作者 韩祯 李步东 王亮 汪洁 孙龙 巴艺博 《中国农村水利水电》 北大核心 2024年第4期122-131,140,共11页
生态补水是白洋淀生态环境治理的一项重要举措,根据生态补水机制的变化过程,将白洋淀的生态补水过程分为临时补水阶段、应急补水阶段和稳定补水阶段。为进行各生态补水阶段下白洋淀水体的时空格局变化分析,通过GEE对白洋淀在1990-2022年... 生态补水是白洋淀生态环境治理的一项重要举措,根据生态补水机制的变化过程,将白洋淀的生态补水过程分为临时补水阶段、应急补水阶段和稳定补水阶段。为进行各生态补水阶段下白洋淀水体的时空格局变化分析,通过GEE对白洋淀在1990-2022年的701幅遥感影像进行水体和冰体提取,分析不同阶段下水体时空变化格局,以及专门分析了冬季结冰期的冰体面积变化。主要得出以下结论:①在各个生态补水阶段,白洋淀水体面积均呈现在夏季最小,冬春季最大的特点,而随着生态补水机制的不断完善,白洋淀水体面积变化幅度逐渐减小,呈现“削峰补低”的变化规律,其中临时补水阶段的逐月平均水体面积介于0.63~186.03 km^(2),稳定补水阶段的逐月平均水体面积介于17.88~109.15 km^(2),变化幅度减小了50.77%;②生态补水机制的完善让白洋淀呈现永久性水体大幅增加,间歇性水体大幅减小的变化规律,其中临时补水阶段永久性水体面积为7.66 km^(2),而稳定补水阶段的永久性水体面积为23.62 km^(2),增加了208.16%,间歇性水体面积则从263.50 km^(2)减少到143.58 km^(2),减小了45.51%;③从冰体面积变化角度分析,随着生态补水机制的不断完善,白洋淀的冰体面积不断减小,其中一月份的平均冰体面积从72.77 km^(2)减小到12.60 km^(2),减小了82.69%。结果表明:生态补水机制的完善并没有导致白洋淀水体面积不断增加,而是使白洋淀的水体环境更加破碎化;在全球变暖以及其他因素的影响下,白洋淀的冰体面积大幅减小;这种趋于破碎化、板块化的水域特征可能不利于生物多样性的保护,但鉴于生态系统对于水文响应具有滞后性,今后需进一步加强生态水文响应过程监测和研究。 展开更多
关键词 白洋淀 GEE 生态补水 水体提取 冰体提取 时空变化
下载PDF
上一页 1 2 38 下一页 到第
使用帮助 返回顶部