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1.
中国生态环境敏感性及其区域差异规律研究   总被引:154,自引:17,他引:154       下载免费PDF全文
我国日益恶化的生态环境越来越引起社会各界的关注,如何对生态环境问题采取有效的综合整治策略,已经成为科学界面的一个挑战,本研究首先综述了我国主要生态环境问题-水土流失、沙漠化、盐渍化和酸雨的空间分布格局和空间相关性,提出了生态敏感性的概念,分析了影响我国主要生态环境问题敏感性的因素,特别是气候对生态环境敏感性的影响,综合地提出了中国生态环境敏感性化区,并探讨了各分区的特点。  相似文献   

2.
为了解和加深盐生植物资源在植物盐方面的发展程度,采用文献计量方法、可视化网络分析、内容分析法对中国知网搜集的2021年6月30日前的植物盐专利数据进行分析,从专利的发文量、专利发明人、专利申请人、专利主题了解植物盐领域的研究情况,结果表明:植物盐专利的年发文量呈现先增加后减少的趋势;前期以独立发明人为主,近几年开始有合...  相似文献   

3.
【目的】通过研究文献了解我国昆虫资源学的研究现状和发展趋势。【方法】基于中国知网(CNKI)和WebofScience两个在线数据库,检索有关昆虫资源研究的文献。利用文献题录信息统计分析工具SATI 3.2、Ucinet 6.671、NetDraw 2.166等对所获得的数据进行分析,从文献计量的角度揭示我国昆虫资源学的发展现状。【结果】检出文献的主体发表单位都是大学。研究热点集中于食用昆虫和药用昆虫的开发利用,蝗虫、家蝇、黄粉虫、紫胶虫、蚂蚁等种类提到较多,研究内容侧重于分类、活性物质如蛋白质和壳聚糖等的开发。【结论】昆虫资源是宝贵的生物资源,我国许多学者正在从事昆虫资源的研究与利用,但研究水平仍有较大的提升空间,研究投入也有待加强。  相似文献   

4.
从文献计量角度分析中国生物多样性研究现状   总被引:1,自引:1,他引:1       下载免费PDF全文
刘爱原  郭玉清  李世颖  林茂  王春光 《生态学报》2012,32(24):7635-7643
以汤森路透科技集团的WEB OF KNOWLEDGE信息平台提供的Science Citation Index Expanded数据库为数据源,检索到从1997年至2009年期间国际生物多样性研究论文文献219773篇,其中11182篇来自于中国学者。利用NoteExpress软件,对这13a间生物多样性研究论文发表的国家分布、年度分布、研究机构、引用情况、期刊分布和学科分类等做的分析与比较表明:1)全球生物多样性研究的论文数量一直呈增长趋势,中国13年间每年发文量占当年全球生物多样性论文总量的百分率逐年增加;2)从论文总被引频次、篇均引用次数和h-index三项论文影响力特征参数分析,中国与国际其他国家相比有一定差距;3)从学科分类来看,与国际相比,中国在生物多样性保护领域、进化生物学和海洋与淡水生物学领域研究略显不足,昆虫学和真菌学研究领域活跃。  相似文献   

5.
为了解国内碱蓬的研究现状和未来发展趋势,采用文献计量方法,借助中国知网数据库,以"碱蓬"为主题,检索1999~2019年间发表的关于碱蓬研究文献、专利及成果.从发文量、主要发文机构、作者、主要期刊、被引频次、专利、成果等方面对碱蓬相关研究进行分析,探讨碱蓬研究领域的概况.结果表明:碱蓬领域的总发文量从整体上呈先增加后平...  相似文献   

6.
我国地表臭氧生态环境效应研究进展   总被引:18,自引:1,他引:18       下载免费PDF全文
针对当前我国大部分地区夏季出现的高浓度地表臭氧污染,综述了目前在地表臭氧的生态环境效应方面取得的研究进展及未来的研究展望。主要进展包括地表臭氧的污染水平,及其对植物的影响机制,具体包括地表臭氧对植物叶片的表观伤害、光合固碳能力、植物源挥发性有机化合物(BVOCs)释放、土壤微生物和土壤温室气体排放等方面的影响;在此基础上,提出了减少臭氧生态环境效应的管理措施。此外,对我国未来的研究进行了展望,建议加强在农田和森林布设臭氧浓度监测点、开展多因子同时存在的交互作用、气孔臭氧吸收量-响应(生物量或产量)关系以及臭氧对地下生态过程累积效应的长期定位等方面的研究,以期为我国地表臭氧污染的生态环境效应研究起到一定的推动作用。  相似文献   

7.
荆延德  樊蕊 《生态学报》2018,38(11):4077-4087
以中国知网学术期刊网络出版总库(CNKI)和WEB OF SCIENCE(WOS)中1986—2016年的期刊论文为数据源,以非点源污染或面源污染(non-point pollution or Diffused pollution or non-point source pollution)和模型(Model)为主题进行检索,共检索到国内文献1474篇和国外文献1046篇。利用共词分析方法,同时结合CiteSpace、SPSS和Bibexcel软件对检索结果进行分析,利用Ucinet和NetDraw软件绘制出共词网络可视图,依据处理后的结果对非点源污染模型的研究趋势进行系统的梳理分析,从多个角度对非点源污染模型的研究现状与发展情况进行分析,包括发表文章的关键词、年代分布、发表期刊、著者、高被引文章等,在此基础上分析出国内外在非点源污染模型领域中的研究概况及研究热点,明确非点源污染模型研究的探索方向,为以后非点源污染模型的研究提供理论依据。  相似文献   

8.
为揭示我国三叶虫研究的发展脉络, 本文使用CiteSpace引文可视化分析软件对收录在中国知网、《中文科技期刊数据库》以及Web of Science核心合集数据库中的相关文献计量并进行知识图谱分析。目前我国三叶虫研究正处于逐步攀升的发展态势, 研究机构合作网络紧密, 国际影响力逐步提升。我国三叶虫研究热点区域为扬子板块的贵州、云南、湖南、湖北、安徽以及华北板块的河北、山东, 研究热点地层为寒武系与奥陶系; 中文文献研究内容主要聚焦于生物地层学、形态学与分类学, 英文文献研究内容主要聚焦个体发育和生物地层学研究; 研究手段丰富, 跨学科特征显著, 包括地球化学、生态学、流体力学等; 前沿研究课题聚焦于“个体发育蜕壳研究”“高精度三叶虫生物地层框架”“三叶虫多样性与宏演化”等子域, 结合Micro-CT等新技术方法。从论文发表量上看, 我国三叶虫研究经历了初步发展期(1965年前)、停滞期(1966—1975年)、快速上升期(1976—1986年)、波动缓增期(1987—2023年)四个阶段。目前, 该研究方向仍具有巨大的发展潜力。  相似文献   

9.
作为一门交叉学科,纳米生物学成为当前生命科学研究在纳米尺度上的前沿与热点.本文从文献计量学的视角,分析了近年来纳米生物学领域的论文发表数量和被引用情况,重点关注了纳米生物医学、纳米生物材料、纳米生物化学和纳米生物物理4个主要分支领域的基本情况和研究主题,呈现了纳米生物学可视化的知识图谱;并结合战略研讨和专家研判,凝练获...  相似文献   

10.
森林火灾是大气中气体污染物和颗粒物的重要来源,可对全球气候系统、大气环境以及生态系统产生重要影响,对全球温室气体和含碳颗粒物释放具有重要的贡献,是推动全球气候变化的重要因素。森林火灾释放污染物已成为区域乃至全球范围内重要污染源之一,这些污染物质与辐射、能见度以及温室效应等问题直接相关。准确地描述森林火灾释放的气体和颗粒污染物释放机理、释放总量、时空分布特征、不同尺度的扩散过程模拟,以及对区域大气环境的影响,对于量化森林火灾释放污染物总量及区域影响具有重要意义。基于森林火灾污染物质释放方面的国内外文献,从火灾释放的污染物质对环境的影响、森林火灾释放污染物定量化和传输路径监测的研究方法、污染物质的扩散和运输模型以及跨区域影响等几个方面进行了综述。森林火灾释放的CO、PM10和PM2.5对环境和人的生命安全造成巨大威胁,而且森林火灾释放的污染物质能够随气流长距离传输,不仅对当地的空气造成污染,污染物也能够随着气团进行长距离传输,并在传输过程与当地气溶胶混合,形成跨区域污染。森林火灾释放污染物扩散、传输模拟通过不同模型相互耦合完成,包括可燃物载量估算模型、可燃物消耗和释放模型、污染物扩散传输模型,以及污染物预测和可视化模型等。总结了国内外森林火灾释放污染物质主要研究方法,并展望了今后研究重点:目前我国关于森林火灾释放物质相关的研究尚不足以支撑我国森林火灾温室气体释放、污染物释放等方面的研究,并且我国目前还没有发展出适合于我国的森林火灾污染物释放模型,以及污染物扩散、传输系统。森林火灾排放因子库大多数引用国外研究结果,在一定程度上增加不确定性,缺乏森林火灾对区域大气环境影响的定量化研究。因此,今后我国应加强对森林火灾污染物质释放与影响的研究,尤其是污染物质扩散和传输模型的预测和可视化研究以及排放因子的测量。  相似文献   

11.
12.
Coastal wetlands are facing an increasingly high risk of degradation and loss due to a wide variety of human activities and natural processes. Human encroachment, including land reclamation, drainage, and introduction of invasive species, has direct negative effects on wetlands, mainly through changes in hydrology and vegetation. Additionally, accelerated sea level rise (SLR) can result in flooding of wetlands in low-lying coastal zones. In this study, we present a rapid risk assessment method for coastal wetland loss and degradation. The main stress factors, i.e., urban sprawl, agriculture, coastal erosion, and SLR, have been examined and quantified through remote sensing and geographic information system spatial analysis. A weighted factor-based linear model has been used to evaluate the spatial risk levels of wetland loss. The proposed methodology is applied to the low-lying coastal wetlands of Hangzhou Bay in Shanghai, China. The results show that the regions closer to the sea have relatively higher risk levels on the landward side of the coastline, but relatively low risk levels on the seaward side of the coastline. This work emphasizes the need to sustainably use and protect wetlands in order to reduce disaster risks and contribute to the improvement of human well-being.  相似文献   

13.
Chua Thia-Eng 《Hydrobiologia》1997,352(1-3):159-166
Coastal environmental management requires timely and appropriate policy, management and technological interventions to address a host of interrelated environmental problems arising from unplanned and unregulated coastal developments. These interventions can only be effective if they are based on sound scientific (including socioeconomic) information. Thus, science plays a significant role in the environmental management of coastal and marine areas. This paper highlights the essential components of environmental coastal management that require scientific interventions, particularly in providing the scientific basis for policy interventions, and preventive and/or mitigating measures. The integration and packaging of scientific information for management actions require an interdisciplinary effort to address identified management problems. Scientific research should respond to management needs and make contributions to the better understanding of ecosystems and their responses to human interventions. Scientific information urgently required for management includes an understanding of interactions in coastal resource systems, identification, evaluation and prioritization of management issues, management strategies and actions, and development of methodologies and tools for environmental management. Obstacles to management-oriented research have also been identified to include defective perception among scientists, defective communication between scientists and decision makers, intellectual and cultural arrogance, and inadequate technical and management capability at the local level. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

14.
Abstract

Atmospheric particulate samples were collected during three typhoons in 2006 (Chanchu, Bilis, and Kaemi) from Dongshan and Pingtan Islands along the coastal areas of Fujian Province and were analyzed for organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). The observations were divided into three periods, namely, pre-typhoon, typhoon, and post-typhoon, to analyze the variations in POP concentrations. The results showed that the PCB and OCP concentrations had daily variations during the pre-typhoon period, while different variation trends were observed during the typhoon periods. The concentrations of those contaminants increased dramatically during typhoon Chanchu (the total concentrations of PCBs and OCPs increased 25 and 24 times, respectively), whereas those values decreased slightly during the typhoon Bilis and Kaemi. However, POPs levels all decreased noticeably during the three post-typhoon periods due to heavy rainfall caused by the typhoons. Observations of an ensemble of factors, including the typhoon migration routes, landfall season, air mass origins and meteorological conditions, and the typhoon migration route was the dominant factor to cause high levels of POPs during the typhoon Chanchu period. Toxicity assessment indicated that the effect of PCB and OCP during the typhoon period should be a concern, which could pose a high potential health risk to organisms.  相似文献   

15.
利用红树植物监测海岸油污染方法初探   总被引:3,自引:0,他引:3  
卢昌义  林鹏 《生态学杂志》1990,9(1):57-59,66
一、前言在海洋污染物中,石油污染是最普遍和最严重的一种。这种污染主要来自海上油船运输泄漏、海洋油田开发、油层自然渗出造成的远洋石油污染。近年来,随着沿海各地拆船工业的迅速发展,由于忽视环保工作或环保措施跟不上生产发展,拆船作业中大量含油压仓水排入海中,以及船只轮机部位大量存油,油垢溢  相似文献   

16.
Two-thirds of the coastal rivers and bays in the United States are degraded from nutrient pollution, and nitrogen inputs these waters continue to increase. The nitrogen comes from a variety of sources, including runoff from agricultural fields, concentrated animal feeding operations, atmospheric deposition from fossil fuel combustion, and sewage and septic wastes. Technical solutions for nitrogen pollution exist at reasonable cost. That most of these solutions have not yet been implemented to any significant extent across the United States suggests that new policy approaches are necessary. The best solution may involve a combination of voluntary and mandatory approaches, applying different approaches to different sources of nitrogen pollution. A watershed-based approach that relies heavily on voluntary mechanisms (such as crop-yield insurance to reduce over-fertilization) is likely to be the most effective for some sources of nitrogen (such as runoff from agricultural fields), while a uniform national regulatory approach may be better for others (such as NOx emissions from fossil fuel combustion). Implementation of management strategies should be carefully coupled to monitoring programs to assess the effectiveness of these strategies. While both nitrogen and phosphorus are important to control, the focus should be on nitrogen management, in part because nitrogen is more generally the causal agent of coastal eutrophication. Also, while nitrogen-control practices tend to also reduce phosphorus pollution, phosphorus-control practices often have little effect on nitrogen. Although current scientific and technical knowledge is sufficient to begin to make substantial progress toward solving coastal nitrogen pollution, progress will be made more quickly and more cost effectively with increased investment in appropriate scientific research.  相似文献   

17.
王晓利  侯西勇 《生态学报》2017,37(21):7098-7113
基于1961-2014年156个地面气象站日尺度的气温数据集,利用趋势分析、小波分析、Mann-Kendall检验、累积距平、Pettitt检验、主成分分析等方法分析了中国沿海地区极端气温事件的时空变化特征。结果表明:中国沿海及各子区域极端气温暖指数呈上升趋势,冷指数和气温日较差呈下降趋势,夜指数的年际倾向率明显大于昼指数的年际倾向率;除相对指数、极高值指数和冷(暖)持续日数的多年均值在各子区域之间相差不大以外,霜冻日数、冰冻日数以及气温日较差的多年均值从北至南依次递减,与之相反,夏季日数、热夜日数、极端气温极低值指数以及生长季长度的多年均值则从北至南依次增加。各子区域极端气温指数年际间的主周期介于2-8 a,均无显著的年代际震荡周期;各子区域极端气温指数的突变主要发生在1980s和1990s期间,冷指数和极低值指数的突变时间稍早于暖指数和极高值指数的突变时间,突变后,极端暖事件和气温的极值事件进入多发阶段,极端冷事件进入相对少发的阶段;主成分分析中第一主成分高载荷的极端气温指数对日均气温和日最高(低)气温均有较好的指示性,这类极端指数两两之间的相关性也较强,低载荷的极端气温指数对日均气温和日最高(低)气温的指示性相对较弱,与其他极端气温指数之间的相关性也均较弱。  相似文献   

18.
闽东沿海防护林台风灾害的影响因子   总被引:7,自引:0,他引:7  
以2010年台风"鲇鱼"(编号1013)为例,调查闽东主要海防林树种台风受灾情况,并对其影响因子进行分析,结果表明:1)不同树种受害程度差异明显,阔叶树种受害重于针叶树种,平均受害级和受害指数分别高出79.1%和76.7%。其中,桉树受灾最重,平均受害级和受害指数分别比湿地松、木麻黄高出90.5%、36.2%和86.7%、36.6%。受灾类型中,折干现象最严重,比例高达40.7%。2)林木不同形态特征受灾程度差异显著,折干类型集中于12~14cm径级,比例为56.8%,倒伏、掘根类型集中10~12cm,比例为57.9%,弯干、断稍现象径级分布较均匀,但同在14cm比例最高,分别为28.6%和18.3%。林木抗风性能与植株尖削度成正相关,而与树高、树冠面积、树冠相对高度成负相关。3)地形条件是影响林木受灾的重要因素,表现为受灾程度迎风坡大于背风坡,陡坡大于缓坡,同一坡向上,迎风坡下腹大于上腹,背风坡正好相反。4)割脂对湿地松抗风性能有较大影响,割脂林木受害指数比未割脂高40.6%,因割脂发生折干植株比例为92.7%。  相似文献   

19.
Anthropogenic activities on coastal watersheds increase nutrient concentrations of groundwater. As groundwater travels downslope it transports these nutrients toward the adjoining coastal water. The resulting nutrient loading rates can be significant because nutrient concentrations in coastal groundwaters may be several orders of magnitude greater than those of receiving coastal waters. Groundwater-borne nutrients are most subject to active biogeochemical transformations as they course through the upper 1 m or so of bottom sediments. There conditions favor anaerobic processes such as denitrification, as well as other mechanisms that either sequester or release nutrients. The relative importance of advective vs. regenerative pathways of nutrient supply may result in widely different rates of release of nutrients from sediments. The relative activity of denitrifiers also may alter the ratio of N to P released to overlying waters, and hence affect which nutrient limits growth of producers. The consequences of nutrient (particularly nitrate) loading include somewhat elevated nutrient concentrations in the watercolumn, increased growth of macroalgae and phytoplankton, reduction of seagrass beds, and reductions of the associated fauna. The decline in animals occurs because of habitat changes and because of the increased frequency of anoxic events prompted by the characteristically high respiration rates found in enriched waters.  相似文献   

20.
There are two major potential effects of rising atmospheric temperature on freshwater wetlands: direct effects, and indirect effects of rising sea level. Direct effects are varied, but muted by the high specific heat of water and the key dependence of freshwater production on nutrients rather than temperature. However, there may be effects on lake stratification, fish distribution and restoration of lakes by biomanipulation. Rising sea levels have the potential to alter lowland riverine lakes very considerably by saline influx. A holistic, intuitive view is more likely to produce realistic scenarios for the future than one based on reductionism.  相似文献   

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