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1.
分析了中国部分自然保护区面积与生物物种(动物和植物)之间的关系;其次讨论了动物与植物以及动物与动物物种数量间的关系.结果表明,我国部分自然保护区的面积多数偏小,鸟类、哺乳类、种子植物、爬行类、昆虫和两栖类等与其面积的相关关系依次减弱;其植物种数与鸟类种数的作用影响最大、关系最密切;两栖类与各类动物之间以及鸟类与各类动物之间的物种数目呈显著的相关关系;两栖类与昆虫类为负作用影响;鸟类与两栖类和爬行类以及哺乳类与两栖类为最大的正作用影响.  相似文献   

2.
The assessment of the ecosystem health of urban rivers and lakes is the scientific basis for their management and ecological restoration. This study developed a three-level indicator system for its assessment. The results indicated that: Zhonghai and Nanhai are in the state of transition from unhealthy to critical state and all the other lakes are in unhealthy states. Water environmental quality, structure and function of the aquatic ecosystem, and the structure of waterfront areas were the constraints. Nanhai was ranked as poor and the others were all ranked as very poor. However, the ecological environment of Zhonghai and Nanhai were better than the others, the sums of the degree of membership to the healthy state and critical state were all close to 0.6. and the restorations of these lakes were moderate. The sums of the degree of membership to the healthy state and critical state of the other lakes were under 0.3, as it was difficult to restore these lakes. Some suggestions on scientific management and ecological restoration of the six lakes were proposed: $`To control non-point pollution and to improve the water quality of six lakes and the water entering into these lakes; $aTo improve the hydrological conditions of six lakes; $bTo rehabilitate the aquatic ecosystem and waterfront areas.  相似文献   

3.
The global change currently observed is deemed to generate accelerated coastal erosion and an increase in frequency and intensity of extreme weather events. Populated tropical island coasts are particularly vulnerable. Awareness of this vulnerability has prompted recourse to the construction of operational observatories on the coastal dynamics of several French tropical islands, including Mayotte. The aims of this initiative are to characterise the coastal morphology of tropical islands and to monitor their rhythms and mechanisms of evolution, adaptation and resilience in the face of extreme climate and wave events (cyclones, storms, surges, strong swells…). Based on this, appropriate defence and/or adaptation strategies can be developed and implemented. Mayotte Island is a fine example of the implementation and utility of such an observatory. The island, in the southwest Indian Ocean, is characterised by a highly diversified coral reef-lagoon complex comprising pocket beaches and mangroves subject to increasing pressure from strong island demographic growth. The operational observatory set up on the island incorporates a Geographical Information System (GIS) based on a network sourced by various field measurements and observations conducted on the coastal forms on the basis of a predefined protocol and methodology. Field experiments include hydrodynamic measurements, topographic surveys, and observations, and these are coupled with the analysis of aerial photographs and regional meteorological data in order to gain a better understanding of the coastal morphology and of the evolution of the reef-lagoon complex. The results fed into the observatory and analysed through the GIS provide interactive maps of the coastal landforms and their evolution and dynamics over various timescales. Within a local framework of strong socio-economic and demographic pressures, and a more global context of environmental change, this observatory should lead to a better understanding and prediction of the morphodynamics of the coast of Mayotte, while providing data to the public at large, to researchers, and to stakeholders involved in decision-making in the face of the major and rapid environmental and socio-economic changes liable to affect the fragile reef-mangrove systems and pocket beaches.  相似文献   

4.
本文聚焦我国水生态保护与修复工作,结合长期实践,分析当前的形势和任务,指出了当前要着力解决的水生态问题主要是:在大坝上游,河流变湖库,生境变化导致生物物种变化;水库水流流速变缓,水体自净能力降低,导致富营养化及藻类水华。在大坝下游,清水下泄,冲刷下游河道导致局部河道河势变化较大;水库蓄水使坝下游春季水温下降、秋季水温升高,水温变化过程滞后;水库蓄水导致大坝下游的水文过程改变,水的流量、流速、流态发生变化。在河道(航道)整治工程中,裁弯取直,缩短水流在河道中的停留时间,河岸衬砌和硬化,减少水向沿河堤岸的渗透,在大降水和洪水时易造成涝灾和洪灾。在涉湖工程中,阻隔河湖,填湖造地。在明确存在问题和迫切需求的基础上,提出了切实可行的对策建议。当前水生态保护与修复要围绕一条主线,即"人要发展,鱼要生存"的"人鱼线",要采取"调、控、退、通、改、拆"的综合措施,即生态调度,控制水污染,退建还水、退田还湖,河湖连通,对已建涉水工程进行生态化改造,对在保护区、重点风景名胜区、特有鱼类栖息地修建的小型工程要采取坚决措施拆除,恢复原貌。  相似文献   

5.
华北平原夏玉米季化肥氮去向及土壤氮库盈亏定量化探索   总被引:2,自引:0,他引:2  
为提高华北平原夏玉米种植体系的氮肥利用率、减少氮肥对环境的污染,对前人的15N示踪试验数据进行整理核算,分析肥料氮、作物氮、土壤氮三者之间的关系,探明夏玉米季化肥氮的去向及土壤氮库的盈亏情况。结果表明:华北平原地区玉米产量最高时施氮量平均为190 kg·hm-2;秸杆吸氮量高于籽粒,且吸氮量随施氮量增加而升高,土壤残留量和损失量有随施氮量增加而增加的趋势;土壤氮库盈亏量与施氮量之间呈现线性极显著正相关,在秸秆50%和100%还田的两种条件下,施氮量为198 kg·hm-2和137 kg·hm-2时,土壤氮库达到平衡;推荐施氮条件下夏玉米对氮肥的吸收利用率远高于传统施氮,过量施氮会引起作物产量和氮肥利用率降低的负效应,增加土壤氮素残留和损失;施氮量在40~360 kg·hm-2范围内时,3种秸秆处理方式下,氮肥各去向绝对量与施氮量之间均呈显著线性相关关系;而氮肥各去向比率与施氮量之间只有地上部吸收率和籽粒吸收率与施氮量之间呈显著线性相关关系。由此,明确了华北平原夏玉米合理施氮量:秸秆50%还田时,为198 kg·hm-2;秸秆100%还田时,为137 kg·hm-2,揭示了华北平原夏玉米施氮量与土壤氮库盈亏量呈线性极显著正相关。这为确定华北平原夏玉米合理施氮量,提高氮肥利用率,避免肥料浪费及其对环境的危害提供了理论依据。  相似文献   

6.
Analysis of the evolution, distribution and ecology of marine prosobranchs of the genera Neptunea and Littorina and amphipods of the genera Anisogammarus and Gammarus demonstrates the possibilities of ecological and palacoecological methods in composing evolutionary reconstructions. A comparative study of historical climate changes and of palaeogeography in areas inhabited by certain taxonomic groups, coupled with information on the distribution and ecology of species belonging to these groups, allows us to determine the time and locality of the origin of diverse biogeographical groups of species and to trace the routes of their further distribution, even in those organisms which have no fossil remains. Species dwelling under conditions which correspond historically to the most ancient climate of their dwelling area prove to be more primitive than species dwelling under newly-formed climatic conditions. For instance, subtropical species of the genera under consideration, in the Northwestern parts of the Pacific and Atlantic Oceans, have proved to be more ancient and primitive than species inhabiting the upper boreal Pacific and Atlantic waters and the Arctic Ocean. Therefore, the palaeoecological analysis of the historical development of faunas from different regions of the globe, combined with the application of the morphological principle, can significantly contribute to a more detailed and precise understanding of the processes and trends of evolution which compose the phylogenetic schemes of the taxonomic groups under discussion.  相似文献   

7.
为了解不同浓度铜(Cu)、锌(Zn)重金属污染土壤对乔木抗氧化指标的影响以及为植物修复蠡河重金属污染岸带提供理论依据,选取广玉兰(Magnoliagrandiflora)、香樟(Cinnamomumcamphora)、榉树(Zelkovaschneideriana)幼苗,采用土培法浇灌重金属溶液模拟土壤污染环境,研究不同浓度重金属Cu/Zn对乔木脯氨酸含量、过氧化物酶活性、过氧化氢酶活性及丙二醛含量的单一及复合影响。实验表明,单一Cu胁迫对广玉兰、香樟和榉树的毒害作用较单一,Zn胁迫严重;Cu/Zn复合作用下,3种乔木抗氧化指标均在Cu15和Zn110时达到最大值,表现出较强的抗性,而后随着复合作用强度增加,重金属对其毒害作用增大;75μg/gCu和210μg/gZn单一及复合胁迫时,广玉兰丙二醛含量相对香樟和榉树较接近对照值,过氧化物酶和过氧化氢酶活性较大,脯氨酸含量差别不大。综合分析,不同乔木在不同浓度重金属胁迫下抗氧化指标作出不同响应,广玉兰对高浓度Cu/Zn胁迫不敏感,承受能力和抗性较强,适合于修复Cu/Zn污染较严重土壤。  相似文献   

8.
沈丹 《生态环境》2003,12(3):346-348
江南地域在我国虽属水资源相对充足的地区,但水生态建设不容忽视。文章针对江南传统村镇中河道水网的水生态处理及院落村舍的给排水处理两方面,在认同原始功能的合理性的基础上分析现当代的改建对于水环境自我调节的影响后果,讨论了在原有基础上进行水环境改造更新的可行性,并探讨结合Reduce(减少)、Reuse(回用)、Recycle(循环)的3R原则进行设计的方法和发展前景。  相似文献   

9.
Analysis of the structure and function of urban metabolic systems is an important goal of urban research. We used network pathways and network utility analysis to analyze the basic network structure of the urban metabolic system and the complex ecological relationships within the system, providing a new way to perform such research. Using four Chinese cities as examples, we developed an ecological network model of the urban metabolic system. By using network pathway analysis, we studied the changing relationships between metabolic length and the number of metabolic pathways, and between metabolic length and reachability. Based on the distribution of the number of metabolic pathways, we describe the basic structure and intercompartment relationships of the system. By using the sign distribution in the network utility matrix, we determined the ecological relationships and degree of mutualism between the compartments of the system. The basic components of the system consisted of the internal environment, the external environment, and the agricultural, industrial, and domestic sectors. With increasing metabolic length, the ecological relationships among the components of the system became more diverse, and the numbers of metabolic paths and their reachability improved. Although the basic network structure of the four cities was identical, the mutualism index differed. Beijing's mutualism index was superior to that of Shanghai, and much higher than those of Tianjin and Chongqing. By analyzing the structure and function of the urban metabolic system, we provide suggestions for optimizing the structure and adjusting the relationships, and propose methods for the application of ecological network analysis in future urban system research.  相似文献   

10.
从1997年开始,对荔枝叶片和土壤常量有效养分质量分数、pH值的年周期变化进行了研究。通过统计学分析,初步探明叶片各元素质量分数季节性变化的模式及其特点,以及土壤有效养分质量分数、pH值年周期变化的趋势;分析了年周期变化中叶片与土壤分析值之间的相关性。  相似文献   

11.
太湖蓝藻的时空变化规律及治理方法   总被引:3,自引:0,他引:3  
利用2009─2012年丰水期和平水期的生物调查获取的环境和生物数据,研究太湖蓝藻的时空分布规律,分析蓝藻分布与其他物理、化学和生物因子(如温度、酸碱性、有机物和营养盐含量、浮游植物与浮游动物密度等)的相关关系。结果表明:太湖水质基本上超出V类地表水指标,主要的超标因子是总氮。总氮在丰水期和平水期的质量浓度分别为3.05 mg·L-1和1.65 mg·L-1,总氮在丰水期质量浓度降低的主要原因可能是丰水期蓝藻迅速生长,吸收了大量的营养盐。蓝藻仍是太湖浮游植物的优势种。2009─2012年太湖蓝藻的密度随年份无明显变化,但随季节和区域存在显著差异:丰水期蓝藻密度均值为4.87×10^7cell·L-1,明显高于平水期蓝藻密度(1.51×10^6 cell·L-1);太湖东部采样点蓝藻密度明显低于其他湖区。影响蓝藻的非生物因素包括温度、酸碱度和营养盐,高温、偏碱性和高营养盐含量都会增加蓝藻的密度。蓝藻与其他浮游植物和大型水生植物之间存在竞争关系,蓝藻密度增加促进了枝角类的生长。推荐利用机械打捞和大型水生植物修复方法,因为这2种方法可在降低蓝藻密度的同时去除水体中的有机物和营养盐,可以从根本上降低太湖蓝藻水华的风险。增加其他藻类和枝角类控制蓝藻水华方法可行性较差:1)蓝藻暴发时期其它藻类对能量和营养的竞争能力弱于蓝藻,难以抑制蓝藻的生长;2)在太湖中增加枝角类可能降低现有蓝藻的密度,但建立完整的食物链体系降低富营养化程度,防范生物调控中可能存在的生态风险(如其他藻类水华等)较困难。  相似文献   

12.
资源性供给紧约束条件下的消费理论研究述评   总被引:1,自引:0,他引:1  
许进杰 《生态环境》2010,19(7):1739-1743
通过对国内外关于资源性供给紧约束条件下的消费理论研究的文献回顾,认为在资源环境问题日益严峻的现代社会,深入分析和探寻人与自然和谐共处的居民消费行为,客观上要求我国必须从伦理学、社会学、生态学和法学等多学科领域进行探讨和研究,而不能仅局限于经济学学科研究领域。加快构建生态文明型消费模式,不仅是目前消费理论创新研究的重要方向,而且也是我国贯彻落实科学发展观,实现人口消费与社会、经济、资源和环境全面协调可持续发展的必然选择。  相似文献   

13.
Temporal and spatial distribution patterns of a population of Talitrus saltator living on the Tyrrhenian coast of Tuscany (Italy) were studied. Bimonthly surveys were performed from March 1991 to January 1992 along transects using a standard system of pitfall traps and sieves for surface-active and burrowed individuals, respectively. Captured individuals were subdivided into sex and age classes (on the basis of the number of articles of the flagellum of the second antenna). Abundances were calculated for each sampling period and sex ratios were determined. For each sampling period the mean hour of surface activity was calculated together with the mean zonation of both surface-active and burrowing sandhoppers belonging to the different sex and age classes. Shifts in mean zonation between the resting and active phase were also determined. For each category of sex, age, and reproductive phase, simple and multiple regression analyses were used to find relationships of the mean zonation of surface-active animals with climatic data, and of the number of burrowed individuals with surface sand parameters recorded in correspondence to the sieves. On the whole, the results show that this Tyrrhenian population of T. saltator exhibited a bivoltine reproductive cycle and that the sex ratios of active sandhoppers were male or female biased according to the season. The variations in the mean hour of surface activity and in the zonation patterns of sandhoppers depended more on the age than on the sex. Furthermore distribution patterns were generally related to seasonal changes in the local climatic and substrate parameters. The observed differences between burrowing and activity zonations were interpreted on the basis of the nocturnal migrations of the different categories.  相似文献   

14.
王丽红  陈惠茹  周青 《生态环境》2013,(11):1819-1824
为了解土壤中铜(Cu)与锌(Zn)对不同乔木抗氧化系统的复合影响及植物生态修复土壤cu和Zn复合污染的生理生化基础,以香樟(Cinnamomumcamphora)、广玉兰(Magnolia grandiflora)和榉树(Zelkovaschneideriana)3种乔木为实验材料,采用土培盆栽方法,研究单-Cu2+(75mg·L-1)溶液和单一Zn2+(210mg·L-1)溶液及两者复合溶液污灌对香樟、广玉兰和榉树叶片丙二醛(MDA)含量、脯氨酸(Pro)含量、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性的动态影响。结果表明,Zn2+/t~用下3种乔木MDA含量升高,Cu2+作用下MDA含量降低,Zn2+和Cu2+复合作用下3种乔木MDA含量低于Zn2+作用,即210mg-L。Zn2+对3种乔木生长的毒害作用比75mg·L。Cu2+明显,两者复合作用使Zn2+的伤害作用减轻。随胁迫时间延长,香樟POD和CAT活性增加,MDA含量和Pro含量减少。广玉兰细胞活性氧代谢失衡,POD活性和CAT活性急剧上升,第7天时分别达到1243.89%和300.00%(单一Cu2+’)、149.22%和60.00%(单一Zn2+)、653.96%和170.00%(Cu2+和Zn2+复合作用)。榉树无法承受高浓度Cu2+和Zn2+伤害而死亡。综合考虑,Zn2+对3种乔木伤害严重,Cu2+在诱导POD和CAT活性过程中与zn2+存在拮抗作用,香樟对重金属Cu2+和zn2+的耐性最强。  相似文献   

15.
现代社会大量化学品的生产与广泛使用造成了地表水、地下水、沉积物、土壤等环境受到污染,并对人体健康和生态系统构成威胁。基于毒性效应的关键致毒物质鉴别技术(effect directed analysis,EDA)已经在水体、沉积物的致毒物筛选方面得到了一定的应用。但是由于污染物组成复杂、范围广、基质干扰高、同分异构体广泛存在、人工合成标样缺少等问题,非目标致毒化合物的鉴别成为了EDA的瓶颈技术。逐渐发展的色谱与质谱技术、数据库指标在化合物筛选识别中发挥了重要作用。本文综述了基于高分辨质谱,数据库搜索,色谱保留特征,模型构建来筛选识别化合物的方法,总结了近年来化合物筛选识别方法在环境新型污染物及药物筛选等方面的应用并分析了化合物筛选识别所存在的问题与应用前景。这些方法可以提高非目标化合物筛选的准确性和通量,减少样品复杂性和基质干扰带来的负面影响,从而有利于未知化合物的确定。  相似文献   

16.
城市大气总悬浮颗粒物与城市热岛   总被引:7,自引:3,他引:7  
周凯  叶有华  彭少麟  粟娟 《生态环境》2006,15(2):381-385
城市大气总悬浮颗粒物是造成全球大部分城市空气污染严重的原因之一,世界各国对之已进行过很多的研究。大量的研究显示,总悬浮颗粒物的污染非常严重,是影响城市空气质量的首要污染物。总悬浮颗粒物的源以人为来源为主,其汇则以湿沉降为主。总悬浮颗粒物对城市气候的影响主要通过2种方式:一种是通过散射或吸收太阳辐射直接影响气候;另一种是以云凝结核的形式改变云的光学特性和云的分布而间接影响气候。但是总悬浮颗粒物与城市热岛相互关系的研究目前还未受到应有的关注,总悬浮颗粒物与城市热岛的相互作用尚未有定论,总悬浮颗粒物既有促进城市热岛形成,也有促进城市冷岛形成的研究报道。文章认为可从如下3个方面探讨总悬浮颗粒物与城市热岛的相互关系:(1)总悬浮颗粒物在城市热岛中的贡献;(2)总悬浮颗粒物影响城市热岛的作用机理;(3)总悬浮颗粒物与城市植被和城市热岛的相互关系及植被对总悬浮颗粒物的净化、对城市热岛的缓解。研究总悬浮颗粒物与城市热岛的相互关系为制定科学合理的城市大气总悬浮颗粒物污染防治措施,有效缓解现代城市热岛难题提供理论依据。  相似文献   

17.
将地理信息系统 (GIS)与景观格局分析软件FRAGSTATS相结合 ,选取了 9个斑块类型指标和 13个景观指标 ,从区域和绿洲 2个尺度分析了金塔县及其境内的金塔农业绿洲和鼎新农业绿洲的景观格局。结果显示 ,区域尺度的景观格局体现了绿洲与戈壁等基质类型景观的镶嵌特征 ;金塔农业绿洲体现出冲、洪积三角洲的特征 ,即耕地从扇顶呈放射状与盐碱地相间分布 ;鼎新农业绿洲显示了沿河绿洲的特点 ,即景观类型以河道为轴对称分布。指出划定绿洲界限和提高数据分辨率是揭示绿洲景观格局与过程相互作用机制的关键  相似文献   

18.
基于中国农业科学院红壤实验站红壤旱地小麦-玉米轮作长期定位试验,采用静态箱/气相色谱法,研究红壤旱地连续施肥16 a后,不同施肥条件下小麦季和玉米季土壤CO2和N2O的排放特征。结果表明,CO2和N2O排放具有明显的季节性,施肥对土壤CO2和N2O排放有明显影响,且有机肥的施用显著促进了土壤CO2和N2O排放。不施肥对照(CK)、氮磷配施(NP)、氮钾配施(NK)、氮磷钾配施(NPK)和有机无机肥配施(NPKM)处理小麦季和玉米季土壤CO2累积排放量分别为5 904、8 062、4 298、9 235、14 098和4 708、7 530、5 435、7 089、15 472 kg.hm-2,土壤N2O累积排放量分别为0.34、0.63、0.44、0.62、1.00和0.25、0.39、0.35、0.52、1.73 kg.hm-2,小麦休闲期土壤CO2和N2 O累积排放量平均占小麦生长季的63.52%和28.43%,玉米休闲季平均占玉米生长季的49.98%和32.72%,说明休闲期土壤CO2和N2O累积排放量不容忽视。除玉米季NP、NK、NPK处理外,其他各处理小麦季和玉米季土壤CO2排放通量与5 cm深处土壤温度显著相关;而土壤N2O排放通量与土壤温度间均未表现出显著相关性;除NPKM处理外,其他各处理土壤CO2或N2O排放通量与土壤水分间相关性均未达显著水平。  相似文献   

19.
农田土壤重金属污染状况及修复技术研究   总被引:33,自引:0,他引:33  
重金属污染因具有毒性、易通过食物链在植物,动物和人体内累积,对生态环境和人体健康构成严重威胁。随着工业快速发展、农药及化肥的广泛使用,农田土壤重金属污染越来越严重,研究农田土壤重金属污染现状及修复技术对农产品安全具有重要意义。综合国内外农田土壤重金属污染状况,农田土壤重金属污染主要来源于固体废弃物堆放及处置、工业废物大气沉降、污水农灌和农用物质的不合理施用。该文综述了国内外有关农田重金属污染土壤修复技术(物理修复、化学修复、生物修复、农业生态和联合修复)的研究进展,并针对各种修复方法,阐述了其原理、修复条件、应用实例及其优缺点,重点论述了植物修复的机理和应用,提出了草本与木本联合修复可有效提高农田土壤重金属复合污染的修复效率,为农田土壤土壤重金属复合污染修复提出了新的途径。最后在对已有研究分析的基础上,提出了联合修复技术(如生物联合技术、物理化学联合技术和物理化学-生物联合技术)可以在一定程度上克服使用单一修复手段存在的缺点,可提高复合污染的修复效率、降低修复成本,未来应深入探索联合修复技术间的相互作用机理,以期为农田土壤重金属综合治理与污染修复提供科学依据。  相似文献   

20.
生物修复中有机污染物的生物可利用性   总被引:7,自引:0,他引:7  
论述了土壤和地下水生物修复中有机污染物的生物可利用性。污染物的可利用性对生物修复速率和生物强化效率有重要影响。生物可利用性是指土壤和地下水中的微生物或其胞外酶对有机污染物的可接近性,它受土壤理化性质、污染物和微生物性质、污染接触时问等许多因素的综合影响。污染物的介质吸附、多相分配、老化和形成非水相基质,以及土壤微生物的吸附、过滤和沉降作用降低了污染物的可利用性。促进土壤中污染物和微生物的解吸附,增强非水相基质的溶解,加速土壤污染物与微生物之间的质量传递,可以增强污染物的可利用性和生物降解的速率。施用表面活性剂和电动力学方法可有效地增强污染物的生物可利用性。  相似文献   

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