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1.
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   

2.
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   

3.
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   

4.
近十年生态工程在中国的进展   总被引:21,自引:0,他引:21  
我国生态工程近 1 0多年有进一步发展 ,研究和应用对象扩展为社会 -经济 -自然复合生态系统 ,目标明确为可持续发展 ,从追求一维的经济增长或环境与自然保护 ,走向富裕、健康、文明三维一体的复合生态繁荣。在充实“整体、协调、循环、自生”的生态工程原理和生态控制论的基础上 ,总结出生态工程设计的 8项原则。方法论发展为从物理过程的量化走向生态过程的序化 ,从工程结构的优化走向生态格局的进化 ,从机器的人工智能走向人的生态智能。技术路线发展了硬件、软件、心件耦合 ;多学科、多技术的系统组合 ;调控复合生态系统全生态过程 ;寓环境保护于生产和消费中 ,寓废弃物处理于利用中 ;结构和功能纵横耦合成食物链网式、生命周期式、生态系统式等网络结构  相似文献   

5.
在产业结构调整、优化过程中 ,必须从观念、管理和技术 3个层次上 ,加快传统产业改造、转型、升级及新兴产业发展 ,大力推进产业生态转型和建立生态产业。结合大量案例 ,论述了发展生态产业的原则和策略 ,主要有 :以市场为导向 ,生态与整体最优 ,竞争、共生、自生、再生相结合 ,减量化、再利用、资源化的循环经济 3原则 ,发挥区域优势 ,加强结构与功能的弹性和自我调节 ,硬件、软件和心件的耦合 ,创造更多就业机会  相似文献   

6.
Abstract: Climate change affects individual organisms by altering development, physiology, behavior, and fitness, and populations by altering genetic and phenotypic composition, vital rates, and dynamics. We sought to clarify how selection, phenotypic plasticity, and demography are linked in the context of climate change. On the basis of theory and results of recent empirical studies of plants and animals, we believe the ecological and evolutionary issues relevant to population persistence as climate changes are the rate, type, magnitude, and spatial pattern of climate‐induced abiotic and biotic change; generation time and life history of the organism; extent and type of phenotypic plasticity; amount and distribution of adaptive genetic variation across space and time; dispersal potential; and size and connectivity of subpopulations. An understanding of limits to plasticity and evolutionary potential across traits, populations, and species and feedbacks between adaptive and demographic responses is lacking. Integrated knowledge of coupled ecological and evolutionary mechanisms will increase understanding of the resilience and probabilities of persistence of populations and species.  相似文献   

7.
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   

8.
本文从环境保护的科学技术支持系统分析入手,以环境科学研究对象和内容为核心,依据系统结构的内在规定性、环境科技的横断性、综合性和环境科学活动的组织规律,提出了支持系统的结构模型和科技队伍合理配置方案,可为环保科技结构调整、分流重组和能力建设所参考.  相似文献   

9.
UV-B辐射使番茄叶片的叶绿素a,叶绿素b及总叶绿素含量先升高后降低,同样使叶片的抗氧化酶过氧化氢酶(CAT)和过氧化物酶(POD)活性先升高随后降低,而使超氧化物歧化酶(SOD)活性升高,膜脂过氧化产物MDA的含量增加;中等剂量(5mmol*l-1)的H2O2预处理能提高叶绿素b的含量,明显提高抗氧化酶的活性,并延缓CAT活性的降低,抑制膜质过氧化产物MDA的产生.中等浓度H2O2预处理能提高番茄对UV-B增强的抗性.  相似文献   

10.
进行农业非点源污染控制区划,识别出污染关键源区,可以提高非点源污染控制成效。通过清单分析定量核算农业非点源污染物(COD、TN、TP)排放量及排放浓度,并以非点源污染敏感性评价和污染类型划分为研究基础,探讨了农业非点源污染控制区划方法,提出了区划原则、分区方法和命名方法。该区划结果可以实现农业非点源污染的分级管理和分类控制。最后,以江苏省的64个县(市、区)作为基本单元(市辖区除外),采用该方法进行了农业非点源污染控制区划。  相似文献   

11.
改良剂对红蛋植物修复污染土壤重金属铅和镉效果的影响   总被引:3,自引:0,他引:3  
通过盆栽试验研究了在重度重金属混合污染土壤上,施用不同配比的石灰和泥炭(T1,泥炭0 g·kg^-1土,石灰2 g·kg^-1土;T2,泥炭30 g·kg^-1土,石灰0 g·kg^-1土;T3,泥炭50 g·kg^-1土,石灰0g·kg^-1土;T4,泥炭30 g·kg^-1土,石灰2g·kg^-1土;T5,泥炭50 g·kg^-1土,石灰2g·kg^-1土)对红蛋(Echinodorus osiris)生长及其去除污染土壤铅、镉量的影响,探讨了化学修复和植物提取修复技术相结合修复重金属污染土壤的可能性。研究结果表明,施用石灰显著提高了土壤pH,施用泥炭不显著;施用石灰和泥炭后土壤中交换态铅、镉含量较CK显著降低,红蛋地上部和地下部铅、镉含量较CK有不同程度降低,T4、T5处理降低不显著;T3、T4、T5处理显著地提高了红蛋的铅单株迁移量和年迁移量,年迁移量分别为CK的2.1倍、2.6倍和2.8倍;T1、T2、T3、T4、T5处理显著地提高了红蛋的镉单株迁移量和年迁移量,年迁移量分别为CK的1.8倍、2.9倍、2.9倍、2.8倍和2.9倍,其主要原因在于施用土壤改良剂改善了红蛋的生长,显著增加了地上部生物量。结合经济效益方面因素考虑,以施用泥炭30g·kg^-1土和石灰2g·kg^-1土的处理更适合推广运用。  相似文献   

12.
Green Toxicology refers to the application of predictive toxicology in the sustainable development and production of new less harmful materials and chemicals, subsequently reducing waste and exposure. Built upon the foundation of “Green Chemistry” and “Green Engineering”, “Green Toxicology” aims to shape future manufacturing processes and safe synthesis of chemicals in terms of environmental and human health impacts. Being an integral part of Green Chemistry, the principles of Green Toxicology amplify the role of health-related aspects for the benefit of consumers and the environment, in addition to being economical for manufacturing companies. Due to the costly development and preparation of new materials and chemicals for market entry, it is no longer practical to ignore the safety and environmental status of new products during product development stages. However, this is only possible if toxicologists and chemists work together early on in the development of materials and chemicals to utilize safe design strategies and innovative in vitro and in silico tools. This paper discusses some of the most relevant aspects, advances and limitations of the emergence of Green Toxicology from the perspective of different industry and research groups. The integration of new testing methods and strategies in product development, testing and regulation stages are presented with examples of the application of in silico, omics and in vitro methods. Other tools for Green Toxicology, including the reduction of animal testing, alternative test methods, and read-across approaches are also discussed.  相似文献   

13.
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   

14.
培育土壤中硫化细菌和硫酸盐还原细菌的消长特征初探   总被引:6,自引:0,他引:6  
通过不同含水量下潮土和褐土的培育试验,测定了土壤中硫化细菌和硫酸盐还原细菌的消长变化及水溶性硫、有机硫和盐酸挥发性硫的含量。结果表明,土壤中硫化细菌含量随土壤含水量的增加而有增大趋势,其消长变化与有机硫和盐酸挥发性硫的含量变化有关,硫酸盐还原菌含量亦随土壤含水量的增加趋于增大,潮土中硫酸盐还原菌的消长与水溶性硫含量呈显著相关,硫化细菌和硫酸盐还原细菌的消长曲线表明,这两类硫细菌的消长呈相反的变化趋势。  相似文献   

15.
Establishment of the chemical form and associations of trace elements is important in the scientific and medical fields related to environmental geochemistry and health. Fundamental understanding of trace-element behaviour, the realistic formulation of historical perspectives of trace-element contamination, an assessment of environmental transformation processes and a thorough appraisal of environment-related ill health and disease all depend on knowledge of the chemical speciation and partitioning of trace elements. These topics and the development of analytical speciation techniques and procedures are discussed with reference to trace-element studies in the Department of Forensic Medicine and Science, University of Glasgow, on lacustrine sediments and water, the atmosphere, soil and street dirt of an urban environment and human biological fluids.  相似文献   

16.
针对中国植物园稀有濒危植物的保护现状和存在问题进行分析,重点讨论了稀有濒危植物在植物园迁地保护的有效性问题,涉及稀有濒危植物在植物园迁地保护的生长和适应问题、稀有濒危植物在植物园重复栽培问题、稀有濒危植物在植物园迁地保护的有效种群大小问题、科学记录系统和监测中心的建立问题。就稀有濒危植物在植物园迁地保护的可持续发展提出了若干对策与建议:以植物园为基础形成保护的网络系统;加强稀有濒危植物迁地保护规划并突出重点;加强科学记录系统和监测中心的建立;多方筹措资金,加强支持强度;加强人才培训与学术交流。  相似文献   

17.
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   

18.
敦煌地区严重的生态环境退化问题,其根源在于对其产生的原因及其演变过程没有科学、统一的认识.尽管近年来政府及有关部门投入了大量的人力物力,采取了一些措施,做了一些研究,但效果并不明显,甚至有人提出将之与古楼兰衰退相提并论.该文认为,敦煌地区生态退化及其演变,无论是地下水位的下降、绿洲与湿地的萎缩等,都是地质科学领域的问题,需要运用地质学思维分析探讨.研究改善敦煌的生态环境退化和治理措施,必须从环境地质、生态地质学的理论和方法去解决.图1,参13.  相似文献   

19.
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   

20.
不同施肥水平下菜地径流氮磷流失特征   总被引:6,自引:0,他引:6  
研究施肥对菜地径流氮、磷流失的影响,对控制水体富营养化有重要意义。采用田间小区监测的方法,研究常规施肥、减量施肥1和减量施肥2等三种施肥水平对菜地径流氮磷流失的影响。结果表明,(1)不同施肥水平的径流氮、磷流失浓度均较高,径流TN、NH4+-N、NO3--N的平均流失质量浓度分别在20.5~34、2.2~2.4、6.3~9.5 mg L-1之间,径流TP、DP的平均流失质量浓度分别在7.7~11.1、2.1~2.4 mg L-1之间,菜地土壤径流氮、磷流失风险较大。(2)减量施肥可明显降低径流TN和NO3--N的流失浓度,与当地常规施肥相比,减施肥料20%和30%可分别降低径流TN流失浓度的40%、32%和NO3--N流失浓度的23%、35%,而减量施肥对径流TP、DP的流失浓度影响不大。(3)不同施肥水平的径流TN、NO3--N流失负荷分别在5.8~7.6、1.6~2.3 kg hm-2之间,与常规施肥相比,减施肥料20%和30%可分别减少TN、NO3--N流失负荷的24%、19%和11%、29%。不同施肥水平的径流TP、DP流失负荷分别在1.7~2.9、2.5~2.7 kg hm-2之间,减量施肥并不能减少径流TP、DP的流失负荷。  相似文献   

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