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1.
苔藓植物对环境变化的响应及适应性研究进展   总被引:4,自引:0,他引:4  
苔藓植物由于其结构相对简单,对环境变化的反应较为敏感,是一类良好的生物指示植物.本文综述了水分、光照、温度等方面的环境因子变化对苔藓植物的影响以及苔藓植物对环境污染的响应及适应的最近研究进展,以期促进国内深入开展苔藓植物对环境污染和全球变化的响应、适应及其生态指示作用等研究.  相似文献   

2.
苔藓植物对环境变化的影响及适应性研究进展   总被引:28,自引:3,他引:25  
苔藓植物由于其结构相对简单,对环境变化的反应较为敏感,是一类良好的生物指示植物,本文综述了水分、光照、温度等方面的环境因子变化对苔藓植物的影响以及苔藓植物对环境污染的响应及适应的最近研究进展,以期促进国内深入开展苔藓植物对环境污染和全球变化的响应、适应及其生态指示作用等研究。  相似文献   

3.
The assessment of different policy options represents a major tool for decision-makers in Biosphere Reserves, to develop more-resilient strategies for sustainable development and to visualise unintended consequences of these policies.In this work we analyse eight measures proposed by different agents in order to meet the main objectives of environmental sustainability, included in the Action Plan of the Fuerteventura Biosphere Reserve (Spain). We quantified the effects of these measures in terms of the sustainability thresholds of 10 environmental indicators, also proposed by the Action Plan, which was integrated in the Fuerteventura Biosphere Reserve dynamic model. Their behaviours under these measures allow determination of whether the objectives will be met in the period 2012–2025. Although some indicators would improve under these measures, fitting certain objectives, some negative effects on other indicators confirm the existence of trade-offs among these objectives. For instance, grazing limitation would improve the proportion of high-quality vegetation but would negatively affect the Egyptian vulture population, which would even fall below its sustainability threshold. The definition of thresholds for each indicator allows decision-makers to establish a way to prioritise among the eight measures analysed. The results show that these measures are insufficient to meet the sustainability thresholds of four indicators (the landscape indicator, the proportion of renewable energy, the per capita primary energy consumption and carbon dioxide emissions). Focusing on the remaining six indicators and following the rule “Threshold out, measure out”, seven out of the eight measures would exceed some thresholds and should be avoided. Only one option, aimed at growing fodder to feed cattle on restored traditional agricultural lands, would not exceed any of these thresholds. However, this measure also presents certain negative effects regarding indicators related to flagship species (the houbara habitat and the Egyptian vulture population), which would require compensation measures.  相似文献   

4.
微生物固定化及其在环境污染治理中的应用研究进展   总被引:2,自引:1,他引:1  
微生物固定化技术广泛应用于食品、轻化以及环保领域,其具有微生物密度高、生物活性好、环境适应性强、可反复利用等优点。本文对微生物固定化技术进行了概述,并通过典型案例重点阐释了其在水、土和大气等环境污染治理领域的应用进展。在水环境中,固定化载体可为不同类型微生物提供生存微环境和各自所需的生态位,提高了系统负荷和处理效能;在土壤环境中,其重要作用在于提高土壤中污染物的生物有效性,从而提升微生物修复效果;空气污染治理领域则更注重载体的机械强度及气液传质能力的提高。本文比较总结了微生物固定化技术在不同环境治理领域中的应用特点和优势,以期为今后的环境污染治理提供一定的参考。  相似文献   

5.
Consumption of contaminated drinking water is a significant cause of Campylobacter infections. Drinking water contamination is known to result from septic seepage and wastewater intrusion into non-disinfected sources of groundwater and occasionally from cross-connection into drinking water distribution systems. Wastewater effluents, farm animals and wild birds are the primary sources contributing human-infectious Campylobacters in environmental waters, impacting on recreational activities and drinking water sources. Culturing of Campylobacter entails time-consuming steps that often provide qualitative or semi-quantitative results. Viable but non-culturable forms due to environmental stress are not detected, and thus may result in false-negative assessments of Campylobacter risks from drinking and environmental waters. Molecular methods, especially quantitative PCR applications, are therefore important to use in the detection of environmental Campylobacter spp. Processing large volumes of water may be required to reach the desired sensitivity for either culture or molecular detection methods. In the future, applications of novel molecular techniques such as isothermal amplification and high-throughput sequencing applications are awaited to develop and become more affordable and practical in environmental Campylobacter research. The new technologies may change the knowledge on the prevalence and pathogenicity of the different Campylobacter species in the water environment.  相似文献   

6.
As cities represent the microcosms of global environmental change, it is very important for the global sustainable development by decoupling environmental pressure from economic growth on city level. In this paper, the municipality of Chongqing in China is employed as a case to show whether the decoupling of environmental pressures from economic growth has occurred in cities undergoing rapid economic growth; what is the level of decoupling; and what causes the observed degree of decoupling. Results show the following. (1) During the period of 1999–2010, decoupling from economic growth has been absolute for the emissions of SO2, soot, and waste water, while it has been relative for total energy consumption, emissions of CO2 and solid waste. (2) Compared with the period 2000–2005, decoupling level improved for all the six environmental pressures in the period 2005–2010. (3) Compared with China and other three municipalities of China, the overall decoupling level of Chongqing is above China’s average while below those of Beijing and Shanghai. (4) During the period 1999–2000, technological change was the dominate factor for decoupling Chongqing’s environmental pressure from economic growth, as it contributed 131.4%, 134.6%, 99.9%, 97.7%, 104.5% and 54.9% to the decoupling of total energy consumption, emissions of CO2, SO2, soot, waste water and solid waste, respectively; while economic structural change had very tiny effect to the decoupling of emissions of soot and SO2, and it even had negative effect to that of total energy consumption, and emissions of CO2 and waste water. Based on the above observations, we explain the difference in decoupling levels for different environmental pressures and suggest approaches for policy-makers on further promoting decoupling environmental pressure from economic growth.  相似文献   

7.
光、温度、水分等环境因素影响植物的生长发育,植物可以通过启动子中顺式作用元件与转录因子的相互协调作用,对这些信号产生响应,调控基因表达。本文综述了光、温度、水分诱导表达启动子中的顺式作用元件及相关转录因子研究的最新进展,从分子水平上探讨了环境因子诱导的基因表达调控,对研究植物适应环境的机制具有一定的意义。  相似文献   

8.
环境因子对硬骨鱼类性腺发育成熟及其排卵和产卵的调控   总被引:21,自引:2,他引:21  
对影响硬骨鱼类性腺发育成熟及其排卵和产卵的诸多环境因子进行了综述(如水温、光照、降雨和水流、水体化学因子、水体生物因子以及环境污染(环境胁迫)等),并对其调控机制进行了阐述,侧重强调了环境胁迫对硬骨鱼类生殖的影响,旨在从生态学角度为保护鱼类种质资源提供对策。  相似文献   

9.
Air pollution is the single largest environmental risk today and is increasing in developing countries. In addition, exposure to air pollution is correlated to poor socioeconomic conditions owing to political processes and cultural and historic occupation of land. Ports have several structures that are potential emitters of pollutants such as large ship engines, diesel trucks, and trains. Owing to the considerable costs of implementing direct monitoring networks, alternatives like biomonitoring are an interesting approach to evaluate the environmental status of a particular area using living organisms or their parts such as bark, even though the use of bark as a biomonitor has several problems such as difficulties in determining the exposure period and its correlation with human exposure. Therefore, the use of a complementary mathematical logic is necessary. This study describes a methodological approach to evaluate the environmental risk from air pollution integrating data on environmental pollutants from tree bark using Fuzzy logic, based in the port city of Paranaguá in the state of Paraná in Brazil, and validated using income indicators. The results indicate that the risk distribution patterns have an inverse relationship with the income indicator, i.e., higher risk levels indicate lower income levels and vice versa. It was concluded that the system was able to identify the distribution of risk and that there is a context of environmental injustice in the region, where the environmental risk related to air pollution is inversely proportional to income levels. This type of information provides a decision making tool for environmental risk analysis from air pollution and can be used in the definition of public policies.  相似文献   

10.
基于生态需水保障的农业生态补偿标准   总被引:1,自引:0,他引:1  
庞爱萍  孙涛 《生态学报》2012,32(8):2550-2560
面向流域农业需水和生态需水间的矛盾问题和协调发展的要求,提出了基于生态需水保障的农业生态补偿标准计算方法。其中考虑农业用水定额计算基于生态需水保障的农业用水短缺,引入水分生产函数模型建立保障生态需水量产生的农业用水短缺与产量损失间的关系,根据不同季节作物产量响应系数的变化,定量确定具有时间和等级差异性的农业生态补偿标准。以保障黄河口生态需水引起的山东引黄灌区农业损失补偿标准分析为实例,计算了冬小麦和夏玉米种植户不同等级的生态补偿标准。结论认为,农业生态补偿标准需根据不同的来水过程及生态需水等级确定,面积稳定和保障功能显著的粮食作物应作为补偿标准计算的依据。  相似文献   

11.
Due to the rise of environmental concern ecologists have been asked for advice more frequently since the late 1960s. This article discusses how the changing relationship between ecologists and society has affected the behaviour of one particular group of ecologists, namely Dutch fresh water ecologists, by focussing on their behaviour towards job market control and public interest activities. The analysis has been based on interviews with 65 Dutch fresh water ecologists together with an analysis of their publications.In contrast with American ecologists, Dutch fresh water ecologists have made little effort to control their job market by formal arrangements such as formulating a code of ethics and certification procedures. Secondly, Dutch fresh water ecologists generally conceive of their own role in contributing to the solution of environmental problems in relation to that of the environmentalists by doing good research and reliable advisory work. Although a significant number of researchers also address lay publics by writing popular articles and/or holding lectures, only a minority actively participates in environmental politics.  相似文献   

12.
Abstract In this study we tried to detect DNA Naegleria fowleri in artificially contaminated environmental samples, with or without sediments, containing 104 cysts of this pathogenic amoeba. We used two assays to extract DNA from samples: first, direct DNA extraction, which gave positive results only for water samples without sediment; second, DNA extraction after sample incubation on agar plates, which allowed us to remove amoeba growing out of the sediments, and which gave positive results for all samples, even those initially with sediments (5, 500 or 500 mg). Thus, this molecular identification appears as a powerful tool to investigate N. fowleri growth in environmental samples.  相似文献   

13.
As the largest developing country, China has been suffering from resource shortage and serious environmental pollution. Evaluation and improvement of the regional environmental efficiency is crucial to pursuing the balance between economic development and environmental protection. This paper used a regional environmental efficiency SBM (slack-based measure) (REES) model which treats environmental pollution as undesirable outputs to evaluate the environmental efficiency of 30 provincial administrative regions (PARs) in China from 2005 to 2011 and investigated the factors affecting environmental efficiency using the Tobit regression model. The results indicate that there is distinct difference in environmental efficiency amongst each PAR. The GDP per capita, industrial structure, innovation capability, environmental awareness of local government and population density have significant positive impacts, while energy intensity exerts a significantly negative effect on environmental efficiency. In order to make more effective policies for improving China’s regional environmental efficiency, the hierarchical cluster analysis was applied to divide the 30 PARs into 3 sub-regions. A number of policy recommendations were provided for improving environmental efficiency according to the characteristics of each sub-region, which are helpful for the Chinese government to achieve the targets of environmental protection along with the economic development in the coming years.  相似文献   

14.
Communicating change in environmental condition is a critical component of non-market valuation studies. However, the underlying assumptions and implications associated with alternative ways of expressing change in environmental condition for surveys are rarely discussed in the literature. Our review found no cases where alternative formulations were both discussed and tested. In this note we report on our multi-disciplinary analysis of how best to express such change. We interrogate the meaning of, and inferences from, four formulations for quantitative expressions, or metrics, of environmental indicators that are used in the field of ecology and we then evaluate their usefulness in non-market valuation. The assumptions and limitations of each formulation are discussed using seven hypothetical cases of change in environmental condition. We show that formulations for expressing change can be grouped based on two inherent philosophies potentially held by people when they consider their preferences for environmental changes: ‘more is better philosophy’ and ‘restoration philosophy’. We contend that, without careful consideration of which philosophy people may apply, it is possible to inadvertently bias respondent choices when a particular formulation is used in a valuation study. If this happens, resulting value estimates will be a poor reflection of what researchers seek. An alternative approach that does not presuppose a philosophy but instead helps reveal a respondent’s philosophy, is proposed.  相似文献   

15.
丛毛单胞菌在环境污染物降解方面的研究进展   总被引:2,自引:0,他引:2  
赵燕  薛林贵  李琳  张红光 《微生物学通报》2012,39(10):1471-1478
环境污染物的微生物降解是环保领域研究的一个热点。研究发现,丛毛单胞菌对多种污染物有很好的降解效果。综述目前已分离的一些丛毛单胞菌对不同污染物的降解特性、代谢途径,并分析了影响其降解效果的各种因素,介绍应用现状并对前景进行展望。  相似文献   

16.
应用典范对应分析(CCA)对长白山北坡静水水体12个样点中28种水甲虫与环境关系的研究表明,长白山5种环境因子中水底腐殖化程度和海拔对水甲虫的分布起主要作用,与排序轴的相关系灵敏分别高达0.8371和0.7206,而水温和植被密度也有较大的影响,在环境因子的影响下不同生境中水甲虫分布的种群不同,深刻斜凹龙虱,端钩切眼龙虱,布朗沟牙甲,沼梭科水甲虫等主要分布在深水区,与水温没有关系。而异毛龙虱和舟型牙甲等与海拔和水泡子的腐殖化程度呈正相关。  相似文献   

17.
Non-native marine species have been and continue to be introduced into Puget Sound via several vectors including ship's ballast water. Some non-native species become invasive and negatively impact native species or near shore habitats. We present a new methodology for the development and testing of taxon specific PCR primers designed to assess environmental samples of ocean water for the presence of native and non-native bivalves, crustaceans and algae. The intergenic spacer regions (IGS; ITS1, ITS2 and 5.8S) of the ribosomal DNA were sequenced for adult samples of each taxon studied. We used these data along with those available in Genbank to design taxon and group specific primers and tested their stringency against artificial populations of plasmid constructs containing the entire IGS region for each of the 25 taxa in our study, respectively. Taxon and group specific primer sets were then used to detect the presence or absence of native and non-native planktonic life-history stages (propagules) from environmental samples of ballast water and plankton tow net samples collected in Puget Sound. This methodology provides an inexpensive and efficient way to test the discriminatory ability of taxon specific oligonucleotides (PCR primers) before creating molecular probes or beacons for use in molecular ecological applications such as probe hybridizations or microarray analyses. This work addresses the current need to develop molecular tools capable of diagnosing the presence of planktonic life-history stages from non-native marine species (potential invaders) in ballast water and other environmental samples.  相似文献   

18.
Increased international cooperation to limit transboundary and global environmental problems, increased sectoral responsibility and decentralization, and improved information and statistics on the state of the environment are the main lines for the development of future environmental policy. For lakes, watercourses, and the seas the overall objective is to maintain viable, balanced populations of naturally occurring species. Pollution is not to limit the use of water for fishing, recreation, or water supply. Foreign species or organisms subjected to genetic mutation are only to be introduced with great restriction. Measures are suggested that will reduce environmental disturbances from agriculture and forestry, traffic, energy production, industry, goods, chemical products, and waste.Paper presented at Seminar on Ecosystems Approach to To Water Management (Oslo, Norway, 27–31 May 1991).  相似文献   

19.
We examined fossil chironomids (Diptera: Chironomidae) in the surface sediments of four maar lakes in western Alaska to determine chironomid distribution patterns with respect to within-lake gradients of water depth, LOI (loss-on-ignition), and bottom-water temperature. Linear and non-linear regressions were undertaken to test whether the within-lake distributions of fossil chironomids were uniform. Additionally, water depths where abrupt changes or breakpoints in the assemblages occur were identified using piecewise regression. Direct gradient analysis was then used to examine variation in the assemblages explained by the environmental data. For the shallowest lake, chironomid abundances of individual taxa and inferred temperatures varied little within the lake. For the three deep lakes, seven of the sixteen commonest fossil taxa varied significantly with water depth, although some lake-specific patterns were evident. Water depth was generally identified as the principal environmental variable in explaining variation in the assemblages, although sediment organic matter content and bottom-water temperature were also important. Abrupt changes in assemblages occurred at different water depths in each lake, and at only one lake did the breakpoint occur within the range of water depths defining the thermocline. Chironomid-inferred temperature trends from the lakes also showed depth-related patterns: the warmest inferred temperatures were generally from both the shallowest and deepest water depths, whereas intermediate depths yielded temperature inferences about 0.5 to 1.0°C cooler than the average within-lake value. Nevertheless, we conclude that these patterns had only a slight impact on temperature reconstructions relative to the prediction error of the model. A greater understanding of taphonomic processes is needed to determine their influence on environmental reconstructions based on chironomids. Handling editor: J. Saros  相似文献   

20.
Effective environmental management requires monitoring programmes that provide specific links between changes in environmental conditions and ecosystem health. This article reviews the suitability of a range of bioindicators for use in monitoring programmes that link changes in water quality to changes in the condition of coral-reef ecosystems. From the literature, 21 candidate bioindicators were identified, whose responses to changes in water quality varied spatially and temporally; responses ranged from rapid (hours) changes within individual corals to long-term (years) changes in community composition. From this list, the most suitable bioindicators were identified by determining whether responses were (i) specific, (ii) monotonic, (iii) variable, (iv) practical and (v) ecologically relevant to management goals. For long-term monitoring programmes that aim to quantify the effects of chronic changes in water quality, 11 bioindicators were selected: symbiont photophysiology, colony brightness, tissue thickness and surface rugosity of massive corals, skeletal elemental and isotopic composition, abundance of macro-bioeroders, micro- and meiobenthic organisms such as foraminifera, coral recruitment, macroalgal cover, taxonomic richness of corals and the maximal depth of coral-reef development. For short-term monitoring programmes, or environmental impact assessments that aim to quantify the effects of acute changes in water quality, a subset of seven of these bioindicators were selected, including partial mortality. Their choice will depend on the specific objectives and the timeframe available for each monitoring programme. An assessment framework is presented to assist in the selection of bioindicators to quantify the effects of changing water quality on coral-reef ecosystems.  相似文献   

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