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1.
水电工程的规模和特点决定了它对环境的影响特别重大,这种影响有正效益和负效益两个方面。水电开发的环境影响评价理论和方法在世界范围内都是一个在不断探索、发展和完善的科学问题。本文以怒江中下游水电开发规划为例,通过怒江水电开发规划环境影响因子的筛选和环境影响的定量分析,对开发方案的长期和整体的环境影响效益和成本进行估算,即估算项目实施后年环境成本和效益流量。评价结果表明,怒江中下游4级水电开发的直接环境效益为2.77×108元/a,环境成本总值约为3.96×108。评价结果中,直接环境效益和环境成本的比值为1∶1.4,环境影响的净现值为-1.19×108元/a;限于目前环境损益分析技术和方法还不太成熟,部分指标如怒江水电开发对文化多样性、陆生生物、水生生物等的影响,还无法找到有充分说服力的评价方法,从而使评价结果的完整性和准确性受到一定的影响。作为辅助决策依据,决策者应根据多方面的因素,综合考虑,以做出充分合理的判断和决策。  相似文献   

2.
关于我国国民环境的态度调查   总被引:4,自引:1,他引:3  
曹世雄  陈军  陈莉  高旺盛 《生态学报》2008,28(2):735-741
2004年10月随机抽取了北京、上海、河北、河南、湖南、陕西六省市对5000余位国民做了环境态度问卷调查.了解我国民众的生态观念、制约因素、以及潜在的保护环境的动机.调查结果显示,91%的被访者感到我国环境已严重恶化,78%的被访者支持政府耗资3000多亿元人民币开展退耕还林项目.居民的环境意识同经济收入、受教育水平、年龄、职业、居住环境有着密切关系,其中经济收入和受教育水平是影响居民环境意识变化的首要因素.区域差异分析结果表明,我国现阶段的环境压力主要集中在贫困的边远山区和快速崛起的城市周边地区,把发展经济、改善教育、提高居民的生活质量与环境修复有机地结合起来,是生态政策管理的根本途径.  相似文献   

3.
A survey of 36 fields across 11 farms in the North of England was conducted to record the plant species diversity of grassland communities under various base conditions. Data pertaining to topographical advantage, farm management strategy and soil type were also collected for each field site. The relationship between management inputs and base environmental conditions and the resultant diversity of flora were identified through ordination techniques. The results show a total of 111 species being observed across the sample and some expected relationship emerge, but they also suggest that complementary management techniques can have opposing or conflicting effects on species prevalence. The study argues that provision or use of such information should be paramount within environmental policy formulation where site-specific management plans are used to produce environmental goods.  相似文献   

4.
The Ranee basin, on the northern coast of Brittany, is the only site where a full-scale evaluation of the ecological impact of a tidal power scheme, after 20 years of operation, has been made. The isolation of the estuary, during the construction phase, was particularly damaging to the environment. Gradually, after the scheme was put into service, an increasingly diverse flora and fauna became established. The patterns of distribution of this flora and fauna, their groupings into ecological units and the nature of their interrelationships, indicate a variable degree of biological adjustment to the new environmental conditions. Migratory organisms are able to pass via sluice gates and turbines. However, the new ecological equilibrium, established in the space of 10 years, remains fragile and, being linked to the degree of stability of abiotic conditions, depends to a large extent on the operating conditions of the power station.  相似文献   

5.
This article explores the intrinsic role of context in shaping the course and outcomes of interventions aimed at changing environmentally significant behavior in home and workplace settings. Drawing on sociological theories of symbolic interactionism, we evaluate the social dynamics and mechanisms of two similar, team-based behavior change interventions at work (Environment Champions) and at home (EcoTeams). The analysis shows that the interventions open up different levels of opportunity for reviewing and renegotiating new environmentally friendly behaviors against the reactions and expectations of the immediate peer group, existing workplace or domestic roles, and the situation-specific definitions of what counts as appropriate behavior in the home and the workplace. We argue that policy studies should pay greater attention to the processes of behavior change, or the contextually sensitive relationship between interventions and outcomes, as a step toward refining or streamlining interventions aimed at changing environmentally significant behavior.  相似文献   

6.
植物气孔导度的环境响应模拟及其尺度扩展   总被引:5,自引:0,他引:5  
气孔导度是衡量植物和大气间水分、能量及CO2平衡和循环的重要指标,探讨气孔导度与环境因子的关系及其模拟,以及气孔导度在叶片、冠层及区域尺度间的尺度转换及累积效应,对更好地认识植被与大气间的水热运移过程,合理评价植被在陆面过程中的地位和作用都具有重要意义。从植物气孔导度与环境因子的关系、气孔导度模拟以及尺度扩展三个方面,对前人的研究成果进行了概括总结。从叶片和冠层两个尺度出发,归纳总结了前人对于不同植物气孔导度与环境因子关系的研究成果,发现由于不同植物的遗传特性、测定时的环境、时间尺度的不同,以及未考虑各个环境因子的相互作用对气孔导度的影响,由此得到的气孔导度与环境因子之间的关系也不尽一致。对各单一环境因子与气孔导度的关系,给出了生理学解释,从根本上说明了环境因子变化对气孔导度的影响,而研究环境因子对气孔导度的综合影响时,应对各环境因子进行系统控制与同步观测。模拟计算植物气孔导度的模型主要有Jarvis模型和BWB模型两类,这些模型的模拟能力随着研究对象、试验区域、环境条件的改变而存在一定的差异,在具体使用时应结合实际情况选择最优模型进行模拟。除上述常用模型外,还总结了其他学者分别从不同角度提出的新的模型,对现有气孔导度模型进行了全面的总结。从叶片-冠层、冠层-区域两个方面归纳总结了前人关于气孔导度尺度扩展的研究成果,发现叶片-冠层的尺度扩展研究较成熟而冠层-区域的尺度扩展在模拟精度的验证方面存在困难。针对以下几个方面提出了今后气孔导度的研究重点:(1)结合研究对象所在的区域及环境条件,选择最优模型进行模拟;(2)综合考虑环境因子之间的相互作用及其对气孔导度的累积影响;(3)BWB模型与光合模型的耦合;(4)提高大尺度范围内的气孔导度模拟精度。  相似文献   

7.
基于环境DNA宏条形码技术的秦淮河生物多样性研究   总被引:1,自引:0,他引:1  
秦淮河是南京的母亲河,其生物多样性受城市化进程影响面临严重威胁,而物种资源调研是生物多样性保护的基础。环境DNA宏条形码技术较形态学监测是一种简单高效、灵敏度高的新型监测技术。为探究秦淮河浮游生物、底栖动物及鱼类的生物多样性,于2019年7月,采用环境DNA宏条形码技术对其进行了探究,并分析了秦淮河上下游间的差异及环境因子对其群落结构的影响。结果表明:秦淮河共监测到浮游动物13属22种407个操作分类单元(Operational Taxonomic Units, OTUs),浮游植物85属60种4445个OTUs,底栖动物16属17种212个OTUs,鱼类53属44种1663个OTUs。其中浮游动物以游泳轮虫目(Ploima)和双甲目(Diplostraca)为主,共占浮游动物63.37%,浮游植物以隐藻门(Cryptomonas)和褐藻门(Ochrophyta)为主,共占浮游植物88.11%,底栖动物中节肢动物门(Arthropoda)占比最高,达91.67%,鱼类中鲤形目(Cypriniformes)占比最高,达69.99%。与秦淮河历史形态学监测数据相比,环境DNA宏条形码技术在...  相似文献   

8.
This paper is an inquiry into the circumstances under which the voluntary provision of environmental public goods might be sensible from a firm's point of view. If environmental externalities were the only departure from the economic assumptions of perfect competition, and if no firms had preferential access to superior (low-cost) stocks of natural resources, firms that volunteered to internalize costs could not survive. But because externalities coexist with other departures from the competitive paradigm, such as asymmetric information and oligopoly competition, firms may find it in their shareholders' interests to provide environmental public goods to a greater degree than required by law. A number of firms, especially in Europe and North America, assert that they are pursuing "beyond-compliance" environmental policies. From the perspective of a firm's shareholders, it makes sense to pursue such policies if they increase the firm's expected value or if they appropriately manage business risk.
This paper discusses economically rational explanations for such policies. It analyzes the ways in which a firm's chances of financial success in pursuing any one of them are influenced by the firm's market position and organizational capabilities and by the basic structure of the industry in which it competes.  相似文献   

9.
Although previous studies point to much (untapped) potential for energy efficiency enhancement in industry, empirical research that adapts findings of environmental control to the context of energy management remains widely neglected. Specifically, previous environmental research suggests that the implementation of energy management control systems (EnMCS) could be an effective lever for companies to enhance their production systems and operations toward energy efficiency. Yet, empirical evidence for this theoretical proposition is rather missing; thus, debate continues regarding whether the high investments to set up a comprehensive EnMCS pay off in the long run. Based on a sample of 236 German manufacturing companies, this study combines primary data that capture the configuration of EnMCS with secondary data that were used to calculate energy efficiency. The results provide evidence that the extent of EnMCS implementation positively relates to firms’ energy efficiency. Findings from additional moderation analysis suggest that companies might enhance the relationship of EnMCS and energy efficiency performance by establishing a full‐time energy manager or by using external energy consulting support.  相似文献   

10.
This debate series paper argues that the scientific and socio-economic dimensions of environmental problems are inherently inseparable. The author proposes that understanding this inseparability is the foundation of successful environmental problem-solving, and a prerequisite to the effective use of formal decision-making tools.  相似文献   

11.
A gold rush is currently going on in microbial ecology, which is powered by the possibility to determine the full complexity of microbial communities through next‐generation sequencing. Accordingly, enormous efforts are underway to describe microbiomes worldwide, in humans, animals, plants, soil, air and the ocean. While much can be learned from these studies, only experiments will finally unravel mechanisms. One of the key questions is how a microbial community is assembled from a pool of bacteria in the environment, and how it responds to change – be it the increase in CO2 concentration in the ocean, or antibiotic treatment of the gut microbiome. The study by Zhang et al. ( 2016 ) in this issue is one of the very few that approaches this problem experimentally in the natural environment. The authors selected a habitat which is both extremely interesting and difficult to access. They studied the Thuwal Seep in the Red Sea at 850 m depth and used a remotely operated vehicle (ROV) to place a steel frame carrying substrata for biofilm growth into the brine pool and into the adjacent normal bottom water (NBW). Biofilms were allowed to develop for 3 days, and then those that had been growing in the brine pool were transported to normal bottom water and stayed there for another 3 days, and vice versa. The ‘switched’ biofilms were then compared with their source communities by metagenome sequencing. Strikingly, both ‘switched’ biofilms were now dominated by the same two species. These species were able to cope with conditions in both source ecosystems, as shown by assembly of their genomes and detection of expression of key genes. The biofilms had adapted to environmental change, rather than to brine pools or NBW. The study shows both the resilience and adaptability of biofilm communities and has implications for microbial ecology in general and even for therapeutic approaches such as transplantation of faecal microbiomes.  相似文献   

12.
Investigating the biological mechanisms linking environmental variability to fish production systems requires the disentangling of the interactions between habitat, environmental adaptation and fitness. Since the number of environmental variables and regulatory processes is large, straightening out the environmental influences on fish performance is intractable unless the mechanistic analysis of the 'fish-milieu' system is preceded by an understanding of the properties of that system. While revisiting the key points in our currently poorly integrated understanding of fish ecophysiology, we have highlighted the explanatory potential contained within Fry's (Fry 1947 Univ. Toronto Stud. Biol. Ser. 55, 1-62) concept of metabolic scope and categorization of environmental factors. These two notions constitute a pair of powerful tools for conducting an external (at the emerging property level) analysis of the environmental influences on fish, as well as an internal (mechanistic) examination of the behavioural, morphological and physiological processes involved. Using examples from our own and others work, we have tried to demonstrate that Fry's framework represents a valuable conceptual basis leading to a broad range of testable ecophysiological hypotheses.  相似文献   

13.
贾玉秋  唐立娜 《生态学报》2019,39(8):2986-2994
中国城市需要更为紧凑的空间形态,但是城市空间紧凑性的环境效应并不十分清晰。采集城市管网设施指标、城市道路、交通设施指标、生态协同指标等建立环境因子指标集,选择标准化紧凑度指数NCI、标准化离散度指数NDIS、最大斑块面积指数LPI、景观形状指数LSI、平均形状指数SHAPE_MEAN、周长-面积分形维数PAFRAC等形态指标,运用统计分析的方法探索中国146座城市的空间形态的单因子环境效应、综合环境效应及环境效应的差异性。研究结果表明:(1)人均城市道路面积、供水管密度、排水管密度、万人拥有公交车辆、万人拥有出租车辆、人均公园绿地面积等环境因子与城市空间形态密切相关。城市紧凑度越高,城市管网系统密度越低,公共交通设施越少,人均公园绿地面积越少。城市形状越复杂,城市管网系统密度越高,公共交通投入越大,人均公园绿地面积越大。(2)综合环境因子与LSI呈中等强度的正相关(r=0.43,P0.01)。城市空间形状越复杂,城市资源环境相关设施总体投入越多。(3)在不同的紧凑及形状复杂性水平下,万人拥有公交车辆、万人拥有出租车辆、供水管道密度及综合环境因子的显著性差异再次表明城市越紧凑,交通越发达;城市形状越复杂,环境投入越多。本文研究证明了城市空间形态越紧凑、资源越是节约,紧凑型城市空间形态能够用于中国城市建设。  相似文献   

14.
The nutrient distribution in relation to environmental characteristics of the Saronikos Gulf was studied at two stations for the period 1973–1976. The distribution of measured values and their spatiotemporal variations were compared with previous data for the same area. Winter convection resulted in a very weak gradient of temperature, salinity, oxygen and nutrients. Stratification started to develop in May and persisted. for about six months. Little seasonal variation of nutrients appeared to occur, with higher values generally in winter. It was found that the station in the vicinity of the outfall contained more phosphate and ammonia than the station in the source water. Their levels of nutrients were similar in both years, except in the case of phosphate and nitrite, which were double at the station near the outfall in 1975. Of the nutrients controlling productivity in the photic layer of the examined stations in the Saronikos Gulf, phosphate had a stronger limiting effect on plant growth than inorganic nitrogen.  相似文献   

15.
16.
海草生态学研究进展   总被引:12,自引:3,他引:9  
韩秋影  施平 《生态学报》2008,28(11):5561-5570
海草床生态系统是生物圈中最具生产力的水生生态系统之一,具有重要的生态系统服务功能。作者根据海草生态学及相关领域的最新研究进展,对世界范围内海草床的空间分布、海草床的生态系统服务功能以及外界因素对海草床的影响等研究进展进行了综述。海草床生态系统服务功能主要包括净化水质、护堤减灾、提供栖息地和生态系统营养循环等。对海草床影响较大的外界环境因素包括盐度、温度、营养盐、光照、其他动物摄食、人类活动和气候变化等。海草普查、海草生态功能研究,影响海草床的主要环境因素,海草修复研究等将是我国海草研究的主要方向。  相似文献   

17.
Summary Surveying the chemical pollution status of a given area is increasingly becoming the task of biological indicators, ie animal and plant organisms capable of providing us with the necessary data. For example, in the wake of certain contaminations, they may increase or decrease in number, vary population proportions in relation to given traits, become vectors of certain toxic molecules or heavy metals, or accumulate them in their bodies or in their «products». The advantage of bioindicators over chemical or physical detectors is their ability to supply extensive — both spatially and temporally —rather than limited and instantaneous data, thus making such information more representative. In many instances the bioindicator takes samples for us-a service that is undoubtedly valuable even though it must be linked to a sound knowledge of the organism's ethogram and biology so as to arrive at a scientifically legitimate interpretation of the data provided.  相似文献   

18.
An attempt was made to socialize unrelated and unfamiliar adult rhesus monkey females that had lived in single cages for more than one year. Partners first were given the opportunity for noncontact familiarization in partitioned double cages. They were then transferred into an ordinary double cage. Clear-cut rank relationships were evident within the first 90 minutes of pair formation in 94% (17/18) of dyads tested. Only 28% (5/18) of pairs resorted to fighting (in no case with infliction of serious injury), while 50% (9/18) engaged in social grooming or hugging during this initial phase of pair formation. Eighty-three percent (15/18) of pairs were compatible, with none of the partners showing signs of depression and none inflicting serious injury on the other. Seventeen percent (3/18) of pairs were incompatible (two cases of depression, one serious tail injury) and were separated. It was concluded that the barren environment of singly caged rhesus monkey females can be enriched with little risk by carefully making them compatible companions.  相似文献   

19.
20.
Population dynamics are typically temporally autocorrelated: population sizes are positively or negatively correlated with past population sizes. Previous studies have found that positive temporal autocorrelation increases the risk of extinction due to ‘inertia’ that prolongs downward fluctuations in population size. However, temporal autocorrelation has not yet been analyzed at the level of life cycle transitions. We developed an R package, colorednoise, which creates stochastic matrix population projections with distinct temporal autocorrelation values for each matrix element. We used it to analyze long-term demographic data on 25 populations from the COMADRE and COMPADRE databases and simulate their stochastic dynamics. We found a broad range of temporal autocorrelation across species, populations and life cycle stages. The number of stage-classes in the matrix strongly affected the temporal autocorrelation of the growth rate. In the plant populations, reproduction transitions had more negative temporal autocorrelation than survival transitions, and matrices dominated by positive temporal autocorrelation had higher extinction risk, while in animal populations transition type was not associated with noise color. Our results indicate that temporal autocorrelation varies across life cycle transitions, even among populations of the same species. We present the colorednoise package for researchers to analyze the temporal autocorrelation of structured demographic rates.  相似文献   

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