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1.
Aerial photography has been routinely used for several decades by natural resource scientists and managers to map and monitor the condition of forested landscapes. Recently, along with the emergence of concepts in managing forests as ecosystems, has come a significant shift in emphasis from smaller to larger spatial scales and the widespread use of geographic information systems. These developments have precipitated an increasing need for vegetation information derived from other remote sensing imagery, especially digital data acquired from high-elevation aircraft and satellite platforms. This paper introduces fundamental concepts in digital remote sensing and describes numerous applications of the technology. The intent is to provide a balanced, nontechnical view, discussing the shortcomings, successes, and future potential for digital remote sensing of forested ecosystems.  相似文献   

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In this article, we focus on documented and possible effects of fish stocking in terms of ecosystem services. The increasing use of fish stocking between 1970 and 2000 in the semiurban setting of Stockholm archipelago, Sweden, is used as case study. The objective is to analyze this management practice from an ecosystem perspective, accounting for both the ecological and social context of releasing fish. The results show that enhancements of four native species (Salmo S. trutta, Salmo salar, Stizostedion lucioperca, and Anguilla anguilla) have dominated over new introductions of one nonnative species. (Oncorhynchus mykiss). The major objective has been to increase fish catches for local resource users. Involved stakeholders include three management agencies, one hydropower company, and several local sport fishing associations. Documented effects focus on recapture and production rates. However, our analysis suggests that additional positive or negative effects on biodiversity, food web dynamics, mobile links, or ecological information may also result, with possible consequences for the long-term provision of food, game, and aesthetic values. We conclude that a more adaptive and cooperative management approach could benefit from a deeper analysis of where, when, and what species is released, by whom, which stakeholders that use the fish and those ecosystem services the fish generate, and of the role of formal and informal institutions for monitoring and evaluating the success of releasing fish.  相似文献   

4.
In the United States and around the world, scientists and practitioners have debated the definition and merits of ecosystem management as a new approach to natural resource management. While these debates continue, a growing number of organizations formally have adopted ecosystem management. However, adoption does not necessarily lead to successful implementation, and theories are not always put into practice. In this article, we examine how a leading natural resource agency, the United States Department of Agriculture Forest Service, has translated ecosystem management theory into concrete policy objectives and how successfully these objectives are perceived to be implemented throughout the national forest system. Through document analysis, interviews, and survey responses from 345 Forest Service managers (district rangers, forest supervisors, and regional foresters), we find that the agency has incorporated numerous ecosystem management components into its objectives. Agency managers perceive that the greatest attainment of such objectives is related to collaborative stewardship and integration of scientific information, areas in which the organization has considerable prior experience. The objectives perceived to be least attained are adaptive management and integration of social and economic information, areas requiring substantial new resources and a knowledge base not traditionally emphasized by natural resource managers. Overall, success in implementing ecosystem management objectives is linked to committed forest managers.  相似文献   

5.
This paper addresses questions of affective responses of residents of rural Arizona to changes in proximate community and riparian landscapes and the congruence of their perceptions of change with physical measures of change in those landscapes. Based on findings and concepts from previous studies, perceptions of change were assessed using a mail survey. Physical measures of land use and vegetation change were obtained from aerial photography for two points in time spanning approximately 13 years and were analyzed using a geographic information system. Significant differences were found in perceptions of change in the community and riparian landscapes. In contrast with previous findings, a majority of respondents found the changes as either improving or having no effect on landscape quality. Those who were more frequent users of the riparian landscape tended to be more aware of changes in it. The findings also suggest challenges for planners and resource managers working in rural areas adjacent to riparian landscapes.  相似文献   

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夏文汇 《四川环境》1995,14(1):28-31
本文运用生态经济系统思想有计划,有步骤地解决水环境问题,针对当前城市水质污染的状况和趋势,找出城市水污染的主要原因,并对城市水环境污染进行经济分析及采取的经济对策,根据城市污水总量污染趋势预测,提出了防治措施,同时,在解决水环境问题时,重视环境效益,经济效益和社会效益的统一。  相似文献   

8.
The human population is rising and the availability of terrestrial land and its resources are finite and, perhaps, not sufficient to deliver enough food, energy, materials and space. Thus, it is important to (further) explore and exploit the marine environment which covers no less than 71% of the earth's surface. The marine environment is very complex but can roughty be divided into two systems: natural (e.g. wild fishing) and human-made (e.g. artificial islands). In this study, characterization factors (CF) for natural and human-made marine systems were calculated in order to be able to assess the environmental impact of occupying marine surfaces, which was not possible so far in life cycle assessment. When accounting for natural resources while occupying one of these systems, it is important to consider the primary resources that are actually deprived from nature, which differs between the natural and human-made marine systems.In natural systems, the extracted biomass was accounted for through its exergy content, which is the maximum quantity of work that the system can execute in its environment. Reference flows for marine fish, seaweeds, crustaceans and mollusks were proposed and their correlated CF was calculated. For human-made systems, the deprived land resource is, in fact, the occupied area of the marine surface. Based on potential marine net primary production data (NPP), exergy based spatial and temporal CFs for ocean areal occupation were calculated. This approach was included in the Cumulative Exergy Extraction from the Natural Environment (CEENE) method which makes it the first life cycle impact assessment (LCIA) method capable of analyzing the environmental impact (and more specific the resource footprint) of marine areal occupation. Furthermore, the methodology was applied to two case studies: comparing resource consumption of on- and offshore oil production, and fish and soybean meal production for fish feed applications.  相似文献   

9.
Jobs and the environment: An overview   总被引:2,自引:0,他引:2  
This paper provides an overview of economic research on the relationship between environmental protection and employment. The paper addresses, first, the impact of existing regulation on overall employment rates, shutdowns and layoffs, and regulation-induced capital flight from developed countries. Second, the paper provides a framework for evaluating claims that, over the longer run, environmental protection measures will boost overall employment and provide the foundation for a robust, sustainable economy.  相似文献   

10.
Indicators of ecosystem recovery   总被引:6,自引:0,他引:6  
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In 1988 I published a paper “Electromagnetic fields—a new ecological factor” (Markov 1988). There was no internet and very few cell phones were available. It was not even fear from the hazard of the power lines. However, I want to cite the beginning of this paper: “The contemporary conditions of life put man in dependence of the complex of physical influences on the environment and in the first place—of the electromagnetic fields. The rapid development of science and technology has resulted in the introduction of many new devices and technologies in industry, agriculture, and everyday life. On the other hand, during their phylogenetic and ontogenic development, the living organisms are continuously exposed to the influence of different biotic and abiotic factors. The physical factors are included in the first group, and the entire evolution of life is connected with an adaptation to the action of these factors.” Could I repeat this statement nearly a quarter of century later? Sure, I will. The only difference would be that I will speak not only for electromagnetic fields, but for green-house effects, global warming, volcano eruption, and radiation disasters. I would also discuss the noise and vibration to which people are exposed from early days to the very end of their life traveling with private vehicles or public transport.  相似文献   

13.
Ethanol fuels: Energy security,economics, and the environment   总被引:6,自引:0,他引:6  
Problems of fuel ethanol production have been the subject of numerous reports, including this analysis. The conclusions are that ethanol: does not improve U.S. energy security; is uneconomical; is not a renewable energy source; and increases environmental degradation. Ethanol production is wasteful of energy resources and does not increase energy security. Considerably more energy, much of it high- grade fossil fuels, is required to produce ethanol than is available in the energy output. About 72% more energy is used to produce a gallon of ethanol than the energy in a gallon of ethanol. Ethanol production from corn is not renewable energy. Its production uses more non- renewable fossil energy resources in growing the corn and in the fermentation/distillation process than is produced as ethanol energy. Ethanol produced from corn and other food crops is also an unreliable and therefore a non-secure source of energy, because of the likelihood of uncontrollable climatic fluctuations, particularly droughts which reduce crop yields. The expected priority for corn and other food crops would be for food and feed. Increasing ethanol production would increase degradation of agricultural land and water and pollute the environment. In U.S. corn production, soil erodes some 18- times faster than soil is reformed, and, where irrigated, corn production mines water faster than recharge of aquifers. Increasing the cost of food and diverting human food resources to the costly and inefficient production of ethanol fuel raise major ethical questions. These occur at a time when more food is needed to meet the basic needs of a rapidly growing world population.  相似文献   

14.
The changing status of the global environment, in both developed and developing countries, and our perception of these changes since the convening of the United Nations Conference on the Human Environment in Stockholm in 1972 are reviewed. The present as well as potential future environmental issues facing mankind are discussed under three interrelated broad categories: interrelationship between people, resources, environment and development, rational use of natural resources and new patterns of development and lifestyle.  相似文献   

15.
Multiple ecological tactics, like the ones described here, can be imitated to strongly affect these two components in the construction sector. This article provides an in-depth examination of the literature on biomimicry-based strategies intended to enhance building designs. This analysis is motivated by the rising need for energy legislation to achieve future local goals and provide a framework for use in Panama. These biomimicry-based methods have undergone more review and evaluation, and the incorporation of organism-based design for three of Panama's climate types has been proposed. Therefore, a SWOT analysis assisted in realizing the full potential that biomimicry-based techniques might have in raising the likelihood of satisfying local and international regulatory standards. In order to design constructions using biomimicry, multidisciplinary collaboration is required. This gives a competitive edge for better-trained human resources and expands horizons in the conventional construction industry. Finally, the analysis provided here might act as the preliminary step for the additional technical assessment using numerical and experimental procedures.  相似文献   

16.
Abstract

This article examines results from in-depth interviews conducted with parents of children with asthma living in an urban environment. We examine themes from the in-depth interviews related to participants' perceptions of the influence of their physical environment on their mental and physical health, and the actions that they take in an effort to protect their health within this context. The findings from this study suggest several implications for understanding the interface between the physical environment of urban communities and residents' health, as well as for the policy and practice of risk assessment strategies.  相似文献   

17.
The concern of this paper is with the spatial consequences of development in a given rural setting and the way in which physical planning fits into the revival of a dying rural area, particularly in Third World Countries. It is based on experience derived from Dekinal in Benue State, Nigeria and endeavours to define a rural area by briefly discussing its characteristics and highlighting its problems. It proposes a comprehensive development planning process to induce development based on available resources.  相似文献   

18.
城市生态系统是以人为中心的人工生态系统。城市环境是人类利用和改造环境而创造出来的高度人工化的生存环境,中小城市是区域内经济活动、生产活动、物资能量流通的中心。本文对城市生态系统的特征进行了分析,对如何进行城市生态环境规划进行了探讨。  相似文献   

19.
Environmental personalization and elementary school children's self-esteem   总被引:1,自引:0,他引:1  
Prior research indicates that the physical classroom environment has the potential to affect children's behaviors, academic performance, and cognitive development. However, less is understood about the effect on the socio-emotional development of children. This study investigates the potential role of one aspect of the classroom's physical environment, personalization displays, on children's self-esteem. The study employed a classroom intervention in a quasi-experiment to examine the effects of increasing environmental personalization on children's self-esteem. Thirty-eight kindergarteners and first graders in six classrooms of two elementary schools in a rural community of a north-eastern state were assessed on pretests and post-tests of the Self-Esteem Index (SEI) scale and the Children's Inventory of Self-Esteem (CISE) scale. The findings were mixed but encouraging. On both measures of self-esteem, there was a significant positive effect of classroom personalization for first graders. However, for kindergarteners there was a significant positive effect for only one measure, the CISE. Although there are limitations with the study design, the findings suggest that young children's self-esteem may be influenced and enhanced by specific aspects of the classroom's physical environment.  相似文献   

20.
This article examines results from in-depth interviews conducted with parents of children with asthma living in an urban environment. We examine themes from the in-depth interviews related to participants' perceptions of the influence of their physical environment on their mental and physical health, and the actions that they take in an effort to protect their health within this context. The findings from this study suggest several implications for understanding the interface between the physical environment of urban communities and residents' health, as well as for the policy and practice of risk assessment strategies.  相似文献   

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