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621.
Indicators of perceived naturalness as drivers of landscape preference   总被引:3,自引:2,他引:1  
The concept of naturalness is one of the more studied concepts in landscape preference research and describes how close a landscape is to a perceived natural state. In this study we explored the relationship between landscape preference and three landscape indicators of naturalness (level of succession, number of woodland patches and shape index of edges). We used computer-generated visualisations of a hypothetical landscape containing pasture and broadleaved woodland. In the landscape simulations we altered the values of the naturalness indicators between the levels of low, medium and high, creating 27 different visualisations. The survey was distributed as an on-line survey in seven different languages and obtained 703 respondents. The study showed a strong relationship with preference for both the level of succession and number of woodland patches, and a weaker relationship with shape index of edges. The two demographic factors which were shown to contribute most to the formation of preference were gender and having a landscape related profession. The results suggest that the selected indicators are more important drivers of preference than demographic factors.  相似文献   
622.
Indicators are commonly used as tools to identify and highlight socio‐economic and ecological trends and to assess progress towards sustainability. Different quality criteria can be considered for indicators. This paper focuses on the timeliness of indicators used in the evaluation of sustainable development strategies. The analysis is based on indicators included in four assessment reports of the sustainable development strategy of the European Union and three assessment reports of the national strategy of Finland. Furthermore, a web‐based national level indicator portal is analysed. The results show that the timeliness of indicators has generally not improved during the past decade and that indicators used in strategy evaluations have a time lag of approximately two years. It is suggested that more attention should be given to efforts to improve the timeliness of indicators in order to increase the effectiveness of the evaluations. More generally, it is suggested that greater emphasis should be put on the empirical research on actual use of indicators.  相似文献   
623.
The paper presents a quantitative engineering approach to analysis of total environment allowing for simultaneous consideration of a theoretically infinite number of quality indicators and physiological requirements. It discusses theory and fundamentals of a two-dimensional space and time function solution concerning a small estuarine-type environment. A three dimensional solution is indicated. Input data may range from reconnaissance-type to the outputs of mathematical transport models. Applications are discussed with respect to environmental quality problems, availability of suitable data, and some areas of research where results could find immediate application.  相似文献   
624.
ABSTRACT: A brief review of environmental assessment methods is presented as an introduction to a study of environmental management problems in a coastal area of southern Louisiana. The assessment method used in the study is called suitability analysis and involves the use of matrices. The matrix approach is simply a convenient method for organizing all factors representing environmental concerns in a region. The matrices proved to be very useful in defining the present state of an environmental regime and in maintaining an inventory of regional features and potential impacts. The method is described in detail and illustrated by evaluating the potential impacts of a major pipeline construction job in the area. Of major concern is the potential impact on the water resources of the region. Disruption to the natural drainage could be detremental, and affect the suitability of available water for a given use. Limitations of the method are discussed and potential areas for improvement and research are noted. Coupled with an economic assessment, the suitability analysis method should prove beneficial for selecting development sites for industries, residential areas, and other construction activities.  相似文献   
625.
Morgan R 《Disasters》1985,9(1):44-50
This article describes the indicators and data sources used by the Botswana Drought Early Warning System formally established in early 1984, the main uses of the indicators in the assessment of drought conditions and the design of relief programmes are outlined. Limitations of the sources of data available are discussed, as is the feasibility of adding some possible further indicators. In conclusion, the importance of a functioning Early Warning System in a country highly susceptible to repeated droughts is stressed, in the context of die current effort to elaborate a comprehensive National Food Strategy and to establish a Regional Early Warning System for Southern Africa.  相似文献   
626.
基于3S技术的综合集成的数字流域水资源环境监测评价可以获取传统监测手段所无法取得的更多信息,已成为目前国内外水资源环境监测评价的重要技术手段。本文提出了基于3S技术与传统监测手段综合集成的数字流域水资源环境监测评价信息处理基本模式,对数字流域水资源环境监测评价指标体系建立的理论基础、基本原则进行了探讨,以西北干旱区内陆河流域石羊河为例,建立了石羊河流域水资源环境监测评价指标体系。在水资源环境监测评价信息系统的开发中,提出指标库管理的思想,基于COM技术,用VC++6.0为开发工具,初步实现了石羊河流域水资源环境监测评价信息系统。  相似文献   
627.
高效液相色谱法分离和测定甲醛和苯酚   总被引:2,自引:0,他引:2  
本文讨论了高效液相色谱分离和测定甲醛和苯酚的条件,并对酚醛树脂生产废水进行了实际测定,结果令人满意。  相似文献   
628.
Changes in marine ecosystems can be manifested in many different ways, on different temporal and spatial scales. Seabirds are top consumers in marine foodwebs and offer opportunities to detect and assess the biological effects of changes in physical parameters (sea-surface temperature [SST], salinity, depth of thermocline etc.) of the marine ecosystem. We compare six-eight years' of data on the biology (diet, and breeding success) of four species of seabird (arctic tern Sterna paradisaeaand common tern S. hirundo, which feed at the sea surface; and Atlantic puffin Fratercula arctica and razorbill Alca torda, which dive 30–60 m for their prey) breeding on Machias Seal Island (MSI) in the Bay of Fundy with both our own meteorological and oceanographic measurements, and with standard measurements from conventional sources. These are compared with fisheries data on changes in the main prey of all the seabirds concerned (juvenile or 0-group herring Clupea harengus) which are the most direct link between the seabirds and the physical properties of the marine system. We explore relationships between seabird productivity and diet, and other aspects of both herring biology (larval surveys, and fat content) and oceanography (SST data from the island, and remotely sensed data from the entrance to the Bay of Fundy). Timing of laying by puffins followed SST variation at neither the local (MSI) nor regional scales, but at the scale of the North Atlantic, following the trend of populations breeding off northern Norway. The proportion of herring in the diet of terns over 6 years varied inversely with herring larval abundance the previous fall; this relationship was not statistically significant in the puffin and razorbill. A major new finding is the considerable (50%) inter-annual variation in the energy density (fat content) of juvenile herring that are the main seabird prey; breeding success of both species of tern varied in parallel with the energy density of juvenile herring in the diet until the last two years of the study, when sandlance (Ammodytes sp.) and euphausid shrimp predominated in the diet. Our long-term research approach combines traditional population monitoring (of numbers of breeding birds) with demographic, behavioural and environmental monitoring, to provide new understanding of the marine ecosystem as well as of seabirds.  相似文献   
629.
The Great Lakes Water Quality Agreement stipulates that the Governments of Canada and the United States are responsible for restoring and maintaining the chemical, physical and biological integrity of the waters of the Great Lakes Basin Ecosystem. Due to varying mandates and areas of expertise, monitoring to assess progress towards this objective is conducted by a multitude of Canadian and U.S. federal and provincial/state agencies, in cooperation with academia and regional authorities. This paper highlights selected long-term monitoring programs and discusses a number of documented ecological changes that indicate the present state of the open and nearshore waters of the Great Lakes.  相似文献   
630.
This paper considers the use of meiofauna (benthic metazoa 45 to 500 m in size) as biological indicators for monitoring marine environmental health. To date, this abundant and ubiquitous group of invertebrates has been largely neglected in applied sampling programmes; instead, emphasis has been placed upon more conspicuous biological components such as seagrass, macrofauna and epiphytes. In an attempt to redress this balance, this paper sets out three objectives: (1) to explain the reasons for selecting biological response indicators from across the whole spectrum of phylogenetic organisation, (2) to summarise those aspects of meiofaunal life-history and demography that render this group suitable for monitoring anthropogenic pollution and disturbance, (3) to suggest how to optimise the inclusion of meiofauna in monitoring programmes so that they provide maximum information for management purposes. To achieve these objectives the environmental impact assessment framework of Ward and Jacoby (1992) is adopted as a matrix into which the relevant components of meiofaunal ecology are fitted. Using this matrix, meiofauna are shown to have advantages that include their sessile habit, high species diversity, short generation time, direct benthic development and ubiquitous distribution. Disadvantages include their small size, high level of spatial and temporal variability, the potential cost of sample processing and the limited taxonomic literature accessible to non-specialist workers. The paper concludes with a discussion of sampling strategies and methods of analysis that may be used to efficiently incorporate meiofauna as biological response indices into environmental monitoring. Emphasis is placed on cost-effective techniques such as taxonomic minimalism.  相似文献   
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