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1.
Land use and cover changes have been identified as a major factor contributing to shape landscape structure and biodiversity patterns, particulary in areas with a long history of human occupation and habitat fragmentation, such as the Mediterranean landscapes. However, the existing studies on landscape change indicators for Mediterranean areas have mostly focused in Europe, while for other Mediterranean zones, and especially for South America, there is a serious lack of knowledge concerning the impact of landscape dynamics on ecological processes. Further research on this topic is urgently needed, given the high biodiversity levels and the rapidly increasing rates of human modification in the Mediterranean landscapes of South America. For this purpose, we investigated the dynamics of a landscape in the semiarid region of the Mediterranean zone of Chile, and measured the effect of those dynamics on functional connectivity, during a period of about four decades (1975–2011). Landscape connectivity indicators were extracted from a series of Landsat images. The Equivalent Connnected Area index (ECA) was used as indicator of connectivity trends, and was evaluated for three representative distances of seed dispersal in the study area (150 m, 500 m and 1000 m). In addition, the patches that most contribute to maintain the present connectivity, and their roles as connectivity providers, were identified through a set of commensurable indicators: betweenness centrality and the fractions (intra, flux connector) of the Integral Index of Connectivity. We found that these indicators were useful to detect and summarize a number of previously unreported trends in these Mediterranean landscapes. First, population growth and economic development were compatible with an increase in functional connectivity for forest habitats, mainly because the abandonment of marginal agricultural lands and their subsequent conversion to espinals (Acacia caven) triggered vegetation succession towards secondary forests. Second, increased forest connectivity was not associated to a decrease in the characteristic heterogeneity of Mediterranean landscapes. Third, many patches of espinal, despite being commonly regarded as of poor conservation value, were crucial to promote connectivity by acting as stepping stones among other patches with higher habitat quality. The approach here presented provides a combined assessment of landscape structure, function and change that should be valuable and applicable to deliver operational indicators in dynamic landscapes in South America and other Mediterranean regions.  相似文献   

2.
Evaluation of achievement of set targets is a necessary step in landscape planning in order to learn from the past, reassess implemented measures and enhance trust in public managers and institutions. Though it is commonly accepted that indicators play a major role in such evaluations, so far no accepted framework for evaluating planning outcomes exists. Furthermore, the selection of appropriate indicators and reference values to effectively assess conditions of landscapes and determine whether observed developments can be considered positive or negative remains challenging. Our study contributes to much-needed research on this topic with a proposed evaluation framework built on goals, indicators and reference values. We analyzed the landscape section of eight Swiss cantonal comprehensive plans to specifically address (1) whether currently tracked indicators suffice to evaluate landscape-planning goals; (2) what a minimal set of landscape indicators for regional planning might look like; and (3) how the ratified value approach could be operationalized to develop reference values for landscape indicators. All eight plans have a similar hierarchical goal system with six major landscape goals, up to 18 themes and 21–33 subordinate goals. The studied cantons track from 29 to 84 indicators. We found a considerable imbalance in the ratio between subordinate goals and indicators, with comparatively few indicators being tracked to assess visual and recreational landscape quality. Our proposed minimal indicator set is well balanced since it lists 5–7 indicators for each theme. The general procedure for modeling reference values is based on the assumption that the protection status of a landscape is a proxy for high societal appreciation of a place. Consequently, indicator values for these areas would reflect reference values (ratified values). We illustrate the procedure with the exemplary indicator impervious surface. The proposed indicators and maps are powerful tools for outcome evaluation and also facilitate benchmarking, i.e. interregional comparisons of landscape qualities, which could be very useful for landscape planning in Europe.  相似文献   

3.
Education is one of the multiple services that ecosystems and landscapes provide to societies. Despite its importance to formal and informal learning and nature-based, cognitive tourism, it is hardly taken into account in the various quantification approaches of ecosystem services. The article provides an overview of landscape educational values and the educational ecosystem service. Here, the forms of the use of landscape educational values have been summarised and the indicators for the quantification of the educational ecosystem service proposed in the literature reviewed. The criteria for the evaluation of the educational values of landscape were acquired from the literature and discussed. In order to obtain more practical viewpoints on those criteria, an exploratory survey with young experts (n = 37) from two universities of environmental sciences was conducted. Within this step, the expert method for the evaluation of the educational values of landscapes was applied. However, the results show an extremely high level of subjectivity and dependence on personal experience regarding outdoor environmental education. Nonetheless, the article can contribute to acquiring knowledge in cultural ecosystem service assessment and the application of this concept, especially in terms of the criteria and indicators which can be potentially used for the assessments.  相似文献   

4.
5.
邓可  宋峰  史艳慧 《生物信息学》2018,25(11):96-99
历史性城市景观是遗产保护领域近十几年来提出的新概念,关于其学术意义的讨论也层出不穷。从文化景观所蕴含的时空过程的学术视角着眼,分别梳理了文化景观的学术脉络与遗产领域中的文化景观和历史性城市景观的实践发展历程,指出历史性城市景观并没有超出文化景观的学术范畴,而遗产领域当前面临的很多问题都与对文化景观学术内涵的认知缺陷有关。只有充分借鉴和吸收文化景观的学术成果,才能真正有效地应对世界遗产实践过程中复杂变化的人地关系等挑战。  相似文献   

6.
7.
Despite the fact that many ecological landscape indicators have been applied so far, it is challenging to develop an indicator(s) which is easy and cheap to assess while at the same time reflecting the complexity of an ecosystem. The author aimed at the development of such an indicator: the Indicator of Ecological Landscape Quality (IELQ) which ranged from 0 to 2. This is based on the use of surrogate measures of assessing ecological quality (EQ) and a GIS approach. The employed measures include: landscape diversity, the degree of ecological significance of land cover forms, and the character of linear landscape structures. To verify the validity of the adopted measures, the indicator was calculated for areas under different conservation statuses and adjoining non-protected areas located in eastern Poland, 20 sites in total. The results showed that differences in mean IELQ values between areas under different protection regimes are significant (Tukey: p < 0.01). The highest mean values were obtained for nature reserves (0.86), and the lowest for non-protected areas (0.27). Explanatory factors for EQ included the proportion of natural and anthropogenic land cover forms, and the number of land cover forms. Surprisingly, the correlation between the latter factor and IELQ is negative (−0.704), indicating that the lower the landscape diversity, the higher the ecological values. From the protected area management point of view, the developed indicator proved its usefulness in terms of an assessment of ecological values and indicated changes in values over time.  相似文献   

8.
在探讨生态系统健康概念构架的基础上,寻求对管理景观中的生态系统健康进行整体性评价的合适指标.健康的生态系统不仅在生态学意义上是健康的,并能维持健康的人类群体及有利于社会经济的发展.健康生态系统的一般特征是恢复力、多样性和生产力.建立生态系统健康评价指标的第一步是指标选择原则的确定,根据生态系统健康评价的目的和指标筛选的原则,把生态系统健康指标体系(Ecosystem Health Indicaror,EHI)分为生物物理指标、生态学指标和社会经济指标.  相似文献   

9.
This study investigates the importance of spatial landscape characteristics and habitat management on the condition of calcareous grassland in the North Down Natural Area, Kent UK. We used a digitised map of the study area containing shapefiles of all the habitats including 82 patches of calcareous grassland together with management information for each patch and data on the presence and abundance of a range of calcareous grassland indicator plant species. We defined habitat condition by presence of indicator species and used classification trees to generate models with rules for predicting habitat condition from the landscape spatial characteristics and management information. We also applied the same method to investigate the factors affecting presence or diversity of three ecological groups of positive indicator species and dominance of a negative indicator species. All the models except one showed good classification accuracy and high kappa statistic. Favourable habitat condition was predicted by presence of different types of grazing management, presence of woodland around patches of calcareous grassland and shape complexity. These results indicate that calcareous grassland in favourable condition is management-dependent but also located in less intensively managed landscapes. Unfavourable habitat condition was predicted by threat factors such as lack of management and high incidence of arable or improved grassland around patches of calcareous grassland, indicating nutrient enrichment and habitat degradation. Some of these factors also predicted high diversity of the different ecological species groups. The value of this method for predicting habitat condition and species diversity from baseline ecological data for conservation monitoring at the landscape level is emphasised.  相似文献   

10.
Indicator species (IS) are used to monitor environmental changes, assess the efficacy of management, and provide warning signals for impending ecological shifts. Though widely adopted in recent years by ecologists, conservation biologists, and environmental practitioners, the use of IS has been criticized for several reasons, notably the lack of justification behind the choice of any given indicator. In this review, we assess how ecologists have selected, used, and evaluated the performance of the indicator species. We reviewed all articles published in Ecological Indicators (EI) between January 2001 and December 2014, focusing on the number of indicators used (one or more); common taxa employed; terminology, application, and rationale behind selection criteria; and performance assessment methods. Over the last 14 years, 1914 scientific papers were published in EI, describing studies conducted in 53 countries on six continents; of these, 817 (43%) used biological organisms as indicators. Terms used to describe organisms in IS research included “ecological index”, “environmental index”, “indicator species”, “bioindicator”, and “biomonitor,” but these and other terms often were not clearly defined. Twenty percent of IS publications used only a single species as an indicator; the remainder used groups of species as indicators. Nearly 50% of the taxa used as indicators were animals, 70% of which were invertebrates. The most common applications behind the use of IS were to: monitor ecosystem or environmental health and integrity (42%); assess habitat restoration (18%); and assess effects of pollution and contamination (18%). Indicators were chosen most frequently based on previously cited research (40%), local abundance (5%), ecological significance and/or conservation status (13%), or a combination of two or more of these reasons (25%). Surprisingly, 17% of the reviewed papers cited no clear justification for their choice of indicator. The vast majority (99%) of publications used statistical methods to assess the performance of the selected indicators. This review not only improves our understanding of the current uses and applications of IS, but will also inform practitioners about how to better select and evaluate ecological indicators when conducting future IS research.  相似文献   

11.
生态系统健康评价—概念构架与指标选择   总被引:114,自引:15,他引:99  
在探讨了生态系统健康概念构架的基础上,寻求对管理景观中的生态系统健康进行整体性评价的合适指标,健康的生态系统不仅在生态学意义上是健康的,并能维持健康的人类群体及有利于社会经济的发展,健康生态系统的一般特征是恢复力,多样性和生产力,建立生态系统健康评价指标的第一步是指标选择原则的确定,根据生态系统健康评价的目的和指标筛选的原则,把生态系统健康指标体系(Ecosystem Health Indicator,EHI)分为生物物理指标,生态学指标和社会经济指标。  相似文献   

12.
As European integration increasingly affects pan-European nature conservation, indicators for the assessment of habitats are urgently needed to support ecosystem integrity monitoring as well as the target of halting biodiversity loss by 2010. The Natura 2000 network of protected sites with a strong focus on the protection of habitat types and strict monitoring obligations is now legally binding for all Member States. From a set of indicators that have been proposed for habitat monitoring by the SPIN project (Spatial Indicators for European Nature Conservation) we describe measures of landscape structure and soil function and their potential for the monitoring and management of protected areas and the surrounding landscape. In a case study from Austria, we show that structure-related indicators hold potential for the documentation of local-scale changes on a degraded raised bog Natura 2000 site. In a regional scale case study in northern Germany, we show how landscape metrics relate agricultural statistics, e.g. farm size and livestock density to landscape structure. In a third case study from Slovenia, we show how coarse-scale soil data can be disaggregated to finer scale by integrating topographic information and additional parameters for modelling, and production of soil-related habitat suitability maps. From these case studies we provide an overview of some of the critical issues affecting the selection and application of spatial indicators for nature conservation monitoring tasks. End users of spatial indicators work at different scales and in different biogeographical regions. The indicator selection and application demonstrated in our three case studies reveals the capability to contribute to a more quantitative evidence base for monitoring and management of biodiversity in Europe.  相似文献   

13.
Objective Although practice guidelines for depression screening are evidence based, with their development relying on reviews of controlled studies, their adaptation and use as quality indicators have not been subject to rigorous study. This paper will therefore review the evidence supporting this practice.Methods A rational evaluation was carried out on both controlled studies and other sources of evidence related to the technical, clinical and policy assumptions underlying the use of depression screening guidelines as quality indicators.Results 1) Technical assumptions: depression screening could be used as a quality indicator. Current information technology does not allow accurate determination of who would benefit from being screened, whether they actually were screened, or the optimal percentage that should be screened. 2) Clinical assumptions: depression screening would improve outcomes. The evidence suggests that although depression screening might increase the diagnosis of depression, depressed patients so recognised tend to be less ill, less in need of treatment, or less likely to benefit from treatment, while screening, in the absence of other interventions, does not improve outcomes. 3) Policy assumptions: depression screening should be a focus of quality improvement. However, relative to other preventative measures, depression screening is a low priority. It does not meet usual cost-effectiveness criteria. There are more robust interventions for depression (i.e. collaborative care) that could be a focus of quality improvement efforts.Conclusion Although routine depression screening may be an acceptable practice guideline, its use as a quality measure is not supported.  相似文献   

14.
生态社区评价指标体系研究进展   总被引:5,自引:2,他引:5  
周传斌  戴欣  王如松  黄锦楼 《生态学报》2011,31(16):4749-4759
生态社区建设融合了建筑学、生态学、社会学等多学科原理,充分体现了人与自然和谐的理念,是符合可持续发展理念的社区发展模式。生态社区评价指标体系在一定的一级指标框架下,采用定性或定量的评价指标,评判社区的可持续发展水平。对生态社区的概念和内涵、形成与发展历程、国内外生态社区相关评价指标体系进行总结和归纳,在此基础上综述了生态社区评价指标体系的研究进展,包括评价主体、一级指标框架的构建、二三级指标使用的频度分析及指标权重的确定方法。最后总结分析了生态社区指标体系研究中对外环境关联、动态发展、参与性与适应性等方面的不足,提出将复杂性理论、生命周期分析方法和生态足迹分析引入生态社区评价指标体系的研究,以提高指标体系的系统性、科学性和参与性。  相似文献   

15.
This paper presents a data-flexible indicator framework for analysis of visual landscape character; the VisuLands framework. The theory-based framework encompasses currently used indicators for visual assessment based on four different data sources: land cover data, aerial photographs, landscape photographs and field observations. This paper presents a study applying the VisuLands framework in analysis of landscape change and its effect on visual scale in a landscape in Southeast Sweden. The paper provides a critical assessment of the pros and cons of the approach. It identifies the advantages and disadvantages of using different data sources as well as the applicability and sensitivity of existing indicators in detecting visible landscape change. The results show that while some of the VisuLands indicators are relatively easily applied, others are more complex and demanding in terms of interpretation. The flexibility of the VisuLands framework makes it applicable and user-friendly as it helps meet the requirements and restrictions of the users. The assessment has shown that the different data sources complement each other and that applying indicators using various data sources, when available, will enhance the comprehensiveness of visual landscape assessment. The experience of this study is that the VisuLands framework is a useful tool in landscape analysis, monitoring and planning, which provides a repeatable, systematic and transparent approach with strong links to landscape theory.  相似文献   

16.
在回顾英国景观特征评估体系产生和演化背景的基础上,分析了景观特征等概念,研究了景观特征评估体系在英国法定自然美景区中的应用,并将其特点归纳为价值中立和尺度分级、多样化的景观特征提取、单独分离的决策过程3个方面;同时将LCA景观特征评估体系与我国风景名胜区中广泛应用的风景资源评价体系进行了比较,结合我国风景名胜区发展的现状,提出我国可以在景观遗产价值的评估、景观遗产可持续发展概念的再认识、公众参与制度的进一步完善3个方面借鉴景观特征评估体系的经验。  相似文献   

17.
There is a need to develop non-monetary methods for the assessment of cultural ecosystem services, in order to integrate them into the ES framework in a more balanced way. With this in mind, an adequate and comprehensive indicator base and mapping methods are required to communicate and discuss cultural ecosystem services, for it to be understood holistically. Referring to land use changes as an important driver for ES changes, we demonstrate the analysis of cultural ecosystem services trends, in a retrospective, as a supporting tool to better understand social and natural interactions as drivers behind land use changes, which are reflected in the landscape scene. There are two main outcomes of this study: (1) first, we developed and tested a catalogue of indicators as an approach to evaluate cultural ecosystem services trends at the local scale and (2) we established a mapping method for cultural ecosystem services trends in parallel with land use changes. This we did following the example of the afforestation processes which had taken place since the 19th century in the suburban area of Göttingen (Lower Saxony/Germany), called Hainberg. Our main conclusion is that cultural ecosystem services trends can indicate the reasons and drivers for land use changes that can be beneficial to forest/landscape management issues by means of the restoration of lost services. The proposed assessment method can be integrated into the development of future landscape plans, e.g. by providing information on historical guiding principles.  相似文献   

18.
This paper critically reviews developments in the conceptualization and elaboration of the River Ecosystem Health (REH) concept. Analysis of literature shows there is still no consistent meaning of the central concept Ecosystem Health, resulting in models (i.e. elaborations) that have unclear and insufficient conceptual grounds. Furthermore, a diverse terminology is associated with describing REH, resulting in confusion with other concepts. However, if the concept is to have merit and longevity in the field of river research and management, unambiguous definition of the conceptual meaning and operational domain are required. Therefore a redefinition is proposed, based on identified characteristics of health and derived from considering semantic and conceptual definitions. Based on this definition, REH has merit in a broader context of river system health that considers societal functioning next to ecological functioning. Assessment of health needs integration of measures of multiple, complementary attributes and analysis in a synthesized way. An assessment framework is proposed that assesses REH top-down as well as bottom up by combining indicators of system stress responses (i.e. condition) with indicators identifying the causative stress (i.e. stressor). The scope of REH is covered by using indicators of system activity, metabolism (vigour), resilience, structure and interactions between system components (organization). The variety of stress effects that the system may endure are covered by using biotic, chemical as well as physical stressors. Besides having a unique meaning, the REH metaphor has added value to river management by being able to mobilize scientists, practitioners and publics and seeing relationships at the level of values. It places humans at the centre of the river ecosystem, while seeking to ensure the durability of the ecosystem of which they are an integral part. Optimization of the indicator set, development of aggregation and classification methodologies, and implementation of the concept within differing international frames are considered main aims for future research.  相似文献   

19.
The selection, testing and application of terrestrial insects as bioindicators   总被引:12,自引:0,他引:12  
Although the uses and merits of terrestrial insects as indicators have been extensively discussed, there is a lack of clear definition, goal directedness and hypothesis testing in studies in the field. In an attempt to redress some of these issues and outline an approach for further studies, three categories of terrestrial insect indicators, corresponding to differences in their application, are proposed, i.e. environmental, ecological and biodiversity indicators. The procedures in terrestrial insect bioindicator studies should start with a clear definition of the study objectives and proposed use of the bioindicator, as well as with a consideration of the scale at which the study is to be carried out. Bioindication studies are conducted at a variety of spatial and temporal scales within the context of earth-system processes, but the objectives of the study will largely determine the scale at which it would be optimally conducted. There is a tendency for studies to be conducted below their space-time scaling functions, giving them apparent predictability. The selection of potential indicator taxa or groups is then based on a priori suitability criteria, the identification of predictive relationships between the indicator and environmental variables and, most importantly, the development and testing of hypotheses according to the correlative patterns found. Finally, recommendations for the use of the indicator in monitoring should be made. Although advocating rigorous, long-term protocols to identify indicators may presently be questionable in the face of the urgency with which conservation decisions have to be made, this approach is critical if bioindicators are to be used with any measurable degree of confidence.  相似文献   

20.
The importance of the values underlying different concepts of biodiversity conservation and landscape planning is increasingly recognised, and yet these value judgements of the public and of experts are still poorly understood. Although landscape and conservation management are closely interrelated and measures in one field are likely to have effects on the other, the relationship between biodiversity and conservation values on the one hand, and landscape preferences on the other hand, has been hardly explored so far. This study represents a first attempt to empirically examine this relationship from an integrated perspective, considering philosophical, ecological and economic aspects and using items focused on biodiversity. We used a quantitative survey of the general Swiss population with visualisations of potential landscape developments in the Swiss Alps and items related to biodiversity- and conservation-values. Our research shows that respondents who prefer reforested landscapes tend to be more concerned about the conservation of species, landscapes, and natural processes than people preferring cultural landscapes. Respondents who prefer cultural landscapes are more oriented towards utilitarian values and are overrepresented in mountain areas as compared to the lowlands, thus in areas that are more likely to become the target of conservation measures. Our findings have practical implications for conservation in Switzerland and other mountainous areas, particularly in times of agricultural decline and land abandonment and their associated changes in landscape and biodiversity.  相似文献   

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