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541.
This article analyzes the effects of increasing urbanization on open space preserves within the metropolitan area of Phoenix, Arizona, USA. Time series analysis is used in 10-year increments over 40 years to study urban landscape change. Three landscape metrics—(1) matrix utility (measures intensity of adjacent land uses), (2) isolation (measures distances to other open space patches), and (3) connectivity (measures physical links to other open space patches and corridors)—are used to assess changes in landscape patterns and serve as indicators of urban ecological integrity of the open space preserves. Results show that in the case of both open space preserves, general decline in indicators of urban ecological integrity was evident. The matrix utility analysis demonstrated that increasing intensity of land uses adjacent to preserve is likely to increase edge effects, reducing the habitat value of interior or core habitat areas. Isolation analysis showed that both preserves have experienced increasing isolation from other open space elements over time. Also, connectivity analysis indicated that terrestrial connections to other open space elements have also deteriorated. Conclusions of this research demonstrate that while preservation of natural areas as open space is important in an urban context, intense development of surrounding areas reduces the urban ecological integrity significantly.  相似文献   
542.
孙君  王志峰 《环境与发展》2020,(4):27-27,29
通过Quick Bird、ZY-3商业卫星影像遥感解译提取台雄水库周围区域2008年、2018年共2期的土地利用数据,基于叠图法、景观指数法分析了水库建设前后土地利用空间分布格局、变化特征等。主要结论如下:台雄水库采取了有效的植被恢复措施,工程建设对自然植被尤其是森林植被的影响有限,工程建设和运行基本未改变生态系统总体异质性,对区域生态体系的阻抗稳定性影响不大。  相似文献   
543.
Stakeholders’ nonmaterial desires, needs, and values often critically influence the success of conservation projects. These considerations are challenging to articulate and characterize, resulting in their limited uptake in management and policy. We devised an interview protocol designed to enhance understanding of cultural ecosystem services (CES). The protocol begins with discussion of ecosystem‐related activities (e.g., recreation, hunting) and management and then addresses CES, prompting for values encompassing concepts identified in the Millennium Ecosystem Assessment (2005) and explored in other CES research. We piloted the protocol in Hawaii and British Columbia. In each location, we interviewed 30 individuals from diverse backgrounds. We analyzed results from the 2 locations to determine the effectiveness of the interview protocol in elucidating nonmaterial values. The qualitative and spatial components of the protocol helped characterize cultural, social, and ethical values associated with ecosystems in multiple ways. Maps and situational, or vignette‐like, questions helped respondents articulate difficult‐to‐discuss values. Open‐ended prompts allowed respondents to express a diversity of ecosystem‐related values and proved sufficiently flexible for interviewees to communicate values for which the protocol did not explicitly probe. Finally, the results suggest that certain values, those mentioned frequently throughout the interview, are particularly salient for particular populations. The protocol can provide efficient, contextual, and place‐based data on the importance of particular ecosystem attributes for human well‐being. Qualitative data are complementary to quantitative and spatial assessments in the comprehensive representation of people's values pertaining to ecosystems, and this protocol may assist in incorporating values frequently overlooked in decision making processes.  相似文献   
544.
That at least some aspects of nature possess intrinsic value is considered by some an axiom of conservation. Others consider nature's intrinsic value superfluous or anathema. This range of views among mainstream conservation professionals potentially threatens the foundation of conservation. One challenge in resolving this disparity is that disparaging portrayals of nature's intrinsic value appear rooted in misconceptions and unfounded presumptions about what it means to acknowledge nature's intrinsic value. That acknowledgment has been characterized as vacuous, misanthropic, of little practical consequence to conservation, adequately accommodated by economic valuation, and not widely accepted in society. We reviewed the philosophical basis for nature's intrinsic value and the implications for acknowledging that value. Our analysis is rooted to the notion that when something possesses intrinsic value it deserves to be treated with respect for what it is, with concern for its welfare or in a just manner. From this basis, one can only conclude that nature's intrinsic value is not a vacuous concept or adequately accommodated by economic valuation. Acknowledging nature's intrinsic value is not misanthropic because concern for nature's welfare (aside from its influence on human welfare) does not in any way preclude also being concerned for human welfare. The practical import of acknowledging nature's intrinsic value rises from recognizing all the objects of conservation concern (e.g., many endangered species) that offer little benefit to human welfare. Sociological and cultural evidence indicates the belief that at least some elements of nature possess intrinsic value is widespread in society. Our reasoning suggests the appropriateness of rejecting the assertion that nature's intrinsic value is anathema to conservation and accepting its role as an axiom. Evaluar si el Valor Intrínseco de la Naturaleza es un Axioma o un Anatema para la Conservación  相似文献   
545.
Key Elements of Landscape Pattern Measures   总被引:9,自引:0,他引:9  
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546.
Place branding strategies play a significant role in the professional composition of landscape imagery, including the depiction of “natural” landscapes. In this paper, Brand Blue Mountains, a brand currently implemented in the Blue Mountains region (Australia), is discursively analyzed. The brand sets out an all-encompassing “Vision” defining the identity, values and personality of the World Heritage listed Blue Mountains landscape, summarized in the tagline Elevate Your Senses. This “vision” is visually translated into a strictly coordinated and copyrighted suite of logos, graphic design, color, fonts and various photographic styles. Analysis reveals that the degree of control that place brand strategists seek to exert over the visual expression of landscape identity is significant. A highly selective narrative of positive nature-based sensory experience is constructed through the holistic application of contemporary visual media. The brands' communications strategy naturalizes and reinforces a particular market-friendly version of place. The framework that brands set for the representation of landscapes overall amounts to an exercise in calculated aesthetics, whereby the form and content of landscape images of various kinds is measured to achieve the greatest market differentiation and impact which technologies allow. The result of this calculated aesthetic system, with its taglines, saturated color, careful composition and magazine-format brevity, is a reduction in the complexity of landscape representations and a perpetuation of nature stereotypes.  相似文献   
547.
In this paper an overview is presented of the landscape development of the low-lying parts of The Netherlands. It is shown that water has played an important role in this development. Since prehistoric times, but especially since about 800 AD, man has gradually occupied the low lands along the sea and the main rivers. Through these settlements a chain of actions and reactions of man and his physical environment was set into motion. This chain of events is briefly outlined. It is stated and also illustrated that not only the characteristics of the landscape of the western part of The Netherlands, but also the organization of the Dutch society has been influenced strongly by manÕs need to cope with the omnipresence of water and the threats and opportunities posed by that. It is concluded that the outlined events can only be understood properly if interdisciplinary research takes a more prominent role than it does now.  相似文献   
548.
An association has been reported between “low” maternal serum alpha-fetoprotein (MSAFP) and fetal chromosome abnormalities, notably Down syndrome. We suggest the predictive value be used for genetic counselling when a “low” MSAFP is found, and present an illustrative risk table. It can also be seen that normal MSAFP in a woman may lower her age-related risks below that previously defined as “high risk”. However, until good estimates of sensitivity and specificity are available from prospective, population based studies, patients should be told that any risk estimates are rough approximations. When good estimates are available, use of age risks alone may become obsolete.  相似文献   
549.
深圳市土地利用变化对生态服务功能的影响   总被引:8,自引:1,他引:8  
选择深圳市为研究区域,基于1996、2000和2004年的土地利用类型图估算了深圳市生态服务价值,探讨了土地利用对生态服务功能的影响。结果表明:1996年深圳市生态系统服务总价值为277597×104元,2000年为291141×104元,2004年为254466×104元。从1996到2004年生态系统服务价值共减少了23131×104元,其中湿地和林地面积的减少是其主要原因。在各种土地利用类型中,林地、水体、湿地、园地产生的价值之和超过了总价值的90%。在各项服务功能中,水源涵养产生的价值最大,其次是废物处理,两者之和约占总价值的40%。从空间上来看,服务价值较高的地区主要分布在深圳市的东南和西南部,而服务价值较低的区域主要以中部为中心向周围扩散。  相似文献   
550.
在分析借鉴国外污染场地管理框架体系的基础上,结合中国近几年在污染场地法律法规及标准建设方面的经验以及各地的管理实践,提出了建立基于风险的中国污染场地管理模式、管理技术程序、层次化的风险评估方法,以及相应的标准体系构想。  相似文献   
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