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81.
广东内伶仃岛的生物资源及自然保护规划 总被引:1,自引:0,他引:1
广东省内伶仃岛生物资源较为丰富,共有野生维管植物133科379属569种,其中广东新记录种10种;苔藓植物19科34属61种,广东新记录种10种,各类动物有兽类数十种,包括国家珍稀濒危保护动物猕猴(Macac mulatta)等,两栖爬行类30多种,鸟类近110处,昆虫超过447种。 此外,内伶钉岛也是一个较为封闭的生态系统,根据该岛各类生物资源和生态环境特点,宜划分为核心区,旅游-科普区和实验-缓冲区3部分,对各区的特点、性质,以及全岛的发展规划进行了初步探讨。 相似文献
82.
Extended statistical approaches to modelling spatial pattern in biodiversity in northeast New South Wales. II. Community-level modelling 总被引:7,自引:0,他引:7
Simon Ferrier Michael Drielsma Glenn Manion Graham Watson 《Biodiversity and Conservation》2002,11(12):2309-2338
Regional conservation planning can often make more effective use of sparse biological data by linking these data to remotely mapped environmental variables through statistical modelling. While modelling distributions of individual species is the best known and most widely used approach to such modelling, there are many situations in which more information can be extracted from available data by supplementing, or replacing, species-level modelling with modelling of communities or assemblages. This paper provides an overview of approaches to community-level modelling employed in a series of major land-use planning processes in the northeast New South Wales region of Australia, and evaluates how well communities and assemblages derived using these techniques function as surrogates in regional conservation planning. We also outline three new directions that may enhance the effectiveness of community-level modelling by: (1) more closely integrating modelling with traditional ecological mapping (e.g. vegetation mapping); (2) more tightly linking numerical classification and spatial modelling through application of canonical classification techniques; and (3) enhancing the applicability of modelling to data-poor regions through employment of a new technique for modelling spatial pattern in compositional dissimilarity. 相似文献
83.
New concepts and computational models that integrate behavioral and neurophysiological observations have addressed several of the most fundamental long-standing problems in motor control. These problems include the selection of particular trajectories among the large number of possibilities, the solution of inverse kinematics and dynamics problems, motor adaptation and the learning of sequential behaviors. 相似文献
84.
Cristina G. Soto 《Reviews in Fish Biology and Fisheries》2001,11(3):181-195
The potential effects of global climate changeon marine protected areas do not appear to havebeen addressed in the literature. This paperexamines the literature on protected areas,conservation biology, marine ecology,oceanography, and climate change, and reviewssome of the relevant differences between marineand terrestrial environments. Frameworks andclassifications systems used in protected areadesign are discussed. Finally, a frameworkthat summarizes some of the importantoceanographic processes and their links to thefood chain are reviewed. Species abundance anddistribution are expected to change as a resultof global climate change, potentiallycompromising the efficacy of marine protectedareas as biodiversity conservation tools. Thisreview suggests the need for: furtherinterdisciplinary research and the use oflinked models; an increase in marine protectedareas for biodiversity conservation and asresearch sites for teasing apart fishingeffects from climate effects; a temporallyresponsive approach to siting new marineprotected areas, shifting their locations ifnecessary; and large-scale ecosystem/integratedmanagement approaches to address the competinguses of the oceans and boundary-less threatssuch as global climate change and pollution. 相似文献
85.
In typical treatment planning of 3D IMRT, the incident energy fluence is optimized to achieve a homogeneous dose distribution to the PTV. The PTV includes the tumour but also healthy tissues that may have a different dose response for the same incident energy fluence, like bony structures included in the PTV (mandibles in head and neck tumours or femoral bones in sarcomas). Dose to medium optimization compensates for this heterogeneous response, leading to a non-homogeneous energy fluence in the PTV and a non-homogeneous dose in the CTV in the presence of geometric errors. We illustrate qualitatively this statement in a cylindrical geometry where the PTV includes a CTV (7 cm diameter) made of water surrounded by ICRU compact bone (1.2 cm thickness); such configuration was chosen to exaggerate the aforementioned effect. Optimization was performed assuming dose equals photon energy fluence times mass energy absorption coefficient. Bone has a 4% lower dose response in a 6 MV flattening filter free spectrum. After optimization either in medium or assuming everything as water composition, the geometry was shifted by 1.2 cm and dose recomputed. As expected, compensating for the under-response of the bone material during optimization in medium leads to an overdosage of the CTV when patient geometric errors are taken into account. Optimization in dose assuming everything as water composition leads to a uniform coverage. Robust optimization or forcing a uniform atomic composition in the PTV margin may resolve this incompatibility between the PTV concept and dose to medium optimization. 相似文献
86.
Malin L. Pinsky Eli Fenichel Michael Fogarty Simon Levin Bonnie McCay Kevin St. Martin Rebecca L. Selden Talia Young 《Population Ecology》2021,63(1):17-26
Rapid climate changes are currently driving substantial reorganizations of marine ecosystems around the world. A key question is how these changes will alter the provision of ecosystem services from the ocean, particularly from fisheries. To answer this question, we need to understand not only the ecological dynamics of marine systems, but also human adaptation and feedbacks between humans and the rest of the natural world. In this review, we outline what we have learned from research primarily in continental shelf ecosystems and fishing communities of North America. Key findings are that marine animals are highly sensitive to warming and are responding quickly to changes in water temperature, and that such changes are often happening faster than similar processes on land. Changes in species distributions and productivity are having substantial impacts on fisheries, including through changing catch compositions and longer distances traveled for fishing trips. Conflicts over access to fisheries have also emerged as species distributions are no longer aligned with regulations or catch allocations. These changes in the coupled natural-human system have reduced the value of ecosystem services from some fisheries and risk doing so even more in the future. Going forward, substantial opportunities for more effective fisheries management and operations, marine conservation, and marine spatial planning are likely possible through greater consideration of climate information over time-scales from years to decades. 相似文献
87.
Environmental planning must determine management practices for a given territory based on the landscape processes that have occurred over time and their consequences. Therefore, environmental planning decisions must be based on strong empirical evidence that can be easily understood by all involved parties. Several studies have highlighted the methodological deficiencies that occur when obtaining and interpreting such issues, particularly in heterogeneous landscapes with complex interactions. In this paper, we evaluated two methodological approaches that are used in management planning, land use/cover change (LUCC) and mosaic change (MC) to compare their effectiveness and suitability for supporting decision-making. We applied these methods to the coastal landscape of São Sebastião Island, Brazil, which has undergone many changes in the last 50 years. For two years, land use/cover maps were produced using GIS and assessed according to changes in landscape elements (LUCC) and boundaries (MC). Overall, the LUCC failed to identify sets with similar structural heterogeneities in the landscape. However, the LUCC is easier for stakeholders to understand and apply than the MC. The MC method better presented the evolution of the relationship between the landscape elements and heterogeneity. 相似文献
88.
Laurel Mast 《Bioethics》2020,34(3):264-271
Significant criticisms have been raised regarding the ethical and psychological basis of living wills. Various solutions to address these criticisms have been advanced, such as the use of surrogate decision makers alone or data science-driven algorithms. These proposals share a fundamental weakness: they focus on resolving the problems of living wills, and, in the process, lose sight of the underlying ethical principle of advance care planning, autonomy. By suggesting that the same sweeping solutions, without opportunities for choice, be applied to all, individual patients are treated as population-level groups—as a theoretical patient who represents a population, not the specific patient crafting his or her individualized future care plans. Instead, advance care planning can be improved through a multimodal approach that both mitigates cognitive biases and allows for customization of the decision-making process by allowing for the incorporation of a variety of methods of advance care planning. 相似文献
89.
The assessment of the value of ecosystem services is a valuable tool for biodiversity conservation that can facilitate better environmental policy decision-making and land management, and can help land managers develop interventions to compensate for biodiversity loss at the patch level. Previous studies have suggested that it is appropriate to assess the value of biodiversity for conservation planning by considering both the condition of the landscape and the spatial configuration of adjacent land uses that can be reflected as a proximity effect. This research examines the influence of spatial proximity on biodiversity conservation from the ecosystem service perspective based on the assumption that the variation in the proximity effect caused by land cover change has positive or negative impacts on ecological services. Three factors related to the spatial characteristics of the landscape were considered in this approach: the relative artificiality of the land cover types, the distance decay effect of patches and the impact of one land cover type on others. The proximity effect change (PEC) parameter reflected the relationship between the spatial proximity effect and biodiversity conservation. The results of a quantitative and spatial comparative analysis of the proposed method and the conventional method in Yingkou for the periods of 2000–2005 and 2005–2010 showed that the former can account for the temporal and spatial changes in ecosystem services for biodiversity conservation that were caused by patch-level changes as well as the interaction between the altered and adjacent patches from a spatial perspective. The metric can also identify the most critical areas for biodiversity protection and inform the efficient allocation of limited land resources for nature conservation to maximize the benefit to biodiversity by guiding the process of land-use change, particularly urbanization and agriculture. Future studies should focus on the other important factors that are applicable to the assessment of the value of biodiversity conservation in socio-ecological systems, where society and nature are mutually capable of fulfilling their roles. 相似文献
90.
《Current biology : CB》2022,32(1):190-199.e3