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51.
Marisa Naia Virgilio Hermoso Sílvia B. Carvalho José Carlos Brito 《水产资源保护:海洋与淡水生态系统》2021,31(7):1886-1900
- Systematic conservation planning in freshwater ecosystems faces multiple challenges because of the dynamic nature of rivers and their multiple dimensions of connectivity. In intermittent hydrological systems connectivity is functional when water is available, allowing the exchange of aquatic individuals between isolated freshwater ecosystems. Integrating these isolated systems in their hydrological context is essential when identifying priority areas for conservation, in order to try to minimize the propagation of threats into target water bodies (management units) from the surrounding landscape.
- Here, the use of a systematic planning approach is demonstrated to identify a set of priority management units to preserve freshwater biodiversity in an arid system of fragmented water bodies immersed in a landscape subject to a range of impacts.
- Twenty-six water-dependent taxa from 59 mountain rock pools (gueltas) of three southern Mauritanian mountains were used as a case study. A conservation planning tool (marxan ) was used to find priority conservation areas to integrate intermittent hydrological systems in their hydrological context, promote connectivity, and minimize the downstream propagation of threats. Three types of connectivity were analysed: (i) no connectivity, (ii) connectivity between gueltas, and (iii) connectivity between gueltas and sub-catchments.
- Considering different types of longitudinal connectivity affects the number and spatial allocation of the priority gueltas selected, and the conservation status of the gueltas and their upstream areas. Incorporating connections between gueltas and upstream locations in the modelling resulted in the selection of gueltas in areas with a low human footprint and in the increased connectivity of the solutions.
- The results obtained revealed important locations for local biodiversity conservation, and the method presented can be used when assessing the propagation of potential waterborne threats into isolated management units. The framework developed allows connectivity to be addressed in conservation planning. It can be replicated in regions with similar isolated habitats that connect through intermittent hydrological systems and can also be applied to lateral and vertical hydrological connectivity.
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针对我国农村电网的现状,阐述了农网网架规划的主要内容及规划方法,分析了几种网架规划中采用的智能优化算法,指出智能技术的应用是电网规划的发展方向。 相似文献
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针对我国绿道规划研究和实践的薄弱点,着重研究探讨了在城市内部即城市建设用地范畴下的绿道布局特征及布局控制方法。论文首先对于绿道在国外的发展和我国的实践情况进行概述,阐明了研究城市内部绿道规划的必要性;然后结合游憩需求圈层、居住区和公园绿地的等级特征划分了绿道的等级,并在此基础上梳理了绿道的空间布局特征;最后,围绕绿道布局量化控制,讨论了城市内部绿道布局量化控制指标体系建构和量化控制指标值的推导途径。 相似文献
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张精一 《中南林业调查规划》2008,27(4):40-45
基于质量管理的基本原则、方法和实践,对在ISO9001标准模式下建立林业调查规划设计质量管理体系进行探讨,从质量管理体系建立的必要性、基本要求、体系文件、实施要点等方面。阐述了林业调查规划设计质量管理体系建立的思路与方法。旨在提高林业调查规划设计管理水平和成果质量,满足开放式的市场竞争需要,更好地服务于现代林业建设事业。 相似文献
59.
Consuming Fuel and Fuelling Consumption: Modelling Human Caloric Demands and Fuelwood Use 总被引:1,自引:0,他引:1
This paper describes a conceptual framework that was developed to integrate livestock, human, cultivation and forest constraints
to model community fuelwood consumption over a 25-year planning horizon. This framework was constructed as an energy balance
based on human caloric requirements in order to examine the effects of household-level decisions for nutrition, fuelwood and
land use. A scenario from a virtual community in Uganda is presented to illustrate the utility of this model to allow rapid
policy and scenario evaluation. User-defined inputs combined with published research data are used in simulating resource
responses and energy consumption rates. This model is a potential tool to monitor fuelwood consumption and to understand the
implications of various land-use practices.
相似文献
Joel HartterEmail: |
60.
森林覆盖率是宏观规划的重要指标之一,国家林业局在2003年颁布了新的森林覆盖率计算方法,由于标准的变化,导致森林覆盖率宏观规划目标值的变化.文章阐述了新旧森林覆盖率标准的变化和关系,以云南为例,计算不同时期森林覆盖率的同标准指标,分析云南省森林覆盖率的规划目标,2015年宜为53%,2020年宜为57%,极限目标为63%. 相似文献