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311.
随着全国性、地区性土地利用总体规划的制定与实施,探讨适台于土地利用总体规划环境影响评价的技术方法显得相当重要。在对生态系统服务功能价值评估研究进展进行评述的基础上。分析了生态系统服务功能价值评估在土地利用总体规划环境影响评价中应用的必要性.并结合实例对其应用方法进行了探讨.实例分析表明,生态系统服务功能价值评估在土地利用总体规划环评中的应用具有把土地利用的生态效益转化为简单易懂的货币形式.可为决策者提供直观的生态信息及生态系统服务功能价值。可作为一项量化指标。对土地利用总体规划目标及规划方案的生态效益进行综合评估,且核算简单。有助于节省规划环评的时间和资源等优势,本文还指出了进一步研究的方向。  相似文献   
312.
Arnold R. Parr 《Disasters》1987,11(2):148-159
Disasters do not affect everyone in the same way. Safety needs of the ten per cnet of the population who are disabled prior to disaster must be ascertained; contingency plans and preparations should be made to ensure that disabled persons. Consideration of the safety needs of disabled persons in disasters seems to have beenlargely neglected by emergency services and those voluntary and statutory organizations directly concerned with disablement.  相似文献   
313.
生态系统固碳服务是生态系统服务评估的重要指标之一,也是区域碳循环研究的重要组成部分,可以为减缓气候变化的区域碳管理提供决策依据.以厦门市森林生态系统为研究对象,选取VPM(Vegetation Photosynthesis Model)和ReRSM(Remote Sensing Model for Ecosystem Respiration)评估其2015年的固碳服务,并阐明其固碳服务的时空变异.结果表明:2015年厦门市森林生态系统固碳量(以C计)为31.36×104 t/a,平均固碳量为644.86 g/(m2·a),其时间动态总体呈单峰曲线分布,但受台风影响该曲线波动较大.厦门市森林生态系统固碳量空间格局总体表现为西北边缘地区较高、其他地区相对较低,与DEM的空间分布较为相似,且绝大部分区域为碳汇区.厦门市分区统计显示,同安区森林生态系统面积和固碳量均最大,分别占厦门市总量的52.58%和57.10%,其与翔安区、集美区的固碳量之和占厦门市总量的88.27%,是厦门市森林生态系统固碳的主体;湖里区固碳量最少,平均固碳量仅为14.25 g/(m2·a),几乎为碳中性.研究显示,厦门市森林生态系统具有较好的固碳能力.   相似文献   
314.
基于价值—风险的黄河上游生态功能区生态分区建设   总被引:2,自引:1,他引:1  
黄河上游地区生态环境脆弱,水土流失和土地退化等生态环境问题不断威胁着生态系统健康与人居环境质量。为探究黄河上游生态功能区生态环境安全状况,本文基于2000年、2010年和2018年的土地利用数据,借助生态系统服务模型、生态风险模型,定量分析了生态系统服务价值和生态风险指数的时空演变规律,并通过Z-score标准化的方法建设了四类生态分区。结果表明:(1)研究期内,各土地利用类型均发生不同程度变化,其中建设用地由于耕地和草地的转入增加最显著,增长面积为118 km2,增长率为46.36%。(2)研究区总体服务价值变化程度较小,生态系统服务以调节服务为主且草地提供价值最高。高服务价值区主要分布于临夏州西南部和卓尼县等植被覆盖度较高的地区。(3)研究区生态风险水平总体偏低,整体呈现“南北两端高、中间低”的分布特征,其中低、较低生态风险区占总面积的76%以上。(4)四类生态分区均发生了较小的变化,表明生态分区处于较为稳定的发展状态。不同生态分区的空间分布连续性差,其中以高生态系统服务价值—高生态风险区(I)最为典型。通过生态系统服务与生态风险(价值—风险)建设生态分区,可为协调区域人地关系与明确未来发展方向提供理论基础。  相似文献   
315.
Recycling across Ireland has increased incrementally since the introduction and implementation of the Landfill Directive 1999/31/EC, the WEEE directive 2002/96/EC, and the Waste Framework Directive 2008/98/EC. As a result of the implementation of the aforementioned directives, the volume of waste sent to landfill has fallen, household composting increased and recovery of municipal waste recyclables continues to improve. The improvements witnessed, are in part achieved as a result of the introduction of the 2-bin and 3-bin collection service. The improvement of facilities at recycling centres and bring banks have been instrumental in the gains achieved in recycling rates.NIMBYism, however, remains a constant impediment to procuring suitable sites for the recycling receptacles. It is not unusual for people to seek convenience whilst not wanting the associated problems on their doorstep. NIMBYism is something that most individuals are guilty of and it is considered to be quite normal. The structural difficulties associated with recycling rates are the first that need to be confronted. By altering the landscape, behaviours can be changed and improved. In the instance of bring banks and the social problems that are associated with them such as fly-tipping, changing the visual aspect of the receptacles and their positioning may improve recycling rates and reduce the number of instances of fly-tipping and littering.This paper presents the results of 509 questionnaires distributed to nine schools in the Limerick City and County environs. The questionnaires, distributed to primary schools actively participating in the Green School Programme, were analysed so as to get an understanding of the motivations and the deterrents surrounding household recycling of waste. From the analysis recommendations are made to reduce the social problems associated with bring banks and to increase the percentage of householders availing of waste collection services.  相似文献   
316.
辽河三角洲位于"辽宁沿海经济带",拥有重要的自然保护区和保存完好的大面积芦苇沼泽和以盐地碱蓬为主的潮间带盐沼,栖息着多种濒危物种.1980年以来,农业开发、水产养殖、油气开采活动加剧,使得该区域生态环境发生巨变.本研究分析了1980—2010年,辽河三角洲土地利用时空变化轨迹及驱动过程,并应用InVEST模型模拟了碳储存、生境质量、水质净化3种生态系统服务的时空变化,在此基础上进一步分析了土地利用变化与生态系统服务的关系.研究结果表明:辽河三角洲地区土地利用变化以围垦、修复、淤积3种驱动为主,社会经济驱动主导,自然驱动明显.碳储量和生境质量呈下降趋势,而水质净化功能波动变化.土地利用和生态系统服务相关性表明湿地可以提供较高水平的3种生态服务功能,而生态服务功能低的区域则多与建设用地重合.在规划保护区或实施保护性修复措施时,应优先考虑3种生态系统服务的高价值区域,以实现高效、经济的生态环境保护.  相似文献   
317.
选取2003年、2017年杭州湾南岸遥感数据,利用ENVI软件和ArcGIS进行空间校正和图像处理,获得海岸带湿地数据,基于InVEST模型研究杭州湾南岸15年间滩涂湿地蓝碳及其价值的变化.结果显示:(1)2003~2017年总碳储存量和单位面积碳储量最大值均呈上升趋势,总碳储存量由0.223亿t上升到0.765亿t,增加0.542亿t.单位面积碳储量最大值也由451.27t/hm2上升到1775.42t/hm2,湿地碳汇潜力增加.(2)2003~2017年研究区域无碳损失,总体表现为碳积累,蓝碳总量为0.543亿t,单位面积净碳固定最大值为1324.12t/hm2.(3)2003~2017年15年间杭州湾南岸海岸蓝碳总价值为4761.3亿元,单位面积蓝碳最大值为148.8万元,具有十分可观的生态价值.(4)滩涂蓝碳的储量同植被类型关系密切,研究区域芦苇作为优势种类,在提高本区域固碳能力中作用最大.(5)在预设的退塘还湿情景下,预测至2030年研究区固碳量和蓝碳价值增加明显.  相似文献   
318.
Conservation easements are the fastest growing private conservation strategy in the United States. However, mechanisms to assess private land conservation as well as their support by the general public are not well understood. This study uses the ecosystem services framework for assessing existing private lands in Idaho and identifies areas for future conservation easements. Using conservation targets of the land trust as a guide for selecting ecosystem services, we (a) mapped the spatial delivery of conservation targets across public and private lands, (b) explored public awareness in terms of social importance and vulnerability, and (c) mapped future priority areas by characterizing conservation bundles. We found that public lands provided the highest levels of conservation targets, and we found no difference in conservation target provision between private areas and conservation easements. The spatial characterization of conservation target bundles identified potential future priority areas for conservation easements, which can guide planning of land trust conservation efforts.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01323-x) contains supplementary material, which is available to authorized users.  相似文献   
319.
Integrated conservation approaches (ICAs) are employed by governments, communities, and nongovernmental organizations worldwide seeking to achieve outcomes with dual benefits for biodiversity conservation and poverty alleviation. Although ICAs are frequently implemented concurrently, interactions among ICAs and the synergies or trade-offs that result are rarely considered during program design, implementation, and evaluation. In support of more deliberate and effective use of ICAs, we examined interactions among four well-known strategies: biosphere reserves (BRs), voluntary protected areas (VPAs), payments for ecosystem services (PES), and community forest management (CFM). Through a comparative case study, we analyzed interactions among spatially or temporally clustered ICAs implemented on communally held and managed lands in three ecologically and socioeconomically distinct regions of Mexico. Our research methods combined policy analysis with data gathered through participant observation and semistructured interviews (n = 78) and focus groups (n = 5) with government officials, implementers, and participants involved in ICAs in 28 communities. Despite the significant differences among the regions in which they were implemented, we found that key actors at each level of involvement generally perceived interactions among ICAs as synergistic. The PES programs were perceived to strengthen protected areas by reducing forest cover loss in and around BRs, fostering proconservation attitudes, and incentivizing the establishment of VPAs. Communities that invested PES income in CFM were motivated to conserve forests beyond the duration of PES programs, and CFM in buffer zones was perceived to strengthen BRs by maintaining forest cover and generating income for communities. We also identified key social and environmental factors that can influence these interaction effects among ICAs. Based on these findings, we recommend further study of ICA interactions and intentionally complementary policy design to maximize positive environmental and social outcomes.  相似文献   
320.
Colonial burrowing herbivores can modify vegetation structure, create belowground refugia, and generate landscape heterogeneity, thereby affecting the distribution and abundance of associated species. Black‐tailed prairie dogs (Cynomys ludovicianus) are such a species, and they may strongly affect the abundance and composition of grassland bird communities. We examined how prairie dog colonies in the North American Great Plains affect bird species and community composition. Areas occupied by prairie dogs, characterized by low percent cover of grass, high percent cover of bare soil, and low vegetation height and density, supported a breeding bird community that differed substantially from surrounding areas that lacked prairie dogs. Bird communities on colony sites had significantly greater densities of large‐bodied carnivores (Burrowing Owls [Athene cunicularia], Mountain Plovers, [Charadrius montanus], and Killdeer [Charadrius vociferus]) and omnivores consisting of Horned Larks (Eremophila alpestris) and McCown's Longspurs (Rhynchophanes mccownii) than bird communities off colony sites. Bird communities off colony sites were dominated by small‐bodied insectivorous sparrows (Ammodramus spp.) and omnivorous Lark Buntings (Calamospiza melanocorys), Vesper Sparrows (Pooecetes gramineus), and Lark Sparrows (Chondestes grammacus). Densities of 3 species of conservation concern and 1 game species were significantly higher on colony sites than off colony sites, and the strength of prairie dog effects was consistent across the northern Great Plains. Vegetation modification by prairie dogs sustains a diverse suite of bird species in these grasslands. Collectively, our findings and those from previous studies show that areas in the North American Great Plains with prairie dog colonies support higher densities of at least 9 vertebrate species than sites without colonies. Prairie dogs affect habitat for these species through multiple pathways, including creation of belowground refugia, supply of prey for specialized predators, modification of vegetation structure within colonies, and increased landscape heterogeneity. Asociaciones de Comunidades de Aves de Pastizales con Perros de la Pradera en la Gran Llanura de Norte América  相似文献   
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