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601.
基于我国近海海洋综合调查与评价专项课题构建的生态系统健康评价指标体系和评价模式,应用数据库技术及面向对象的信息系统开发技术,研制了海洋生态系统健康评价软件,实现了评价过程的信息化、规范化、科学化。根据908专项调查数据,用该软件评价了我国近岸海域、近海海域及重点海域生态系统健康状况,制作了评价专题图,为海洋生态管理及决策支持提供重要的依据。  相似文献   
602.
通过剖析浮游植物生长特征和其集群结构与Si的重要性、Si的输入过程和生物地球化学过程以及Si限制浮游植物时间,揭示了在北太平洋的近岸水域,从秋天的雨季结束(11月)到春天的雨季开始(5月)之前,Si都限制浮游植物的生长,在北太平洋的远离近岸水域,浮游植物生长一直都受到Si的限制;探讨北太平洋风场变化的基本特点和规律与中国的沙尘暴发生、频率和强度,首次提出了北太平洋水域Si的提供系统,并且用框图模型说明了提供系统在运行过程中的每个流程。当北太平洋缺少Si时,该系统就向其水体输入大量的Si,来维持了北太平洋海洋生态系统的持续发展;为了补充输送到海洋的Si量减少,该系统提高了运行能力,造成内陆干旱、沙化面积扩大、沙尘暴强度增大。研究结果表明,在北太平洋水域,北太平洋的季风与北太平洋边缘的雨季在时间上密切相嵌,顺利完成近岸洪水和河流的输送与大气的输送之间的相互转换,一直保持向大海的水体输入大量的Si。而且,沙尘暴与北太平洋Si的缺乏在时间上紧密配合,其强度大小与Si缺乏的严重程度相一致。因此,人类在制定应对自然灾害的政策和战略时,要从人类的角度和地球的角度来共同考虑,有利于人类的健康生存,更应该有利于地球生态系统的持续发展。  相似文献   
603.
Abstract

Climate change will alter the capacity of carbon sequestration, and the risk assessment of carbon sequestration for terrestrial ecosystems will be helpful to the decision-making for climate change countermeasures and international climate negotiations. Based on the net ecosystem productivity of terrestrial ecosystems simulated by Atmosphere Vegetation Integrated Model, each grid of the risk criterion was set by time series trend analysis. Then the risks of carbon sequestration of terrestrial ecosystems were investigated. The results show that, in the IPCCSRES-B2 climate scenario, climate change will bring risks of carbon sequestration, and the high-risk level will dominate terrestrial ecosystems. The risk would expand with the increase of warming degree. By the end of the long-term of this century, about 60% of the whole country will face the risk; Northwest China, mountainous areas in Northeast China, middle and lower reaches plain of Yangtze River areas, Southwest China and Southeast China tend to be extremely vulnerable. Risk levels in most regions are likely to grow with the increase of warming degree, and this increase will mainly occur during the near-term to mid-term. Northwest China will become an area of high risks, and deciduous coniferous forests, temperate mixed forests and desert grassland tend to be extremely vulnerable.  相似文献   
604.
Abstract

Miyun County, located in the northeast of Chinese capital Beijing, was underwent remarkable variations in land use in recent years. This paper aimed to detect changes in land use of Miyun from 1997 to 2005, and to qualify the response of ecosystem to LUCC based on ecosystem services valuation. With two-periods TM images, we got land use change data, and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi. Results showed that water area, farm land and unused land decreased while residential land, forest land, grassland and orchard land increased during the study period. The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area. As for spatial variation, there were most dramatically land use change and ESV decline in reservoir ecological protection region. The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable. The driving forces of ESV loss were rapid population growth and economic development. More work should be done to make eco-environment stay healthy.  相似文献   
605.
生态资产是实现人类可持续发展的重要基础,如何科学评估和核算生态资产并建立生态补偿机制具有重要的学术价值与现实意义。本文从厘清生态资产的概念与范畴出发,梳理了有关生态资产核算方法与生态补偿机制的研究进展,并对下一步研究的重点提出了相关建议。本文认为,加强城市群生态资产相关研究很有必要,建议从生态资产空间流转与代谢的视角出发,综合考虑宏观方法与微观方法相结合,定量化评估生态资产的存量和流量,刻画生态资产的空间流转路径与代谢网络关系,深入分析关键利益相关方的价值偏好,构建市场化生态资产补偿机制,为实现生态资产合理利用提供重要的理论参考与实证参照。  相似文献   
606.
As a special ecosystem, an urban forest park, which is different from a regular “forest park”, is one of the key elements involved in improving the urban ecological environment and promoting the sustainable development of a city. The “urban forest park” can also significantly improve living conditions by acting as a greenbelt. The Chengdu Longquan Mountain Urban Forest Park is a rare mountain urban forest park located in the center of the city. This “urban forest park” not only provides more ecological products and maintains ecological security but also meets the growing needs of people for food, environmental quality, and spirituality. To comprehensively assess the ecological value of the Chengdu Longquan Mountain Urban Forest Park, this study used the literature analogy and questionnaire survey methods to establish a targeted ecosystem service assessment system in this study area. In addition, combined with the hierarchical analysis method, the indicator system was tested, and the specific evaluation index was determined. In the Longquan Mountain Urban Forest Park Ecosystem Service Value Index System, three first-level indicators, such as ecological material products (with a weight of 0.412 6), ecological regulation (0.327 5), and dwelling culture (0.259 9); eight secondary indicators, such as product production (0.206 3), resource supply (0.206 3), and biodiversity (0.194 4); and twenty-three tertiary indicators, such as air negative oxygen ion (0.154 7), habitat quality (0.095 9), and ecological health benefit (0.075 5), were identified. From the weights of the first and second indicators, it was clear that the supply of ecological material products is the main service function in the Longquan Mountain Urban Forest Park ecosystem. Moreover, from the weights of the third indicator, the public’s cognition and concept of the ecosystem service value of the “urban forest park” gradually shifted from the supply service of products and resources to cultural services. In summary, the ecosystem service value assessment system designed for the Longquan Mountain Urban Forest Park in this study has certain feasibility and extensibility that lays a theoretical foundation for the scientific assessment of ecological value and ecological value realization mechanism for other “forest parks” worldwide. © 2022 Authors. All rights reserved.  相似文献   
607.
中国自然资源生态服务重要性评价与空间格局分析   总被引:1,自引:0,他引:1  
自然资源是保障经济社会发展的重要物质基础,同时又发挥了重要的生态服务功能。选取水源涵养、水土保持、防风固沙、生物多样性维护和产品提供五类生态服务,采用NPP定量指标法识别中国自然资源生态服务的重要区域,并进一步分析空间格局特征。结果表明:中国自然资源生态服务极重要和高度重要区约占总面积的1/4,以东北山地、江南地区、西南地区和青藏高原东部等水源涵养能力强、水土保持较好、防风固沙水平高、生物多样性较丰富的地区为主;不同类型自然资源的生态服务重要性差异显著,耕地资源的产品提供服务重要性显著,林地和草地资源的水源涵养、水土保持、防风固沙及生物多样性维护服务重要性均较显著,水域主要提供水源涵养服务;各生态服务重要性在空间上均显著集聚,自然资源综合生态服务的热点区主要分布在大兴安岭、长白山、浙闽山地、武夷山、南岭山地、秦岭山地、滇西南地区和藏东南山地等;自然资源综合生态服务重要性的空间分布与农业自然带/亚带呈现较高的一致性,热带和温带地区的重要性级别较高。研究结果可为区域自然资源管理及生态保护修复提供决策依据。  相似文献   
608.
中国南北过渡带生态系统碳储量时空变化及动态模拟   总被引:3,自引:0,他引:3  
山地是全球变化的敏感地带,对生态安全与发展具有重要作用,山地生态系统服务变化和生态环境承载力是地理学与生态学的研究热点。以中国南北过渡带的主体秦巴山地为研究对象,采用CA-Markov模型与InVEST模型模拟和预测(2000—2040年)不同土地利用情景下秦巴山地生态系统碳储量变化,运用热点分析(Getis-Ord Gi*)探讨秦巴山地生态系统碳储量的空间分布差异。结果表明:(1)2000—2040年,研究区土地利用/土地覆被变化主要是耕地、林地、草地和建设用地。(2)2000—2020年,碳储量增加1.12×107 t;2020—2040年自然增长情景下,碳储量损失剧烈,减少50.24×107 t;生态保护情景下,碳损失幅度明显变弱,减少29.52×107 t,说明采取生态环境保护政策,能够有效控制碳储量减少。(3)土地利用/土地覆被与生态系统碳储量的变化呈现显著的一致性,土地利用数量变化决定了生态系统碳储量的质量和空间分布格局。(4)随着海拔抬升,碳储量呈现出“先增后减”的趋势;随着坡度升高,碳储量呈现出“W”型变化趋势。(5)热点分析结果显示,2000—2020年间,碳储量热点区和冷点区零散分布在研究区内;2040年自然增长情景下,碳储量冷热点分布范围有逐渐变大的趋势;2040年生态保护情景较2020年,秦巴山地生态系统碳储量的冷热点分布范围整体变化不大。  相似文献   
609.
基于联合国2030年可持续发展目标(UN-SDGs),融入生态系统服务,建立了面向易地扶贫搬迁政策的村落和农牧户尺度可持续发展评价指标体系,定量分析了西藏典型易地扶贫搬迁迁入村——白朗村及村内农牧户在搬迁前后可持续发展目标实现状况变化。结果表明:在村落尺度,易地扶贫搬迁实施后迁入村在消除贫困(SDG 1)、能源可持续(SDG 7)和可持续住区(SDG 11)三项目标下的可持续发展指标数值较搬迁前显著增加,但可持续发展指数总分降低2.91%;易地扶贫搬迁政策直接影响的农牧户收入、用水和交通等可持续发展指标的可持续发展指数贡献率从49.4%增加至54.23%,但政策间接影响的生态系统相关的指标,其可持续发展指数贡献率由50.6%降低至45.77%;在农牧户尺度,易地扶贫搬迁显著促进了搬迁农牧户消除贫困(SDG 1)和体面工作(SDG 8)目标的实现,且在村落资源总量有限、大量人口迁入的情况下原住农牧户各项可持续发展指标依然稳定增长。研究为白朗村搬迁后的管理和投入工作提供方向,并为未来其他地区搬迁工作中的土地利用规划制定和迁入人口数量的确定提供思路。  相似文献   
610.
Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
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