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241.
大兴安岭天保工程区生态系统服务变化研究   总被引:3,自引:0,他引:3  
郑树峰  王丽萍  臧淑英 《地理科学》2021,41(7):1295-1302
利用Landsat和MODIS遥感数据和InVEST模型,评估了1990―2015年大兴安岭天保工程区实施前后生态系统土壤风蚀量、生境质量和碳储量的时空变化,并通过地理探测器方法对生态系统服务时空变化分布与趋势进行驱动因子探测和交互作用探测分析。结果表明:① 从空间分布来看,额尔古纳市南部、鄂温克族自治旗西北部、科尔沁右翼前旗的土壤风蚀量大,生境质量差,碳储量低。② 2000年天保工程实施之后,森林面积显著增加,土壤风蚀量减少1.14%,生境质量增加0.49%,碳储量减少幅度为0.12%,低于2000年以前的0.64%。③ 土壤风蚀量主要受植被类型、土壤类型的影响,生态系统类型、植被类型对生境质量、碳储量空间异质性的影响显著大于其他因素,海拔、坡度2种地形因子对土壤风蚀量、碳储量的解释能力很小。温度、降水2种气候因子对土壤风蚀量、生境质量和碳储量的解释能力不固定,但仍是不可或缺的因素。  相似文献   
242.
刘志涛  王少剑  方创琳 《地理学报》2021,76(11):2797-2813
生态系统服务是生态要素、结构、功能和产品造福于人类社会的媒介和通道。根据生态系统服务价值(ESV)及其影响机制调节人类社会对生态系统的利用强度和保护方式,对于实现人地和谐的可持续发展目标具有重要意义。本文以粤港澳大湾区作为研究对象,依托遥感数据修订ESV核算结果,更加准确地揭示2000—2015年粤港澳大湾区ESV的时空演变特征,并引入面板分位数回归深入探索生态系统服务影响因素的分段效应,增加对生态系统服务影响机制的认识。结果显示:① 2000—2015年粤港澳大湾区ESV减速下降,下降区域主要分布在粤港澳大湾区中部和珠江入海口两岸等城市快速扩张区。② 在城市交界处,土地利用变化会带来更为强烈的ESV变化。③ 在ESV水平不同的区域,影响因素具有不同的影响效果。用地完整度仅在ESV的低值区可以促进生态系统服务能力提升。气温对生态系统服务能力的正向作用随ESV的提高而增强,经济密度对生态系统服务能力的负向作用随ESV的提高而减弱,二者均会导致ESV高值区与低值区间的差距增大,形成“自然马太效应”。  相似文献   
243.
Regional ecological health,the core of comprehensive ecosystem assessments,is an important foundation for regional exploration,environmental conservation,and sustainable development.The mountainous areas in southwest China are backward in economy,but industrialization and urbanization have been rapid in recent years.This study assessed the ecosystem health of the Sichuan and Yunnan provinces in China using a pressure-state-response(PSR)model.Spatiotemporal patterns of regional ecosystem health were analyzed from 2000 to 2016,including overall characteristics as well as local characteristics.Ecosystem health in most regions was improved over time(Y=0.0058 X–11.0132,R2=0.95,P<0.001),and areas with poorer ecosystem health decreased from half to one-third of the total area.Analysis of the primacy ratio and the variation coefficient confirmed that the gap in health scores between regions has gradually expanded since 2007,but there are more high quality regions overall(Z of Moran’s index<1.96,P>0.05).Overall,the regional ecosystems to the east of the Hu line-an imaginary line dividing east and west China into roughly equivalent parts-were healthier than those to the west.The pressure and state scores of ecosystems were determined by physiographic condition,and the response scores by government policies and social concern.The spatiotemporal patterns of ecosystem health were dominated to a greater extent by natural than anthropogenic factors,which explains why the shift in the patterns aligned with the direction of the Hu line.Dividing regions into key management areas based on natural geographical conditions and socioeconomic development could contribute to the formulation of a reasonable ecological and environmental protection policy,guaranteeing ecosystem services in the long run.  相似文献   
244.
Analysis of Earth observation (EO) data, often combined with geographical information systems (GIS), allows monitoring of land cover dynamics over different ecosystems, including protected or conservation sites. The aim of this study is to use contemporary technologies such as EO and GIS in synergy with fragmentation analysis, to quantify the changes in the landscape of the Rajaji National Park (RNP) during the period of 19 years (1990–2009). Several statistics such as principal component analysis (PCA) and spatial metrics are used to understand the results. PCA analysis has produced two principal components (PC) and explained 84.1% of the total variance, first component (PC1) accounted for the 57.8% of the total variance while the second component (PC2) has accounted for the 26.3% of the total variance calculated from the core area metrics, distance metrics and shape metrics. Our results suggested that notable changes happened in the RNP landscape, evidencing the requirement of taking appropriate measures to conserve this natural ecosystem.  相似文献   
245.
Wetland biomass is essential for monitoring the stability and productivity of wetland ecosystems. Conventional field methods to measure or estimate wetland biomass are accurate and reliable, but expensive, time consuming and labor intensive. This research explored the potential for estimating wetland reed biomass using a combination of airborne discrete-return Light Detection and Ranging (LiDAR) and hyperspectral data. To derive the optimal predictor variables of reed biomass, a range of LiDAR and hyperspectral metrics at different spatial scales were regressed against the field-observed biomasses. The results showed that the LiDAR-derived H_p99 (99th percentile of the LiDAR height) and hyperspectral-calculated modified soil-adjusted vegetation index (MSAVI) were the best metrics for estimating reed biomass using the single regression model. Although the LiDAR data yielded a higher estimation accuracy compared to the hyperspectral data, the combination of LiDAR and hyperspectral data produced a more accurate prediction model for reed biomass (R2 = 0.648, RMSE = 167.546 g/m2, RMSEr = 20.71%) than LiDAR data alone. Thus, combining LiDAR data with hyperspectral data has a great potential for improving the accuracy of aboveground biomass estimation.  相似文献   
246.
陕西河谷盆地生态系统服务协同与权衡时空差异分析   总被引:6,自引:1,他引:5  
陕西河谷盆地是区域主要粮食基地和社会经济中心,人口增长、城镇化和工业化的加快发展,使得该地区生态环境受到人类活动的强烈冲击,生态环境面临着潜在的巨大危机,严重影响社会经济的可持续发展。本文选取西北地区经济中心—关中盆地和陕西省生态保护指定区—汉中盆地进行对比研究,以1990-2010年的生态系统服务数据(NPP、保水服务、食物供给)分析生态服务时空差异,通过相关分析、线性和幂函数回归等方法分析了生态系统服务协同与权衡的时空差异。结果表明:NPP与保水是协同关系,NPP与食物供给、保水与食物供给是权衡关系;21年中,两大盆地的协同关系均呈减弱趋势,权衡关系为加强趋势,且关中盆地的变化速度要高于汉中盆地;NPP与保水的协同程度,在关中盆地东部的耕地区域以及汉中盆地的宁强县与略阳县西部最强,以关中的铜川市和汉中的西乡县最弱;NPP与食物供给的权衡程度,在关中盆地的铜川市和西安市境内的秦岭区域以及汉中盆地的西乡县南部制约关系更为突出,以关中的宝鸡市及汉中的略阳县最弱。  相似文献   
247.
生态系统服务权衡研究进展:从认知到决策   总被引:27,自引:5,他引:22  
作为沟通自然生态系统与人类社会的重要桥梁,生态系统服务一直以来都是地理学、生态学等学科的研究前沿和热点。正确认知生态系统服务之间的关系,是开展多种生态系统服务可持续管理决策的前提,有助于人类福祉的全面提升。本文通过厘定生态系统服务权衡的概念内涵,梳理了生态系统服务权衡的空间、时间和可逆性特征,将多层次人类福祉的满足作为权衡的最终目标,视生态补偿为权衡决策的基本保障途径。生态系统服务权衡关系的识别依托于定量指标法和综合模型法,且权衡关系可能随时空尺度的推移发生改变;情景分析与多目标分析是生态系统服务权衡决策的有效手段。生态系统服务权衡多尺度关联、生态系统服务流与远程耦合、生态系统服务消费与生态补偿,成为当前生态系统服务权衡研究的重点方向。  相似文献   
248.
In this paper, we present a reflexive examination of how and why we, an academic and a practitioner, arrive at different evaluations of collaborative progress in natural resource management. We situate this examination in our long-standing involvement in designing, adaptively managing, and participating in the Uncompahgre Plateau collaborative forest restoration project in western Colorado, USA. Drawing on the concept of “positionality” in qualitative social science research, we disclose our respective motivations, assumptions, roles, and power relative to the collaborative process. The differences in evaluating collaborative progress stem from our respective professional positionality. For the academic, the guiding interest was to test theory and promote success for his applied research institute; for the practitioner, the motivation was to build trust to allow her field staff the flexibility to implement management actions and demonstrate effectiveness as an agency line officer. These epistemological differences draw attention to the importance of transdisciplinary approaches to producing knowledge from shared practice, starting with efforts to explicitly disclose and honor differing interests, assumptions, and frames of reference stemming from each party’s personal and professional biographies and institutional norms. This reflexivity is essential to advancing knowledge about collaboration in natural resource management.  相似文献   
249.
Sense of place, including an individual’s attitudes toward specific geographic settings, is generally predicted to influence willingness to engage in place-protective behaviors. Relatively little research, however, has empirically examined the influence of people’s attitudes toward a place on their willingness to pay for environmental protection. Using the example of a payment for ecosystem services (PES) initiative in the McKenzie River watershed, Oregon, USA, we found that place attitudes were a significant predictor of respondents’ willingness to pay for a program designed to benefit drinking water quality. These results suggest that connecting conservation actions to landscapes that are meaningful to people may increase their financial support for PES and other conservation programs. While program managers have little or no influence over stakeholders’ political ideology, gender, or income, managers may be able to influence prospective PES buyers’ awareness and attitudes through targeted communications, thereby potentially increasing support for place-based conservation efforts.  相似文献   
250.
陈端吕  陈哲夫  彭保发 《地理研究》2018,37(9):1692-1703
土地利用生态服务价值体现了土地通过集约利用与空间优化所发挥生态效益的大小,可在一定程度上反映土地利用与与经济发展的协调关系。以西洞庭湖区为研究对象,在ArcGIS软件支持下,通过评价与分析生态服务价值变化,分析生态经济协调发展水平及其空间差异,探讨土地利用生态服务价值与区域经济发展的互动响应与耦合协调关系。研究表明:① 2000年以来西洞庭湖区土地利用生态服务价值呈下降趋势,2000年西洞庭湖区生态服务价值为1292.13×106元·a-1,2011年为953.03×106元·a-1,损失339.10×106元。② 从整个研究区来看,整个研究阶段处于低度冲突的县有6个,分别为常德市辖区、安乡县、汉寿县、澧县、临澧县、津市市,只有桃源县处于潜在危机状态。从数量上看,整个区域内大多为冲突状态,区域在经济发展中存在的潜在危机较大。③ 从空间分异来看,2008年与2011年土地利用生态经济协调度基本上为低度冲突状态,需采取生态服务供给恢复与重建措施,控制生态服务消费需求的过快增长。整个区域只有桃源县与汉寿县由不协调转换为协调状态,主要原因是森林覆盖率相对较高,林地类型面积大,水土保持与水源涵养生态服务功能较强,提高了生态服务价值。  相似文献   
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