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121.
During the 15th Conference of the Parties(COP 15),Parties agreed that reducing emissions from deforestation and forest degradation and enhancing ’removals of greenhouse gas emission by forests’(REDD+) in developing countries through positive incentives under the United Nations Framework Convention on Climate Change(UNFCCC) was capable of dealing with global emissions.As REDD+ seeks to lower emissions by stopping deforestation and forest degradation with an international payment tier according to baseline scenarios,opportunities for ecosystem benefits such as slowing habitat fragmentation,conservation of forest biodiversity,soil conservation may be also part of this effort.The primary objective of this study is to evaluate ecosystem-based benefits of REDD+,and to identify the relationships with carbon stock changes.To achieve this goal,high resolution satellite images are combined with Normalized Difference Vegetation Index(NDVI) to identify historical deforestation in study area of Central Kalimantan,Indonesia.The carbon emissions for the period of 2000-2005 and 2005-2009 are 2.73 × 10 5 t CO 2 and 1.47 × 10 6 t CO 2 respectively,showing an increasing trend in recent years.Dring 2005-2009,number of patches(NP),patch density(PD),mean shape index distribution(SHAPE_MN) increased 30.8%,30.7% and 7.6%.Meanwhile,largest patch index(LPI),mean area(AREA_MN),area-weighted mean of shape index distribution(SHAPE_AM),neighbor distance(ENN_MN) and interspersion and juxtaposition index(IJI) decreased by 55.3%,29.7%,15.8%,53.4% and 21.5% respectively.The area regarding as positive correlation between carbon emissions and soil erosion was approximately 8.9 × 10 3 ha corresponding to 96.0% of the changing forest.These results support the view that there are strong synergies among carbon loss,forest fragmentation and soil erosion in tropical forests.Such mechanism of REDD+ is likely to present opportunities for multiple benefits that fall outside the scope of carbon stocks.  相似文献   
122.
对汉江上游进行野外实地详细调查,在湖北省郧县尚家河台地前沿发现了典型的全新世黄土-古土壤沉积剖面,通过粒度、磁化率、吸湿水和烧失量分析表明,黏粒、细粉砂、磁化率、吸湿水和烧失量在古土壤层S0出现高值,在L1、Lt、L0为低值;而粗粉砂、细砂粒和粗砂粒在S0为低值,在L1、Lt、L0为高值。这些指标的变化说明了全新世以来的气候和成壤环境的变化特征,即在古土壤S0形成时期,气候温暖湿润,成壤作用非常强烈;黄土堆积时期气候相对干旱,成壤作用较弱。  相似文献   
123.
Electric power consumption (EPC) is one of the basic indices for evaluating electric power use. Obtaining timely and accurate data on the spatiotemporal dynamics of EPC is crucial for understanding and practical deployment of electric power resources. In this study, an EPC model was developed using stable nighttime lights time-series data from the Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS). The model was used to reconstruct the spatial patterns of EPC in Chinese Mainland at the county level from 1995 to 2008. In addition, the spatiotemporal dynamics of EPC were analyzed, and the fol-lowing conclusions were drawn. (1) The EPC model reliably represented the spatiotemporal dynamics of EPC in Chinese Mainland with approximately 70% accuracy. (2) The EPC in most regions of Chinese Mainland was at low to moderate levels, with marked temporal and spatial variations; of high-level EPC, 58.26% was concentrated in eastern China. Six urban agglomerations (Beijing-Tianjin-Tangshan region, Shanghai-Nanjing-Hangzhou region, Pearl River Delta, Shandong Peninsula, middle-south of Liaoning Province, and Sichuan Basin) accounted for 10.69% of the total area of Chinese Mainland but consumed 39.23% of the electricity. (3) The EPC of most regions in Chinese Mainland increased from 1995 to 2008, and 64% of the mainland area showed a significant increase in EPC. Moderate increases in EPC were found in 61.62% of eastern China and 80.65% of central China from 1995 to 2008, whereas 75.69% of western China showed no significant increase in EPC. Meanwhile, 77.27%, 89.35%, and 66.72% of the Shanghai-Nanjing-Hangzhou region, Pearl River Delta, and Shandong Peninsula, respectively, showed high-speed increases in EPC. Moderate increases in EPC occurred in 71.12% and 72.13% of the Beijing-Tianjin-Tangshan region and middle-south of Liaoning Province, respectively, while no significant increase occurred in 56.34% of the Sichuan Basin.  相似文献   
124.
利用“地震预报计算机专家系统”的思想对大同 -阳高 Ms6 .1地震前每一前兆异常事件进行综合评估 ,以每一异常的最可能发震时间来计算发震概率 ,利用地震前兆综合加权信息熵研究了系统熵值与地震的关系。对华北地区的地震前兆综合加权信息熵研究表明 ,在大同 -阳高 Ms6 .1地震前 ,信息熵出现了明显的减熵有序变化  相似文献   
125.
黄河水利委员会提出了“维持黄河健康生命”的治河新理念,把维持黄河健康生命作为黄河开发与管理的终极目标。“堤防不决口,河道不断流,污染不超标,河床不抬高”是实现其终极目标的4个主要标志。河床不抬高就要通过综合措施解决泥沙问题,包括上中游拦减人黄泥沙,中下游采取人工调控水沙“关系”,在黄河下游挖河疏浚。在黄河下游窄河道特别是在河口地区挖河疏浚,减少其对下游河道的反馈影响,是维持黄河健康生命的重要措施之  相似文献   
126.
刘海龙  管志涛 《热带地理》2021,41(5):943-955
从产业环境、产业规模和产业效益3个维度构建综合评价指标体系,运用熵值法对中国2012—2018年省域尺度电影产业进行综合评价,运用GIS空间分析技术和地理探测器模型,分析其时空演变规律和影响因素.结果表明:1)2012—2018年中国电影产业发展整体水平不高,但发展速度显著提高,"T"字型空间结构逐渐形成,其发展空间格...  相似文献   
127.
????2008??8??~2010??9???浵??20??ENVISAT ASAR?????????PS??InSAR???????????е?????????????????????λ?????????????2008~2010??????α?????????α???????У??????????????????к??????????  相似文献   
128.
北京城郊农业区在不同时期因产业化、城市化的不同而承担着不同的发展目标, 其城乡一体化的进程及空间格局也出现了差异。本文运用历史沿革分析和数理分析方法对城乡一体化的功能结构及空间分布进行了研究, 结果表明:自1988 年以来, 处于近郊至远郊内缘的农业区(23~57 km处)的产业化、城市化分别出现了辐射式→飞地式、等级转移式→团块+扇状式+辐射式的空间发展;不同时期生态、经济、社会功能的组合和实现情况各有侧重, 多功能评价值相应地在“W”、“M”型空间格局之间转变。总体上, 北京郊区农业区的城乡功能及其综合效益都在增强, 但相对而言经济功能的作用在降低, 生态、景观功能在上升, 社会功能存在波动但总体趋强, 城乡功能的空间布局更加复杂, 而且这种发展态势直接影响着北京“十二五”期间多层次、多中心的城乡一体化建设。  相似文献   
129.
Rapid urbanization results in the conversion of natural soil to urban soil,and consequently,the storage and density of the soil carbon pools change.Taking Chongqing Municipality of China as a study case,this investigation attempts to better understand soil carbon pools in hilly cities.First,the vegetated areas in the study area were derived from QuickBird images.Then,topsoil data from 220 soil samples(0-20 cm) in the vegetated areas were collected and their soil organic carbon(SOC) densities were analyzed.Using the Kriging interpolation method,the spatial pattern of SOC was estimated.The results show that the SOC density exhibited high spatial variability in the urban topsoil of Chongqing.First,the SOC density in topsoil decreased according to slope in the order 2°-6° < 25°-90° < 0°-2° < 6°-15° < 15°-25°.Second,the newly developed areas during 2001-2010 had a lower SOC density than the areas built before 1988.Third,urban parks and gardens had a higher SOC density in topsoil,residential green land followed,and scattered street green land ranked last.For hilly cities,the variability of terrain affects the distribution of SOC.The Kriging results indicate that Kriging method combining slope with SOC density produced a high level of accuracy.The Kriging results show that the SOC density to the north of the Jialing River was higher than the south.The vegetated areas were estimated to amount to 73.5 km2 across the study area with an SOC storage of 0.192 Tg and an average density of 2.61 kg/m2.  相似文献   
130.
随着经济增长和产业结构的演变,农村劳动力与人口不断聚集城镇,城市化水平提高。相关分析表明,许昌市城市化与第二产业发展呈较强正相关,与第三产业发展无明显规律关系。因产业与企业基础现状、布局、区位、政策制度等原因,产业结构的变动对域内城市化水平的提升作用存在明显差异。集中培育发展优势第二产业、大力发展第三产业、加强教育培训、构建协调的推拉制度体系是提高许昌市城市化水平、实现城市化与产业结构演变协调发展的主要对策。  相似文献   
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