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951.
选取基础教育、社会保障、基本医疗、公共文化四大类指标,利用2008—2013年我国26个省份163个中小城市的统计数据,测度了其基本公共服务水平区域均等化程度的动态变化。结果表明:中小城市基本公共服务平均水平呈上升趋势;基础教育和基本医疗的区域均等化程度较好,社会保障和公共文化的区域差异较大;基本公共服务水平表现出空间集聚发展态势,东高西低的分布格局呈加剧之势。优化公共财政体制建设,加强省份间协同发展是促进基本公共服务均等化的重要途径。  相似文献   
952.
The exponential growth of natural language text data in social media has contributed a rich data source for geographic information. However, incorporating such data source for GIS analysis faces tremendous challenges as existing GIS data tend to be geometry based while natural language text data tend to rely on natural language spatial relation (NLSR) terms. To alleviate this problem, one critical step is to translate geometric configurations into NLSR terms, but existing methods to date (e.g. mean value or decision tree algorithm) are insufficient to obtain a precise translation. This study addresses this issue by adopting the random forest (RF) algorithm to automatically learn a robust mapping model from a large number of samples and to evaluate the importance of each variable for each NLSR term. Because the semantic similarity of the collected terms reduces the classification accuracy, different grouping schemes of NLSR terms are used, with their influences on classification results being evaluated. The experiment results demonstrate that the learned model can accurately transform geometric configurations into NLSR terms, and that recognizing different groups of terms require different sets of variables. More importantly, the results of variable importance evaluation indicate that the importance of topology types determined by the 9-intersection model is weaker than metric variables in defining NLSR terms, which contrasts to the assertion of ‘topology matters, metric refines’ in existing studies.  相似文献   
953.
黑河中游地区耕地景观演变及社会经济驱动力分析   总被引:4,自引:6,他引:4  
选取1987~2010年的土地利用数据,运用变化轨迹分析方法以及景观指数表征黑河中游地区耕地景观的演变过程,采用偏最小二乘回归模型分析耕地景观演变的驱动力。结果表明:从耕地的变化轨迹来看,研究期间耕地的扩张是黑河中游地区耕地景观演变的主要趋势;从空间上来看,扩张型耕地和缩减型耕地分布趋向集中,主要集中在稳定型耕地边缘,同时耕地扩张的方向趋向河流;从驱动因素分析来看,总人口、城市化、产业发展、机电井数等是促使耕地景观演变的主要社会经济驱动因素,但是各个驱动因素的驱动作用均有差异。  相似文献   
954.
程绍文  李艳  张晓梅  李照红 《地理科学》2017,37(10):1569-1576
以武当山为研究案例地,通过游客问卷与访谈调查,采用SPSS18.0统计软件定量分析武当山旅游体验对游客认知、思想、行为意愿等的影响。研究结果表明,① 武当山游客的旅游动机有宗教朝圣、文化体验、娱乐放松及感情交流4类;② 宗教文化旅游影响游客对目的地的形象感知及对道教文化的认知、态度及践行意愿;宗教文化旅游对游客的影响强弱因动机而不同,自强至弱依次为宗教朝圣、文化体验、感情交流及娱乐放松。  相似文献   
955.
改革开放以来中国农业政策效果的时空计量分析   总被引:1,自引:0,他引:1  
Since reform and opening up, how much contribution has China’s implementation of new agricultural policy made to agricultural output? This paper is trying to establish an agricultural policy output econometric model for doing a quantitative analysis of China’s new agricultural policy. The results show that China’s agricultural policies on agricultural output have an average contribution rate of about 7% since 1978, which is consistent with the OECD’s basic forecast. There are obvious temporal and spatial differences. Generally speaking, we can divide the contribution of agricultural policy into three periods, which are the start-up phase from 1978 to 1991 (14 years), the stationary phase from 1992 to 2002 (11 years) and the rising phase from 2003 to 2008 (6 years). In space, the contribution of agricultural policy underwent a process from the all-low in the start-up phase, the gradual increase in the stationary phase to the all-high in the rising phase. Northern and western regions are more sensitive to policies. There are three major factors that can affect the contribution of regional agricultural policies, which are the process of national industrialization strategy, terrain and the level of local finance.  相似文献   
956.
促进经济与环境协调是煤炭城市可持续发展的关键和核心。采用物质流分析、脱钩分析和分解分析等方法,深入分析了1995—2007年徐州市经济增长与资源环境之间的脱钩类型、可持续状态及驱动因素。结果表明:研究期内徐州市DMI和DPO的年均增长率分别为2.74%和0.91%,而GDP年均增长率为12.62%,二者之间呈较为明显的正相关关系,而物质代谢效率的提升又使其发展方式呈现向资源节约型、环境友好型发展模式转型的趋势;资源投入、废物排放与经济增长之间均出现弱脱钩现象,表明徐州经济系统正处于显著的弱可持续发展态势;经济规模扩大和技术效应抑制作用减弱是引起煤炭城市资源环境约束性增强、可持续发展降低的主要驱动因素。  相似文献   
957.
南极绕极流区中尺度涡动动能年际变化和转换机制   总被引:1,自引:0,他引:1       下载免费PDF全文
采用多种资料研究南大洋南极绕极流(Antarctic Circumpolar Current,ACC)区中尺度涡的年际变化规律及机制.通过分析网格化融合卫星海洋资料AVISO(Archiving,Validation and Interpretation of Satellites Oceanographic DATA...  相似文献   
958.
Maar lakes in the Auckland Volcanic Field are important high-resolution archives of Holocene environmental change in the Southern Hemisphere mid-latitudes. Stable carbon and nitrogen isotope analyses were applied on bulk organic matter and the green alga Botryococcus from a sediment core from Lake Pupuke (Auckland, North Island, New Zealand) spanning the period since 7,165?cal.?year BP. The origin of organic matter was established using total-organic?Ccarbon-to-nitrogen ratios (TOC/TN) as well as organic carbon (??13COM) and nitrogen (??15N) isotope composition of potential modern sources. This approach demonstrated that the contribution of allochthonous organic matter to the lake sediment was negligible for most of the record. The sedimentary TOC/TN ratios that are higher than Redfield ratio (i.e. >7) are attributed to N-limiting conditions throughout the record. Variations of nitrogen and carbon isotopes during the last 7,165?years are interpreted as changes in the dominant processes in the lake. While epilimnetic primary productivity controlled isotope composition before 6,600?cal.?year BP, microbial processes, especially denitrification and methane oxidation, caused overall shifts of the ??15N and ??13C values since the Mid-Holocene. Comparisons with climate reconstructions from the Northern Island suggest that changes in the wind-induced lake overturn and a shift to more pronounced seasonality were the most likely causes for lake-internal changes since 6,600?cal.?year BP.  相似文献   
959.
As a solid reservoir, a glacier can regulate regional water resources. The annual net mass balance directly reflects the fluctuation of the glacier and climate variability. Based on 51 years of mass balance observation data, the mass balance of Tianshan Mountains Urumqi Glacier No. 1 experienced a nine times positive balance fluctuation and nine times negative balance fluctuation. There were 35 and 16 negative and positive balance years, respectively. From 1996/97 to 2008/09, 12 consecutive negative balance years were observed at Tianshan Mountains Urumqi Glacier No. 1. These results demonstrate that the Urumqi Glacier No. 1 is experiencing a strong negative balance, and the strongest negative balance, -931 mm w.e. (mm water equivalent), during the observation period occurred in 2008. In addition, the cumulative mass balance reached 13,709 mm w.e. in 2008. However, in 2009, the mass balance was positive at 63 mm w.e. The equilibrium-line altitude changes with the fluctuation in the mass balance, and the effective mass balance gradient is 7.4 mm/m. In this paper, the headwaters of the Urumqi River were analyzed using meteorological data from 1958 to 2009, including the average seasonal temperature and precipitation. The results showed that the main factor associated with the mass balance variation of Glacier No. 1 is the fluctuation in the summer air temperature, followed by changes in the precipitation.  相似文献   
960.
砒砂岩区地貌形态三维分形特征量化及空间变异   总被引:3,自引:0,他引:3  
张传才  秦奋  王海鹰  李宁  李阳 《地理科学》2016,36(1):142-148
针对现有地貌形态三维分形模型结构存在的不足,构建一个新的地貌形态三维分形维数测算模型。基于该模型对砒砂岩区274个小流域的地貌形态三维分形维数进行计算并分析其空间变异规律。研究表明:① 基于该模型计算的分形维数能更准确地反映地貌形态复杂度信息;② 砒砂岩区小流域地貌形态三维分形维数介于1.683 6~1.948 6之间;③ 地貌形态三维分形维数整体上覆土砒砂岩区(均值为1.765 9)<裸露砒砂岩强度侵蚀区(均值为1.785 4)和剧烈侵蚀区(均值为1.774 8)<覆沙砒砂岩区(均值为1.796 6)。由于地表覆盖物、砒砂岩裸露程度和土壤侵蚀机理的差异而形成的不同地貌特征是该区地貌形态分形特征空间变异的主要原因。  相似文献   
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