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11.
新形势下的土地变更调查任务不断增加,要求不断提高,手段不断强化,时间紧、任务重是当前土地变更调查面临的重大问题。针对以上问题,本文提出了一种动态变更的技术流程,通过深入研究土地规划实施、土地综合整治、地籍管理、耕地保护、执法监察等业务及相关关系,围绕"及时发现、快速调查、持续更新、如实上报、共享应用"5个方面的问题,以3S技术、网络技术、数据库技术等为支撑,提出以二调成果为基础,从土地管理业务内部及时发现变化,以发现驱动土地利用信息日常性持续动态变更的新思路。以成都市为例,开展基于3S技术的土地利用信息动态变更调查的方法在实际工作中的应用研究,实现了土地利用信息的"一图多用",并对变更结果进行了分析。 相似文献
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针对2012年5月28日河北唐山M 4.8地震,采用地磁谐波振幅比方法,分析昌黎、静海、红山及承德地磁台2007年1月至2015年12月地磁观测数据,结果显示:各台站10 min周期的计算结果波动性明显,其他周期形态较为一致;距震中最近的昌黎地磁台YZHx(NS)测向的10-40 min周期地磁谐波在下降至极低值后,开始转折时发生地震,而YZHy(EW)测向未出现明显转折现象;位于河北平原地震带中部的静海地磁台对此次地震反应显著,2个测向在震前均出现下降-转折-上升的变化特征。通过对比位于不同地区的4个地磁台站地磁谐波振幅比变化,发现受大范围整体构造应力场作用的影响,计算结果具有相似的趋势性变化特征,具体到局部地区或断裂带内部,各台站之间显示出一定差异。 相似文献
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Based on the research on the rural living standard in China in terms of annual net income per capita, we define six types of village-level economy, i.e. "to be extremely poor", "to make a basic living", "to dress warmly and eat one's fill", "to try to enrich (to disengage poverty)", "to be well-off" and "to be affluent". The data of average annual net income of all the 292 villages between 1990 and 2004 in rural Gongyi City, Henan Province were collected, verified and classified. By using standard deviation, coefficient of variation and regression analysis, it is found that the Gongyi's rural economy has boosted up remarkably from the relative-poverty and absolute-poverty stages in 1990 to the well-off in 2004. However, the absolute differences between villages present a trend of enlargement, while the relative differences fluctuating. On the other hand, spatial analysis of village-level economy shows that most villages with relatively high economic development level were located along national expressway and most villages with absolute-poverty lay in remote mountainous areas in 1990. Since the 1990s, the rapid urbanization and industrialization have had strongly positive effects on rural economic growth. Initial economic foundation, natural resources and traditional techniques also contribute to village economy. From the perspective of geography, villages with location advantages, such as near urban center or industrial parks, have more chances for their economic development and the "core-periphery" economic structure has been presented in the process of rural development. 相似文献
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Field observations of suspended particulate matter (SPM) in the Bohai Bay, China have not been widely reported. The aim of this paper is to describe the horizontal and vertical distribution of mass and volume concentrations of SPM, respectively, based on observed data at 312 stations in the northern Bohai Bay during summer of 2006. A numerical model ECOMSED coupled with a sediment transport module was also established to further discuss the mechanism of the thermocline effect on the vertical distribution of SPM. The mass concentrations of SPM exhibited high inshore values and low offshore values in the horizontal distribution; while in the vertical direction, characteristics of the volume concentration of SPM can be divided into two types: one with a sharp peak at depth of 10–15 m and another without. The peak value at the depth of the thermocline was resulted from concentrated phytoplankton. A numerical experiment further displayed that the thermocline can also prevent particles from being resuspended upward. 相似文献
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Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin 总被引:12,自引:1,他引:12
QIAO Yansong GUO Zhengtang HAO Qingzhen YIN Qiuzhen YUAN Baoyin LIU Tungsheng 《中国科学D辑(英文版)》2006,49(7):731-738
In northern China, the Quaternary loess-soil se-quences[1] and the Hipparion Red-Earth Formation in the eastern Loess Plateau[2―6] provide a continental climate record for the past 8 Ma. The recently reported Miocene[7] and Pliocene[8] loess-soil sequences near Qinan constitute an eolian record of the western Loess Plateau from 22 to 3.5 Ma. Earlier studies[9] place the Miocene loess deposits into the so-called Gansu Sys-tem. Our investigations show that the Gansu System contains inde… 相似文献
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万寿岩遗址位于福建省三明市,遗址之一的船帆洞中曾生活过两期古人类(40~37 kaBP和30~29 kaBP)。在第一期古人类的文化层中发现的人工石铺地面在我国旧石器考古中属重要发现,对研究末次冰期古人类生存环境具有重大意义。对船帆洞沉积物的植硅体分析显示,尖型植硅体和棒型植硅体数量比较占优势,扇型和块状植硅体含量其次,短细胞植硅体形态中鞍型的含量较多。结合聚类分析结果可将剖面至下而上划分为5个气候带,气候环境依次为凉干-冷干-冷偏干-凉偏干-温凉偏干。第一期古人类生活于带I底部,为凉干背景下较温暖的气候环境;第二期古人类生活于带Ⅳ上部,为凉偏干背景下较温暖的气候环境。植硅体的变化特征较好地指示了H4和H3事件,分别对应两期文化层。两次Heinrich事件改变了古人类的生存环境,推测是两期古人类离开船帆洞的主要原因。 相似文献
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Jinshui Liu Shuai Li Kaifei Liao Yuchi Cui Lei Shao Peijun Qiao Yi Lu Yuanli Hou Thian Lai Goh Yongjian Yao 《海洋学报(英文版)》2023,42(3):89-100
Both Pinghu and Huagang formations are important hydrocarbon reservoirs of the Xihu Depression in the East China Sea Shelf Basin. Clarifying the source suppliers and restoring source-to-sink transport routes are of great significance to the future petroleum and gas undertakings. Previous researchers were largely confined by either limitation of geological records, highly dependence on a singular method or low-precision dating techniques. Our study integrated heavy mineral assemblages, geochemica... 相似文献