黄海生源要素的生物地球化学研究评述

根据黄海化学海洋学的调查和研究结果 ,概括并评述了生源要素 (包括溶解氧、pH、营养盐、CO2 与碳化学、叶绿素和初级生产力等 )生物地球化学研究的主要成果及其最新进展。提出了今后的探索方向和研究的侧重点。     

梯田保护利用的演化逻辑及外力影响因素

以世界文化遗产的云南红河哈尼梯田为例,基于元阳县自然资源局的土地利用的空间矢量数据,利用地理信息系统技术提取2013-2018年元阳县与梯田核心景区的土地利用类型信息,分析梯田耕作时空演变的总体特征和变化趋势,选取级差地租理论解释梯田耕作的演化逻辑,并通过实地调研说明政府的外力干预效果。结果表明：1）梯田核心区的耕地比例大于整个元阳县的耕地比例,且不同于元阳县内旱地面积大于水田面积,核心区内的水田面积为旱地面积的一倍,表明核心区的水田比非核心区保护得更好;2）在没有外力干预的自然情况下非核心区与核心区水田分别呈现改旱和撂荒趋势,民族内部的文化力量难以可持续抗衡这种变迁。而政府作为市场失灵的调控机关,在遗产保护任务和政治利益激励的诉求下,干预了核心区的梯田演变过程,通过提高级差地租Ⅱ实现核心区的土地增值,集中加大对核心区的资源要素投入,从而有效延缓了梯田遗产消失或变更的进程;而非核心区由于缺乏政府有力的干预,梯田正呈现逐渐消失的趋势。     

Statistical downscaling of IPCC sea surface wind and wind energy predictions for U.S. east coastal ocean,Gulf of Mexico and Caribbean Sea

A multivariate statistical downscaling method is developed to produce regional, high-resolution, coastal surface wind fields based on the IPCC global model predictions for the U.S. east coastal ocean, the Gulf of Mexico(GOM), and the Caribbean Sea. The statistical relationship is built upon linear regressions between the empirical orthogonal function(EOF) spaces of a cross- calibrated, multi-platform, multi-instrument ocean surface wind velocity dataset(predictand) and the global NCEP wind reanalysis(predictor) over a 10 year period from 2000 to 2009. The statistical relationship is validated before applications and its effectiveness is confirmed by the good agreement between downscaled wind fields based on the NCEP reanalysis and in-situ surface wind measured at 16 National Data Buoy Center(NDBC) buoys in the U.S. east coastal ocean and the GOM during 1992–1999. The predictand-predictor relationship is applied to IPCC GFDL model output(2.0?×2.5?) of downscaled coastal wind at 0.25?×0.25? resolution. The temporal and spatial variability of future predicted wind speeds and wind energy potential over the study region are further quantified. It is shown that wind speed and power would significantly be reduced in the high CO_2 climate scenario offshore of the mid-Atlantic and northeast U.S., with the speed falling to one quarter of its original value.     

Recent research progress and prospects in tourism geography of China

Based on a large number of domestic literature reviews with related research abroad, academic standards and issues awareness have been intensified in domestic tourism geography, disciplinary consciousness and innovation enhancement. Hence, some valuable achievements have been made in the areas of tourism resources, tourism regional system, the spatial structure of tourism, tourism flow, ecotourism, tourism industry, tourism planning and tourism impacts, which strengthened the traditional advantages of research, expanded new areas of research and made research trends diverse. Meanwhile, with innovation of research methods, tourism geography in China is getting more and more internationally-oriented and reflecting Chinese characteristics. Research trends of China’s tourism geography are prospected: 1) Catering to national strategic needs, persisting problem-oriented, strengthening the metatheoretical research, and building Chinese “localization” of theory of tourism geography and method system. 2) Introducing and assimilating foreign theories and research methods, while focusing on explaining new tourism phenomena and problems in the domestic socio-economic background. 3) Concerning about the new regional spatial processes of demographic process, social process, and spatial process in new tourism trend. 4) Exploring interactive process and mechanism of man-land relationship and new models to develop territorial space under the tourism impacts. 5) Exploring important research issues of tourism geography in global, national, regional and local scales, from the point of view of spatial differentiation, scale transformation, interaction of man and nature, creating tourism geography interpretation system based on “process-structure-mechanism” of China. 6) Building theoretical system actively, while strengthening application-oriented research, and focusing on tourism poverty alleviation, tourism and heritage protection, national parks’ construction and other hot issues. Faced with econometrics research boom, we should return to rational thinking, using big data scientifically, while paying attention to the important role of qualitative evaluation in future research.     

紫金山金-铜矿露天采矿场地下不明空区的地质雷达探测

采用先进的地球物理技术探明露天采矿场地下不明空区的分布情况,准确确定其平面分布范围、顶面埋深及空间高度,对保障露天采矿作业的安全进行、预防突发性事故的发生具有十分重要的意义。运用地质雷达对福建紫金山金铜矿露天采矿场地下不明空区进行探测,在两个不同探测区块共完成18条探测剖面,剖面线总长近4km;经处理后的实测地质雷达剖面具有高清晰度、高分辨率,能准确反映地下各种不同规模的不明采空区的属性、平面位置、顶板埋藏深度、空区大致高度;地质雷达探测共查明较大空区异常55个。采用50MHz天线的地质雷达系统在该露采场的有效探测深度可以达40m以上。在露天采矿场,地质雷达探测受矿区地形条件及环境影响很小,可直接在岩（矿）石表面进行,不受第四系覆盖层对雷达波衰减吸收的影响。因此,地质雷达非常适应露天采矿场地下采空区的探测及定位。     

上海市深基坑工程地面沉降评估理论与方法

深基坑工程是高层建筑、地铁隧道、地下空间开发利用等城市建设中的重要基础工程。随着土地节约集约化利用不断加强,基坑的深度与规模日渐提高。深基坑工程对区域地面沉降有明显影响。但针对性的地面沉降危险性评估尚属空白。根据深基坑工程地面沉降效应的理论分析与案例剖析,不同的设计施工方案对地面沉降有直接影响。含水层的疏干或降压是主要因素。地面沉降主要集中在开挖深度2倍的平面范围内,最远可达10~15倍开挖深度。地面沉降基本呈指数型衰减。现行的技术规程将2倍开挖深度范围作为基坑工程沉降监测与控制的重点。因此深基坑工程对区域地面沉降的影响评估应着重于15倍的开挖深度区间范围。提出了深基坑工程地面沉降评估的技术准则与主要技术环节的工作要点。     

Ground Moving Target Indication Using an InSAR System With a Hybrid Baseline

In this letter, a two-channel airborne experimental interferometric synthetic aperture radar (InSAR) designed for terrain height estimation is exploited to acquire the ability of ground moving target indication (GMTI). Due to the hybrid baseline of this system, the interferometric phase changes with the target motion as well as the terrain height. The fluctuation of the interferometric phase worsens the performance of the clutter suppression and the radial velocity estimation. In order to resolve this problem, a GMTI method with three steps is proposed. After two steps are used to eliminate the local flat-Earth phase and the cross-track interferometric phase of the scene, respectively, an adaptive filtering method is used to suppress the stationary clutter with the benefit of calibrating the sensor responses. A conventional constant false alarm rate detector is then used to indicate the moving targets. The validity of the proposed method is demonstrated with real data collected using an experimental airborne InSAR system.      

中国城镇化发展的地理学贡献与责任使命

城镇化是中国全面建成小康社会和实现现代化的必由之路,中国城镇化不仅决定着中国的未来,而且决定着世界城镇化的进程。近35 a来中国地理学家对中国城镇化发展做出了重要贡献,主要表现在：首次提出了城镇化的概念,推动城镇化上升为国家战略;率先将Northam提出的城镇化发展三阶段论修正为四阶段论;提出了中国城镇化发展合理进程并被《国家新型城镇化规划》采用;研制了中国新型城镇化综合区划,构建了中国新型城镇化合理格局;率先研制了城镇化发展质量定量测度方法与系统,为提升城镇化发展质量提供了技术支撑;较早发布了《中国新型城镇化发展报告》,提出了新型城镇化发展的通用模式和差异模式;首次提出了城镇化与生态环境耦合圈理论与技术图谱。中国地理学家在城镇化这一多学科研究的重大领域中经常扮演着组织者角色,并担当重任,主要是：综合分析城镇化发展面临的问题及国际经验,探索城镇化发展的驱动机制与基本规律,辨析城镇化发展的空间格局和差异模式,揭示城镇化发展与资源环境的耦合关系,模拟预警城镇化发展的多种情景与风险,选择城镇化发展质量提升的可持续之路。今后一段时间内,创新国家新型城镇化高质量发展理论,优化“一带一路”背景下中国城镇化发展的空间格局,揭示中国城镇化与生态环境交互耦合机理及规律,研制中国城镇化发展的智能决策支持系统与引导政策,是中国城镇化发展的地理学使命。