干旱区绿洲土地利用与覆被变化过程

应用遥感和GIS技术及数理统计学方法,以新疆三工河流域冲洪积扇－冲积平原型绿洲为研究区,利用1978年、1987年和1998年的遥感数据,深入研究了70年代中后期以来干旱区绿洲LUCC的过程和趋势。结果表明：(1) 遥感和GIS在绿洲土地利用与覆被变化数据获取和空间分析方面是一种非常强大而有效的技术手段;(2) 通过建立绿洲LUCC的幅度、速度、区域差异和变化趋势数学模型,可以较好的研究绿洲土地LUCC的过程和趋势,如变化的双向性、单向性、正向性和反向性,变化的涨势或落势等,在三工河流域绿洲应用取得良好效果;(3) 自70年代中后期以来三工河流域绿洲LUCC趋缓,并存在显著的时空差异：前期绿洲LUCC处于单向转换过程的非平衡状态,并呈现一定的地段分异,其中绿洲上部处于准平衡状态,而绿洲中部和下部处于非平衡状态。后期绿洲LUCC呈现双向转换为主的发展态势,使绿洲LUCC处于准平衡状态;绿洲上部和中部处于非平衡状态,绿洲下部处于平衡状态,均表现出不同的变化过程和趋势。     

乌鲁木齐风廓线雷达的探测能力评估

利用2011年12月~2013年3月CFL－03型风廓线雷达在乌鲁木齐市的风探测数据与同期的常规探空数据开展了比对分析,从而对风廓线雷达探测数据的可靠性和探测能力给予了评估。结果表明,受乌鲁木齐四季不同的气候背景影响,CFL－03型风廓线雷达的数据获取率在夏季最高,在冬季最低,80%的数据获取率等值线夏季、冬季各自达到的高度分别为4500m和1980m;受低空地物回波、探测盲区等因素影响,240m以下风廓线雷达探测的风速误差较大,240m以上风廓线雷达四季探测的风速普遍小于实况,误差在-1~0m/s之间的出现频率最高,介于28.8%~31.8%,且在四季最大频率出现的高度有所差异,总体来看夏季风速误差相对较小;风向误差总体在-22.5°~0°之间的出现频率最高,且随着高度增加频率增加;风廓线雷达风速的探测能力优于风向,二者与实况的相关系数各自为0.9左右和0.6~0.8;通过长时间序列的风速、风向资料的比较,说明CFL－03型风廓线雷达能够较为准确地反映冬季天气过程的演变,且能够较为精细地刻画夏季短时强降水天气过程中高低空气流的变化特点。在综合考虑低空地物回波、探测盲区因素以及高空气球探空飘移等多种因素影响的情况下,可见CFL－03型风廓线雷达对乌鲁木齐大气环境和天气过程拥有较可靠的监测能力。     

南北地震带区域形变异常特征与地震关系研究

利用南北地震带及附近地区20世纪70年代以来的区域水准网和90年代以来的GPS监测网资料, 结合地质构造和监测区发生的多次6级左右及以上震例, 分析了震前区域性形变场异常的基本特征。 进而根据资料支持程度, 分别以GPS、 区域水准观测位移为地表约束, 以“973”项目活动地块划分结果为地质依据, 进行非震负位错模型反演计算, 研究了数值模拟结果反映的活动块体和边界断裂构造变形状态与地震的关系。 在此基础上, 定性与定量相结合分析研究了强震前区域性水平、 垂直构造形变异常特征及可能的机理, 初步总结了基于区域水准、 GPS观测与数值模拟的强震前区域构造形变异常的一些判据。     

海洋边界层内风、浪相互作用研究进展

鉴于海洋边界层内风、浪相互作用在海洋、大气研究中的重要意义,本文较详细地回顾、总结了国内外有关海洋边界层风、浪相互作用的研究进展：由最初的关于风应力和空气动力粗糙长度的统计研究发展到后来的利用模式探讨海洋边界层的结构和风、浪耦合机制。最后简单讨论了风、浪耦合研究中存在亟待解决的问题以及未来的研究前景。     

Soil moisture temporal stability and spatio-temporal variability about a typical subalpine ecosystem in northwestern China

Knowledge of the spatial–temporal variability of soil water content is critical for water management and restoration of vegetation in semi-arid areas. Using the temporal stability method, we investigated soil water relations and spatial–temporal variability of volumetric soil water content (VSWC) in the grassland–shrubland–forest transect at a typical semi-arid subalpine ecosystem in the Qilian Mountains, northwestern China. The VSWC was measured on 48 occasions to a depth of 70 cm at 50 locations along a 240-m transect during the 2016–2017 growing seasons. Results revealed that temporal variability in VSWC in the same soil layer in the three vegetation types and averaged across vegetation types tended to exhibit similar patterns of a decrease with increasing soil depth. Temporal stability in each vegetation type was stronger with an increase in soil depth. However, the results of temporal stability determined with standard deviation of relative difference (SDRD) disagreed with those based on the Spearman's rank correlation coefficient; the forest site had the highest Spearman rank correlation coefficient while the shrubland—the smallest SDRD in the 0–20 cm soil layer. Correlation analyses of VSWCs between two vegetation types indicated that soil water was related among all three vegetation types at the 0–20, and 0–70 cm soil layer, but in the 20–40 and 40–70 cm soil layers, significant correlation (p < .01) occurred only between adjacent vegetation types. In the upper soil layer (0–20 cm), soil water relations were mainly affected by surface runoff. In the lower soil layer (20–40 and 40–70 cm), soil water relations among the three vegetation types were highly complex, and probably resulting from a combination of root distribution and activity, interflow, and the impact of deep soil freeze–thaw dynamics. These results suggest that the factors affecting soil water are complex, and further research should address the relative importance of and interactions among different determining factors.     

The effect of estimating areal rainfall using self‐similarity topography method on the simulation accuracy of runoff prediction

Rainfall input for hydrologic modelling is assumed uniformly distributed over the entire catchment. This can lead to significant errors. Investigations of areal rainfall in mountain areas are typically limited by a lack of adequate meteorological and hydrogeological records. This study focuses on areal rainfall in mountain areas within the Kaidu River Basin, China, with the aim of analyzing the influence of areal rainfall on the simulation accuracy of runoff prediction. We conducted a simulation using MIKE 11/NAM rainfall‐runoff model over 92 days of the rain season and compared the simulation error in different methods. On the basis of properties of self‐similarity degree (SSD) in analyzing the detailed characteristics of terrain, areal rainfall was calculated to model the runoff. The results of the model simulations are generally consistent with observed data, indicating that the self‐similarity topography method is able to reflect the spatial change of rainfall. This indicates that the proposed methodology is applicable for the management of water resources in mountain area. The modelling and self‐similarity topography method study allowed quantification of the spatial rainfall and provided an insight into their implications in hydrological forecasting. Copyright © 2011 John Wiley & Sons, Ltd.     

遥感技术在“一张图”实施监督系统中的应用

结合国土空间规划“一张图”实施监督信息系统的开发,详细阐述了卫星遥感技术在规划实施评估、国土空间开发适宜性评价和规划监测预警这几个模块中的应用案例,对应用的内容、方法及效果进行了总结和探讨。分析表明,遥感技术能为国土空间规划“一张图”提供众多的基础数据,对于评估城市发展动态、合理规划城市用地具有非常重要的作用。     

一种基于空间分析服务链组合的自然资源保护红线审计模型方法

区别于传统的审计方法,针对领导干部自然资源资产离任审计,提出一种空间分析服务链组合的自然资源保护红线审计空间分析建模方法,实现了自然资源保护红线审计的地理处理分析服务链模型,并将其应用到云南省领导干部自然资源资产离任审计工作中。实验表明,该模型具有可行性能够辅助审计部门工作人员快速发现疑点线索,简化用户操作,提高审计效率。     

基于多源信息与深度学习特征提取的人口空间抽样方法

人口抽样调查是通过人口样本估算区域人口总体的一种手段。由于人口分布通常具有空间差异性,传统的抽样调查理论难以满足日益增长的空间抽样需求,合理高效的人口空间抽样调查方法对于人口统计、研究人类活动、解决城市问题等有重要意义。本文提出一种基于多源信息与深度学习特征提取的人口空间抽样方法。在不透水面信息的辅助下,利用四叉树分割进行分层抽样,初步选择出可能存在人口分布的调查样本,并通过深度学习的常用模型——卷积神经网络估算样本建筑物密度,以辅助最终调查样本的选择与调查方案的制定。研究结果证明,该方法能够有效地筛选与人口分布密切相关的抽样区域,排除大量的无用样本,提高了人口调查的效率,节约了大量调查成本。