Methodologies of preparing erosion features map by using RS and GIS

The erosion features map is one of the basic maps in erosion and sediment studies and watershed management programs. Some methodologies of preparing erosion features map by using RS and GIS were compared in research which took place in the Jajrood sub-basin in north-east Tehran, Iran. In the first phase, four working units＇ maps were prepared by integration a） plant cover, geology and slope b） land use, geology and slope c） land use, rocks sensitivity to erosion and slope and d） land use, rocks sensitivity to erosion and land units＇ layers. In addition to these four working units＇ maps, three more maps were also evaluated in separating erosion features including e） land units f） sensitivity of rocks to erosion and g） image photomorphic units. The efficiency of these seven working units＇ maps was evaluated by 314 control points. For this purpose, by using erosion features of control points regarding field views, surface, rill, gully and channel erosion maps were prepared and compared by crossing them with working units＇ maps. Results showed that method ＂d＂ was better than ＂a＂, ＂b＂ and ＂c＂ in providing soil erosion features regarding economic and executive considerations. The accuracy of methods ＂e＂ and ＂f＂ was 53.0 and 42.9% and their Root Mean Squared Error was more than method ＂g＂ and methods ＂a＂ to ＂d＂. The coefficient of variation was highest for methods ＂e＂ and ＂f＇ and the least for method ＂e＂ and the greatest precision was related to image interpretation.     

汾渭平原东部运城市空气污染变化特征及其气象因素影响分析

本文综合利用2015—2020年地面气象观测资料、欧洲中心ERA5再分析资料及大气环境监测数据,分析了汾渭平原东部运城市污染物浓度的变化特征以及与天气形势和气象要素的关系。结果表明：①2015—2020年期间运城市PM2.5、PM10、SO2、NO2、CO 5种污染物年平均浓度呈下降趋势,而O3浓度呈上升趋势;②冬季和夏季空气质量相对较差,首要污染物分别是PM2.5和O3,边界层高度的变化与近地层风向风速、污染物浓度的关系密切,冬季（夏季）PM2.5（O3）污染较重时边界层高度较低（较高）,以东北风（东南风）为主,风速偏小（偏大）;③最后利用自组织映射神经网络（SOM）算法分别对冬夏925 hPa位势高度场进行天气分型并开展不同天气形势下污染物浓度与气象要素的变化对比研究,发现冬季污染时以静稳天气为主,低层弱东北风将污染物输送至运城市,而夏季O3污染较重时受热低压形势控制,利于O3前体物汇合,太阳辐射较强时O3浓度较高。     

自组织网络与广义回归网络耦合的副热带高压指数预测

利用亚洲夏季风系统中各成员变化活动与西太平洋副高存在的不同程度的时延相关性,从1995~ 2004年NCEP/NCAR逐日再分析资料中,提取了亚洲夏季风系统各成员变化活动的特征指标及其对应的超前三候的西太平洋副高(简称副高)面积和脊线指数.在此基础之上,建立了自组织网络与径向基函数网络串级耦合的副高指数预测模型.该模型首先用自组织网络对各指标样本按其自身相似原则进行无监督分类,随后用广义回归网络分别对分类出的各指数样本子集进行有监督的训练建模和预测.模型的预测试验结果表明：副高指数的预测结果与其实际值之间的相关系数达到0.89,明显优于单一的神经网络模型预测效果.     

一种数字正射影像图制作方法

数字正射影像图(DOM)是一种新型数字测绘产品,具有信息丰富、直观、精度高等特点,在城市规划、土地管理、环境分析、地籍测量等方面得到广泛应用。本文以航空影像(DMC影像)为例,根据生产实践,探讨利用Inpho软件的各相关模块制作DOM的方法和技巧。实践证明,利用Inpho系列软件制作DOM具有生产速度快、费用低、精度高等特点,是生成DOM的良好方法。     

Compilation of serial maps on karst geology of China and Southeast Asia

The compilation of serial maps of karst geology in China and Southeast Asia is a project under the “One Belt One Road” geological survey plan granted by China Geological Survey. This paper summarized the research trend of geoscientific mapping in China and Southeast Asia and introduced the significance, contents, technical routes, operating methods and progress of the project. Through bilateral and multilateral cooperation, this project builded an international cooperation platform for mapping and completes the preliminary compilation of related karst geological maps in China and Southeast Asia, thus filling up the blank of karst geological maps in this region.     

黑龙江省位置服务中心建设与服务模式探讨

对黑龙江省位置服务现状进行了分析,提出了建立的黑龙江省位置服务中心的框架。位置服务中心的建立是以手机、PDA及各种移动手持终端定位服务、车辆监控等为主的服务体系,并通过WMS方式对外提供地图服务。文中对位置服务中心的设计理念、体系结构及服务模式进行了详细描述,并对其具体应用进行了探讨,最后对未来3G时代位置服务中心的应用前景进行了展望。