Sensitivity of penman-monteith reference crop evapotranspiration in Tao’er River Basin of northeastern China

A non-dimensional relative sensitivity coefficient was employed to predict the responses of reference crop evapotranspiration （ET0） to perturbation of four climate variables in Tao＇er River Basin of the northeastern China. Mean monthly ET0 and yearly ET0 from 1961 to 2005 were estimated with the FAO-56 Penman-Monteith Equation. A 45-year historical dataset of average monthly maximum/minimum air temperature, mean air temperature, wind speed, sunshine hours and relative humidity from 15 meteorological stations was used in the analysis. Results show that： 1） Sensitivity coefficients of wind speed, air temperature and sunshine hours were positive except for those of air temperature of Arxan Meteorological Station, while those of relative humidity were all negative. Relative humidity was the most sensitive variable in general for the Tao＇er River Basin, followed by sunshine hours, wind speed and air temperature. 2） Similar to climate variable, monthly sensitivity coefficients exhibit large annual fluctuations. 3） Sensitivity coefficients for four climate variables all showed significant trends in seasonal/yearly series. Also, sensitivity coefficients of air temperature, sunshine hours and wind speed all showed significant trends in spring. 4） Among all sensitivity coefficients, the average yearly sensitivity coefficient of relative humidity was highest throughout the basin and showed largest spatial variability. Longitudinal distribution of sensitivity coefficients for air temperature, relative humidity and sunshine hours was also found, which was similar to the distribution of the three climate variables.     

Environmental evolution of Gongwang Mountains during Holocene in northeastern Yunnan, China

This paper presents the study on two continuous glacio-lacustrine sedimentary deposits, Laotanfang （3 597 m） and Shibantang （3 689 m） located on the southern and northern sides of Hulifang peak in Yunan, China. Environmental change indexes are constructed for each deposit, based on grain size, geochemical and pollen analysis, environmental magnetic susceptibility, and 14C dating. The study of climatic environmental change since the Holocene epoch in this region shows that the climate fluctuated at different stages during the early Holocene, that is, the climate was cool and wet during 8.4-7. 7r ka, cold and wet during 7.7-6. 5 ka, cold and dry during 6. 5-4.7 ka, cool and wet during 4.7-2. 1 ka, warm and wet during 2. 1-1.0 ka, and warmer and wet since 1 ka. These findings reflect the overlapping influences of the southwest and southeast monsoons in different times during the Holocene in the north part of southwestern China are in accord with other Holocene climate change models in this part of China.     

太湖蓝藻水华遥感动态监测预警信息系统

太湖蓝藻水华暴发对其周边地区的生态、经济和社会造成了严重影响,对蓝藻水华进行监测预警对于改善太湖水环境具有重要意义。本文在分析蓝藻水华遥感监测预警研究动态基础上,从信息系统构建角度,结合太湖蓝藻水华监测情况,对太湖蓝藻水华遥感监测预警流程进行系统性分析,提出建立太湖蓝藻水华遥感监测预警系统的总体框架,利用C#语言和IDL语言实现了该框架的软件架构,并且论述了实现该系统框架所采用的系统集成技术和软件模式技术。     

基于NiosII的远程温度监控系统

介绍一种嵌入式远程温度监控系统。系统采用Dallas单线数字温度传感器DS18B20采集现场温度数据,采用NiosII作为上位机且配置成嵌入式服务器,构成远程温度控制系统。借助互联网,实现对温度进行远程监控。与传统温度监控系统比较采用了嵌入式的服务器,减小硬件体积,提高了实时性。并给出该系统的硬件原理图和程序流程图。     

RTK配合全站仪在数字化测图中的应用

本文主要叙述了RTK配合全站仪进行数字化测图的可行性,介绍了RTK的系统组成、工作原理,并对RTK配合全站仪联合测图的作业流程进行了一系列论述;指出了RTK与全站仪联合进行数字化测图是一种高速度、高效率的新方法.     

高程基面问题浅议

介绍国内现存的几种高程基面,分析工程中使用高程基面时存在的问题,提出测量系统规范化、标准化的紧迫性和必要性。     

南极DOME-A区域GPS测量精度等级的探讨

以DOME-A区域第24次南极GPS测量为案例,进行了GPS测量精度与起算点分布、观测时间长短、以及数据处理软件关系的实验,统计分析了不同情况下的GPS控制点坐标精度误差,探讨确定了其精度等级和应用范围,最后的结论可供南极测量GPS用户参考.     

GIS中位置关系的定性描述及其推理

位置关系的定性描述是指用方向关系和定性距离描述目标对象相对于参照物的位置关系的方法.此处的研究重点是采用基于投影的方向关系和定性距离建立位置关系定性描述模型,推导了位置关系的描述公式,并根据该公式研究位置关系的定性推理,用MATLAB语言模拟了位置关系定性推理.研究中,以相邻定性距离的距离范围之比k=5为例,取ε≤1/k2,则只要δi/δj≤ε,就有δi±δj≈δj.实际上,位置关系的定性推理结果与具体的k值无关.     

“网格化”城市管理系统中城市部件数字化采集方法的探讨

为了有效地实施"网格化"城市管理,提高城市管理效率,加快城市管理体系的建立,需要全面掌握城市部件的分布和现状情况。城市部件是"网格城市"的基础,高质量的数据采集是提高管理效率的根本。根据具体项目中城市部件采集工作,讨论了有效实用的、又有别于城市测绘的数字化采集方法和步骤,所获取的有效成果证明了该采集方法的可行性。     

EXERCISE IN DOWNSCALING ON SEA SURFACE TEMPERATURE ALONG CHINESE COAST

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