景观敏感度的理论及其应用意义   总被引：4，自引：0，他引：4  

姚允龙  吕宪国  佟守正 《地理科学进展》2007,26(5):57-64

1. 中国科学院东北地理与农业生态研究所, 长春130012; 2. 中国科学院研究生院, 北京100039  相似文献   

Factors Inhibiting Local Government Engagement in Environmental Sustainability: case studies from rural Australia     

Barbara Pini  Su Wild River  Fiona M. Haslam McKenzie 《The Australian geographer》2007,38(2):161-175

The literature on local government management of the environment in Australia has been limited in that it has typically focused on the urban sphere. In contrast, this paper places rurality at the centre of its inquiry. It uses data from 15 case studies of rural local governments in Australia to identify the main factors that inhibit natural resource management by rural councils. These barriers mobilise around four key themes: capacity, commitment, co-ordination and community. While many of the issues raised in this study of non-urban shires have been described in previous research, the paper argues that the geographic location of the areas under investigation aggravates barriers to engaging sustainability initiatives. It is contended that rural local governments need to be resourced accordingly to ensure that natural resource management at the local government level in Australia is not compromised.  相似文献   

GAINS中重力传感器信息的扰动改正     

李姗姗  吴晓平 《测绘学院学报》2007,(4)

重力辅助惯性导航系统GAINS(Gravity Aided Inertial Navigation System)是利用地球物理特征信息──重力来完成水下运动载体的辅助惯性导航与定位。为实现重力匹配以校正惯性导航随时间累积的误差,首先必须对重力传感器输出信息进行扰动改正。分析了水下运动状态下重力传感器受到的各种重力扰动,如垂直扰动加速度、水平扰动加速度以及厄特弗斯效应影响所产生的原因,研究了扰动误差模型与INS导航精度之间的关系,并通过计算,提出了可直接以INS输出数据而无需其它外部有源导航信息进行扰动分离的方法。  相似文献   

地表形变D-InSAR监测方法及关键问题分析   总被引：2，自引：0，他引：2  

葛大庆  王艳  范景辉  刘圣伟  郭小方  王毅 《国土资源遥感》2007,18(4):14-22

总结和分析了地表形变D-InSAR监测的主要方法和当前所面临的主要问题。针对常规D-InSAR技术中大气相位和低相干区域相 位解缠，分别介绍了基于Delaunay三角网的不规则格网解缠方法、累积干涉纹图处理方法（Stacking Interferograms）、永久性 散射体（PS）技术以及角反射器干涉测量（CR-InSAR）方法，分析了各自的适用条件和优缺点。此外，对有限数据量条件下低相干 区域大气相位校正、相干目标识别等问题进行了重点讨论。立足于工程应用需要，分别对D-InSAR测量地表形变的参数选择、测量 结果的精度验证、D-InSAR测量值与形变的关系、大区域处理以及形变场时空演变等问题进行了分析和讨论。  相似文献   

Experimental study on phosphorus release from sediments of shallow lake in wave flume   总被引：2，自引：2，他引：2  

SUN Xiaojing  ZHU Guangwei  LUO Liancong  QIN Boqiang 《中国科学D辑(英文版)》2006,49(Z1)

Influence of wave on sediment resuspension and nutrients release from sediments, collected from Lake Taihu and Lake Chaohu, was studied in flume experiments. Under strong-wave conditions, concentrations of suspended solids (SS), total phosphorus (TP) and dissolved total phosphorus (DTP) in overlying water were increased significantly following the sediments re-suspension. During the experiments on sediments of Lake Taihu and Lake Chaohu, TP concentrations increased 6 times and 3 times, and DTP concentration increased 100% and 70% more than it in presuspension, respectively. Concentration of soluble reactive phosphorus (SRP) of experiment on sediment of Lake Taihu increased 25%. During the massive sediment suspension, the dissolved phosphorus in pore water and much of the phosphorus adsorbed by the sediment particles were released into overlying water. The phenomena in this wave flume experiment are quite similar to the situation observed in situ of Lake Taihu. The critical wave stresses of sediment re-suspension are nearly equal. The change of concentrations of SS, TP, and SRP was the same as that in situ situation. This study showed that concentrations of TP and SRP in lake water could be increased significantly by wave disturbance. Phosphorus release was significantly enhanced by wave disturbance at the beginning of massive sediment re-suspension, but decreased later.  相似文献   

Nutrient fluxes induced by disturbance in Meiliang Bay of Lake Taihu   总被引：1，自引：0，他引：1  

LUO Liancong  QIN Boqiang  ZHU Guangwei  SUN Xiaojing  HONG Dalin  GAO Yajun  XIE Rui 《中国科学D辑(英文版)》2006,49(Z1)

A wave flume experiment was conducted to study nutrient fluxes at water-sediment interface of Meiliang Bay under different hydrodynamic conditions. The results reveal that hydrodynamics has remarkable effects on nutrient fluxes in this area. With a bottom wave stress of 0.019 N m-2 (equivalent to disturbance caused by wind SE 5-7 m s-1 at the sediment sample site of Meiliang Bay), the fluxes of TN, TDN and NH4+-N were separately 1.92× 10-3, -1.81 × 10-4 and 5.28× 10-4 mg m-2 s-1(positive for upward and negative for downward), but for TP, TDP and SRP, the fluxes were 5.69 × 10-4, 1.68 × 10-4 and -1.29 × 10-4 mgm-2 s-1. In order to calculate the released amount of nutrients based on these results, statistic analysis on the long-term meteorological data was conducted.The result shows that the maximum lasting time for wind SE 5-7 m s-1 in this area is about 15 h in summer. Further calculation shows that 111 t TN, 32 t NH4+-N, 34 t TP and 10 t TDP can be released into water (the sediment area was 47.45% of the whole surface area), resulting in concentration increase of 0.025, 0.007, 0.007 and 0.002 mg L-1 separately. With stronger disturbance (bottom wave stress is 0.217 N m-2 which is equivalent to disturbance caused by wind SE 10-11 m s-1 at the same site), there has been significant increase of nutrient fluxes (1.16× 10-2, 6.76×10-3, 1.14× 10-2 and 2.14× 10-3 mgm-2 s-1 for TN, DTN and NH4+-N and TP). The exceptions were TDP with flux having a decrease (measured to be 9.54× 10-5 mgm-2 s-1 ) and SRP with flux having a small increase (measured to be 5.42 × 10-5 mgm-2 s-1). The same statistic analysis on meteorological data reveal that the maximum lasting time for wind SE 10-11 m s-1 is no more than 5 h. Based on the nutrient fluxes and the wind lasting-time, similar calculations were also made suggesting that 232 t TN, 134.9 t TDN, 228 t NH4+-N, 42.7 t TP, 2.0 t TDP and 1.1 t SRP will be released from sediment at this hydrodynamic condition resulting in the concentration increases of 0.050, 0.029, 0.049, 0.009, 0.0004 and 0.0002 mg L-1. Therefore in shallow lakes, surface disturbance can lead to significant increase of nutrient concentrations although some components in water column had negative flux with weak disturbance (e.g. TDN and SRP in this experiment). In this case, sediment looks to be a source of nutrients. These nutrients deposited in sediment can be carried or released into water with sediment resuspension or changes of environmental conditions at water-sediment interface, which can have great effects on aquatic ecosystem and is also the characteristics of shallow lakes.  相似文献   

安徽省级资源环境空间信息服务系统研究与开发   总被引：2，自引：0，他引：2  

马众模  陈政  徐振宇  周燕林 《地理科学》2003,23(3):342-347

研究建立一个结构规范、服务便捷的省级资源环境空间信息网，实现资源环境空间信息的网络共享和服务已经是迫在眉睫。安徽省资源环境空间信息网首次在省政府网络上实现了资源环境空间信息的快速访问，具有数据最大、覆盖面全、类型多样的特点，并且采用SuperMap国产GIS软件进行开发，运行稳定、安全可靠，具有很好的可扩展性。系统地介绍了安徽省资源环境空间信息网的系统结构、数据库建设、数据更新和系统的主要功能。  相似文献   

施工干扰下的生态系统稳定性评价--以西气东输管道工程沿线新疆干旱荒漠区为例   总被引：5，自引：0，他引：5  

丘君  陈利顶  高启晨  姜昌亮  樊自立  李国强 《干旱区地理》2003,26(4):316-322

西气东输管道工程对沿线生态系统形成干扰，导致土壤质量下降。植被退化，生物多样性降低，风沙危害加剧等环境灾害，影响区域的生态安全．威胁到输气管道的安全运行。稳定性不同的生态系统对管道工程干扰有的反应不同．评价工程沿线生态系统的稳定性．有利于合理制定施工规范和开展工程后的生态恢复．对于保障区域生态系统和管道的双重安全具有重要意义。从生态系统受干扰后恢复能力的角度，在地理信息系统(GIS)平台支持下．采用图层投重-级别打分叠加模型，对管道沿线生态系统做稳定性评价。把生态系统稳定性按稳定性从低到高依次分为不稳定、欠稳定、稍稳定和稳定四个等级．结果发现沿线区域面积占15％的生态系统不稳定，52％区域欠稳定。针对稳定性低的盐土荒漠地区．沙质荒漠地区和棕漠土灌木荒漠三类地区，设计有利于促进生态系统恢复的友好环境构建对策。  相似文献   

西北地区重大工程地质问题研究     

苏生瑞  彭建兵 《工程地质学报》2003,11(1):105-110

根据2002年中国西北部重大工程地质问题论坛论文集和主题发言的资料,概述了西北地区的重大工程地质问题,包括区域稳定问题、活动断裂问题、特殊岩土体问题、高边坡问题、深埋长大隧道问题等。  相似文献   

原子荧光光度法测定地质化探样品中的砷、锑、铋     

刘瑛 《江苏地质》2003,27(2):92-93

原子荧光光度法分析As、Sb、Bi已被广泛应用，但由于仪器没有色散系统，所以干扰因素较多。阐述了原子荧光光度分析法中常见的干扰及其消除方法。方法简单、快速、灵敏、低耗。  相似文献