湖北气象监测网络业务管理系统及其应用效果     

龚贤创  谢从刚  杨代才  邢丽萍 《湖北气象》2008,27(3):278-282

为了提高省级综合气象观测业务的全面质量管理水平,整合气象信息资料传输管理、综合观测系统运行监控、自动站实时数据质量控制和短信报警等业务质量管理功能,设计开发了湖北省气象监测网络业务管理软件系统。目前,该系统已成为湖北省气象监测网络业务重要值班平台之一。系统投入业务运行以来,湖北省各类气象资料收集上传质量呈现上升并保持稳定的趋势,自动气象站实时资料经自动数据质量控制后数据质量有较大程度的提高。由于采用主流成熟技术开发,系统具有较好的可推广性。  相似文献   

IMU/DGPS辅助航空摄影测量中检校场布设方案研究   总被引：6，自引：0，他引：6  

李学友  倪忠礼 《测绘工程》2005,14(4):14-18

在IMU/DGPS辅助航空摄影测量生产中,布设检校场的作用、检校场如何布设、飞行的频率以及飞行中的注意事项等一直是国内外众多学者专家积极讨论的内容.文中对检校场所起的作用进行了系统分析,提出了检校场的布设方案,并进行了大量的实测数据实验,探讨了上述问题.  相似文献   

利用归一化植被指数研究植被分类、面积估算和不确定性分析的进展   总被引：18，自引：1，他引：17  

陈朝晖  朱江  徐兴奎 《气候与环境研究》2004,9(4):687-696

植被在全球生态系统中扮演着重要的角色.陆地生态系统与全球气候变化也是息息相关.利用遥感资料对植被进行分类,并估算植被覆盖面积已成为一个极具活力的研究方向,其结果的准确度及误差来源受到不同程度的重视.作者对利用遥感资料研究植被分类,进行面积估算,分析其不确定性三个方面的研究进展进行了回顾和讨论,探索进一步利用遥感资料分析植被信息的可行性.  相似文献   

Wide‐area estimates of evapotranspiration by red gum (Eucalyptus camaldulensis) and associated vegetation in the Murray–Darling River Basin,Australia          下载免费PDF全文

Pamela L. Nagler  Tanya M. Doody  Edward P. Glenn  Christopher J. Jarchow  Armando Barreto‐Muñoz  Kamel Didan 《水文研究》2016,30(9):1376-1387

Floodplain red gum forests (Eucalyptus camaldulensis plus associated grasses, reeds and sedges) are sites of high biodiversity in otherwise arid regions of southeastern Australia. They depend on periodic floods from rivers, but dams and diversions have reduced flood frequencies and volumes, leading to deterioration of trees and associated biota. There is a need to determine their water requirements so environmental flows can be administered to maintain or restore the forests. Their water requirements include the frequency and extent of overbank flooding, which recharges the floodplain soils with water, as well as the actual amount of water consumed in evapotranspiration (ET). We estimated the flooding requirements and ET for a 38 134 ha area of red gum forest fed by the Murrumbidgee River in Yanga National Park, New South Wales. ET was estimated by three methods: sap flux sensors placed in individual trees; a remote sensing method based on the Enhanced Vegetation Index from MODIS satellite imagery and a water balance method based on differences between river flows into and out of the forest. The methods gave comparable estimates yet covered different spatial and temporal scales. We estimated flood frequency and volume requirements by comparing Normalized Difference Vegetation Index values from Landsat images with flood history from 1995 to 2014, which included both wet periods and dry periods. ET during wet years is about 50% of potential ET but is much less in dry years because of the trees' ability to control stomatal conductance. Based on our analyses plus other studies, red gum trees at this location require environmental flows of 2000 GL yr^?1 every other year, with peak flows of 20 000 ML d^?1, to produce flooding sufficient to keep them in good condition. However, only about 120–200 GL yr^?1 of river water is consumed in ET, with the remainder flowing out of the forest where it enters the Murray River system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Water body mapping method with HJ-1A/B satellite imagery     

Shanlong Lu  Bingfang WuNana Yan  Hao Wang 《International Journal of Applied Earth Observation and Geoinformation》2011

This paper proposes an integrated water body mapping method with HJ-1A/B satellite imagery, the CCD (charge coupled device) data of the Chinese environmental satellites that were launched on September 6th, 2008. It combines the difference between NDVI and NDWI (NDVI–NDWI) with SLOPE and near-infrared (NIR) band. The NDVI–NDWI index is used to enhance the contrast between water bodies and the surrounding surface features; the topographic SLOPE is used to eliminate the mountain shadow; and the NIR band is used to reduce the effects of artificial construction land. The objectives are evaluating the potential of the HJ-1A/B imagery on water body monitoring, and proposing ideally mapping method. The test study results indicated that the NDVI–NDWI index is superior to the single index of NDVI and NDWI to enhance the contrast between water bodies and the rest of the features. On the basis of the accurately mapped water bodies in the HJ-1A/B CCD images of the study area, we conclude that the HJ-1A/B multi-spectral satellite images is an ideal data source for high spatial and temporal resolution water bodies monitoring. And the integrated water body mapping method is suitable for the applications of HJ-1A/B multi-spectral satellite images in this field.  相似文献   

High positive correlation between soil temperature and NDVI from 1982 to 2006 in alpine meadow of the Three-River Source Region on the Qinghai-Tibetan Plateau     

Weixin Xu  Song Gu  XinQuan Zhao  Jianshe Xiao  Yanhong Tang  Jingyun Fang  Juan Zhang  Sha Jiang 《International Journal of Applied Earth Observation and Geoinformation》2011

Using satellite-observed Normalized Difference Vegetation Index (NDVI) data and Rotated Empirical Orthogonal Function (REOF) method, we analyzed the spatio-temporal variation of vegetation during growing seasons from May to September in the Three-River Source Region, alpine meadow in the Qinghai-Tibetan Plateau from 1982 to 2006. We found that NDVI in the centre and east of the region, where the vegetation cover is low, showed a consistent but slight increase before 2003 and remarkable increase in 2004 and 2005. Impact factors analysis indicted that among air temperature, precipitation, humid index, soil surface temperature, and soil temperature at 10 cm and 20 cm depth, annual variation of NDVI was highly positive correlated with the soil surface temperature of the period from March to July. Further analysis revealed that the correlation between the vegetation and temperature was insignificant before 1995, but statistically significant from 1995. The study indicates that temperature is the major controlling factor of vegetation change in the Three-River Source Region, and the currently increase of temperature may increase vegetation coverage and/or density in the area. In addition, ecological restoration project started from 2005 in Three-River Source Region has a certain role in promoting the recovery of vegetation.  相似文献   

南亚高压和西太平洋副热带高压的变化及其与降水的联系   总被引：5，自引：1，他引：4       下载免费PDF全文

陈永仁  李跃清  齐冬梅 《高原气象》2011,30(5):1148-1157

利用NCEP/NCAR再分析资料和我国160站月降水资料,分析了南亚高压与西太平洋副热带高压（下称西太副高）在不同时间尺度上的关系及对降水的影响。结果表明,南亚高压东伸指数存在3～6年、10～15年和20年以上的周期变化,西太副高西伸指数存在3～6年和20年以上的周期变化。其中在3～6年尺度和10～15年尺度上,南亚高...  相似文献   

基于孔隙结构的酸性火山岩储层流体识别方法研究   总被引：6，自引：0，他引：6       下载免费PDF全文

覃豪  李洪娟  杨学峰  王春燕 《地球物理学报》2011,54(2):422-427

酸性火山岩山于成岩矿物类型多样,孔隙结构复杂,电阻率普遍较高,应用常规的中子-密度测井曲线交会和电阻率的高低已经不能判断储层流体性质.在天然气的测井响应特征分析基础上,应用三孔隙度组合、横纵波时差比值、核磁共振及综合参数识别流体性质.应用结果表明这些方法只能识别含气储层,对于气水同层的识别效果并不好.电阻率对储层流体性...  相似文献   

南海共轭大陆边缘构造属性的综合地球物理研究   总被引：11，自引：5，他引：6       下载免费PDF全文

郝天珧  徐亚  孙福利  游庆瑜  吕川川  黄松  丘学林  胡卫剑  赵明辉 《地球物理学报》2011,54(12):3098-3116

利用南海最新的重磁资料,在岩石物性分析和全海域分带变倾角化极磁异常反演磁性基底分布的基础上,选择6条典型剖面拟合反演其密度与磁性结构,在此基础上进行了深部结构的对比分析.反演中尽可能以海底地震仪探测数据(OBS)、多道地震等结果作为约束,其中FF'剖面层速度分析是利用“南海大陆边缘动力学及油气资源潜力”973项目200...  相似文献   

Characterization of organic matter in sediment cores of the Todos os Santos Bay, Bahia, Brazil, by elemental analysis and 13C NMR     

Costa AB  Novotny EH  Bloise AC  de Azevedo ER  Bonagamba TJ  Zucchi MR  Santos VL  Azevedo AE 《Marine pollution bulletin》2011,62(8):1883-1890

The impact of human activity on the sediments of Todos os Santos Bay in Brazil was evaluated by elemental analysis and ¹³C Nuclear Magnetic Resonance (¹³C NMR). This article reports a study of six sediment cores collected at different depths and regions of Todos os Santos Bay. The elemental profiles of cores collected on the eastern side of Frades Island suggest an abrupt change in the sedimentation regime. Autoregressive Integrated Moving Average (ARIMA) analysis corroborates this result. The range of depths of the cores corresponds to about 50 years ago, coinciding with the implantation of major onshore industrial projects in the region. Principal Component Analysis of the ¹³C NMR spectra clearly differentiates sediment samples closer to the Subaé estuary, which have high contents of terrestrial organic matter, from those closer to a local oil refinery. The results presented in this article illustrate several important aspects of environmental impact of human activity on this bay.  相似文献