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201.
河北沧州黑龙港地区粮食作物生产潜力估算 总被引:15,自引:0,他引:15
本文采用屡次分析法,运用1∶10万TM卫星图象对黑龙港类型区(沧州区域为例)农业生产水平类型划分的结果,分析计算了该区各种类型土地(高、中、低产田)的各级生产潜力和粮食作物生产潜力。得出沧州区域提高粮食生产潜力着眼点在高、中产田,主要措施是增加能量投入,合理用水,改良土壤。 相似文献
202.
四川省农用土地资源卫星遥感宏观监测技术方法研究 总被引:6,自引:1,他引:6
通过对土地利用类型区的分层技术、卫星遥感抽样技术、样方调查方法、数据库建立、数据汇总与外推方法、数理统计分析与精度评估等6个专题的重点研究,探索出一套四川省农用土地利用现状卫星遥感抽样调查与监测的技术方法。该技术方法实用性和可操作性较强,已在四川省实施应用,完成了1∶10万农用土地利用现状抽样调查。土地利用类型区分为7个层25个亚层,抽样数为118个,样方大小为10km×10km(即100km2),实际抽样率为2.0%。应用结果表明:在合理分层的基础上,采用卫星遥感抽样与地理信息系统相结合的方法,能满足土地利用现状宏观调查与监测的精度要求。 相似文献
203.
Wolf von Tümpling Peter Zeilhofer Ulrich Ammer Jürgen Einax Rolf -D. Wilken 《Environmental science and pollution research international》1995,2(4):225-228
As in many other parts of the world, gold is produced in the surface mining region of Poconé, Mato Grosso, Brazil, using mercury.
The goal of this investigation was to estimate the amount of mercury in certain tailings and to determine the area of the
land that has been contaminated by the gold mining operations. Mercury concentrations from 2 to 495 ng/g (dw) were determined
in the tailing materials. It was observed that only isolated sites were acting as central points of contamination. Using digital
Landsat satellite data (The-matic Mapper) and aerial photos, the sites degraded by the mining were classified, and their total
area was estimated to be 12.3 km2 in the region of Poconé. It was estimated, that 4.9 km2 were occupied by the contaminated tailings. The mean height of the pile slags was determined to be 4.5 m. From the experimentally
calculated average density of the material in the tailings, 2.01 g/cm3, the total mercury content in the piles of tailings was estimated to be 1600 ± 350 kg. 相似文献
204.
对覆盖江苏全省的SPOT5高分辨率卫星遥感数据进行了空间融合处理,建立2.5m分辨率数字正射影像库(DOM),为突发性环境污染事故应急处理提供重要的空间数据服务,可有效指导环境应急监测点位布设、人员疏散,防止污染物对河流、空气、土壤的生态破坏,提高环境预警与应急响应能力。 相似文献
205.
Curtis B. Barrett 《Journal of the American Water Resources Association》1993,29(6):933-938
ABSTRACT: The National Oceanic and Atmospheric Administration is developing a river forecast system for the Nile River in Egypt. The river forecast system operates on scientific work stations using hydrometeorological models and software to predict inflows into the high Aswan Dam and forecast flow hydrographs at selected gaging locations above the dam The Nile Forecasting System (NFS) utilizes satellite imagery from the METEOSAT satellite as the input to the forecast system. Satellite imagery is used to estimate precipitation over the Blue Nile Basin using five different techniques. Observed precipitation data and climatic statistics are used to improve precipitation estimation. Precipitation data for grid locations are input to a distributed water balance model, a hill slope routing model, and a channel routing model. A customized Geographic Information System (GIS) was developed to show political boundaries, rivers, terrain elevation, and gaging network. The GIS was used to develop hydrologic parameters for the basin and is used for multiple display features. 相似文献
206.
Marco Ferretti Emilia Barbolani Paolo Grossoni Romano Gellini Francesco Pantani 《Chemistry and Ecology》1993,8(1):1-10
One year old needles of both healthy and damaged silver fir and Norway spruce from the area of Trento (Northern Italy) were observed by SEM. Needles of damaged trees show quite evident structural alterations of epidermis, expecially epicuticular waxes. Roots and needles of both fir and spruce are also tested for their metal content. Evidence is reported of an increasing concentration of Fe, Mg and Ca in roots of plants grown on alkali soil. Ca, and to a lesser extent Fe, Al and Pb, appears to be more present in old needles, whereas K and Mg exhibit higher amounts in young needles. Some indications are found between damage and the content of some metals such as Mg and Mn in needles. 相似文献
207.
In the project of the solar systems, the values of the solar radiation of a region must be known. The global solar radiation measurements are performed by the Turkish Meteorological Service in Turkey, while the diffuse solar radiation measurements are unavailable. In this study, some new models for predicting the monthly average daily diffuse solar radiation on a horizontal surface for Erzincan, Turkey are developed using satellite data. The evaluation of the models is carried out with the statistical analysis methods of mean bias error (MBE), root mean square error (RMSE) and correlation coefficient (r). The results are proved that the correlation equations obtained in here can be used to forecast diffuse solar radiation reasonably well. 相似文献
208.
QuickBird multispectral satellite imagery was evaluated for distinguishing giant salvinia (Salvinia molesta Mitchell) in a large reservoir in east Texas. The imagery had four bands (blue, green, red, and near-infrared) and contained
11-bit data. Color-infrared (green, red, and near-infrared bands), normal color (blue, green and red bands), and four-band
composite (blue, green, red, and near-infrared bands) images were studied. Unsupervised image analysis was used to classify
the imagery. Accuracy assessments performed on the classification maps of the three composite images had producer’s and user’s
accuracies for giant salvinia ranging from 87.8 to 93.5%. Color-infrared, normal color, and four-band satellite imagery were
excellent for distinguishing giant salvinia in a complex field habitat. 相似文献
209.
环境一号卫星CCD数据在太湖蓝藻水华遥感监测中的应用 总被引:6,自引:1,他引:5
利用环境一号卫星(HJ-1)CCD数据,对太湖水华进行遥感监测,并比对同时相的EOS/MODIS卫星遥感数据。结果表明,HJ-1星CCD数据具有优于EOS/MODIS数据的蓝藻水华识别能力,并有良好抗云层干扰能力,适合用于太湖蓝藻水华应急监测。 相似文献
210.
环境一号卫星环境应用系统工程及其关键技术研究进展 总被引:3,自引:1,他引:2
简介长达11年的国家重点项目“环境一号卫星环境应用系统工程及其关键技术研究”的核心内容及其重要研究成果,对环境一号卫星系统需求分析、设计理论、研制发射和运行应用全过程进行了完整的研究与实践,为环境一号卫星系统的建设、应用和业务运行奠定了重要基础。 相似文献