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931.
Classifying tree species in a northern mixed forest using high-resolution IKONOS data 总被引:4,自引:0,他引:4
The high-spatial-resolution IKONOS satellite is now operating as a resource and disaster monitor, after a successful launch in September 1999. The ground resolution of the IKONOS panchromatic band is about 1m, the greatest of any satellite. The objectives of this study were to verify the extent to which high-resolution IKONOS data can be used to classify tree species. A field survey and image analysis study used IKONOS imagery to classify 21 species in mixed stands of deciduous and conifer species with the following results: (1) The panchromatic and multi-spectral bands 4, 3, and 2 were useful for classifying tree species owing to the great difference in the reflectance values between tree species. (2) Some groups, for which there were significant differences among species, were identified using Tukeys multiple comparison test; conifers and some broadleaved trees were identified correctly more often than other species. (3) A random selection of validation pixels showed that the overall classification accuracy was 62%. The classification accuracy of broadleaved trees was a little low, ranging from 40% to 63%, while that of conifers exceeded 70%. (4) The overall accuracy of the classification at the genus level improved by 4% more than the species level. The misclassification of broadleaved trees was due to the similar spectral characteristics of species in the same genus. 相似文献
932.
Chris J. Johnson Nancy D. Alexander Roger D. Wheate Katherine L. Parker 《Forest Ecology and Management》2003,180(1-3):241-248
Woodland caribou (Rangifer tarandus caribou) are sensitive to changes in understory vegetation resulting from forest harvesting and are, therefore, of special concern for foresters and habitat biologists. Effective management of this species requires reliable habitat inventories which, because of the large heterogeneous areas over which caribou range, can be costly. We used Landsat Thematic Mapper (TM) imagery and digital elevation data to identify 23 vegetative cover types across the 5100 km2 range of the Wolverine caribou herd of northcentral British Columbia, Canada. The classification was augmented with available geographical information system (GIS) data for a total of 27 cover types. We achieved an overall accuracy of 76.7% based on known ground samples; however, accuracy varied according to cover type. Considering the size of the study area, the procedure we employed was relatively cost effective and efficient. We discuss the advantages of such an approach for wildlife-habitat studies reliant on large-scale vegetation maps. 相似文献
933.
黑龙江省海伦市于2004年进行森林分类区划界定,经过多名专业人员严密的组织和精心的工作,于2004年3月20日顺利完成了全部工作。本区划界定首先分析了生态环境特点,然后确定了区划比例和界定原则,并绘制了区划界定图,最后对区划界定工作提出了建议。 相似文献
934.
王世彰 《中南林业科技大学学报(自然科学版)》2003,23(1):64-67
报道发现于我国长白山的弹尾目 (Collembola)中隶属于 10科 15属的 2 5种新记录种 ,观察标本保存在北京自然博物馆 相似文献
935.
结合特征参数间相关性矩阵与木材纹理自身的特征,从灰度共生矩阵的11个特征参数中提取5个较独立的特征参数.利用可分性判据确定适于描述木材纹理的灰度共生矩阵构造因子取值(d=2,g=16). 相似文献
936.
685,000 ha of Pinus radiata(D. Don) plantations in Australia werecategorized using a matrix of mean annualrainfall, rainfall regime and Parent Rock Codefrom a Technical Soil Classification. Datawere obtained from a number of differentorganizations which in total managed nearly allthe Australian P. radiata plantations. The selected characteristics were those whichcould be obtained at an acceptable level ofconfidence from all sources. Such acharacterization of plantation sites provided asystem for utilization of technical informationand extrapolation of research results and alsoa basis for the development of Site SpecificManagement systems. Analysis of theinformation indicated the high degree ofvariability of environments in whichplantations have been established withinAustralia and also the distinctive nature ofindividual regions. Such differences betweenareas make extension of silvicultural andrelated information difficult from one area toanother without appropriate validation. Abroad comparison with 1.26 million hectares ofP. radiata plantations in New Zealandindicated only a small overlap of areas of sitetypes between Australia and New Zealand. Assumptions derived in one location on thesites, characteristics, models and/or genotypeswould require significant testing beforeconfident application could be undertaken toanother area. The value of a Site SpecificManagement system for research planning andapplication of research and operational resultswas demonstrated from analysis of a series ofexperimental trials assessing application offertilizer after thinning and from evaluationof soil carbon in P. radiataplantations. 相似文献
937.
对山西省林木资源概况及主要类型的划分进行了详细叙述,提供了诸多林木价值的核算方法,根据山西省林木资源现状采用了市场价倒算法确定林木价格,并在此基础上对山西省林木资源价值进行了核算,计算出山西省林木资源的总价值。 相似文献
938.
关于福建省树种结构调整问题的几点思考 总被引:12,自引:4,他引:12
根据福建省森林资源现状、结构特点提出关于树种结构调整必要性、树种结构调整必须考虑的几个问题 ,同时着重提出杉木、马尾松、阔叶树等几个主要树种的结构调整的方向、途径以及现有资源的合理利用等。 相似文献
939.
Using quantification theory I, an analysis of the relation of soil water and qualitative factors, such as, slope degree, slope
aspect, slope position, and soil in Wangjiagou watershed area has been done. The study aims to quantify the factors influencing
soil water, the descending order of the factors being the slope aspect, soil, slope degree, and slope position, thereby scientifically
facilitating division of afforestation site types and afforestation site products digitally on geographical information system
(GIS).
__________
Translated from Journal of Northwest Forestry University, 2006, 21(3): 184–188 [译自: 西北林学院学报, 2006, 21(3): 184–188] 相似文献
940.
我国1964—1979年间引进的油橄榄餐用品种均已开花结果。经对其果实经济性状的测定表明,大部分品种保持了原有的特性,突出特点是果实大、果肉率高。典型的餐用品种有“戈达尔”、“贝拉”、“软阿斯”、“小平果”、“卡蒙·小平果”、“皮肖利”、“坦彩”以及我国选育的“中山_(24)”、“城固_(22)”。这些品种的果实单粒重量为4.58—9.02g;果肉率85.1—89.9%。果肉中含有多种有益于人体健康的营养成分:可溶性糖类占1.5—8.7%,粗蛋白3.8—11.9%(其中包括7种人体必需的氨基酸630—1280 mg/100g、6种非必需的氨基酸780—2450mg/100g);矿质元素1.7—2.2%(包括Ca、Mg、K、Na、P常量元素和Zn、Mn、Cu、Fe微量元素);以及7.9—15.8%的橄榄油。 研究初步确定了我国油橄榄餐用品种果实的分类标准;不同果实加工产品类型(青果型、黑果型)的适时采收期。 相似文献