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为探索南方集体林区生态公益林经营方法,实现科学、高效的生态公益林管理模式,本文以贵州省习水县生态公益林为研究对象,对习水县生态公益林进行经营类型划分。在分析习水县生态公益林的特点的基础上,选择森林起源、优势树种(组)、立地类型及经营目的为划分依据,应用层次分类法将习水县生态公益林共12338个小班划分成54种经营类型。 相似文献
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永顺县退耕还林试验示范区立地分类及评价 总被引:3,自引:1,他引:3
为解决退耕还林工作中退耕后林种树种配置等有关技术问题,对永顺县勺哈乡试验示范区进行了立地类型划分,并进行了评价。通过运用数量化理论Ⅳ,以坡度、坡位、土层厚度、植物盖度、耕作方式为分类因子,将示范区分成5个立地类型区,即西部以大坡面型农林复合经营为主的立地类型区、顶部低山山原台地立地类型区、中部中上坡带状坡耕地林立地类型区、中部下坡大坡面型农林复合经营坡耕地立地类型区、东部大字报型坡耕地立地类型区等5个立地类型区,并采用专家咨询法对各立地类型进行了评价。 相似文献
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文章论述了辽宁省森林分类经营类型区划分原则及划分结果,并对各类型区建设和林种结构调整提出建议。 相似文献
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文章结合内蒙古大兴安岭林区实际 ,提出了生态公益林的划分办法 ,并针对生态公益林的经营与管理提出建议供参考 相似文献
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1993年,始兴县按照社会经济发展的要求,根据经营目的,将森林划分为生态公益林和商品林两大类,率先实行分类经营。对生态公益林和商品林,采取了不同的政策措施、经营手段、资金投入和采伐利用管理。本文对始兴县的森林区划、分类经营的措施及成效作了较详细的介绍,并针对目前经营管理上存在的问题提出了建议。 相似文献
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鄢前飞 《中南林业调查规划》2002,21(2):7-10
在分析经营类型与小班经营法各自存在利弊的基础上,尝试性地将两种方法在森林分类经营中综合起来并加以改进,提出了分类经营类型-分类经营小班这一新的森林分类经营体系,旨在为分类经营理论和实践上提供指导意义。 相似文献
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人为干扰对额济纳胡杨林群落组成及更新的影响 总被引:3,自引:1,他引:2
额济纳绿洲是我国西北干旱地区的一道强大的生态防线。但由于水资源匮乏和人为干扰影响,绿洲中胡杨林已严重退化。我们认为人为干扰会对胡杨群落的组成和更新造成影响。应用双向指示种分析法(TWINSPAN)和典范对应分析(CCA),从人为干扰角度对额济纳不同地区胡杨群落进行了分类和排序。结果表明:人为干扰会影响群落林下物种多样性和根孽幼苗生长情况;林下物种多样性主要受旅游干扰影响,并与总干扰强度的关系遵循"中度干扰假说";根孽幼苗生长情况与放牧干扰呈负相关,当根孽幼苗数多的时候,一定程度上能够抵御外界干扰对其生长状况的影响;适度的人为干扰可以增加物种多样性,但要保证胡杨林的繁殖更新,需要以消除放牧干扰影响为前提。 相似文献
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Process-based approach to automated classification of forest structures using medium format digital aerial photos and ancillary GIS information 总被引:1,自引:0,他引:1
Filip Hájek 《European Journal of Forest Research》2008,127(2):115-124
The methods of forest inventory data acquisition, based on the analysis of remotely sensed images have been well tested and
implemented during the last decade. The predominant visual interpretation and pixel-based automated techniques are now being
gradually replaced by the object-based image classification at multiple levels. This paper describes an experiment using medium-format
digital aerial imagery for the purpose of automated updating of the existing GIS forest management database (LHPO). The method
emphasises the pre-processing phase, where various image transforms and additional channels i.e. spectral ratios and vegetation
indices (NDVI), low-pass filters, Sobel edge and GLCM (grey level co-occurrence matrix) texture measures are derived from
the original dataset. The layer stack is then transferred into the object-oriented classification environment together with
the existing thematic vector layer, and analysed on three hierarchical object levels. The classification involves the recognition
of the successional stage of forest compartments and the estimation of tree species composition in terms of area coverage.
In addition, age information on the GIS forestry management map can be updated and the spatial distribution of classes corrected
using the multi-scale object relations of the former analysis. The advances of the automated procedure based on sequential
processing of image objects are partially covered. Moreover, aspects of utilisation of the medium-format colour infra-red
images (CIR) as an alternative to traditional aerial photos and very high resolution (VHR) satellite data, were considered. 相似文献
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福建建设中国特色的社会林业研究 总被引:2,自引:1,他引:1
:家庭经营和股份合作制是福建社会林业经营的主要形式。家庭经营是社会林业本质的最直观和典型的实现形式 ,股份合作制也是福建社会林业的重要形式 ,它分为合伙式和要素组合式 2种模式。笔者对家庭经营和股份合作经营模式进行了论述 ,并对其利弊、适用范围和发展方向进行评价与分析 相似文献
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以吉林省汪清林业局金沟岭实验林场为例,介绍了一种基于森林资源二类调查数据的森林景观类型划分方法。划分景观要素类型的因子一级为土地覆盖类型,二级为优势树种组。在景观分类的基础上分析了1987-1997年10a问金沟岭实验林场森林景观空间格局变化。1987年和1997年主要的景观要素类型为针阔混交林、针叶混交林、落叶松林和阔叶混交林,1987年的斑块个数为592块,1997年为946块。斑块个数大幅度增加,反映出森林景观破碎化的趋势。10a问,景观多样性指数和相对丰富度指数降低,优势度指数有所增加。文章对营林活动对森林景观变化的影响进行了初步分析,发现景观类型变化较大的林班也是作业强度比较大的林班,景观斑块数量变化最大的林班也是作业强度比较大的林班。 相似文献
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A new visual inspection method for the classification of wooden plates used in pencil manufacturing is presented. Darker regions in wooden plates indicate the presence of growth rings which are regions of hard wood. Pencils manufactured with these plates are more difficult to sharpen and have a tendency to bend and crack; therefore, these plates are classified as not being adequate for pencil manufacturing. The proposed method is based on the extraction and analysis of the features of the wooden plates using gray level images. The method classifies the plates using the results obtained by an automatic threshold determination based on Shannons entropy. The method was idealized aiming at low computational complexity, i.e., algorithm calculations involving only simple operations such as addition, subtraction, multiplication and division which could be implemented in hardware using VLSI technology or programmable logic devices. The wooden plate is mapped in an optimal number of regions; each region is pre-classified considering some relevant features based on the entropy gray level distribution of the pixels. Information from all regions is combined based on heuristic decision rules, arriving in a pre-classification stage where the regions are labeled in four classes (A, B, C and X). Two decision algorithms have been investigated for the final classification: one based in a co-occurrence matrix considering only a uni-directional horizontal neighborhood of the regions and the second is based on a heuristic method of information reduction considering combinations of the pre-classified regions. The final results obtained by the two algorithms were compared with the classification made by a human expert, demonstrating that the proposed method had very good performance. 相似文献