二类调查区划固定小班的浅探

所谓固定小班就是二类调查小班（经理小班）现地定界，即图上小班线现地伐开、挂号、立标。 实行固定小班是二、三类调查结合的途径之一，利于生产，利于经营管理。天保工程及分类经营的现地定界给小班固定化提供了方便条件。 区划固定小班应在天保工程及分类经营划分的小区基础上区划小班。也就是以小区为单元，在小区内划小班。商品林根据小班划分条件区划小班；生态公益林可适当放宽，如果地类、优势树种（组）、起源、龄组、郁闭度级、林冠下造林等条件一致（其它条件无差别或差别不大，可不考虑）的情况下，可划一个小班，面积可放宽到…     

关于提高小班蓄积量目测水平的探讨

分析了“角规测树”在森林资源二类调查中的应用限制，对提高小班蓄积量目测水平的途径进行了概括总结，并提出用小班目测练习取代传统的标准地练习之新观点。     

改革小班区划、完善森林资源档案管理

通过对森林资源档案建立在调查小班上存在问题的分析，说明了资源档案不能建立在调查小班基础上，必然改革小班区划，使森林资源档案建立在固定小班基础上，使规划设计调查和资源建档有机结合起来。     

森林资源规划设计调查中小班区划方法探讨

针对目前森林资源规划设计调查中小班区划方法存在的问题，提出了连续小班区划方法，并分析了连续小班区划方法的优点及应用前景。     

山东省林地保护利用规划一张图建设精度分析

从基础数据、小班图形数据采集二个方面，对山东省林地保护利用规划一张图建设小班图形数据精度进行了系统、全面的分析。     

Photoshop软件在基层林业工作中的应用

笔者通过不断摸索探讨,掌握了使用Photoshop软件进行图纸拼接、小班勾绘落界、小班注记、小班面积求算、林业专项图纸的制作等技术,并验证使用该软件求算小班面积,精度可达99.9%以上。本文进行具体介绍,以促进该项技术在林业基层实践中应用推广。     

可变概率小班抽样方法应用于国营林场资源调查的试验和讨论

一、可变概率小班抽样法定义将总体按特定的组合方式划分为若干小班,小班不等大,以小班作为抽取单位。其抽样概率与小班面积大小成比例。再在抽出的小班中,对小班进行详查,以其数据估测总体,求得总体平均数,总量及其抽样误差的无偏估计。     

基于融合影像和林相图的林业资源动态监测

以福建省永安市两乡镇的林业小班图层为基础，利用“资源二号”影像与TM影像的融合，有效地增强了不同林地之间的差异和林地之间的界线；并利用1996年林相小班图层，通过属性选择提取不同林地小班专题，转换成感兴趣区域(AOI)。以AOI限制分类范围对融合图像进行分层监督分类，直接得到不同林地的动态变化区域，从而减小林相图更新的工作量。     

GPS和ArcGIS在基层林业调查中的应用方法

该文详细阐述了在基层林业调查中,利用GPS手持定位导航仪和ArcMap地理信息软件,将调查小班坐标数据导入软件系统,进行电脑色绘小班,形成小班图和小班表的方法,做到提高工作效率,节省经费,使林业经营管理工作更趋科学化。     

资源建档中调查小班与经营小班矛盾的协调

森林档案中设立的小班档案卡片是以二类调查中区划的调查小班为单位,按各有关调查因子逐项登载记录的。建档后,每年的资源消长变化都在小班档案卡片上进行调整,并在此基础上进行每年度的森林资源统计工作。但是,由于以往二类调查小班区划比较粗放,主要按土地种类、林分特征和立地条件进行划分,小班线不受林班内地貌地性线的影响,在林区内无明显界限,无法准确区分。而生产单位为满足经营的需要,方便采伐利用、更新抚育、幼林管护等,常常按一沟一坡,同一地类、同一作业条件下不翻山跨岭的原则划分出生产经营小班。很显然,调查经营小班与生产中的经营小班往往不一致。因此,用调查小班建档后,就会出现经营小班与调整小班不相符的情况,进而导致建档工作不能正常进行下去。这个问题也恰恰是许多单位森林经营档案管理坚持不下去,半途而废的重要原因之一。 如今,在调查小班与经营小班之间的矛     

利用ArcGis实现森林资源管理“一张图”线转面的方法探讨

探讨了如何利用Arcgis平台将辽宁省的林带(线状)图斑批量转入小班(面状)图斑中,主要采用了Buffer、Union、Delete Identical、Dissolve、Identity、Load等功能,将林带(线状)图斑逐步转为面状,并区划到小班(面状)图斑,以实现辽宁省森林资源管理“一张图”线面的统一。     

大理州中低产林现状及改造对策

实施中低产林改造是提高森林资源整体质量水平的有效措施,是改变大理州林业"大资源、小产业、低效益"现状的必然选择,阐述大理州中低产林资源情况、改造的必要性,分析中低产林改造中存在的主要问题,提出7个方面的对策。     

Effects of multiple factors on plant diversity of forest fragments in intensive farmland of Northern Portugal

The joint and independent effects of dominant tree species, forest patch spatial attributes, and forest structure and management as drivers of plant species richness and composition in small forest patches scattered within an intensive agricultural landscape were addressed.In a landscape with scattered urban and intensive dairy agricultural areas in north-west Portugal, within which small forest patches (dominated by pines, eucalypts, or both) represent semi-natural habitat islands, 50 small forest patches, with areas ranging between 0.3 and 3 ha, were selected and surveyed for vascular plant diversity, within dairy farming landscape mosaics dominated by annual forage crops. Explanatory variables were composed of three datasets derived either from GIS mapping or field observations: forest type (dominant tree species), forest patch spatial attributes (patch area and shape index), and measures of forest management and structure (diameter at breast height, tree density per hectare, and percentage cover of vegetation strata). Variations in these forest patch attributes were assessed across forest types, and related to measures of plant diversity (total, native, alien, woody, and herbaceous species richness). Redundancy analysis with variance partitioning was applied to evaluate the joint and independent effects of the three sets of variables on species assemblages. The recent shift in canopy dominance from pine to eucalypt observed in the region appears to be related to a (nonsignificant) tendency for the increase of patch area and to the decrease of patch complexity, as well as several changes in forest structure and management, expressed as a trend to denser tree canopies and lower cover of understory plants. Dominant tree species and attributes related to forest structure and management were the most important factors determining plant diversity. The joint effect of the dominant tree species and forest structure and management resulted in lower levels of plant species richness in eucalypt plantations. These were also more prone to invasion by alien species, probably due to decreased biotic resistance from unsaturated native plant assemblages. Our results draw attention to the importance of dominant tree species and management practices for the maintenance of plant diversity levels (species richness and composition) in dairy landscape mosaics, highlighting the importance of the remnants of semi-natural forests as refuges for plant diversity in the landscape context. Nonetheless, forest plant diversity could further be fostered by promoting naturalness of pine stands and the regeneration of native oak woodlands in some forest areas. This would also diversify the range of ecosystem services that could be provided by forest areas in these peri-urban farmlands.     

The effects of forest patch size and ownership structure on tree stand characteristics in a highly deforested landscape of central Poland

Forest structure is influenced by the origin, history and manner of forest management. All these aspects may affect the occurrence of many forest dwelling organisms. We investigated the simultaneous impact of forest patch size and ownership structure on selected forest characteristics in central Poland. We sampled stand composition, the DBH of particular tree species, basal area, species number and species diversity in all 32 forest patches found in a farmland-dominated area of 150 km². Forest ownership status was linked to patch size: large patches were state-owned and small ones were private. Ownership status also affected the average DBH and basal area of all tree species pooled, with lower DBH and basal area found in private forests. The share of deciduous trees was negatively affected by forest size, while pine was positively affected, which could suggest that forest management and economic interests may be related to this factor. The share of non-native species was higher in state forests. Our results showed that forest patch size could be associated with its ownership status, which is commonly ignored in research on the relationship between forest size and species occurrence. Historical as well as sociological aspects related to private forests in Poland are also presented.     

Forest patches in Imperata grassland and prospects for their preservation under agricultural intensification in Northeast Luzon, The Philippines

Frequent burning and grazing and cultivation of cash crops increasingly threaten forest patches in hilly grassland in Northeast Luzon, yet their importance as a resource with multiple environmental functions and forest products persists. The aim of this study is to identify different types of forest patches, and their condition under present land-use intensification, and discuss prospects for their integration into sustainable local farming systems. Five types of forest patches are distinguished, both natural and planted ones, including rows of trees, woody patches, gallery forests, hill-slope forests and homegarden conglomerations. Natural woody patches and gallery forests in Imperata grassland are subject to degradation and land-use conversion under conditions of agricultural intensification. Woody patches in grassland affected by frequent burning and grazing cover small areas (66% below 50 m² as opposed to 28% in protected grassland) and contain relatively few woody plant species (25 woody species in total as opposed to 82 where protected). Yet where well managed, they may provide a variety of products for sale and subsistence, covering emergency needs and giving off-season cash income to rural communities. Moreover they serve like the gallery forest various ecological functions, carrying valuable indigenous tree species, retaining soil base nutrients, providing a continuous supply of organic matter and intercepting fine earth soil particles removed from bare surfaces. It is suggested that forest-patch management systems may be developed, taking into account both patch diversity and the diverse needs of rural communities, and to strengthen existing and undervalued functions of forest patches as permanent elements in an agricultural landscape.This revised version was published online in November 2005 with corrections to the Cover Date.     

海南霸王岭热带山地雨林森林循环与群落特征研究

以海南霸王岭1hm^2热带山地雨林的网格样方调查数据为基础，首先对全林分的群落特征进行了分析，然后以森林循环理论为指导，研究了热带山地雨林的种群与群落特征。结果表明：热带山地雨林中不同生活型的树种在利用垂直和水平生态资源上是相对分离的，绝大部分的灌木或小乔木树种的水平生态位宽度较大，垂直生态位宽度较小，中、大乔木则正好相反，而那些低密度、稀有种的生态位宽度最小。随森林循环过程的进行，各树种在不同阶段斑块内出现的频度也会发生相应的变化。霸王岭热带山地雨林中占优势的乔灌木树种大都呈聚集分布的格局，个体数中等的树种大都呈均匀分布的格局，而那些个体数少的低密度种则大都呈随机分布的格局。随着森林循环过程的推进，每个树种所拥有的个体数和所占据的面积是逐渐减少的。森林循环不同阶段内的树种数随着个体数的增加呈现出逐渐减少的总趋势，尤其是由单个体和双个体所对应的物种数较多，3个以上个体对应的树种数则呈现出明显的下降。不同斑块之间组成相似性的大小在一定程度上表明了热带山地雨林森林循环斑块动态的连续性，相邻阶段斑块之间的相似性大于不相邻阶段斑块。以森林循环阶段为基础计算的生态位宽度表明，热带山地雨林中大部分低密度的树种或只集中分布在森林循环的少数阶段斑块内的树种对不同阶段斑块的生态资源利用较少，而那些在森林循环的不同阶段都出现，且个体数或断面积中等的树种，对森林循环不同阶段斑块的生态资源利用较大。     

八英庄林场砬沿沟流域森林景观变化分析

为更好地实现八英庄林场森林资源的优化配置,以河北省木兰围场国有林场管理局八英庄林场2010年和2015年2期地形图、遥感图像及二类调查数据为基础,运用ArcGIS10.0和Fragstats4.2软件,对砬沿沟流域森林景观变化进行分析。砬沿沟流域按一级景观分类划分,斑块类型共5类,有林地斑块面积由473.95hm~2增加为500.88hm~2,其他斑块面积相对减小;有林地的景观形状指数、散布与并列指数减小,分别由3.008 1、59.106 6降为2.481 6、49.060 4;景观多样性由0.426 9减小为0.233 4,说明各斑块的聚集程度有所增加,各斑块之间的连通性有所提高。砬沿沟流域按二级景观分类划分,在有林地类型中,2010年和2015年斑块类型都为5类,到2015年山杏林斑块消失,新增云杉林斑块;2010至2015年华北落叶松林斑块面积、斑块景观形状指数均增加,山杨林斑块面积、斑块景观形状指数均减小。砬沿沟流域森林景观香农多样性指数由1.602 7降为1.389 2。除去一级景观分类中有林地斑块破碎度减小,其他无论是一级景观分类还是二级景观分类,各斑块破碎度都有不同程度的增加,说明近5a一级、二级斑块在总数上有所增加,并且增加的斑块相对独立,并不连续。     

Retention of native vegetation within the plantation matrix improves its conservation value for a generalist woodpecker

The suitability of plantation monocultures for the conservation of forest animals is an issue under continous debate. The adaptability of forest dwellers and the forest management regime seem to play key roles. In this study, I investigated the habitat selection of a generalist bird, the great spotted woodpecker (Dendrocopos major), within a pine (Pine spp.) monoculture, as well as the importance of the native habitat features within the pine matrix for the species’ conservation. I compared 52 plots with woodpecker presence against 121 plots where the species was absent, as well as 68 nest-trees against 90 random ones. Regression analyses were used to investigate the habitat attributes involved in the habitat selection. Although the great spotted woodpecker is considered a generalist forest dweller, it shows a marked habitat selection. Based on presence/absence records, the woodpecker prefers well-forested patches with high levels of tree diversity and with good coverage of a secondary species such as the strawberry tree (Arbutus unedo). To excavate their nests, woodpeckers select large trees in patches where other trees are also larger, rejecting patches with a high number of small trees. The most striking conclusion from this work is the preference shown for native trees, especially Portuguese oaks (Quercus faginea), as nest-trees. This is noteworthy because native trees are smaller and they are surrounded by smaller trees than pines. These findings support that woodpecker conservation benefits from an increase of habitat heterogeneity, particularly by the retention of native woodland patches within the plantation matrix.     

南阳城市森林景观格局分析

森林景观格局是城市生态建设和规划的重要内容[1].城市森林绿地是最重要的城市生态用地,对维持良好的城市生态环境具有至关重要的作用,也是改善和调节城市环境的最重要的生态源地.由于城市与城市郊区在空间上邻接,城郊的森林绿地也对城市发挥着重要的生态作用[2-3].     

Analysis of temporal changes in land cover and landscape metrics of a managed forest in the west Black Sea region of northern Turkey: 1970–2010

Forest structure changes continuously by natural and anthropogenic effects. Because the level of goods and services provided by forest ecosystems are related to this structure, some attributes have to be controlled while they are being managed. In this paper we describe the long-term temporal changes in land area and landscape metrics related to different land uses of a managed forest in Turkey. The study was carried out for the Daday Forest Planning Unit located in the west Black Sea region of northern Turkey. The total area is 16,813 ha and besides wood production, it is managed for erosion control, public health, aesthetics, and recreation. Stand type maps that were constructed in 1970, 1989, 1999, and 2010 were used in this analysis. Transition matrixes that illustrate area changes among cover types and temporal changes on some landscape metrics were obtained using Geographic Information Systems. Stands were separated into small patches, and thus the number of patches increased nearly two-fold between 1970 and 2010. The total forest edge increased and through the associated fragmentation, the amount of core forest area decreased at the landscape scale. Landscape metrics were applied to digitized versions of historical maps to assess how forest area changed. Human use of the land has changed, forest management practices have evolved, and these along with natural forest growth have contributed to interesting changes in landscape character.