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1.
2005~2015年永平县北斗乡森林资源变化特征分析 总被引：1，自引：0，他引：1
《林业调查规划》2015,(3)
对永平县北斗乡2005~2015年间森林资源龄组、起源、权属等结构变化情况进行统计分析,结果表明,针叶林和阔叶林以中龄林为主,除核桃面积急剧增加外,针叶林、阔叶林及其它林地面积不同程度减少。2005年针叶林、阔叶林、核桃林地面积比约为0.6∶0.3∶0.1,至2015年变化为0.4∶0.3∶0.3。人工林面积占有林地面积的30.23%,其中核桃占28.54%。林权制度改革后,93.90%的林地使用权属于个人,如何科学合理地利用森林资源,保持生态平衡,是目前林地保护与利用的难点和重点。 相似文献
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3.
关瑞峰 《内蒙古林业调查设计》2020,43(2):94-95,56
利用栅格数据以及Arcgis10.3软件,对呼和浩特市2000—2015年间的土地利用状况通过转移矩阵进行分析。结果表明2000—2015年间各个地类面积由大到小分别是草地、未利用土地、林地、农地、湿地、灌木林地、城乡居民地和水域。草地、城乡居民地、林地为面积增加地类,增加的面积为1000 km^2、2900 km^2、2000 km^2;减少的地类为灌木林地、农地、未利用土地、湿地、水域,减少的面积为200 km^2、1400 km^2、2600 km^2、1400 km^2、300 km^2。 相似文献
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文章以2006年和2016年二类调查数据为依据,通过对林地面积、蓄积的统计分析,探寻呼和浩特市林地面积增减变化规律。分析结果表明:2006—2016年,呼和浩特市土地面积和林地面积呈现双下降趋势,但有林地、灌木林地面积呈增加趋势,有林地、灌木林地分别增加5 539.9 hm^2和7 890.4 hm^2,对森林覆盖率贡献率0.78%;疏林地、未成林地、宜林地面积减少113 624.2 hm^2;林地利用率从22.25%上升到23.23%,提高了0.98个百分点,上升缓慢,乔木林单位面积蓄积量从2006年的55.5 m3/hm^2下降到2016年的48.53 m3/hm^2,减少率12.59%;天然林面积减少13 756.7 hm^2。 相似文献
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以祥云县2006及2016年进行的第三、第四次森林资源规划设计调查数据为依据,利用GIS技术对2期数据进行叠加分析,得到各土地类型面积变化情况。结果表明,有林地是全县占地面积最大的森林资源类型;10年间,祥云县有林地、未成林造林地、无立木林地增加;疏林地、灌木林地、苗圃地、宜林地减少。在发生面积转移的类型中,以其他类型向有林地转化为主。在分析变化原因的基础上,提出建设"数字林业",采取科学的森林经营和管理措施,合理开发林下资源等林业发展建议。 相似文献
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为了解林下灌木层生物量和碳密度变化特征,基于森林火灾风险普查样地调查与森林资源一张图数据,对福州市乔木林主要森林类型林下灌木层生物量和碳密度进行研究。结果表明:(1)福州市乔木林林下灌木层总生物量169.37×10^(4)t,总碳储量为79.61×10^(4)t,平均碳密度达1.49 t/hm^(2);(2)不同森林类型林下灌木层碳密度1.11~1.94 t/hm^(2),其大小依次为人工阔叶林>天然阔叶林>人工马尾松林>天然针叶林>人工针叶林>人工杉木林;(3)不同森林类型林下灌木层单位面积生物量、碳密度随着乔木层郁闭度的增加总体呈明显减少趋势,生物量大小为低郁闭度>中郁闭度>高郁闭度;(4)不同森林类型林下灌木层单位面积生物量、碳密度随着乔木层林龄的增加总体呈先减少后增加趋势,生物量大小为幼龄林>成、过熟林>中龄林>近熟林。 相似文献
7.
文章利用RS和GIS的空间分析技术,以TM遥感影像为主要信息源,通过目视解译的方法提取研究区土地利用动态变化数据,结合现地调查进行区域土地利用动态变化分析。研究结果表明:研究区不同土地利用类型之间转换明显,其中,以耕地、草地面积减少,林地、灌木林地、居民地和工矿用地增加为主。土地利用类型变化主要受经济因素影响,国家投入增加和地方经济的发展是土地利用变换的主要原因。 相似文献
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普者黑省级自然保护区土地利用及景观格局变化研究 总被引：1，自引：0，他引：1
基于2006年和2016年丘北普者黑省级自然保护区的森林资源二类调查数据,综合运用数理统计和景观生态学理论和方法,对普者黑自然保护区2006-2016年土地利用和景观格局变化进行研究。结果表明,自然保护区各地类在10年间均向其他用地类型进行相互转化,按各地类变化面积排序为:农用地有林地灌木林地水域未成林地宜林地未利用地建设用地非林地苗圃地疏林地;按各地类面积增加排序为:有林地灌木林地建设用地疏林地无立木林地非林地水域未利用地未成林地宜林地农用地。研究区主要以农用地、有林地、灌木林地、水域和建设用地为优势景观;这几类景观斑块分布相对分散,切割程度和破碎化程度增加。在景观尺度方面,景观斑块总体呈现出多样化、破碎度、形态复杂化;不同类型景观的团聚程度、延展性和连通性减弱,分布离散性增强,呈现出非均衡性、异质性趋势变化的景观格局。 相似文献
10.
小陇山龙门林场森林资源动态变化分析 总被引：1，自引：0，他引：1
依据甘肃省小陇山林业实验局龙门林场1994和2008年二类调查(森林资源规划设计调查)数据,从森林资源各类土地面积、蓄积量、组成结构等方面分析了该林场14年间森林资源消长变化规律,并对变化的原因进行了分析。结果表明:龙门林场有林地、宜林地、未成林地、苗圃地等地类面积呈增加趋势;灌木林地、疏林地、无林地等地类面积呈减少趋势;从蓄积量来看,活立木蓄积量持续上升,生长量大于消耗量。人工林的面积增长较快,以落叶松林为主,未成林造林地则为针叶、阔叶和针阔混交;从林龄结构上来看,中龄林增长较快。 相似文献
11.
Breakdown and macroinvertebrate colonization of conifer needles (Cryptomeria japonica) and deciduous broadleaves (Euptelea polyandra) were investigated using litter bags in two study sites in streams flowing through a conifer plantation of C. japonica in Shikoku, southwestern Japan (one site with conifer canopy and another with mixed conifer and broadleaved canopy). Breakdown
rates and macroinvertebrate densities were compared between litter species (conifer needle vs broadleaf) and between the two
sites (conifer vs mixed canopy) to determine (1) whether breakdown rate of broadleaves is higher than conifer needles, (2)
whether macroinvertebrates prefer broadleaves to conifer needles, and (3) whether the difference in riparian canopy is reflected
in macroinvertebrate abundance. The results indicated that breakdown rates of broadleaves were higher than those of conifer
needles, suggesting poorer quality of the latter as food for macroinvertebrates. Differences in macroinvertebrate density
between needles and broadleaves were generally consistent with those in breakdown rates: broadleaves tended to have higher
densities than needles, suggesting that conifer needles were not preferred by macroinvertebrates. However, total macroinvertebrate
density in the conifer site was not significantly different from that in the mixed site, although the dominant shredder taxon
differed (conifer site: gammarids; mixed site: lepidostomatids). Although conifer needles are low-quality food for macroinvertebrates,
this may offer some advantages. Conifer needles remain on the streambed for longer periods owing to their lower breakdown
rates, being a constantly available resource. In addition, accumulations of conifer litter may effectively trap and retain
particulate organic matter. 相似文献
12.
基于BP神经网络的针阔混交林TM遥感图像自动分类技术研究 总被引：3，自引：0，他引：3
在对标准BP神经网络试验分析的基础上，通过输入矢量归一化处理、主成分分析、增加验证集、改进训练学习算法、扩大隐层和输出层规模等措施，对BP神经网络自动分类系统进行改进；利用改进后的BP系统对吉林省汪清林业局的典型针阔混交林TM遥感图像进行辩识、分类试验研究。结果表明：改进后的BP网络分类系统自动分类精度提高了19．14％，比传统无监督自动分类精度提高8．55％，达到了区分森林类型的分类要求。研究还显示了该改进系统应用于针阔混交林TM遥感图像自动分类识别的精度随网络规模增大而提高。 相似文献
13.
大兴安岭地区森林景观沿主要河流两侧分布的变化 总被引：1，自引：1，他引：1
In this paper, the regularity and changes of the forest landscape along the major rivers, namely, Nuomin River, Bila River and Zhawen River in Daxing‘ an Mountains, Bilahe Forestry Bureau based on the interpretation of TM data were studied. The results showed that the regularity has changed a lot due to the gradually stronger human intervention on forest landscape. The most obvious change was the cultivated lands had been expanding alongside the major rivers. With the increasing of population, the only way to satisfy the increasing needs of the local people for subsistence is by expanding cultivated lands because of the backwardness of agriculture productivity. The regularity of conifer distribution along rivers of 1997 has changed in the diverse direction of that of 1988. The proportion of conifer gradually increases with 1 000 m further away from the major rivers. That is due to the favorable availability of conifer alongside river bank, the most populated area in the forest region. 相似文献
14.
The effect of geographical variation of planting rate on the uptake of carbon by new forests of Great Britain 总被引：1，自引：0，他引：1
The planting rates from 1921 to 1996 of new coniferous and broadleavedforests for 11 regions of Great Britain were assembled for thestate and private sectors. Over that period new planting totalled231 kha of conifers and 132 kha of broadleaves in England, 141kha of conifers and 16 kha of broadleaves in Wales and 881 khaof conifers and 52 kha of broadleaves in Scotland. These time series and regional values of Yield Class were usedas input data for an accounting model of carbon in the trees,litter, soils and products to produce estimates of their netuptake of carbon by the forests from the atmosphere (i.e. increasein the carbon pools). On the assumption that conifer and broadleafplanting could be represented by Sitka spruce and beech treesrespectively, litter and forest soil in Great Britain were accumulatingcarbon at 2.42 Mt a–1 in 1995–96. Coniferous forestaccounted for 89 per cent of this uptake. Scottish conifer andbroadleaf forests took up 68 per cent and mapping the uptakeshowed that the greatest rate occurred in western Scotland.The pool of carbon in wood products increased in 1995–96by 0.31 Mt a–1. The estimated uptake rates were sensitive to the relative amountsof conifer and broadleaf forest planted (particularly in relationto increases in the pool of carbon in wood products) but notto regional differences in Yield Class. Use of any single YieldClass in the range 10–16 m3 ha–1 a–1 for allSitka spruce planting produced estimates of uptake rate in GreatBritain to trees, litter and soil within ±10 per centof that, assuming yield varied across the country. Lack of preciseknowledge on the parameters of the model was estimated to introducean uncertainty of ±30–70 per cent into estimatesof carbon uptake. 相似文献
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城市国家森林公园地处城市规划区内,林种为单一的风景林,承担着风景旅游、自然保护、市民休闲等多项职能,决定了城市国家森林公园经营方向的多样性、复杂性。本研究以南京紫金山国家森林公园为研究对象,以森林资源二类调查数据、高分辨率遥感图像QuickBird为主要信息源,结合森林美学评价成果,以ArcGis9.0为空间分析平台,从生态功能、森林美学2个方面将紫金山国家森林公园区划为山北森林游览区、自然保护区、山岳生态保护区、名胜古迹区、山南市民休闲区5个经营单位,从而有效地协调风景旅游、生态保护、市民休闲等多种需求之间的矛盾,为城市国家森林公园的经营区划提供借鉴。 相似文献
16.
本文对两期遥感图像进行解译，并在GIS支持下提取露水河林业局主要河流两岸各缓冲区森林资源信息，经分析得到各类地物在1985年及1999年的变化趋势。结果表明：在河流沿岸对森林的采伐强度1999年较1985年明显减小，整体生态环境较1985年有所改善。在缓冲区1，2，3除中龄针叶林大幅度增加外，其它地物类型面积均减少，由此可以看出，在这三个缓冲区内针叶林得到了较好的恢复。在缓冲区4内，中龄针叶林、成熟针叶林、成熟阔叶林形成一个林龄梯队，有利于森林生态系统的稳定与功能的发挥，十五年间缓冲区4受到的干扰相对较小。湿地数量在四个缓冲区内均有所减少，虽然在缓冲区4内森林生态系统恢复的较好，但湿地面积仍有所减少，说明保护及恢复湿地资源是一件非常艰巨的任务，必须引起高度重视。图5表2参12。 相似文献
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基于森林资源规划设计调查资料,利用ArcMap 10、Fragstats 4.1、DPS 14.1、Excel等软件,选取常用的景观指数,分析云南省腾冲县天然林的景观格局特征,结果表明:①腾冲县天然林景观总体异质性高、形状复杂、聚集程度高、斑块分布比较均衡,景观格局特征比较复杂;②各森林类型面积比例从大到小依次为栎类林其它阔叶林云南松林针阔混交林旱冬瓜林硬阔林竹林冷杉林软阔林华山松林铁杉林,栎类林、其它阔叶林面积占61.51%,是腾冲县天然林景观的主要组成部分,云南松林、针阔混交林、旱冬瓜林面积占32.04%,是腾冲县天然林景观的重要组成部分,硬阔林、竹林、冷杉林、软阔林、华山松林、铁杉林面积仅占6.45%,面积虽小,但在天然林景观中具有特殊的作用;③因子分析结果,从稳定、复杂、异质性高、破碎化低、抗干扰能力强等方面综合评价,按得分从高到低依次是栎类林其它阔叶林云南松林硬阔林针阔混交林旱冬瓜林竹林冷杉林铁杉林华山松林软阔林;④聚类分析结果,可把腾冲县天然林分为4类,第一类是破碎度低、形状复杂、异质性高、抗干扰能力强的栎类林和其它阔叶林,第二类是破碎度高但形状复杂、异质性高、抗干扰能力强的云南松林、针阔混交林和旱冬瓜林,第三类是斑块间平均距离远、聚合度高、呈群团状分布的硬阔林、竹林、铁杉林和冷杉林,第四类是破碎度高、形状简单、异质性低、抗干扰能力弱的华山松林和软阔林;⑤聚类分析结果在因子分析的基础上,体现了硬阔林平均几何最邻近距离远的特征,对腾冲县天然林景观格局的评价效果比因子分析更好。 相似文献
18.
In the Pacific Northwest, USA, red-tree voles (Arborimus longicaudus) are of conservation and management interest owing to their apparent association with late-seral forests and the relatively small extent of such forests, largely a function of timber harvest, fire, and conversion of forests to non-forest uses during the past century. We created and evaluated a series of red-tree vole habitat association models, and applied the best model to evaluate tree vole habitat quality within and outside of reserves throughout most of their range in Oregon and northern California. We modeled presence and absence of tree vole nests across a gradient of biotic, abiotic, and spatial features; and within and outside of reserves. The best model included spatial coordinates, percent slope, basal area of trees with diameter at breast height (dbh) between 45 and 90 cm, maximum tree dbh, and standard deviation of conifer dbh. Plots with tree vole nests contained many late-seral/old-growth forest attributes such as large diameter, older, and variably sized trees. Evaluation of the best model, including rigorous cross-validation, showed the model to be statistically robust and to have very good/excellent predictive ability. Reserves had significantly higher mean habitat quality than non-reserved lands, and reserves had much more high quality habitat than non-reserves. 相似文献
19.
James D.A. Millington Michael B. Walters Megan S. Matonis Jianguo Liu 《Forest Ecology and Management》2010
Understanding the impacts of local and regional landscape characteristics on spatial distributions of wildlife species is vital for achieving ecological and economic sustainability of forested landscapes. This understanding is important because wildlife species such as white-tailed deer (Odocoileus virginianus) have the potential to affect forest dynamics differently across space. Here, we quantify the effects of local and regional landscape characteristics on the spatial distribution of white-tailed deer, produce maps of estimated deer density using these quantified relationships, provide measures of uncertainty for these maps to aid interpretation, and show how this information can be used to guide co-management of deer and forests. Specifically, we use ordinary least squares and Bayesian regression methods to model the spatial distribution of white-tailed deer in northern hardwood stands during the winter in the managed hardwood-conifer forests of the central Upper Peninsula of Michigan, USA. Our results show that deer density is higher nearer lowland conifer stands and in areas where northern hardwood trees have small mean diameter-at-breast-height. Other factors related with deer density include mean northern hardwood basal area (negative relationship), proportion of lowland conifer forest cover (positive relationship), and mean daily snow depth (negative relationship). The modeling methods we present provide a means to identify locations in forest landscapes where wildlife and forest managers may most effectively co-ordinate their actions. 相似文献
20.
Forest resources variation along with the main rivers in typical forest region of Changbai Mountain 总被引：1，自引：0，他引：1
The restoration of the riparian vegetation disturbed by human activities is one of the hotspots of watershed ecology. Through
interpreting the images of Remote Sensing in 1985 and 1999, the basic information of forest resources of Lushuhe Forest Bureau,
which is a typical forest area of Chanbai Mountain was obtained with support of GIS. By dividing Land covers of Lushuihe area
into 10 types (water body, residential land, stump land, farming land, wetland, mature conifer forest, midlife conifer forest,
mature broadleaf forest, midlife broadleaf forest, and man-made young forest) and dividing the riparian zone into four buffers
(in turn 1000, 2000, 3000, 4000 m away from the river), the changes of riparian forest resources during 1985–1999 were analyzed.
The results showed that the deforestation intension has obviously decreased and the whole environment has been evidently improved,
but the riparian ecosystem was still flimsy. In buffer 1, 2, 3 the area of midlife conifer forest increased largely, but the
areas of other types of land covers all decreased. Midlife conifer forest had a comparatively good status in the three buffers.
In buffer 4, midlife conifer forest, mature conifer forest, and mature broadleaf forest formed a forest-age rank that is helpful
to stabilize the forest ecosystem and exert its functions. Area percentage of wetland decreased in buffer 1, buffer 2, and
buffer 3, even in buffer 4 in which forest ecosystem rehabilitated comparatively well, so protecting and rehabilitating wetland
is a very difficult task.
Foundation item: This study is supported by major projects of Knowiedge Innovation Program. Chinese Academy of Sciences (No. KZCX2-SW-320-3)
and Institute of Applied Ecology (a grant SCXZD010-01), CAS.
Biography: HAO Zhan-qing (1962-), Male, Ph. Doctor, Professor in Institute of Applied Ecology, Chinese Academy of Science, Shenyang
1100016, P.R. China
Responsible editor: Chai Ruihai 相似文献