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云南省绿化委员会办公室根据《全国绿化委员会办公室关于开展古树名木保护情况调研考察的通知》要求,对全省的古树名木进行了认真全面的调查研究。一、云南省古树名木资源数量、种类及分布现状(一)古树名木现有总量云南省现有古树名木总数1709379株, 相似文献
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文成县古树名木调查与研究 总被引：1，自引：1，他引：1
采用全球卫星定位仪(GPS)实地定位,逐株、逐片每木调查的方法,对文成县的古树名木资源进行了全面系统的调查,并就古树名木树种与数量、生长状况、分布情况和树龄与保护级别等进行了分析研究,建立了资源数据库,结果表明,文成县现存古树名木2 665株,隶属25科42属54种,其中一级古树名木122株,二级古树名木548株,三级古树名木1 955株,并后提出了保护管理措施与建议. 相似文献
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河源市古树资源特征分析研究 总被引：1，自引：0，他引：1
为了加强对古树的科学保护与管理，通过访谈估测法、文献追踪法、树龄与胸径回归模型估测法等方法，对河源市的古树进行研究。结果表明：1）古树数量共计 1995 株，集中在红锥 Castanopsis hystrix、榕树 Ficus microcarpa、枫香 Liquidambar formosana、木荷 Schima superba、雅榕 Ficus concinna等观赏树种以及龙眼等经济树种；2）古树树龄相对集中，主要属于三级古树，平均年龄为 195.56 a； 3）古树分布特征差异明显，主要集中在丘陵与山区县域，尤以客家乡村最为密集；4）古树健康状况总体较好，受虫害及建设扰动使部分古树出现衰弱与濒死情况；5）古树生长状况较佳（P<0.01）。研究指出，古树保护即将进入一个科技与文化并重的时代，需要做到依照古树类型、古树年龄、文化区域、健康状况、生长系数等多要素兼顾的精细化管理。 相似文献
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《山西林业科技》2016,(3)
古树名木是重要的森林资源和旅游资源。笔者对广州市花都区古树名木资源与区系特征进行调查分析,结果显示:花都区已挂牌保护的古树名木现存554株(含格木古树群1个),其中,三级古树553株、名木1株;资源量较为丰富,隶属17科20属23种,以被子植物为主,格木(Erythrophleum fordii Oliv.)、细叶榕(Ficus microcarpa L.f.)分别有273株、221株,共占全区古树名木总量的89.17%.全区古树名木科、属的热带分布型占优势地位,分别占总科数的82.35%和总属数的90.00%;部分植物在科分类上具有较古老的成分。花都区古树名木的立地场所可划分为4种类型:村落、机关企业庭院、景区、道路。其中,以村落分布数量最多(占92.24%)。此次调查可为花都区古树名木的保护、养护复壮及开发利用提供技术支持。 相似文献
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海口市古树名木现状及其保护对策 总被引：4，自引：0，他引：4
根据海口市(2005~2006年)古树名木普查结果,讨论分析了海口市古树名木的数量、种类、树龄组成及分布情况,结合保护现状及存在问题提出了相应的保护对策。
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玉屏侗族自治县古树名木资源特征分析及保护对策 总被引：1，自引：0，他引：1
采用实地调研、文献查阅、走访等方法,对玉屏侗族自治县境内古树名木的种类、数量、树龄,以及保护级别、生长势及植物区系特征进行调查,结果显示:玉屏侗族自治县共有古树名木485株,分属23科30属34种,其中,一级古树32株,二级古树38株,三级古树415株;古树名木的数量与海拔和坡度呈极显著相关,不同树种海拔、坡度分布差异较大;古树具有南北区系过渡特征,属的分布具有以温带分布为主,热带分布为辅的特点。通过调查发现,玉屏侗族自治县古树名木保护中存在缺乏保护资金,养护水平低,重保护轻利用等问题。针对相关问题,提出拓宽融资渠道,建设专业技术队伍,新建古树公园等保护和管理对策。 相似文献
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系统分析湖北省谷城县古树树种组成、分布特征以及影响古树生长的环境因子,并应用访谈法、文献追踪法、实地勘测法和类比推断法对谷城县古树进行调查,对古树的物种组成、分布以及生长状况,以及基于DEM坐标网格法对古树空间分布进行分析。结果表明,全县调查到存活古树共1 275株,隶属于26科41属51种。其中一级、二级和三级古树分别为99株、102株和1 074株;正常生长古树1 247株,衰弱古树26株,濒危古树2株。基于DEM经纬度（0.05°）和投影（5 km×5 km）网格数据分析,古树均呈聚集分布;古树在中、低海拔分布集中;海拔与古树生长势间呈显著正相关;环境因子和植物病虫害是影响谷城县古树生长的关键因子。谷城县古树空间和海拔高聚集度区域的人类活动最为频繁,建议地方林业部门根据现有古树资源分布特点及生物危害现状,科学制定古树保护规划和管护措施。 相似文献
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为加强古树名木资源的保护管理,采用GPS定位、文献跟踪、资料收集、现地鉴定、数码拍照等方法,2010-2018年在青海省互助县开展古树名木资源调查和评价。结果表明:(1)2010-2018年增或减古树名木数量没有变化,共有55株古树,全部为三级保护古树。以青杨、青海云杉居多,占总株数的90.91%。(2)古树名木全部以散生状态分布在乡村,4株为国家所有、48株为集体所有、3株为个人所有。(3)古树名木生长环境全部为中等,生长正常的有40株、衰弱的有15株。(4)古树名木树龄分布范围在108~288a,平均154a;树高分布范围在9~36m,平均20m;胸围/地围分布范围在150~740cm,平均364cm;冠幅分布范围在5~25m,平均16m。(5)2018比2010年树高增加了2m、胸围/地围增加了2cm、平均冠幅增加了2m。最后提出了古树名木资源保护管理的有关建议。 相似文献
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2011年8月通过访谈、查阅文献资料与实地调查,对贵州省古银杏资源的分布及生长特征进行分析。结果表明,贵州省100～4000年生古银杏共有1969株,主要分布于遵义市和六盘水市;垂直分布海拔为300～1700m,集中分布800—1100m。其中75．96％为雌株,24．04％为雄株,雌雄比为3．16：1;树高最高为50．0m,最矮为2．0m;树龄最大为4000年,最小为100年;胸径最大为479cm,最小为26cm;其平均冠幅最大为40．0m,最小为1．0m。垂乳银杏有88株,复干银杏有35株,雌雄同株仅1株。 相似文献
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A model (ROTATE) of the nitrogen (N) cycle during the tree and crop phases of fallow systems [Robertson, 1994] was used to determine the primary factors influencing longterm crop yields. The model simulated the expected patterns of increase in old (recalcitrant) soil organic N during tree rotations and their decrease under continuous cropping. After 3–4 fallow cycles an equilibrium soil organic N content is reached, where N losses by crop removal are balanced by N gains by the trees (either by fixation or pumping from depth) plus small inputs in rain. The rotation period has two variable components; the cycle length (tree plus crop period) and the fraction of years in each cycle occupied by trees (1 = sole trees, 0 = sole crops). Both components have optima determined by the time taken for the trees to increase the old soil organic N pool to an optimal (but not maximal) size. This optimum exists because the rate of increase in old organic N slows as the tree fallow progresses and a time is reached (often soon after the trees reach full size) when the benefits of further improvements in soil fertility are outweighed by crop yield foregone. In the example chosen of Acacia/sorghum in the Sahel, the optimum cycle seemed to be about 50 years with half of the time in trees. The optimum fallow period is shortened by growing fast-growing trees, and the benefit of fallow periods are greatest when (i) a large proportion of the N in litter (above and belowground) is transferred to the recalcitrant soil pool, and (ii) the trees attain a large size with correspondingly large annual additions of N to the soil. 相似文献
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One hundred and fifty-four jarrah (Eucalyptus marginata) and 85 marri (Corymbia calophylla) trees were measured and assessed, and the numbers and sizes of hollows in these trees were determined by destructive sampling; 665 hollows were located and measured. The relationship between tree diameter and tree age was determined from counts of annual growth rings on 162 of these trees. Large trees and trees with moderately senescent crowns individually bear the most hollows. Although the number of hollows found in individual trees increased with tree diameter, the distribution of tree diameters in the forest is skewed and the large number of small trees with diameters between 40 and 80 cm contribute approximately 50% of all hollows in the jarrah forest. The distributions of entry size, and of hollow depth, are highly skewed, with small hollows occurring more frequently than large hollows. Although jarrah trees bear more hollows than marri trees and the distribution of entry sizes is similar for both tree species, the hollows in jarrah are significantly smaller than the hollows in marri. Most hollows are cylindrical in shape, vertically oriented and occur in dead wood in the tree crown. Relatively few hollows (14%) occur in the tree bole or at crown break. Counts of hollows made from ground level are inaccurate as estimates of the actual number of hollows in trees. 相似文献
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Many invertebrates, birds and mammals are dependent on hollow trees. For landscape planning that aims at persistence of species inhabiting hollow trees it is crucial to understand the development of such trees. In this study we constructed an individual-based simulation model to predict diameter distribution and formation of hollows in oak tree populations. Based on tree ring data from individual trees, we estimated the ages when hollow formation commences for pedunculate oak (Quercus robur) in southeast Sweden. At ages of about 200–300 years, 50% of the trees had hollows. Among trees <100 years old, less than 1% had hollows, while all >400-year-old trees had hollows. Hollows formed at earlier ages in fast-growing trees than in slow-growing trees, which may be because hollows are formed when big branches shed, and branches are thicker on fast-growing trees in comparison to slow-growing trees of the same age. The simulation model was evaluated by predicting the frequency of presence of hollows in relation to tree size in seven oak stands in the study area. The evaluation suggested that future studies should focus on tree mortality at different conditions. Tree ring methods on individual trees are useful in studies on development of hollow trees as they allow analysis of the variability in time for hollow formation among trees. 相似文献
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Presence of different types of trees dispersed singly or in small groups throughout the fields is a very common feature in
the extensive rice paddies of Laos and Thailand. Factors such as land-settlement history, proximity to forest, and role of
species in the local culture are known to influence the nature and distribution of tree species so retained. The extent of
influence of these factors on tree-species composition and distribution in rice paddies was investigated in three villages
in Central Laos: Dongmakngeo, a newly established village with an abundance of adjacent forest; Bak, an old village with adjacent
forest; and Nakhou, an old village without any adjacent forest. At Dongmakngeo village, 23 species, mostly remnants from the
original forest, were observed in paddy fields. At Bak village, few trees were found in the paddy fields because villagers
had ample access to resources in the surrounding large forest. On the other hand, 119 species, 27 of which were planted, were
recorded at the forest-deprived Nakhou village; the scarcity of forest resources at Nakhou was compensated for by the utilization
and management of trees located among the fields, resulting in tree species changing from remnant to ruderal over time. Thus,
our results demonstrate that the pattern of tree distribution and species composition in paddy landscapes is not uniform,
but varies in relation to settlement history, topography, and human management. This has important implications for setting
both landscape-level land-use management plans and local tree management policies for achieving sustainable tropical paddy-dominated
agro-silvicultural systems. 相似文献
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2011年10月,通过资料收集和实地调查,对四川省古银杏资源的分布和结构特征进行分析。结果表明,四川省100～3000年生古银杏有974株,分布较集中,主要位于其中部的德阳、成都和雅安市。古银杏垂直分布海拔为400～3123 m,集中分布海拔为400～1200 m。在能确定性别的130株古银杏中,雌株占73.85％,雄株占26.15％。树高最高为50.0 m,最矮为2.0 m;树龄最大为3000年,最小为100年;胸径最大为4.80 m,最小为0.10 m;平均冠幅最大为29.0 m,最小为2.0 m。垂乳银杏有45株;复干银杏有55株;叶籽银杏仅1株。古银杏群共计15个,平均树龄在200～1100年,面积在500～8000 m^2。 相似文献