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1.
海南岛不同海拔高度青皮林群落结构与多样性   总被引:2,自引:2,他引:0  
对海南岛不同海拔高度青皮为优势种的群落进行了典型抽样调查,共计调查临时样方13个,总面积2 800m2,分析了不同海拔高度对青皮林群落的物种组成、结构及群落特征的影响。分析结果表明:不同海拔高度青皮群落的优势种组成存在显著差异;青皮成树(DBH≥5cm)重要值和群落多样性与海拔高度呈相反变化趋势;不同海拔高度青皮成树株数各径级分布均呈倒J曲线分布,但差异较大,随海拔高度的升高,倒J曲线越趋于平缓;成树青皮株数、比例和断面积均随海拔高度的升高而减少,青皮平均胸径则随海拔高度的升高而增加。  相似文献   

2.
石梅湾青皮林群落结构及天然更新特征   总被引:2,自引:1,他引:1  
通过样方调查法对石梅湾青皮林群落结构及天然更新特征进行了调查分析,结果显示:过伐林和次生林的特征较明显,过伐林比次生林的青皮断面积和平均胸径分别高53.98%和19.43%,而次生林比过伐林的青皮密度高17.47%;两林分中均为青皮占绝对优势,青皮组成均为95%(断面积),且重要值均高于0.80;次生林和过伐林中青皮的径级结构主要分布在5~20cm径级,其中5~10cm径级株数最多,分别占总株数的74.57%和66.06%;2种林分幼树更新数量充足,但过伐林青皮幼苗更新不足,仅1 550株/hm2;更新幼苗、幼树均呈聚集分布,且聚集程度很高。  相似文献   

3.
尖峰岭热带山地雨林不同更新林的群落特征   总被引:4,自引:0,他引:4  
基于对尖峰岭热带山地雨林原始林、皆伐后恢复41 a的天然更新林和皆伐后恢复25 a的人工促进天然更新林的调查数据,对其物种组成、物种相似性、物种丰富度及多样性、植株密度和稳定性等进行比较分析,并通过优势种群龄级结构分析预测群落的发展趋势.结果表明:1)物种丰富度及物种多样性均以原始林最高,乔木层物种多样性表现为天然更新林>人工促进天然更新林,幼树层和下木层表现为人工促进天然更新林>天然更新林;2)天然更新林与原始林的物种相似性比其与人工促进天然更新林的高,说明天然更新林恢复程度较人工促进天然更新林好;3)植株密度表现为人工促进天然更新林>天然更新林>原始林,与干扰程度正相关,与皆伐后恢复时间负相关;4)乔木层和下木层的群落稳定性表现为原始林>天然更新林>人工促进天然更新林;5)优势种群发展趋势分析表明,原始林群落主要优势种群大部分表现为增长或稳定趋势,天然更新林群落上层阳性树种表现为衰退或稳定趋势,下木层的优势种则表现为增长趋势,人工促进更新林的栽培种和一些偏阳性树种表现出衰退或稳定趋势,林下一些优势度稍低的种群表现出逐渐增长趋势.因此,虽然天然更新林和人工促进天然更新林所在群落具有一定的稳定性,但其种类组成结构将发生较大的变化,仍处在由前期阳性树种向后期耐荫树种转变的演替进程中.  相似文献   

4.
川西南山地云南松林窗更新特征   总被引:4,自引:0,他引:4  
词查四川省攀枝花市原始云南松林中的65个林窗,研究林窗的面积、年龄和开阔度对云南松更新的影响.结果表明:林窗干扰有利于云南松天然更新;小林窗中云南松幼苗更新密度最大,大林窗中云南松幼树及成树的密度较大;幼苗和幼树在幼年林窗中密度较大,而成树在老年林窗中密度最大;云南松幼苗密度随开阔度的提高而降低,幼树和成树的密度则增加;开阔度越大云南松个体也越大,但在开阔度低于0.6的林窗中,云南松更新困难;林窗和非林窗下云南松的重要值均排第1位,表明未来该研究区仍以云南松为优势种.  相似文献   

5.
通过对全国5省(区)10个县(市)大叶栎(castanopsis fissa)生长调查,研究大叶栎结实习性、天然更新规律、生长及适应性、群落习性、病虫害发生规律、经营与利用特性等,结果表明大叶栎为优良乡土树种,具有较强的结实和天然更新能力,可人工植苗、直播造林、天然更新,最适“近自然”经营,适应性强、生长快、材质好,是优良薪炭、纤维板、造纸、高档家具、菇木及防火林带树种,也是优良生态公益林树种。  相似文献   

6.
朝阳地区油松人工林天然更新的主要类型   总被引:1,自引:0,他引:1  
采用标准地调查方法对朝阳地区油松人工林天然更新进行了研究,将其归纳为疏林林下更新、林缘更新、侵蚀沟更新、林隙更新和动物传播种子更新5种类型。不同坡向疏林地油松天然更新幼树株数差异明显;侵蚀沟内油松天然更新明显优于正常坡面;阴坡林隙更新良好,阳坡林隙基本不能进行天然更新;油松林缘更新幼树主要分布于距林缘20 m以内;动物传播种子天然更新多以散生天然油松幼树形式存在。  相似文献   

7.
开远市原生植被类型的垂直分布状况调查   总被引:1,自引:0,他引:1  
通过对开远市不同海拔高度原生植被类型状况的设样调查,得出开远市原生植被的垂直分布规律为:海拔高度1 500 m以下分布着以毛叶青冈为代表的偏干性季风常绿阔叶林、细叶云南松林;海拔高度1 500~2 000 m生长有元江栲、银木荷湿性常绿阔叶林、云南松林;而海拔高度2 000 m以上为红花荷、黄丹木姜子群落及光叶石栎群落组成的中山湿性常绿阔叶林。而在海拔高度1 100~1 200 m干热河谷地带分布的铁橡栎、清香木群落不作该地的代表类型。结合垂直分布规律,对除细叶云南松林外的6种植被类型的物种分层结构特征作了论述。  相似文献   

8.
通过对广东省深圳市羊台山森林公园林分状况的调查发现,该公园地带性植被为次生南亚热带常绿阔叶林和南亚热带沟谷雨林,组成种类以桃金娘科、樟科、五加科等热带、亚热带特征较强的科属为主,形成以红鳞蒲桃、鸭脚木、浙江润楠、芳槁润楠、樟树等为优势种的几种森林群落。由于林分主要是由受严重干扰的植物群落恢复形成的天然次生林,普遍质量差,生物多样性面临的问题比较突出。研究分析了羊台山森林公园的主要群落类型、群落主要乔木树种的重要值、优势科及组成比等,提出了地带性乡土树种、景观和环境友好树种选择的建议,对森林公园的次生林改造和森林保育具有参考作用。  相似文献   

9.
利用金沟岭林场8块落叶松人工林固定标准地1986年、2001年、2008年的更新调查数据,研究了其天然更新的密度和分布格局动态。结果表明:林龄为中龄林(1986年)、近熟林(2001年)、成熟林(2008年)时,天然更新密度分别为1 734、1 956、2 544株/hm~2,中龄林、近熟林天然更新等级均为不良,成熟林更新等级为中等;中龄林更新较多的为云冷杉等针叶树种,随着林龄的递增,阔叶树种的更新增多;全林分在中、近、成熟林阶段分布格局均为聚集分布,聚集的程度随着林龄的增加而降低;各个树种更新分布格局也随林龄变动而发生变化,成熟林时,分布格局均为聚集分布。本研究通过分析更新密度和幼苗幼树的格局分布随林龄的动态变化,揭示落叶松人工林天然更新的发展趋势为云冷杉针阔混交林,为林分的可持续经营提供理论依据。  相似文献   

10.
章古台沙地赤松天然更新的初步研究   总被引:3,自引:3,他引:0  
通过2年的野外调查与比较分析,认为在章古台沙地赤松天然更新是可行的。天然更新方式有3种,即林下更新、林隙更新和林缘更新。天然更新幼树在空间上呈带状、群团状分布;更新幼树年龄在时间上是连续的,降水量大的2004、2005、2008年更新幼树相对较多;更新幼树密度为20 300~100 000株.hm-2。赤松林缘天然更新幼树长势要好于林隙,林隙要好于林下。所以,要充分利用各种条件,进行天然更新和人工促进天然更新。  相似文献   

11.
尖峰岭国家级自然保护区青皮林资源及其垂直分布特征   总被引:9,自引:0,他引:9  
方洪  李意德  罗文  蒋忠亮  陈焕强 《热带林业》2004,32(4):43-46,38
尖峰岭国家级自然保护区三分区的青皮林是目前海南岛保存最好的林分之一,其生态系统的原生性较强.组成种类繁多,林分结构合理,平均胸径为28.6cm,最大植株胸径达143.3cm,23个样方中有14个样方出现了胸径≥70cm的大乔木;林木蓄积量高达469.773m^3/hm^2,而青皮、细子龙、野生荔枝、盘壳栎等13个种的蓄积量占总蓄积量的45%,其余301个少见种或偶见种的蓄积量只占55%,反映了青皮是热带常绿季雨林生态系统关键种的现实。青皮与细子龙、野生荔枝等的最佳分布海拔在300m~650m之间,它们与向低海拔分布的白茶、翻白叶和向高海拔分布的大叶白颜、青兰、拟核果茶等一道组成了热带常绿季雨林的表征种类。  相似文献   

12.
海南中部山区什运乡小斑块分布次生林的数量分类   总被引:1,自引:0,他引:1  
应用DCA排序和TWINSPAN分类方法,将海南中部山区什运乡区域内分布的小斑块次生林划分为7个群落类型:毛叶青冈+香合欢+毛柿群系(Form.Cyclobalanopsis kerrii+Albiza odoratissima+Diospyros strigosa)、枫香+岭南山竹子+黄椿木姜群系(Form.Liquidambar formosana+Garcinia oblongifolia+Litsea variabilis)、黄牛木+九节+青梅群系(Form.Cratoxylumcochinchinense+Psychotria rubra+Vatica mangachapoi)、鸭脚木+木荷+短穗探柯群系(Form.Schefflera octophylla+Schimasaperba+Lithocarpus fenestratus)、长圆叶新木姜+南岛青冈群系(Form.Neolitsea oblongifolia+Cyclobalanopsis insularis)、黧蒴栲单优群系(Form.Castanopsis fissa)、黄叶树+皂帽花+美叶菜豆树群系(Form.Xanthophyllum hainanense+Dasymaschalontrichophorum+Radermachera frondosa)。DCA排序第1轴反映了群系自南向北的空间分布情况和温度变化梯度,第2轴上呈现的环境意义不明显。  相似文献   

13.
To aid in management of Cunninghamia lanceolata,the main timber species in Southern China,its variation of spatial distribution pattern was analyzed.Three permanent plots of C.lanceolata plantations with approximately the same site conditions,set by China continuous forest inventory in Shunchang,Fujian,were selected. C.lanceolata growth was divided into two stages: young trees(5 cm≤diameter at breast height (DBH)<10 cm) and mature trees(DBH≥10 cm). The DBH and coordinates of every tree(DBH≥5 cm) in the permanent plots were recorded in 2003 and 2008.The function L(r),improvement of Ripley’s K(r),the paircorrelation function g(r),and the uniform angle index(W_i) were used to analyze the spatio-temporal variation of spatial distribution patterns.The three permanent plots had mean uniform angle index(W) between 0.494-0.578 at low altitudes,0.465-0.477 at medium altitudes,and 0.426-0.601 at high altitudes.Results showed that altitude did not affect the spatial distribution pattern. The L(r ) and g(r) function curves of mature trees were generally lower than young trees’,i.e.tend to be more random or uniform distribution.So regardless of the initial distribution of young or mature trees,with the passage of time,there was a tendency for the aggregated distribution to change to a random distribution,and a random distribution to change to a uniform distribution.  相似文献   

14.
海南霸王岭林区青皮天然林资源与乔木层群落学特征   总被引:1,自引:0,他引:1  
以海南霸王岭自然保护区3 600m2青皮林样地的调查材料为基础,分析了青皮林群落资源与乔木层群落特征。结果表明:林分平均蓄积量149.49m3/hm2,最高达330.98m3/hm2;平均胸径10.2cm,最大胸径44.0cm;平均树高9.6m。青皮由于相对密度、相对优势度较大,重要值达161.415 9,导致其他物种种类减少,造成群落生物多样性降低。  相似文献   

15.
福建万木林自然保护区古树名木资源初步研究   总被引:10,自引:1,他引:10  
对建瓯万木林自然保护区森林群落的古树名木资源调查结果表明 ,胸径≥ 80cm的古树名木有 5 6 9株 ,隶属于 15科2 1属 2 9种。笔者对万木林自然保护区古树名木的种类、种群数量、生态分布、树高和胸径等现状进行分析 ,提出了保护该区古树名木的对策  相似文献   

16.
Variation in floristic composition of recovering BaikiaeaGuibourtiaPterocarpus woodlands was studied in different development stages (from early regrowth to mature woodland) under different land-use systems (protected areas, timber harvesting, pole and firewood collection, and abandoned crop fields), in the Gwayi and Tsholotsho areas in north-western Zimbabwe. A total of 150 nested circular plots were sampled representatively in four different development stages related to the land-use systems. The DBH (stem diameter at 1.3 m above ground level) and tree height were recorded by species for all stems of tree species with DBH ≥ 15 cm in a 30-m-radius plot (0.283 ha) and for trees with DBH 5.0–14.9 cm in a 11.3-m-radius plot (0.04 ha) (both centred around the same midpoint). Stems with DBH < 5 cm were counted by species in an inner sub-plot of 5.65 m (0.01 ha) radius. Tree data (stem DBH ≥ 5 cm) and regeneration data (stem DBH < 5 cm) by stem counts per species per plot, were used separately to run TWINSPAN (TWo-way INdicator SPecies ANalysis) classifications of species assemblages. Importance values were calculated for all tree species per community. Shannon–Wiener diversity indices were calculated for each community and tested for differences using one-way ANOVA in SPSS version 21. Detrended correspondence analysis (DCA) implemented in the CANOCO ordination software was used to determine the extent of variation amongst the identified communities. The classification identified 12 tree communities and 13 regeneration communities, clustering plots from different land uses together. Baikiaea plurijuga was the most important tree species in all tree communities, except where Combretum collinum, C. apiculatum, Commiphora mossambicensis and Pterocarpus angolensis were dominant. Pterocarpus angolensis showed low importance in most communities, except for communities from undisturbed sites (mostly mature trees) and abandoned fields (mostly young trees). Baikiaea plurijuga was most important in most regeneration communities, except in communities dominated by Baphia massaiensis, C. collinum, C. apiculatum and P. angolensis. Species diversity differed significantly (p < 0.05) amongst tree communities. The DCA ordination showed little variation amongst the communities. The cumulative contribution of environmental factors explaining variation in species composition was 22.6% for tree communities and 26.1% for regeneration communities, suggesting that recovery from disturbance after different land uses may explain more of such variation.  相似文献   

17.
文章从自然植被、地方文化和传统建筑特点等方面对建设海南热带特色园林进行初步探讨,并有针对性地推荐青梅(Vatica mangachapoi)等63种优良园林植物用于构建海南热带园林景观。  相似文献   

18.
To date only one species of the genus Vatica Linn.(Dipterocarpaceae) has been identified, and a subspecies and three varieties have been reported on Hainan Island, China. However, it remained controversial whether the species was Vatica mangachapoi or a new species Vatica hainanensis, and whether the subspecies or varieties are taxonomically valid. We evaluated here morphometric variations of 133 trees collected from nine populations and herbarium specimens of Vatica spp. using 16 traits of leaf and fruit. Among these, leaf traits varied more within and among populations than did fruit traits. Four traits of ratios were more stable than directly-measured traits within and among populations. The ranges of lamina length, lamina width and height of maximum lamina width point were the greatest among the 16 traits, while number of lateral veins varied least among the 12 directly-measured traits. Measurements from all 9 populations overlapped for each morphological trait, and variation of each trait was continuous among both individuals and populations. The range of variation did not distinguish any specimen from V mangachapoi as described in the flora of Southeast Asia By cluster analysis, individuals of each population as wel as specimens of each variety formed no distinct clusters The published varieties thus were characterized by no distinguishing variations in comparison with the nine sampled populations. In conclusion, the new species V hainanensis as well as the subspecies and varieties were not supported by our comparisons, and only V. man gachapoi without any subspecies or varieties occurs on Hainan Island, China.  相似文献   

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