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双语推荐：乔木

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在2009年7—8月份和9—11月份,利用样线法和直接观察法对贺兰山牦牛(Bos grunniens)的生境选择进行了研究。结果表明:在7—8月份,牦牛偏好选择的生境——海拔3 000 m;植被类型为亚高山灌丛和草甸;乔木密度100株/hm2,乔木高度3 m,牦牛距离乔木的距离3 m;灌木种类以混合性灌木为主,灌木密度2 000丛/hm2,牦牛距灌木的距离1 m;上坡位;距水源距离800 m或800~1 200 m之间;距人为干扰距离4 000m;隐蔽级70%。在9—11月份,牦牛偏好选择的生境——海拔2 000~3 000 m;植被类型以山地针叶林为主;优势乔木以灰榆为主,乔木密度100株/hm2,乔木高度3 m;灌木密度2000丛/hm2,牦牛距离灌木的距离2 m;植被盖度50%~70%;下坡位;距水源距离1 200 m;隐蔽级70%。主成分分析表明:7—8月份,第一主成分的贡献率达15.679%,其中绝对值较大的相关系数是海拔高度、隐蔽级和乔木密度;9—11月份,第一主成分的贡献率达20.430%,其中绝对值较大的相关系数是牦牛距离乔木的距离、优势乔木、乔木高度和乔木密度。
From July to August 2009 and from September to November 2009 , we studied the habitat selections of feral yak ( Bos grunnieus) during summer and autumn in Helan Mountains.From July to August, yak preferred in higher attitude (>3 000 m) , in subalpine shrubland and meadow with lower tree density ( 3 m), shrub types mixture, higher shrub density (>2 000 individual/hm2), shorter distance to shrub ( 4 000 m) and higher hiding cover (>70%) .From September to November , feral yak used habitat in moderate attitude (2 000-3 000 m) , motane conifer forest, dominated by Ulmus glaucescens, tree density lower ( 2 m) , higher vegetation coverage (50%-70%), lower degree position, far from water resource (>1 200 m) and higher hiding cover (>70%).By principal components analysis, from July to August, the first principal component accounted for 15.679%. The higher correlation coefficients are attitude, hiding cover and tree density.From September to November, the first prin-cipal component accounted fo

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利用旌德县第8次森林资源二类调查数据，采取建立数学模型的方法分析了该县的乔木林总量及其年龄结构，依据建立的不同森林类型生物量和蓄积量之间的回归方程，估算了全县乔木林的碳储量及碳密度。结果表明：（1）旌德县乔木林总面积50190.7 hm2，乔木林总蓄积3624337 m3，以庙首镇森林面积最大。（2）乔木树种以杉类、硬阔和松类的面积和蓄积最大，乔木林的年龄结构较为合理；（3）乔木林生物量为118.18万t，乔木林碳储量为591485.20 t，碳密度为11.78 t/hm2，不同森林类型碳密度差异很大，以柏类的碳密度最大，达到27.63 t/hm2，软阔、硬阔林的碳密度较小，仅为0.73 t/hm2.和0.17 t/hm2.。因此，在实施各重点造林工程的同时加强中幼林抚育管理，提升现有林质量，促进林木生长，有效增加单位面积蓄积量，将会使旌德县森林的碳汇能力进一步提高。
In this paper the gross and age structure of arbor forests in Jingde County were analyzed using the data of the 8th Class II Forest Resources Survey in Jingde County and the established mathematical model, and the carbon storage and carbon density of arbor forests in the whole county were estimated with the established regression equation between the biomass and volume of different forest types. The results are as follows: 1. The total area of arbor forests in Jingde County was 50 190.7 hm2 and the total volume of arbor forests was 3 624 337 m3 with Miaoshou Township having the largest forest area;2. Tree species in Taxodiaceaeand Pinaceae and hardwood broadleaved trees had the largest forest area and largest volume, and the forest age structure was appropriate;3. The biomass of arbor forests was 1 181 800 t with the carbon storage totaling 591 485.20 t and the carbon density being 11.78t/hm2,and the carbon density of different forest types varied widely with that of Cupressa

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本研究在毕节关门山流域,选取乔木林地、灌木林地、荒地、果园及玉米地五种不同土地利用类型,研究了不同土地利用类型对土壤含水量和容重的影响,结果表明:1)在乔木林地和灌木林地表层土壤含水量随坡长增加变化不大,且乔木林地高于灌木林地;2)乔木林地和灌木林地坡脚土壤含水量高于坡中,坡中高于坡顶;3)五种土地利用条件下0-80cm深度内土壤含水量均随深度增加而递增;4)表土容重的变化次序为:乔木林地灌木林地果园地荒地玉米地。
The paper studied the effect of different types of land use on soil moisture and bulk density, via choosing arbor land, shrub land, abandoned land, orchard and corn field at Guanmenshan valley in Bijie. Re-sults showed that:1) soil moisture contents of arbor land and shrub land changed slightly with increasing slope length in the surface soil, but soil moisture contents of arbor land were higher than shrub land. 2) soil moisture contents of slope toe were higher than slope middle in arbor land and shrub land, and slope middle higher than slope top.3) soil moisture contents increased with depth in 0-80 cm soil depth under five land-use types. 4) The densities of super soil layer were arranged in the following sequence: arbor land>shrub land>orchard >abandoned land>corn field.

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利用混交度、角尺度、大小比数和开阔比数4个空间结构参数,结合空间结构单元距离尺度,研究了冀北山地杨桦次生林更新层和乔木层（低林层、中林层和上林层）的空间结构特征。结果表明：乔木层和更新层平均混交度分别为0.520、0.228,差异较大,乔木层混交度随林层增加而降低;乔木层和更新层的平均角尺度分别为0.575、0.530,属于聚集分布,乔木层聚集强度随林层增加而降低;乔木层和更新层平均大小比数分别为0.493、0.511,各等级林木分布较均匀;乔木层平均开阔比数为0.713,处于开阔的光环境中;随着林层增加,大小比数呈下降趋势,开阔比数呈增加的趋势,大小比数与开阔比数呈极显著负相关;参照木与4株最近相邻木的平均距离随林层增加呈递增趋势,但大部分相邻木分布在3 m以内。
We used four spatial structure parameters ( mingling degree, uniform angle index, neighborhood comparison and open comparison) and distance of spatial structure unit to study the spatial structure characteristics of regeneration layer and tree layer (lower, intermediate and upper layers) in secondary poplar-birth forest in the mountainous regions of northern Hebei. The average mingling degrees of tree layer and regeneration layer were 0.520 and 0.228, respectively, there was obvious difference in the average mingling degree, and the mingling degree of tree layer decreased gradually with increasing storey. The average uniform angle index of tree layer and regeneration layer were 0.575 and 0.530, respectively, which were within the aggregative distribution, and the aggregation degree of tree layer decreased gradually with increasing storey.The aver-age neighborhood comparison of tree layer and regeneration layer were 0.493 and 0.511, respectively, and the distribution of differ

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云杉属(Picea)和圆柏属(Sabina)乔木是青海省分布最广、蓄积量最大的乔木,弄清这2个属内各乔木树种含碳率的变化及其影响因素,对于青海省碳储量评估具有至关重要作用。考虑最小样本需求、样本的区域代表性和工作量等方面的因素,在青海省乔木林中云杉属和圆柏属乔木分布区内选取天然起源的云杉属乔木(包括:青海云杉Picea crassifolia、川西云杉P.likiangensis var.rubescens和紫果云杉P.purpurea)29棵和圆柏属乔木30棵(包括:祁连圆柏Sabina przewalskii和大果圆柏S.tibetica)作为青海省云杉属和圆柏属含碳率分析样本,采用干烧法对其树干、树皮、枝条、死枝、叶和根的含碳率进行测定。结果显示:(1)青海省云杉属和圆柏属5个乔木树种全株的含碳率在0.454 5(紫果云杉)至0.465 0(祁连圆柏)之间,其中云杉属的平均含碳率为0.460 6,圆柏属的为0.466 1,云杉属的含碳率显著低于圆柏属。(2)青海省云杉属和圆柏属5个乔木树种各器官含碳率在0.443 4(祁连圆柏的枝条)至0.496 4(大果圆柏的叶)之间;总体上叶的含碳率高于其它器官;同一树种不同器官以及不同树种同一器官的含碳率之间均存在差异,但是变化较小(变异系数均在4%以内)。(3)树种含碳率是树种本身属性(内因)和环境因素(外因)共
Picea and Sabina trees are the most widely distributed trees with the largest volume in Qinghai province. Understanding the changes and impact factor of carbon content rate of tree species in these 2 genera are important for carbon storage estimation in Qinghai province. Considering the minimum sample requirements, typical of sampling in the study area and workload, 29 Picea trees (Picea crassifolia, P. likiangensis var. rubescens and P. purpurea) and 30 Sabina trees(Sabina przewalskii and S. tibetica) were selected in natural forest of Picea and Sabina trees distribution area in Qinghai province. Carbon content rate of trunks, barks, branches, dead branches, leaves and roots in these samples was measured with dry combustion method. The results showed as below. (1) Carbon content rate of 5 tree species in Picea and Sabina was from 0.454 5 (P. purpurea) to 0.465 0 (S. przewalskii). Carbon content rate of Picea and Sabina were 0.460 6 and 0.466 1, respectively; the former was h

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蔷薇科植物多数经济价值高，在园林绿化中广泛应用。通过查阅文献和实地调查发现，广州城市城区公园常用的蔷薇科植物种类繁多，以小乔木、灌木为主，缺少高大乔木及地被植物，如果适当搭配常绿乔木、多花灌木和地被植物，可形成层次丰富的景观。此外，还要考虑观赏效果好、生态适应性强等综合价值较高的植物种类。
Most of the Rosaceae plant had high economic values and they were widely used in landscaping. Through literature research and field survey,it was found that Rosaceae plant species commonly used in Guangzhou City were various,mainly to small trees,shrubs,lack of tall trees and ground cover plants.Such as the configuration appropriate mix of evergreen trees ,floribunda shrubs and ground cover plants ,could form a hierarchical rich landscape. In addition ,the plants of higher comprehensive value should be considered ,such as good ornamental effect ,the ecological adaptability and so on.

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采用经典样方法对湖南芷江县南方红豆杉天然群落的种类组成、结构特征、物种多样性及植物区系等进行分析。结果表明：在1 000 m2样地中共有维管植物46科70属79种,其中蕨类植物5科7属8种,裸子植物2科2属2种,被子植物29科39属69种;群落分层明显,可划分为乔木层、灌木层和草本层;乔木层中有乔木树种17种,其中南方红豆杉和毛竹的重要值分别为81.51和43.37,远远超过其他的15种乔木树种,南方红豆杉的优势种群的作用明显,是群落的基调树种,毛竹为主要伴生种;灌木层包括乔木的幼树和灌木类,共40种;草本层植物有24种。物种多样性指数由高到低的顺序为灌木层〉草本层〉乔木层。植物区系地理成分复杂,科属组成均以热带性成分为主,温带成分占有较大的比例,反映出该群落植物区系由亚热带向暖温带过渡。
The species composition,structural characteristics,species diversity and plant flora of Taxus chinensis var. mairei natural communities in Hunan Zhijiang were analyzed using classical methods.The results showed that,there were 79 species of vascular plants in 1 000 m2 sample plot,belonging to 46 families and 70 genera,in which the bryophytes accounted for 5 families,7 genera and 8 species,the gymnosperms for 2 families,2 genera and 2 species,and the angiosperms for 29 families,39 genera and 69 species. The structure clearly divided into tree layer,shrub layer and herb layer,there were 17 kinds of arbor in the tree layer,and the impor-tant values of Taxus chinensis var.mairei and Phyllostachys pubescens were 81.51 and 43.37 respectively,which were far more than other 15 kinds of arbor.The advantages of Taxus chinensis var.mairei populations was obvious,and it was the keynote of species com-munities,Phyllostachys pubescens as the main companion species.Shrub layer included trees saplings

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采用丰富度（R1、R2）、多样性（D、H）和均匀度（J1、J2）各2种指数研究龙王山落叶阔叶林的物种多样性。结果表明，龙王山落叶阔叶林植物资源丰富，灌木种数最多，草本植物最少，共计有维管束植物54科91属140种（含变种）；群落层次分明，从上到下，分为乔木层、灌木层和草本层，并有少量层间植物。乔木层和草本层中优势种比较明显，灌木层中各优势种的差异不明显；丰富度指数（R1、R2），多样性指数（D、H），均匀度指数（J1、J2）的变化趋势均一致，灌木层＞乔木层＞草本层；t检验结果表明，各个层次之间的物种丰富度和多样性差异性均显著，灌木层的均匀度指数（J1、J2）与乔木层和草本层的差异性并不显著，而乔木层与草本层均匀度差异却相对显著。
Species diversity of plant communities in Longwang Mountain was studied by using seperately 2 in-dex of richness index (R1 ,R2 ),diversity indices (D,H)and evenness index(J1 ,J2 ).The results showed that the deciduous broad-leaved forest in this area had rich plant species.Among them,the number of shrub species were the most and the herb were the least.It totaled 54 families,91genera and 140 species (including variations) of vascular plant species.The vertical structure of community was relatively beautifully layered which could be di-vided into tree layer,shrub layer,herb layer,and a definite number of interstratum plants besides.The dominant species in tree and herb layer were quite obvious,but the dominant species in the shrub layer of the differences was the opposite.The change trend of richness index(R1 and R2 )、diversity index(D and H)and evenness index (J1 and J2 )were the same (shrub layer>tree layer>herb layer).T-test results showed that the differences of the spe-c

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全面和正确地认识群落结构特征与景观美学质量的关系，对揭示森林景观美学质量的形成机制和进行景观质量提升具有重要意义。采用美景度评价法（Scenic Beauty Estimation, SBE）和回归分析，从林分水平结构、垂直结构和物种组成等群落结构特征层面，分析群落结构特征与景观质量的关系。结果表明：群落结构要素对美景度贡献大小顺序依次为Pielou均匀度指数＞乔木层密度＞Shannon-Wiener多样性指数＞林层数＞乔木层平均高度；Pielou均匀度指数和乔木层密度与美景度呈负相关关系，Shannon-Wiener多样性指数、林层数和乔木层平均高度与美景度呈正相关关系；物种丰富、乔木层密度较小、林层数多、乔木层平均高度较大的林分具有较高的美景度值。根据群落结构和林内景观质量关系得出群落结构优化策略，首先尽可能满足物种多样性和生态系统稳定性的需求，在此前提下从水平和垂直结构等空间配置上，综合运用林分抚育、林下层管理和美学规划等措施，构建出符合生态要求和具有较高美学价值的森林景观。
Forest structure is an important element determining in-forest landscape beauty, and a comprehensive understanding of their relationship may give insight into the management and improvement of scenic areas. Scenic Beauty Estimation (SBE) and regression analysis were used to evaluate landscape beauty of Huashan Scenic Area, Ningming, Guangxi, with forest horizontal and vertical structures, species composition being considered. The results show that landscape beauty was influenced by following factors in a declined order: Pielou index, arbor tree density, Shannon-Wiener index, number of canopy layers, average tree height. The Pielou index and arbor tree density were negatively correlated to the landscape beauty, while Shannon index, number of canopy layers, average tree height were positively correlated to the landscape beauty. Stands with high richness, lower arbor tree density, multiple canopy layers and higher tree height generally had higher landscape beauty. Strategy to up

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根据资料收集和实地调查的数据，对安国市各类绿地绿化植物群落结构与多样性进行分析。结果表明：绿地中重要值大于10％的乔灌木有16种，均为当地适生树种。道路绿地中植物群落多为乔木、或乔灌结构；附属绿地中多为乔灌草、灌草复合结构；公园绿地中乔灌草复合结构。各类绿地中，乔木均匀度指数最高，灌木次之，草本最小；灌木层的多样性指数最高，乔木层次之，草本层最低。
Different vegetation of green space in Anguo City was discussed ,in its plant com-munity and diversity by analyzing the data from field survey .The results showed that there are 16 kinds of trees and shrubs with more than 10% important value in its green specie , which are all well growing local species .The majority of greening plants are arbors ,or ar-bors and shrubs in the road green space .The plant community of subsidiary green space is mostly composited of herbages ,shrubs and arbors or herbages and shrubs .The city park green space is coverd mostly with plant community of herbages ,shrubs and arbors . The Pielou indexes of arbors is the highest and that of herbages is the least .T he highest diversity indexe is from shrubs with the least from herbage .

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