湘南红壤丘陵区不同植被类型下土壤肥力特征

以自然植被恢复长期定位试验为基础,通过分析自然恢复31a后形成的6个植被类型区(樟树、枫树、梓树、白檵木、唐竹、白茅草)、2个同期种植的人工植被区(湿地松、板栗)以及相邻裸地区0—100 cm土层pH值、有机质及主要养分含量的变化,明确了湘南红壤丘陵区不同植被类型对土壤肥力的影响。结果表明:(1)白茅草和唐竹区的土壤pH值显著高于裸地区,但枫树和白檵木区的土壤酸化明显。(2)土壤有机质、活性有机质、全P、速效P等指标表现为乔木草本灌木,碱解N、全K、速效K表现为灌木乔木草本,全N表现为乔木灌木草本。(3)土壤综合肥力优劣为:枫树区梓树区白檵木区樟树区唐竹区白茅草区湿地松区板栗区裸地区,自然恢复植被比人工植被更有利于土壤肥力的提高。     

雅砻江和大渡河干旱河谷植被物种多样性比较:气候、地形与空间的影响

干旱河谷植被是我国西南横断山区的一类特殊的隐域性生态系统, 影响不同河谷之间植物群落差异的因素与作用大小尚不清楚。本研究调查了四川省雅砻江和大渡河流域干旱河谷段植被组成, 并比较了两个地区在植物多样性上的差别。结果表明: (1)影响两个地区植被类型的主要因素不同, 雅砻江干旱河谷植被主要受海拔和地形(坡度和坡向)影响, 大渡河干旱河谷植被主要受年平均降水量影响。(2)雅砻江和大渡河干旱河谷植物物种丰富度均随着年均温升高而降低。(3)坡向由北至南, 雅砻江干旱河谷灌木、草本物种丰富度减小, 而大渡河干旱河谷灌木、草本丰富度增加。(4)坡度越大, 雅砻江和大渡河干旱河谷灌木的丰富度越高。(5)雅砻江、大渡河干旱河谷植物β多样性受环境距离影响大, 受地理距离影响小。两条江植被间地理隔离效应约为地理距离产生差异的5倍。本研究弥补了干旱河谷研究中对于雅砻江和大渡河干旱河谷植物多样性研究的空白, 为相关区域植被保护提供了参考信息, 同时还为定量估计地理隔离效应对区域间生物多样性差异的影响提供了可行方法。     

云南元谋干热河谷植被恢复初探

根据元谋干热河谷的植被退化、残遗特征,论述了其原生植被类型,并认为呈多顶极分布格局;通过试验表明：元谋干热河谷区只要选择适宜的树种及其正确的造林技术,无论是在砾石层阶地、土石山地和泥岩山地都可以种植乔木成林。     

元谋干热河谷植物区系研究

元谋是我国著名的干热河谷之一。在元谋干热河谷1600米以下的山坡上主要分布着稀树灌草丛植被。经研究计有种子植物78科、266属、399种,其中绝大部分为草本和灌木种类。从种子植物的地理成分分析这里的区系成分带有明显的热带性质,其中出现在元谋的热带属占属总数(不包括世界分布属)的72.3％,温带分布属占26.4％,中国特有分布属占1.3％。这里的区系成分除了与其所处的滇中高原邻近地区关系很密切外,与印度等地的稀树草原也有联系,表现出了区系成分的古老联系和稀树草原植被的残余性。     

云南巧家金沙江干热河谷的植被分类

采用法瑞植物社会学学派的排表法对巧家干热河谷的植被进行系统分类,并以数量分类方法(组平均法)进行验证,结果将当地植被划分为一个群目(order)、两个群属(alliance)、四个群丛(association)。本文还详细探讨了当地植被的生境及区系、生态学特征,同时对比了当地植被与元谋干热河谷植被的异同。     

长白山寒温带风灾区植被受损与灾后变化程度及其影响因素

1986年台风袭击了长白山,在西、南坡的寒温带针叶林和岳桦林带形成了大量林窗.为了探究在强风干扰下寒温带森林植被受损和变化特征,揭示植被受损与灾后变化规律及其影响因子,2017年在长白山海拔1600～1800 m设立研究区.利用遥感资料,对研究区依据植被破坏程度和灾后变化程度进行植被差异分区,并布设了40个样方进行植被调查.结果表明: 按森林结构的受损程度可将长白山寒温带风灾区分为3个等级,轻度破坏、中度破坏和重度破坏,其中,中度破坏区的面积最大,其次是轻度破坏区、重度破坏区.乔木受损差异显著,轻度破坏区、中度破坏区和重度破坏区乔木优势种的数量分别减少20%、50%和85%,岳桦的抗风性大于鱼鳞云杉,大径级岳桦的抗风性大于小径级的岳桦.植被受损程度与坡度的相关性最强,随着坡度的增加,受风灾破坏程度减小.1987—2017年间,长白山寒温带风灾区的植被发生明显变化,根据变化的程度可将研究区分为3个等级:变化快、变化中等和变化慢,其中,变化中等的区域面积最大,其次是变化慢、变化快的区域;植被变化程度与海拔的相关性最强,随着海拔的增加,植被变化变慢.乔木的恢复较慢,鱼鳞云杉略好于岳桦;植被变化主要表现在灌木层和草本层,变化快的区域灌木层发育好于草本层;变化中等的区域草本层发育好于灌木层;变化慢的区域灌木层发育差异大,但草本层总体上表现为低矮稠密.     

金沙江干热河谷(元谋段)的丛枝菌根

用碱解离、酸性品红染色法对金沙江干热河谷(元谋段)中生长的60种植物的丛枝菌根状况进行了调查。结果发现被调查植物中70％的植物形成丛枝菌根,干热河谷自然植物群落中的建群种大多具有丛枝菌根,一些莎草科、蓼科的植物也形成典型的丛枝菌根。丛枝菌根是干热河谷生态系统中的重要组成成分,在干热河谷的植被恢复中,必须同时考虑对地下植物共生真菌进行恢复。     

元江元谋干热河谷土壤氮磷水平对酸角叶片氮磷含量及光合的影响

为了解元江及元谋干热河谷人工栽培酸角的土壤氮磷含量对酸角叶片氮磷含量及光合作用的影响,本研究测定了两个干热河谷区酸角人工林土壤、叶片氮磷含量及光合参数,并使用4种常用的光响应曲线拟合模型(直角双曲线模型、非直角双曲线模型、直角双曲线修正模型、二项式拟合模型)对其进行拟合。结果表明:元江、元谋干热河谷酸角人工林土壤氮磷含量及氮磷比存在显著差异,两地土壤氮含量分别为1.205和0.881 g·kg-1,磷含量分别为0.481和0.177 g·kg-1,氮磷比分别为2.61和5.49;两地酸角叶片氮含量存在显著差异,元江、元谋干热河谷酸角叶片的氮含量分别为17.28和13.51 g·kg-1,而叶片磷含量没有显著差异,分别为1.51和1.18 g·kg-1,叶片氮磷比也没有显著差异,分别为11.80和11.66; 4个光响应曲线拟合模型对两个干热河谷酸角的光响应曲线都有较高的拟合度,但直角双曲线修正模型在低光合有效辐射情况下拟合度最高,而二项式拟合模型在高光合有效辐射情况下拟合度最高,因此表观量子效率(α)、光补偿点(LCP)、暗呼吸速率(Rd)取直角双曲线修正模型的拟合数值,元江、元谋两地酸角的数值分别为0.055和0.060、38.921和8.019μmol·m-2·s-1、1.377和0.404μmol·m-2·s-1;最大净光合速率(Pnmax)、光饱和点(LSP)取二项式拟合模型的拟合数值,两地分别为11.073和6.331μmol CO2·m-2·s-1、3223.2和2532.4μmol·m-2·s-1;元江干热河谷的酸角光合作用显著高于元谋干热河谷,两地土壤磷含量和叶片磷含量是影响酸角光合作用的关键因子。     

几种台湾水果在云南元谋干热河谷区的适应性研究

在云南元谋干热河谷区引种数种台湾水果(番木瓜、番石榴、阳桃、莲雾、火龙果)进行适应性栽培试验。结果表明,引进的台湾水果在植株长势、果实发育及品质等方面表现良好,适应性和抗逆性较强,适宜在金沙江干热河谷地区种植。     

元谋干热河谷植被的类型研究 Ⅰ.群丛以上单位

本文主要用法瑞植物社会学学派的方法对元谋干热河谷植被的群丛以上单位进行划分和研究。经分析,确定了从群目(order)到群丛(association)的一个分类等级系统。整个河谷区的植被可以归入到扭黄茅、坡柳群目(Dodonaeo-Heteropogonetalia contorti)中,下面再分出两个群属(alliance)和九个群丛。经使用模糊聚类分析数学方法验证,分类基本合理。 经研究表明元谋干热河谷1600米以下地区的气候及植被特点与热带的稀树草原(savanna)十分相似,可以称为半自然稀树草原或次生性稀树草原(semi-natural savanna or secondarysavanna)。     

陕北黄土区封禁流域坡面微地形植被特征分异

以陕西省吴起县合沟流域内微地形及原状坡面的植被调查数据为基础,研究浅沟、切沟、塌陷、缓台和陡坎5种黄土高原典型微地形植被特征及其与原状坡面的差异.结果表明： 黄土区封禁流域坡面微地形内植物群落物种组成、数量特征及其多样性存在明显差异.经过12年的自然恢复,研究区域形成以铁杆蒿和茭蒿为优势种的草本群落,伴生种中,陡坎和切沟出现灌木扁核木和柠条,缓台出现湿生性植物芦苇.微地形植被的盖度、平均高度和生物量多优于原状坡面,且以切沟和塌陷最为显著.不同微地形Shannon指数的大小顺序为陡坎＞切沟＞浅沟＞原状坡面＞缓台＞塌陷.     

鹞落坪国家级自然保护区草本植物多样性及空间分布

鹞落坪国家级自然保护区森林群落研究主要集中于乔木层生物多样性、群落组成与结构及其维持机制,但对保护区林下草本层植物多样性及空间结构缺乏研究。以鹞落坪国家级自然保护区内落叶阔叶林11.56 km²永久大样地（以下简称大样地）林下草本植物为研究对象,探讨草本层植物多样性、空间分布格局及优势种的种间联结性和相关性。结果表明：（1）大样地内的草本植物共有52科134属195种,其中百合科、唇形科、堇菜科、菊科与毛茛科草本植物占主导作用。（2）大样地内草本植物优势种明显,多样性指数较高且整体分布较为均匀,其中北部阳坡物种多样性较低,南部阴坡、中部半阳坡的物种多样性较高。（3）七种空间格局分析方法均表明大样地内草本植物优势种呈现聚集分布。（4）大样地内10个草本优势种45个优势种对的χ²检验、联结系数AC检验、Pearson相关系数检验和Spearman秩相关系数检验结果显示,种对间正联结、正相关的数量多于负联结、负相关的数量;Spearman秩相关系数检验更具灵敏性;种间联结强度与相关度较弱,说明林下草本植物种间及与环境之间关系尚未达到相对稳定状态。对鹞落坪落叶阔叶林下草本植物调查与长期监测,为深入研究林下草本植物的生态功能、对林下草本植物资源的保护利用及自然保护区管理提供理论依据。     

金沙江干热河谷山地植被恢复区土壤种子库和地上植被研究

土壤种子库在植物种群动态中起着重要作用。土壤种子库可缓解种群的灭绝过程,保存群落中植物种的表现特征,是植被天然更新的物质基础。通过对金沙江干热河谷山地植被恢复区（包括水平阶、自然坡面、沟底）和未恢复区（包括放牧地）的土壤种子库和地上植被的组成、大小及多样性进行比较研究表明,植被恢复区土壤种子库和地上植被的密度、丰富度、多样性及均匀度均大于未恢复区。恢复区地上生物量要远大于未恢复区。水平阶和各类型间的土壤种子库密度与地上植被密度差异显著。土壤种子库中草本植物占很大比例。孔颖草和扭黄茅是土壤种子库和地上植被的两大优势种,两者的个体数量、重要值及生物量最大。土壤种子库和地上植被有较高的相似性,且随着恢复程度的加深,相似性有增高的趋势;土壤种子库密度和地上植被密度之间关系可以用二次和三次曲线拟合。     

The relationships between vegetation type and topography in Lassen Volcanic National Park

The relationships between topographic features and the relative abundances of vegetation types were analyzed for the mid-montane conifer forests, the upper montane conifer forests and the alpine areas of Lassen Volcanic National Park in the Cascade Range of northern California using Landsat Thematic Mapper data. Vegetation types were identified from Landsat Thematic Mapper data and included pine, fir, montane chaparral, willow/alder and herbaceous communities. Topographic features including aspect, slope steepness, slope configuration (i.e., convex, straight or concave) and slope position (i.e., ridge top to valley bottom) were computed from USGS Digital Elevation Models. The distribution of montane chaparral was consistent with its dependency on fire with chaparral communities being more abundant on more xeric aspects and on steeper and more xeric slope configurations. Slope position was important in determining the distribution of willow/alder communities which were more abundant in valley bottom locations. Both slope steepness and slope position affected the abundance of herbaceous communities. Herbaceous communities were: (1) more prevalent on steeper slopes due to the distribution of dicotyledonous forb species; and (2) more abundant in valley bottoms due to the distribution of monocotyledonous species in wet meadows. Pines and firs were separated along a gradient of slope steepness with the firs being more abundant on steep slopes and the pines being more abundant on shallow slopes. In the alpine areas above 2350 m, the abundance of most vegetation types declined with increasingly mesic aspects. This decline may be related to the prolonged persistence of snow in areas of less intense solar radiation.     

Soil seed bank and aboveground vegetation within hillslope vegetation restoration sites in Jinshajing hot-dry river valley

Soil seed bank plays an important role in the composition of different plant communities, especially in their conservation. Although soil seed bank, aboveground vegetation and their relationship have been the subject of much recent attention, little is known about the size and species composition of the soil seed bank and about the aboveground vegetation in the semiarid hillslope grasslands. There is limited understanding of how these components interact to determine the importance of seed banks in regeneration. In this study, the size and species composition of a soil seed bank and aboveground vegetation have been assessed in an experiment using 36 vegetation quadrats and 108 soil samples in terrace, slope, gully, and grazing land. This land represents a range of habitats within a hillslope grassland in Jinshajing hot-dry river valley of Yunnan, China. Terrace, slope, and gully represent restored sites and grazing land typifies unrestored sites. Twenty-one taxa in the seed bank were identified with a median and median density of 7 species/m² and 5498 seeds/m², respectively, whereas in the aboveground vegetation, 19 species were observed with a median and median density of 6 species/m² and 1088 plants/m², respectively. Both seed bank density and aboveground vegetation density among grazing land, gully, slope, and terrace differed significantly. There was an absolutely high proportion of herbaceous species in the seed bank and aboveground vegetation. Gramineae predominated over both seed bank and vegetation. The most frequent seeds and plants were Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv that had the highest individual number, importance value, and biomass. In the seed bank, the seeds of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 50.68% and 33.10% of the total seeds, respectively. In the aboveground vegetation, the individual number of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 55.66% and 29.86% of the total, respectively. The biomass of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for more than 70% of the total, reaching 206.71 g/m² and 147.76 g/m², respectively. Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv had the highest importance value of 193.01 and 159.99, respectively. Density, biomass, species richness, species diversity, and evenness were the highest in terrace land, whereas these were lowest in grazing land. Similarities between the seed bank and the aboveground vegetation were moderately high and not very different among slope, gully, and terrace lands, while for grazing land, they tended to increase when the restorative stage progressed. This result contrasts with some other studies where the seed bank contributes very little to the seedling flora and the vegetative growth clearly overwhelms sexual reproduction. The hypothesis about significant functional correlation between soil seed bank density and aboveground vegetation density is conformed. Correlation between soil seed bank density and aboveground vegetation density can be described in quadratic and cubic curves. The strong similarity between the vegetation and the seed bank is attributed to a large proportion of the species Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv., which are seed profusive and whose seeds have a significant viability in the ground. The high density, biomass, species richness, species diversity, and uniformity of the reclaimed site are related to the sufficiency of heat and water supplies for species establishment and growth in the site, which partly reflects the effective efforts for hillslope grassland restoration. It is believed that the efforts for vegetation restoration have altered the microhabitat conditions of the site and have provided a favorable habitat for species to establish and grow.     

伊犁河谷北坡垂直分布格局及其与环境的关系——一种特殊的双峰分布格局

针对伊犁河谷北坡山地的植物多样性和土壤因子沿海拔的分布方式进行研究。对研究地海拔1000-2200m植物和环境特征进行调查,选取群落样地总数为44个,共调查到植物种155种,其中乔木7种、灌木18种、草本130种,调查到的群落类型完全涵盖了研究区所有沿海拔上升的群落类型。通过NLFS高级模拟显示总的物种丰富度、Simpson指数、Shannon-Wiener多样性指数、Pielou均匀度指数都与海拔呈现先升高后降低,再升高的一个特殊分布格局。出现了两个较高的物种丰富度地带,其中一个是低山荒漠到落叶阔叶林,另一个是山地草原到针叶林带。土壤养分和盐分也表现出了类似多样性的分布格局。通过PCA和相关分析表明,环境因子控制着物种丰富度和它的分布方式。水分在低海拔比较重要,在高海拔温度比较重要,而由于逆温层的作用,在较高海拔的针叶林带物种多样性出现了上升。物种丰富度与土壤总盐呈现显著负相关关系(r=-0.343),与土壤全盐也呈现显著负相关关系(r=-0.341)。Simpson指数与土壤pH值呈现显著负相关关系(r=-0.465)。Shannon-Wiener指数与土壤电导率呈现显著负相关关系(r=-0.367)。Pielou均匀度指数与土壤电导率呈现极显著负相关关系(r=-0.477),总之,多样性指数和土样盐分表现出了强相关性。这个研究为伊犁河谷植被与植物资源的保护和利用提供重要的科学依据,为河谷区山地植被与环境关系提供基础科学理论,为山地退化植被的修复提供参考案例和可借鉴的基础性数据。     

佛坪国家自然保护区地面生苔藓植物物种多样性

通过对秦岭南坡佛坪国家自然保护区地面生苔藓植物的调查,采用相似性系数、重要值、多样性指数对其进行物种多样性的研究。结果表明:29个样地内地面生苔藓植物共33科69属189种,包括苔类植物7科8属15种和藓类植物26科61属174种,其中青藓科是最优势的科。落叶阔叶栎(Quercus)林下地面生苔藓植物的物种多样性最高,其次是落叶阔叶桦(Betula)林带、竹林、针叶林和沟谷岩石,杜鹃(Rhododendron)灌丛带的最低。落叶阔叶栎林带和落叶阔叶桦林带的种相似性最高,杜鹃灌丛与其它植被带的种相似性都很低。研究表明秦岭南坡的佛坪国家自然保护区内,低山地区的落叶阔叶栎林带是该地区苔藓植物多样性的分布中心,是物种多样性保护的关键地带;亚高山地区杜鹃灌丛带的苔藓植物物种多样性虽然不高,但种类明显不同于别的地带,所以也应是苔藓植物多样性保护值得注意的地带。     

Soil seed bank and aboveground vegetation within hillslope vegetation restoration sites in Jinshajing hot-dry river valley

Soil seed bank plays an important role in the composition of different plant communities, especially in their conservation. Although soil seed bank, aboveground vegetation and their relationship have been the subject of much recent attention, little is known about the size and species composition of the soil seed bank and about the aboveground vegetation in the semiarid hillslope grasslands. There is limited understanding of how these components interact to determine the importance of seed banks in regeneration. In this study, the size and species composition of a soil seed bank and aboveground vegetation have been assessed in an experiment using 36 vegetation quadrats and 108 soil samples in terrace, slope, gully, and grazing land. This land represents a range of habitats within a hillslope grassland in Jinshajing hot-dry river valley of Yunnan, China. Terrace, slope, and gully represent restored sites and grazing land typifies unrestored sites. Twenty-one taxa in the seed bank were identified with a median and median density of 7 species/m² and 5498 seeds/m², respectively, whereas in the aboveground vegetation, 19 species were observed with a median and median density of 6 species/m² and 1088 plants/m², respectively. Both seed bank density and aboveground vegetation density among grazing land, gully, slope, and terrace differed significantly. There was an absolutely high proportion of herbaceous species in the seed bank and aboveground vegetation. Gramineae predominated over both seed bank and vegetation. The most frequent seeds and plants were Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv that had the highest individual number, importance value, and biomass. In the seed bank, the seeds of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 50.68% and 33.10% of the total seeds, respectively. In the aboveground vegetation, the individual number of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for 55.66% and 29.86% of the total, respectively. The biomass of Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv accounted for more than 70% of the total, reaching 206.71 g/m² and 147.76 g/m², respectively. Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv had the highest importance value of 193.01 and 159.99, respectively. Density, biomass, species richness, species diversity, and evenness were the highest in terrace land, whereas these were lowest in grazing land. Similarities between the seed bank and the aboveground vegetation were moderately high and not very different among slope, gully, and terrace lands, while for grazing land, they tended to increase when the restorative stage progressed. This result contrasts with some other studies where the seed bank contributes very little to the seedling flora and the vegetative growth clearly overwhelms sexual reproduction. The hypothesis about significant functional correlation between soil seed bank density and aboveground vegetation density is conformed. Correlation between soil seed bank density and aboveground vegetation density can be described in quadratic and cubic curves. The strong similarity between the vegetation and the seed bank is attributed to a large proportion of the species Bothriochloa pertusa (L.) A. Camus and Heteropogon contortus (L.) Beauv., which are seed profusive and whose seeds have a significant viability in the ground. The high density, biomass, species richness, species diversity, and uniformity of the reclaimed site are related to the sufficiency of heat and water supplies for species establishment and growth in the site, which partly reflects the effective efforts for hillslope grassland restoration. It is believed that the efforts for vegetation restoration have altered the microhabitat conditions of the site and have provided a favorable habitat for species to establish and grow.     

Effects of competition and indirect facilitation by shrubs on <Emphasis Type="Italic">Quercus robur</Emphasis> saplings

Indirect facilitation by shrubs has been suggested as a cost-effective way of regenerating oaks in forests of conservation interest. In this study, we tested whether shrubs can enhance growth in pedunculate oak (Quercus robur) by suppressing herbaceous competitors. We studied interactions between young oaks, shrubs, and/or herbaceous vegetation in an open-field experiment, in southern Sweden, over the first 3 years after planting. Oak saplings were grown in four competition treatments: no competing vegetation; with herbaceous vegetation; with shrubs; and with both herbaceous vegetation and shrubs. Competition from shrubs and herbaceous vegetation both reduced stem diameter and biomass accumulation, but they affected biomass partitioning differently. Saplings grown with competition from shrubs partitioned biomass primarily into height growth, while those saplings exposed to competition from herbaceous vegetation invested a relatively higher proportion in root growth. Competition between shrubs and herbaceous vegetation reduced the above-ground biomass of the herbaceous vegetation, resulting in an indirect facilitative effect for the oaks during the first 2 years after planting. However, during the third year, shrubs had a negative effect on biomass accumulation. In summary, results from this study suggest that shrubs indirectly facilitate biomass accumulation of oak saplings by suppressing herbaceous vegetation, possibly by reducing competition for below-ground resources. However, owing to the relatively short duration of positive net outcome for the oak, we recommend that a longer-term assessment of the interaction between oak regeneration and neighboring shrubs be made before the outcome of this study is applied to practical forestry.     

Vegetation patterns and ecological factors in the Ili River Valley,Xinjiang, China

The Ili River Valley is located in western Xinjiang as a ‘wet island’ in an arid region, and is rich with unique plant species. In this paper, TWINSPAN (two‐way indicator species analysis) and DCCA (detrended canonical correspondence analysis) were performed to analyze the vegetation patterns and influential factors based on data from a field investigation in the mountainous region of the valley. 259 species were recorded in the 85 plots, up to 235 species all appeared in the herb layer, and species of woody plants were very limited. The species composition varied widely between the northern slope and the southern slope. 35 plots on the northern slope were clustered into 10 groups, and 50 plots on the southern slope were clustered into 11 groupes. The DCCA ordination indicated that elevation as a compound factor was the critical driver of species composition on both the slopes. The vegetation patterns were also related to slope gradient, aspect, soil water, soil pH, organic matter and total nitrogen. Available phosphorus and available potassium were important factors on the southern slope only, maybe because of the appearance of shrubs there. The proportion of variation explained was 49.54% on the northern slope and 41.08% on the southern slope. Edaphic variables were more important than topographical variables on the northern slope, while topographical variables seemed to be more influential on the southern slope.