不同密度油松飞播林灌草多样性与林分空间结构关系

林下植被是森林生态系统的重要组成部分,物种多样性和林分空间结构是评估森林生态系统功能和林分经营质量的关键指标。本文以44年生油松飞播林为研究对象,通过典型样地调查,运用单因素方差分析和相关分析,分析林分密度对油松飞播林灌草多样性和林分空间结构的影响。结果表明:(1)林分密度对灌草多样性指数影响差异显著,灌草多样性指数均在低密度的样地中达到最大值。(2)混交度和密集度受林分密度影响显著,而林分密度对乔木胸径和树高的影响体现在林分水平上,而非空间结构单元中。(3)林分空间结构与灌草多样性之间有密切联系,影响林下植被多样性的最主要因子是乔木层混交度。因此,未来在飞播林经营活动中,调整林分密度的同时,应综合考虑林木分布格局,兼顾灌草多样性保护。     

Wildland fires and moist deciduous forests of Chhattisgarh,India: divergent component assessment

We studied moist deciduous forests of Chhattisgarh, India （1） to assess the effect of four levels of historic wildland fire frequency （high, medium, low, and no-fire） on regeneration of seedlings in fire affected areas during pre and post-fire seasons, （2） to evaluate vegetation struc- ture and diversity by layer in the four fire frequency zones, （3） to evalu- ate the impact of fire frequency on the structure of economically impor- tant tree species of the region, and （4） to quantify fuel loads by fire fre- quency level. We classified fire-affected areas into high, medium, low, and no-fire frequency classes based on government records. Tree species were unevenly distributed across fire frequency categories. Shrub density was maximum in zones of high fire frequency and minimum in low- frequency and no-fire zones. Lower tree density after fires indicated that regeneration of seedlings was reduced by fire. The population structure in the high-frequency zone was comprised of seedlings of size class （A） and saplings of size class （B）, represented by Diospyros melanoxylon, Dalbergia sissoo, Shorea robusta and Tectona grandis. Younger and older trees were more abundant for Tectona grandis and Dalbargia sis- soo after fire, whereas intermediate-aged trees were more abundant pre- fire, indicating that the latter age-class was thinned by the catastrophic effect of fire. The major contributing components of fuel load included duff litter and small woody branches and twigs on the forest floor. Total fuel load on the forest floor ranged from 2.2 to 3.38 Mg/ha. The netchange in fuel load was positive in high- and medium-frequency fire zones and negative under low- and no-fire zones. Repeated fires, how- ever, slowly reduced stand stability. An ecological approach is needed for fire management to restore the no-fire spatial and temporal structure of moist deciduous forests, their species composition and fuel loads. The management approach should incorporate participatory forest manage- ment. Use of c     

Correlations between canopy gaps and species diversity in broad-leaved and Korean pine mixed forests

Regeneration of tree species associated with canopy gaps in broad-leaved Korean pine forests was investigated. Species diversity in gaps and under closed canopy was compared, the relationship between biodiversity and gap structure was analyzed. Results indicate that there were significant differences between tree species diversity in gaps and that under canopy (p<0.01). In terms of Shannon-Wiener index, evenness index, and abundance index, the biodiversity in gap community were higher than those under forest canopy in regeneration layer. In terms of Simpson’s dominance index, the dominance of certain species in the regeneration layer increased from gaps to closed canopy (p<0.01). In contrast, trends of biodiversity changes of succession layer in gaps and under closed canopy were opposite. Tree species diversity of different layers reacted directly to the change of gap size class. For example, Shannon-Wiener index and abundance index is higher and Simpson’s dominance index is the lowest in succession layer of medium-size gap (100–250 m²) in the broad-leaved Korean pine forest of Changbai Mountains. Shannon-Wiener index reached the highest in a size of ≥250 m² and <100 m², reached the lowest in a size of 200–250 m² in the regeneration layer. Simpson’s dominance index reached its maximum when the gap size was between 200 and 250 m². Generally, species of different layers reacted differently to the changes of gap size classes. The gap size class with more seedlings did not correspond to size class containing more medium-size trees. Tree species diversity indices in the two layers behaved reciprocally during the development process of forest gaps. __________ Translated from Chinese Journal of Applied Ecology, 2005, 16(12): 2,236–2,240 [译自: 应用生态学报, 2005, 16(12): 2,236–2,240]     

燕山山脉天然次生油松林群落物种多样性及生态位分析

通过植物群落学的调查方法,对位于冀北山地河北省围场县木兰围场自然保护区内不同立地条件下油松(Pinus tabulaeformis Carr.)天然次生林的群落特征、物种多样性及物种生态位进行了研究。结果表明:在木兰围场自然保护区内共记录到乔木树种1种,灌木6种,草本30种。灌木层和草本层的α多样性指数在一定海拔梯度下所呈现的趋势大致相同,都是比较典型的双峰曲线。随着海拔差的增大,群落间β多样性指数均呈逐渐增大的趋势。灌木层中土庄绣线菊(Spiraea pubescens Turcz.)的生态位宽度最大,草本层中披针苔草(Carex lanceolata Boott)、林地早熟禾(Poa nemoralis Linn.)和小红菊[(Dendranthema chanetii(Lvl.)Shih)]的生态位宽度最大。海拔1125m地段生态位重叠度最大的种群为照山白(Rhododendron micranthum Turcz.)和女娄菜(Melandrium apricum(Turcz.)Rohrb.),海拔1250m地段生态位重叠度最大的种群为细裂叶蒿(Artemisia tanace-tifolia Linn.)和阴地蒿(Artemisia sylvatica Maxim.),海拔1325m地段生态位重叠度最大的种群为披针苔草和隐子草(Cleistogenes caespitosa Keng)。     

Assessment of tree species diversity and its distribution pattern in Pachamalai Reserve Forest,Tamil Nadu

An increased understanding of the importance of forest diversity for ecosystem services such as medicine, wood, climate control, etc., has lead to greater interest in the study of forests. This study aims to analyze the diversity, composition, and distribution pattern of tree species in Pachamalai Reserve Forest in the Eastern Ghats of Tamil Nadu State. Data were collected in the quadrant method, where 10 × 10 m² plots at different altitudes from 230 to 930 m with 50-m regular intervals were plotted. A total of 73 tree species belonging to 35 families with the density of 1,372 individuals were enumerated from 3 ha. Overall, the most dominant tree species family was Fabaceae (21 species). The highest number in terms of density of tree species was observed for Pongamia pinnata and the most dominant on the basis of basal area was Tamarindus indica. The species inventory was calculated by Shannon-Weiner index (3.916), Simpson index (0.0206), and Margalef index (9.9667). With the increasing altitudinal gradient, the maximum species richness was observed in the middle elevation zone from 580 to 780 m. The results from the study could be helpful for monitoring and sustaining the forest resources, and important in preventing the loss of biodiversity and mitigating climate change.     

北京怀柔山区油松人工林群落特征及物种多样性

从北京市植物种质资源调查数据中选取了48个样地对怀柔山区的油松人工林群落进行分析,得到怀柔山区油松人工林平均每公顷蓄积为82.8 m3,平均株数密度为2 083株/hm2。采用《中国植被》的分类原则将48个600 m2的样地分为5个群丛组,15个群丛。计算了各群丛不同层次上的丰富度指数、Shannon-Wiener指数、Simpson指数、Pielou均匀度指数。结果表明,油松人工林不同林分蓄积、胸高断面积、林分密度差异比较大,油松人工林群落的组成成分比较简单。H表现为草本层〉灌木层〉乔木层,丰富度指数和均匀度指数的趋势和H相近,D则相反。     

Composition and characteristics of natural secondary forests in Shenzhen,South China

The composition and structure of five natural secondary forests in Shenzhen were studied based on data of plots and were compared with Hong Kong zonal forest, so as to detect their succession stage and species diversity level. According to succession process of subtropical forest and ecological characteristics of dominant species, the authors speculate that five communities are at different stages. Sinosideroxylon community dominated by heliophilous evergreen broad-leaved tree (Sinosideroxylon wightianum) and conifer tree (Pinus massoniana) is at the third stage. Itea Acronychia community dominated by two evergreen broad-leaved heliophytes (Itea chinensis and Acronychia pedunculata) is at the fourth stage. The others, i.e., Schefflera,Sterculia and Cleistocalyx Sterculia community are at the fifth stage where some mesophytes are dominant but heliophytes have a weighed percentage of importance value. Due to succession stage and different forest management and conservation models, the species diversity of five communities is significantly lower than that of Endospermum community in Hong Kong. The values of Shannon-Wiener index and Pielous evenness index of five communities are 2.04-2.953 and 64.2%-74% respectively, but those of the Endospermum community are 4.74 and 79％ respectively. The current situation of these communities suggests that the necessary measures should be taken to protect and restore the communities.     

择伐后长白山北坡天然次生林乔木种多样性的变化动态

通过调查了不同时期择伐后形成的长白山北坡天然次生林的群落特性,研究了28年恢复期间乔木种多样性的变化动态。结果表明:(1)天然次生林内林分的乔木种丰富度S变化较小,始终保持在18-22;(2)在次生林内更新层、演替层及林分的Simpson指数D变化趋势基本类似,主林层在受到干扰后的前15年恢复期Simpson指数D缓慢减小,第15年以后变化比较小;(3)天然次生林的多样性指数变化较小,Shannon-Wiener指数(H)变化幅度始终保持在原始林的H±10%以内。图3表1参14。     

石家庄山区植物群落结构及物种多样性研究

通过对石家庄山区石包垴核桃楸林中调查所涉及到的27种植物的数量特征进行分析,发现核桃楸、细叶苔草、全叶紫堇等植物的重要值较高,在群落中占据明显优势。运用物种丰富度指数(S)、Shannon-Wie-ner多样性指数(H)、Sinpson多样性指数(D)、Pielou均匀度指数(Jsw、Jsi)指标,研究了该区的物种多样性,结果表明:丰富度指数和多样性指数均表现为:草本层>乔灌层,均匀度指数表现为:乔灌层(Jsw)>草本层(Jsw)。研究中对天然林和人工林物种多样性进行了比较,结果为草本层:天然林>人工林,乔灌层:人工林>天然林,总体多样性指数为:天然林>人工林。瑙基耶尔(Raunkiaer,1934)生活型谱分析结果为:地面芽植物为44.44%,占居优势地位,隐芽植物次之,为33.33%,高位芽植物和1年生草本植物较少,无地上芽植物。     

肯尼亚泰塔山区东部弧形山云层森林的外来森林与本土森林树种多样性、丰富度和相似性比较(英文)

对肯尼亚东南部泰塔(Taita)山区的3片破碎的森林进行了树种生物多样性评估,比较外来的松树、柏树、桉树人工林的物种多样性以及外来树种森林和本土森林物种多样性。研究地点为Ngangao(120 hm2)、Chawia(86 hm2)和Mbololo(185 hm2)。采用Y型设计设立32个样区,包含65个小样区。按树种记录每个小样区胸高直径5cm和5cm以上的幼树,同时也记录了各树木的更新情况(幼苗和树苗)。用 Shannon-weiner指数计算了物种的多样性和均匀度。导处的 Shannon指数被进一步转化成有效的数值,用于展示物种多样性的差别幅度。为了评估物种多样性的差别,进行单因素方差分析,为了分离均值,分别用Tukey HSD法和Duncan检测法验证偶数和奇数样品。采用Jaccard相似指数评估物种的类似性。共有58个树种的林木密度变化在每公顷10到2000棵树之间。森林类型和立地之间的物种多样性存在显著差异。本地森林的物种多样性比外来树种森林高;Chawia立地的物种多样性比Nganga和Mbololo立地高,且更新的树种数量也比其他2个立地多,包括野柠檬木(Xymalos monospora)、黑皮密花木(Rapanea melanophloeos)、和(几内亚蒲桃(Syzygium guineense),这些树种具有低干扰属性。这些发现说明,本地森林物种多样性比较高,正如热带地区所预期。Chawia立地的物种多样性高说明此地经历干扰比其他2个立地大。在Chawia地区发现有低干扰树种更新,说明有长期土壤种子库的存在。在Nganga和Mbololo地区发现的外来树种样地上的更新较差情况,可能是缺少种子库所致,因为很多人工林是造在裸地上(如Nganga地区),或者是因为某些树种固有的生理特性(相生相克)抑制了其他树种的更新。     

Effects of selection cutting on the forest structure and species diversity of evergreen broa-leaved forest in northern Fujian, southern China

The short-term effects of selection cutting of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The results showed that selection cutting of low and medium intensities caused little variation in the forest structure. After cutting, the dominant species retained their leading status in the community. However, the community structure changed significantly following selection cutting of high and extra-high intensities; the status of the dominant species of the community declined dramatically. Some tree species began to disappear from the sampling plots. Except for extra-high intensity cutting, the diversity of tree species did not change significantly for the other three cutting intensities. However, the evenness of the stands was very different among the four kinds of cutting plots. For low and medium intensity selection cutting, the evenness declined slightly. For extra-high intensity selection cutting, the evenness increased to some extent, which might be due to a more even distribution of tree species after cutting. Cutting operations resulted in some adverse reactions to development of arborous species diversity of evergreen broad-leaved forest, particularly serious damage to the forest canopy. But the rational selection cuttings, which may benefit the restoration and maintenance of species diversity over a long period and may come about from the variations in environmental factors such as sunlight, temperature and humidity.     

Effects of selection cutting on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian, southern China

The short-term effects of selection cutting of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The results showed that selection cutting of low and medium intensities caused little variation in the forest structure. After cutting, the dominant species retained their leading status in the community. However, the community structure changed significantly following selection cutting of high and extra-high intensities;the status of the dominant species of the community declined dramatically. Some tree species began to disappear from the sampling plots. Except for extra-high intensity cutting, the diversity of tree species did not change significantly for the other three cutting intensities. However, the evenness of the stands was very different among the four kinds of cutting plots. For low and medium intensity selection cutting, the evenness declined slightly. For extra-high intensity selection cutting, the evenness increased to some extent,which might be due to a more even distribution of tree species after cutting. Cutting operations resulted in some adverse reactions to development of arborous species diversity of evergreen broad-leaved forest, particularly serious damage to the forest canopy. But the rational selection cuttings, which may benefit the restoration and maintenance of species diversity over a long period and may come about from the variations in environmental factors such as sunlight, temperature and humidity.     

Quantitative stand structure of woody components of homestead forests and its implications on silvicultural management: a case study in Sylhet Sadar, Bangladesh

This study determined existing quantitative stand structure and its implication on silvicultural management of homestead forestry. The results showed that fruit and timber species have importance values of 57% and 43%, respectively, in the study area, which is in contrast to the commonly held view of absolute domination of fruit species. The fruit species were only moderately dominant over timber species in relation to the quantitative stand structure of homestead forests. Two fruit species, Mangifera indica and Artocarpus heterophyllus, contribute about one third of the stand structure, while amongst the timber species Samanea saman and Albizia spp. are the most important species. A simulated evaluation of soil expectation value of homestead forest showed that the existing stand structure would not maximize the financial gain perpetually, in contrast, the quantitative stand structure could be effectively regulated to maximize grower benefit without compromising the existing biodiversity. Optimization of the quantitative stand structure of homestead forests could be achieved by changing the species composition, specifically by increasing the percentage of commercially valuable species like Michelia champaca, Tectona grandis, Artocarpus chapalasha, Gmelina arborea, Litchi chinensis, Citrus grandis, Psidium guajava, Lagerstroemia speciosa, Swietenia mahogany, etc., reducing the percentage of species like Mangifera indica, Artocarpus heterophyllus, Cocos nucifera, Samanea saman, Spondias pinnata, Phoenix sylvestris, etc., and eradicating species like Lannea coromandelica and Ficus benghalensis. It was estimated that the optimal relative density of fruit and timber species that would generate optimal financial benefit would be 40.4% and 59.6%, respectively.     

Woody species composition,diversity and structure of riparian forests of four watercourses types in Burkina Faso

Riparian forests are classified as endangered ecosystems in general,particularly in sahelian countries like Burkina Faso because of human-induced alterations and civil engineering works.The modification of this important habitat is continuing,with little attention being paid to the ecological or human consequences of these changes.The objective of this study is to describe the variation of woody species diversity and dynamic in riparian forests on different type of watercourse banks along phytogeographical gradient in Burkina Faso.All woody species were systematically measured in 90 sample plots with sides of 50 m × 20 m.Density,dominance,frequency and species and family importance values were computed to characterize the species composition.Different diver-sity indices were calculated to examine the heterogeneity of riparian forests.A total of 196 species representing 139 genera and 51 families were recorded in the overall riparian forests.The species richness of individuals with dbh ≥ 5cm increased significantly from the North to the South along the phytogeographical gradient and varied significantly between the different types of riparian forests.Similarity in tree species composition between riparian forests was low,which indicates high beta diversity and reflects differences in habitat conditions and topography.The structural characteristics varied significantly along the phyto-geographical gradient and between the different types of riparian forests.The diameter class distribution of trees in all riparian forests showed a reverse "J" shaped curve except riparian forest of stream indicating vegetation dominated by juvenile individuals.Considering the ecological importance of riparian forest,there is a need to delineate and classify them along watercourses throughout the country.     

石灰岩山地水土保持林的树种选择

在石灰岩山地水土保持立地类型划分的基础上 ,参照相关研究成果 ,通过标准地调查和主要牧草的播种试验 ,以生长量和生物量为指标 ,确定了水土保持林不同立地类型适宜的树 (草 )种     

Plant diversity and phenological pattern in the montane wet temperate forests of the southern Western Ghats,India

Plants diversity and phenological pattern of the trees were monitored in a montane wet temperate forest (shola) in the     

Structure and species diversity of subtropical evergreen broad-leaved forest in northern Okinawa Island, Japan

The structure and tree species diversity of a subtropical evergreen broad-leaved forest in northern Okinawa Island, Japan, were studied. Enumeration of the six sampling plots revealed an average density of 5,580 individuals with DBH≧3.0 cm/ha, having an average basal area of 55 m². The large-size trees of DBH≧20 cm contributed 10% of the total individuals, and 49% of the total basal area. The forest showed a high diversity of tree species, which is comparable to some tropical rain forests. A total of 54 over-story species of 24 families and a total of 63 understory species of 26 families were identified in the six sampling plots. Fagaceae and Theaceae were the most important families;Castanopsis sieboldii, Schima wallichii andDistylium racemosum were the most important species. The diversity index and equitability index of species were 4.15 and 0.72 for the overstory plots, and 4.72 and 0.79 for the understory subplots, respectively. The diversity index for the overstory was significantly correlated to the total basal area of trees over 20 cm DBH (p<0.05) and the importance value ofC. sieboldii (p<0.001), while for understory, the diversity index was not correlated to the structural parameters (allp>0.16). The size distribution pattern and age structure indicated differences in regeneration strategies for canopy dominants. In population dynamics of the succession process,C. sieboldii andD. racemosum were self-maintaining types, andS. wallichii was a gap- or opening-dependent type. This study was made possible by support from the Japanese Ministry of Education, Sciences, Sports and Culture, which provided a Monbusho scholarship to X.N. Xu.     

Forest structure, diversity and regeneration in unburnt and burnt Anogeissus latifolia forests in Garhwal Himalayas

The present study was carried out at two different gradients of unburnt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further categorized into three different elevations, i.e., lower (700 m), middle (850 m) and upper (1000 m). At each elevation, the density of trees, saplings and seedlings was higher at the unburnt sites except for trees at the upper elevation which was higher at the burnt sites. The total basal area of each layer of forest was also higher at the unburnt sites. The study revealed that the lower number of saplings and seedlings at the burnt forest sites might be due to the effect of fire. Most trees in the lower dbh classes were affected by forest fire at the burnt sites which reduced the total density and total basal area of the trees compared to the unburnt sites. The diversity of trees increased with increasing elevation. However, the diversity of saplings and seedlings reduced with increasing elevation.     

Changes in species composition and diversity in the restoration process of sub-alpine dark brown coniferous forests in western Sichuan Province, China

By adopting the concept of space as a substitute for time, we analyzed the dynamics of species composition and diversity of different restoration sequences (20, 30, 40, 50 years) in two secondary forest types in western Sichuan Province, distributed in a northerly or northwesterly direction. The analysis was based on the results of measurements of 50 plots located at elevations between 3100–3600 m. The forests originated from natural regeneration in combination with reforestation of spruce when the old-growth bamboo-dark brown coniferous forests and moss-dark brown coniferous old growth forests were harvested. Similar old-growth dark brown coniferous forests at ages ranging between 160 and 200 years were selected as the reference forests for comparisons. We recorded 167 species of vascular plants from 44 families and 117 genera. There was no significant difference in terms of the number of species among secondary forests. But the importance values of dominant species varied during the restoration processes. The dominant species in the secondary forests is Betula albo-sinensis, while Abies faxoniana is the dominant species in old-growth dark brown coniferous forests. Species richness increased significantly with restoration processes. It increased quickly in secondary forests during the period from 30 to 40 years, but decreased significantly in the old-growth dark brown coniferous forests. The species richness among growth forms decreased in the following order: herb layer > shrub layer > tree layer. The maximum value of the evenness index occurred in secondary forests at age 40 and remained relatively stable in the bamboo-birch forests, but the evenness index tended to decrease in moss-birch forests and slightly increased in the old-growth mossdark brown coniferous forests. There was a statistically significant difference in the eveness index between the tree and shrub layers as well as between the tree layer and the herb layer, but there was no significant difference between the shrub layer and the herb layer. The value of the Shannon index increased over restoration time. In bamboo-birch forests, the maximum value of the Shannon index was 3.80, recorded at age 50. In moss-birch forests, the maximal value was 3.65, reached in this forest at age 30. The value of the Shannon index of old-growth dark brown coniferous forests was recorded between younger secondary and older secondary forests. The value of the dominance index of communities varied. At the first stage of restoration, it increased, and at the end it was decreased. The dominance index of the tree layer had a similar trend as that of the community dominance index, but was more variable. The minimum value of the dominance index of the tree layer in the moss-birch forests reached 20 years earlier than that of the bamboo-birch forests. There was a significant difference among restoration sequences in the α diversity indices except for the dominance index. No significant differences between the two secondary forest types were detected. Over age, the value of the Bray-Curtis index between secondary forest and old-growth dark brown coniferous forest increased. __________ Translated from Scientia Silvae Sinicae, 2007, 43(5): 17–23 [译自: 林业科学]     

Biomass, diversity and composition of epiphytic macrolichens in primary and secondary forests in the subtropical Ailao Mountains, SW China

Epiphytic macrolichen litterfall was collected over 3 years from primary evergreen broad-leaved forests (PF), Populus bonatii secondary forests (PBSF), middle-aged oak secondary forests (MOSF) and old-aged oak secondary forests (OOSF) of the Ailao Mountains in SW China. To assess changes in the epiphyte communities of the subtropical forests, we compared the differences in biomass, species diversity and community structure of epiphytic lichens from the four forest types. A total of 51 species were recorded in this study. Species richness was highest in the PF, while α-diversity was highest in the MOSF. Lichen biomass differed markedly across the four forest types and was highest in the MOSF. The contribution of each dominant species to total biomass, except Nephromopsis ornata, was significantly different among forest types. Moreover, the percent contribution of foliose chlorolichens to litterfall tended to be higher in later-succession forest types, whereas the contributions of cyanolichens and fruticose chlorolichens were lower in these forest types. Compared to the PF, the lichen community structure in secondary forests differed significantly, implying that at least a few hundred years were needed for the restoration of these lichen communities. In particular, nineteen lichens were suggested as indicators, and eleven of them were present in the MOSF. Canonical correspondence analysis (CCA) indicated that the observed differences were mainly attributed to canopy openness and the size of the largest tree, which represented an environmental gradient from exposed to sheltered habitats. The diversity of host tree species was also important in determining the composition and distribution of macrolichens. Our findings support the idea that the maintenance of the forest landscape mosaic of heterogeneous forest types may be an important management practice to maintain or promote the epiphytic lichen community of the subtropical Ailao Mountains.