孟加拉涝原地区村林居住的宗教社团偏爱的乔木和灌木树种及使用的造林材料研究

2002年1月至6月对孟加拉涝原地区两个不同的宗教部落(印度教和穆斯林教)的传统家园森林进行了探索性研究,包括印度教和穆斯林教社团对树种(乔木和灌木)的偏爱度、类似性、造林材料及来源、植树地点和间距。研究发现Mangifera indica作为乔木树种,Ocimum sanctum作为灌木树种为印度教社团最喜爱的树种;Artocarpus heterophyllus和Lawsonia inermis分别为穆斯林社团最喜爱乔木树种和灌木树种。两中不同宗教社团选择乔木数种的相同性为86．57％,灌木树种为78．48％。两个宗教部落使用种子和苗木作为造林材料最多。乔木树种的造林材料主要来自家园(39％)灌木树种主要来自自然界(40％)。表3参27。     

Homestead forest resources and their role in household economy: A case study in the villages of Gazipur Sadar Upazila of central Bangladesh

This study examines the species composition, diversity and economic importance of homestead forests in the household economy of central Bangladesh. The study documents 57 homestead forest species and their main usage in 90 households across three villages of Gazipur Sadar Upazila. Homestead forests in Bangladesh comprise a mixture of fruit, timber and bamboo species. While superficially homestead forestry appears unimportant in rural livelihoods, in reality the contribution is huge, both as a source of food security and for other necessary household materials. A clear understanding of the physical characteristics and economic role of homestead forests in rural livelihoods is vital for ensuring sustainable resource management. Income and production of homestead forestry on a per hectare basis are found to vary widely between landholding size classes. Significant relationships are identified between forest performance (production and income) and species richness and education level. Homestead forestry appears to be a potential subsistence income generating land-use practice in the study area. The economic scope of homestead forestry can be further enhanced provided the appropriate species composition of the forest is achieved and the education of forest owners is ensured through targeted management and policy interventions.     

川中丘陵区防护林群落多样性研究

本文对川中丘陵地区主要防护林群落的物种多样性进行研究,结果表明：①该流域共有维管束植物55科,82属,88种,其科、属、种数与四川省乃至全国比较,官司河流域植物区系具有组成简单的特点;②物种丰富度,物种多样性和均匀度指数都是人工林低于天然次生林,纯林林分低于混交林分;③土壤pH值、土壤有机质、土层厚度和人为干扰是影响防护林群落多样性发育的重要制约因子,其中土壤pH值是主导因子,制约着本区防护林群浇的空间分布格局;④林木高度、郁闭度和灌、草层盖度与物种丰富度、物种多样性指数和均匀度指数相关密切,对群落多样性发育的影响较大;而林木胸径与群落多样性指数相关不明显,对群落多样发育的影响不大。     

Distribution and composition of carabid beetle (Coleoptera, Carabidae) communities across the plantation forest cycle—Implications for management

If national afforestation targets are met, the proportion of area under plantation forest cover in Ireland will almost double by the year 2030 to 17%, and will consist of mostly non-native trees. There is an urgent and vital need to assess and to maximise the biodiversity potential of these forests. This study compares carabid beetle (Coleoptera, Carabidae) composition and assemblage patterns across different stages of the forest cycle, in addition to intensive grassland habitats, the habitat the plantation forest will most likely be replacing. The clearfell habitat had the highest median species richness, while the grassland habitat had the highest species diversity, but lowest species dominance. Ordination analysis revealed that the species assemblages of all stages of the forest cycle could be clearly separated from the grassland habitat, while differences were also observed between forest stages. Canonical correspondence analysis revealed that the most significant factors influencing carabid community composition were percent cover of ground vegetation and mosses, and also percent soil moisture. Differences in species with varying physical traits and microhabitat preferences were also observed between habitats, with larger, brachypterous species positively associated with increasing canopy cover and smaller macropterous species displaying the opposite pattern. The presence and abundance of forest-associated species increased with increasing plantation age, with a corresponding decrease in open habitat-associated and generalist species. The results of this study suggest that at the landscape scale, a variety of different aged forest stands would maximise the biodiversity potential of the planned afforestation.     

Lianas and self-supporting plants during tropical forest succession

Lianas (woody vines) are an important component of tropical forests, with a strong impact on forest dynamics, but their responses during forest succession have received relatively little attention. Here, we present an analysis of the changes in stem density, biomass, and species richness of lianas and self-supporting plants during tropical forest succession. We surveyed lianas ≥0.5 cm diameter at breast height (dbh) and self-supporting plants ≥2.5 cm dbh in 0.1 ha inventory plots in a chronosequence of 30 sites in northeastern Costa Rica, 23 sites on abandoned pastures 10–44 years of age, and seven sites in old-growth forest. Stem density of self-supporting plants showed no predictable chronosequence trend, but liana stem density declined significantly with forest age. Aboveground biomass of self-supporting vegetation increased rapidly during succession, with forests 31–44 years exhibiting higher levels of biomass than old-growth forests. Liana biomass accumulated more slowly, with the highest levels in old-growth sites. Species richness of self-supporting vegetation increased significantly during succession, but species richness of lianas showed no change or a slight decline with forest age, depending on the method of assessment. The differences between tree and liana responses during succession stem from the unique physiology and life history traits of lianas.     

Are gullies best for biodiversity? An empirical examination of Australian wet forest types

A relatively common observation in forest environments has been that gullies support higher species richness and individual abundance than elsewhere in the landscape. We completed a detailed case study of birds to contrast species richness and assemblage composition between gullies and other parts of the topography of landscapes in three closely related and spatially adjacent wet ash forest types – those dominated by Mountain Ash (Eucalyptus regnans), Alpine Ash (E. delegatensis) or Shining Gum (E. nitens) – in the Central Highlands of Victoria, south-eastern Australia. We also quantified the influence of a wide range of other measures of stand structure and plant species composition on the bird assemblage and on individual bird species.     

Assessing the relationships between stand development and understory vegetation using a 420-year chronosequence

The large-scale conversion of old forests to tree plantations has made it increasingly important to understand how understory vegetation responds to such landscape changes. For instance, in some forest types a reduction in understory richness and cover is thought to result from the development of canopy closure in plantations, although there is a paucity of empirical data demonstrating this relationship. We used a 420-year forest chronosequence as a case study to assess the relationship between stand age, tree canopy cover and understory vascular plant richness and composition in the Siskiyou Mountains of Oregon. The chronosequence consisted of six young managed (age 7–44) and nine older unmanaged (age 90–427) stands. All stands were similar in underlying geology, slope, elevation, and aspect. We found a non-linear relationship between stand age and richness, in which richness was highest in the youngest stands, reached a low in mid-aged stands (∼55 years), then increased in the oldest stands. We also found that percent tree canopy cover was correlated with total understory cover, richness, diversity, and species composition. In general, young stands were characterized by high shrub and graminoid cover and old stands were characterized by an abundant herb layer. Our work suggests that a major component of our study landscape is currently entering the forest stage (canopy closure) characterized by low levels of vascular plant species richness and cover. We use our results to discuss the potential effects of future forest management on understory plants.     

中国热带次生林分布、类型与面积研究

热带林的保护问题已受到世界各国的高度重视,由于占世界热带林面积约三分之一的热带次生林,其经济和生态效益通常较差,处于相对被忽视的状态,因此也往往被进一步破坏。将次生林经营纳入可持续经营的轨道,是实现热带林可持续经营目标的重要战略。通过对中国热带森林研究、经营和统计资料的分析,结合本项目实施过程的实地调研取得的结果,文章对中国热带地区次生林分布、面积和类型作了阐述。热带森林主要分布在海南、广东、广西、云南、台湾,以及福建和西藏的部分地区,包括124个县市的全部和50个县市的部分地区。据可认可的资料统计,中国热带林地面积（不含台湾省）约1125．66万hm^2。其中有林地面积1074．49万hm^2,次生林面积544万hm^2。次生林占热带地区林地面积的48．33％,占有林地总面积的50．63％。中国热带林地和次生林的实际数字估计要比这一数值大6％以上,因为中国这几年高度重视林业建设,森林植被特别是热带森林植被恢复得很快,林地和次生林一直在不断增加。热带森林类型主要有：热带雨林（包括湿润雨林、山地雨林）;热带季雨林（包括半常绿季雨林、落叶季雨林、石灰岩季雨林）;南海珊瑚岛植被;海岸红树林等。从森林经理的角度,中国热带次生林的类型可分为：（1）次生阔叶林,包括次生常绿阔叶雨林、次生季雨林和次生季风常绿阔叶林;（2）次生灌木林;（3）次生针叶林;（4）次生红树林及次生珊瑚岛林等四大类型。     

华中神农架箭竹(Fargesia spathacea)群落之海拔多样性

通过对华中神农架海拔1500米至2600米之间11个箭竹样方的研究,阐述了箭竹群落物种丰富度,物种多样性,物种均匀性,生活型谱及群落类型的海拔变化。从最低样方(1680米)到最高样地(2570米),微管束植物从30种降为7种,服从线性模型：Y=55.99-1.83X(R2=0.84,P<0.001);物种多样性从3.18降为1.78,服从线性模型：Y=4.67-0.10X (R2=0.72,P=0.001;物种均匀度在0.83至0.99之间变化,但与海拔并不相关。在生活型谱中,一年生植物,地下芽植物和大高位芽树木的百分比随海拔升高而升高;灌木和中高位芽树木随海拔升高而降低;多年生草本和半灌木与海拔关系不大。箭竹群落可分为5种类型：常绿阔叶林下,落叶阔叶林下,温性针叶林下,寒温性针叶林与混交林下,纯箭竹林。     

热带森林与次生林经营研究

文章综述了世界热带地区的森林资源分布、基本类型、主要特征,以及世界次生林的经营现状和主要经营方式。这些经营方式包括建立自然保护区、生态公益林经营、\"采掘主义\"、限制采伐和伐后更新、\"砍三留七\"法、\"扶持\"式育林法、\"抑制\"式育林法、整体培育法、专门培育法、带状皆伐法、开发欠知名树种、自然更新和封山育林。同时提出了森林分类经营,即按照经营的主要目的将其划分为商品林、公益林和多功能林等基本类型的方法。此外,分析了热带次生林存在的问题,并提出解决这些问题的措施。     

Retention of aspen (Populus tremulae) at final cuttings - The effect of dead wood characteristics on saproxylic beetles

To preserve biodiversity in managed forest landscapes dead and living trees are retained at final cuttings. In the present study we evaluated the effect of these practices for saproxylic (wood-dependent) beetles inhabiting dead aspen trees (Populus tremulae). For saproxylic beetles, tree retention at final cuttings can be expected to be especially valuable for species adapted to sun-exposed dead wood, a substrate that only rarely occurs in well managed forest stands. Therefore, the current evaluation was conducted as a comparison of species richness, species density (number of species per sample), assemblage composition and occurrence of individual species between clear-cuts, where aspen trees were retained, and closed forest stands with aspen trees. The study was conducted in central Sweden and the beetles were sampled by sieving of bark from CWD (coarse woody debris) of aspen. There was no significant difference in rarefied species richness between forest and clear-cut sites. Species composition differed significantly between the two stand types. Generalized linear mixed-effects models predicted the species density to be 34% lower in CWD objects in forest sites than on clear-cuts. This pattern could partly be explained by differences in CWD diameter, decay class and bark types between the two stand types (clear-cut/forest). Stand type was a significant predictor of occurrence in individual CWD objects for 30% of analysed individual beetle species. For all species except one, the variable stand type predicted higher occurrence on clear-cuts than in forest stands. To conclude, our results demonstrate that retention of aspen on clear-cuts contributes to population recruitment of a different assemblage of species than CWD within stands.     

不同采伐方式对兴安落叶松林林下物种多样性的影响

在大兴安岭林区不同采伐区选择典型样地,采用Patrick丰富度指数、Simpson多样性指数、Shannon-Wiener多样性指数及Pielou均匀度指数,研究了不同采伐方式对兴安落叶松林林下物种多样性的影响。结果表明:适度的间伐干扰有利于生物多样性的提高,随着采伐干扰强度和频度的增大,生物多样性会下降;皆伐更新不利于生物多样性的保护,会降低物种多样性指数,改变生物多样性结构;渐伐符合森林更新及林下重要物种对外界环境变化适应的要求,有利于生物多样性和整个生态系统的稳定。     

中国热带次生林生产潜力与经营模式研究

在完成对中国热带地区次生林现状、经营情况的相关资料分析和重点地区的实地调查后认为：从目前次生林的生态效益来看,对比人工林,次生林在涵养水源、保持水土、维持地力等方面表现出较好的效益;与原始林比较,次生林在吸收CO2和释放O2和改良土壤的功能相对强,而固土效益和蓄水效益则较低。在经济效益方面,通过样地的调查分析,由于缺乏经营,次生林的木材生产能力相当低,单位面积平均蓄积量约仅78m^3／hm^2,为世界平均森林蓄积水平的68％左右。通过经营,中国次生林有较大的生态和经济潜力开发空间。由于中国经济仍然比较落后,特别是在农村,环境保护和生存问题都很突出。因此,要保护和发展次生林,只有选择生态和经济效益同时兼顾的经营模式,才能实现其可持续性。通过一年的调研,根据中国的经营传统和结合现实状况,归纳出目前在中国可以普遍推广的三个主要经营模式,即：社区综合经营模式、天然林的恢复与重建模式和经济物种套种经营模式。     

华中神农架箭竹(Fargesia spathacea)群落之海拔多样性(英文)

通过对华中神农架海拔1500米至2600米之间11个箭竹样方的研究,阐述了箭竹群落物种丰富度,物种多样性,物种均匀性,生活型谱及群落类型的海拔变化。从最低样方(1680米)到最高样地(2570米),微管束植物从30种降为7种,服从线性模型:Y=55.991.83X(R2=0.84,P<0.001);物种多样性从3.18降为1.78,服从线性模型:Y=4.670.10X (R2=0.72,P=0.001;物种均匀度在0.83至0.99之间变化,但与海拔并不相关。在生活型谱中,一年生植物,地下芽植物和大高位芽树木的百分比随海拔升高而升高;灌木和中高位芽树木随海拔升高而降低;多年生草本和半灌木与海拔关系不大。箭竹群落可分为5种类型:常绿阔叶林下,落叶阔叶林下,温性针叶林下,寒温性针叶林与混交林下,纯箭竹林。图4表2参19。     

长白山北坡不同海拔植物群落物种丰富度估计

应用梯度格局法在长白山北坡海拔700-2600 m 之间,海拔每上升100 m设置一块样地,共20块样地。以具体的样地观测数据为基础,应用刀切法和自助法等非参数估计法对各海拔群落的物种丰富度进行了估计,结果表明,用自助法所得到的物种估计数,与客观实际更为接近。同时,根据各海拔群落观测物种数与估计物种数的差异,进一步验证了最小取样面积的合理性。     

Diversity of filamentous fungi in leaf litter and aerial litter in semi-deciduous forest,Bahia, Brazil

The fungi have wide distribution in ecosystems and can be found colonizing various substrates,where they act as efficient decomposers,participating in cycling of nutrients.The present study aimed to assess the diversity,richness and composition of filamentous fungi in leaf litter and aerial litter in a semi-deciduous forest in the Chapada Diamantina,Bahia,Brazil.Samples of leaf litter and aerial litter were collected monthly from October/2009 to September/2010 in eight installments in the studied area.Those samples were washed,placed in moist chambers and incubated.47 taxa were identified,37 in leaf litter and 35 in aerial litter,with 25 species common to both.A similarity of 69 % according to Sorensen index.The similarity was considered low when the sample points were compared to the same litter.Most fungi showed sporadic intervals.