滇青冈种子的萌发

比较3种打破滇青冈种子休眠方法的结果表明,经40℃处理后的效果最好,发芽率达74.5%.100 mg·L-1的赤霉素浸种处理的次之,发芽率为70.2%.种子种皮切伤和去除种皮后,发芽率增大,分别为96.0%和95.0%,并提早5 d萌发.种子抑制物质实验的结果显示,滇青冈种子的内种皮和种仁含有抑制种子萌发的物质.     

古田山青冈林优势种群生态位特征

利用样方法进行野外调查,每个样地大小20 m×20 m。采用生态位宽度、生态位相似比例和生态位重叠值公式统计分析了古田山自然保护区青冈林优势种群生态位特征。结果表明,古田山青冈林中青冈、马银花、木荷、甜槠、麂角杜鹃等具有较大的生态位宽度,其Bi、Ba分别为0.7974、0.6435、0.6272、0.5908、0.5783和0.7770、0.4012、0.4745、0.4171、0.4303;而光叶石楠和栲树的生态位宽度较小,Bi、Ba仅为0.3966、0.2716和0.1441、0.0825。生态位宽度大的种群间生态位相似比例较高,如青冈与马银花、麂角杜鹃的生态位相似比分别为0.6134、0.6056;反之则低,如光叶石楠和栲树生态位相似比为0.1039。生态位重叠与生态位宽度有一定的联系,高生态位宽度种群间的生态位重叠通常较大,反之则低。     

A population genetic evaluation of ecological restoration with the case study on <Emphasis Type="Italic">Cyclobalanopsis myrsinaefolia</Emphasis> (Fagaceae)

The ultimate goal of ecological restoration is to create a self-sustaining ecosystem that is resilient to perturbation without further assistance. Genetic variation is a prerequisite for evolutionary response to environmental changes. However, few studies have evaluated the genetic structure of restored populations of dominant plants. In this study, we compared genetic variation of the restored populations with the natural ones in Cyclobalanopsis myrsinaefolia, a dominant species of evergreen broadleaved forest. Using eight polymorphic microsatellite loci, we analyzed samples collected from restored populations and the donor population as well as two other natural populations. We compared the genetic diversity of restored and natural populations. Differences in genetic composition were evaluated using measurements of genetic differentiation and assignment tests. The mean number of alleles per locus was 4.65. Three parameters (A, A _R, and expected heterozygosity) of genetic variation were found to be lower, but not significantly, in the restored populations than they were in the natural populations, indicating a founder effect during the restoration. Significant but low F _ST (0.061) was observed over all loci, indicating high gene flow among populations, as expected from its wind-pollination. Differentiation between the two restored populations was smallest. However, differences between the donor population and the restored populations were higher than those between other natural populations and the restored populations. Only 13.5% and 25.7% individuals in the two restored populations were assigned to the donor population, but 54.1 and 40% were assigned to another natural population. The genetic variation of the donor population was lowest, and geographic distances from the restoration sites to the donor site were much higher than the other natural populations, indicating that the present donor likely was not the best donor for these ecological restoration efforts. However, no deleterious consequences might be observed in restored populations due to high observed heterozygosity and high gene flow. This study demonstrates that during the restoration process, genetic structures of the restored populations may be biased from the donor population. The results also highlight population genetic knowledge, especially of gene flow-limited species, in ecological restoration.     

洪水干扰对青冈种群更新的影响

本文在安徽黄山选择位于溪谷、受洪水干扰程度不同的3个样地,调查青冈种群的更新特征,结论如下：①从幼苗数量来看,受洪水影响最轻的样地3最多,密度为0.5825株m-2,洪水影响最严重的样地1数量最少,密度仅为0．1150株m-2;从幼苗性质来看,样地1萌生苗比率最高．3个样地中,随着高度级别增加,萌生苗的比例也增加。②萌生苗高度的分布接近于对称的低峰分布,实生苗的偏斜度均为正值。所有的Gini系数都较大,平均为0．5260,说明大小不等性较大。③3个样地中萌生苗均为集聚分布,样地2、3中实生苗为随机分布,而样地1由于洪水干扰较严重,实生苗多集中于地势较高的一端,呈集聚分布。以上结果表明,青冈种群的更新受洪水影响较大,溪谷种群形成了以无性繁殖为主的更新对策。     

竹叶青冈学名评注

竹叶青冈为我国南方及中南半岛常绿阔叶林常见树种,为该区域的重要材用树种。中国植物志中文版采用Cyclobalanopsis bambusifolia(Hance)Chun ex Y.C.HsuH.W.Jen作为其学名,但是基源名Quercus bambusifolia Hance由于错误鉴定1857年并未合格发表,随后基于同一模式和不同的模式,这一种加词先后多次被发表,其中涉及多个裸名、晚出同名、新名称、新组合,学名变化复杂,但其正确学名在国际权威植物分类数据库中并未采纳,正确学名在生态学等研究中亦未采用。因此,对竹叶青冈而言,其学名还存在众多疑问。为了澄清该种的学名,作者通过文献考证和标本核实查阅,对竹叶青冈学名变更历史进行追溯并根据最新的《藻类、真菌、植物国际命名法规》(简称墨尔本法规)对各变更学名进行了评述。本研究结果支持Q.neglecta(Schott.)Koidz作为竹叶青冈正确的学名。但由于国内植物学名仍以中国植物志为主要依据,而中国植物志仍采用狭义栎属Quercus s.s.的概念,为避免造成更多学名混乱,竹叶青冈的学名可沿用中国植物志英文版中学名Cyclobalanopsis neglecta,但中文版所采用C.bambusifolia为错误学名,应该弃用。     

亚热带山地突脉青冈群落能量的研究

对突脉青冈（Ｃｙｃｌｏｂａｌａｎｏｐｓｉｓｅｌｅｖａｔｉｃｏｓｔａｔａ）群落植物体各组分的热值、群落能量现存量、能量年净固定量和太阳能转化效率的研究结果表明：该群落植物体各组分样品的干重热值具有一定差异,树皮热值最高,细根热值最低。突脉青同群落的能量现存量８５２０５８ｋＪｍ－２,其中地上部分７４１４１６ｋＪｍ－２,占总量的８７．０１％;地下部分１１０６４２ｋＪｍ－２,占１２．９９％。突脉青冈１９９６年群落能量净固定量为２８２７３ｋＪｍ－２,林地太阳光有效辐射能转化效率１．３５％。     

基于青冈和滇青冈生态位模拟的湿润和半湿润常绿阔叶林替代分布及气候解释

为揭示湿润常绿阔叶林和半湿润常绿阔叶林替代分布的气候制约变量,该研究选择其代表性优势树种青冈(Cyclobalanopsis glauca)和滇青冈(C.glaucoides)为研究对象,收集两个物种的标本分布点数据和19个生物气候变量图层数据,运用MaxEnt模型,模拟其潜在分布区,通过判别分析(DFA)、方差分析(...     

百山祖北坡常绿阔叶林多脉青冈种群结构和分布格局

本研究应用理论分布模型和5个聚集强度指标,研究百山祖北坡中山常绿阔叶林多脉青冈种群分布格局。结果表明：多脉青冈种群结构呈基部和中部宽、顶部窄的形状,龄级完整,属于稳定型,但存在波动性;从整个种群和不同发育阶段来看,多脉青冈的分布格局主要呈聚集分布,且随年龄增长,聚集度逐渐降低,呈现扩散趋势,到大树期为随机分布。种群自身生物学特性、种群生境以及环境资源等综合因素影响多脉青冈的年龄结构和分布格局。     

Relationships Between Geographical Distribution of Cyclobalanopsis glauca and Climate in China

Cyclobalanopsis glauca (Thunb.) Oerst., which belongs to China-Japan subtype of East Asia district, is a evergreen broadleaved tree of Fagaceae. It is distributed widely in the subtropical region of China and also in Japan, Korea, India, Burma, etc. According to the data on geographical distribution of this species collected extensively, the indexes of vegetation-climate interaction which used widely in the world were calculated. These indexes include Kira' s water-temperature indexes, Penman's formula, Thornthwaite's indexes and climatic classification, Holdridge's life zone classification system, annual average temperature, mean temperature in January, mean temperature in July, maximum temperature, minimum temperature, ≥10 ℃ accumulated temperature and precipitation. The relationships between geographical distribution of Cyclobalanopsis glauca and climate in China has been analysed and the Kira's water-temperature indexes on the distributional upper limit, lower limit and north limit have been discussed. The relation of species versus climate in historial period and the relation of species versus climate in historial period have also been discussed according to palynological and written records. The potential change of the tree species distributional area under elevated CO2 concentration has been forecast based on Holdridge' s indexes of life zone classification system and GCM models' conclusions.     

华东地区青冈种群的遗传多样性及遗传分化

采用垂直板型聚丙烯酰胺凝胶电泳测定了华东地区6个青冈(Cyclobalanopsis glauca(Thunb.)Oerst.)种群的遗传多样性和遗传分化程度以及基因流。青冈种和种群水平都维持有较高的遗传多样性,期望杂合度分别为0.2252和0.2126,观察杂合度分别为0.1661和0.1771。种群间的遗传分化程度较低,分化度仅为5.6％,种群间的遗传一致度和遗传距离的均值分别为0.9729和0.0276。种群间的分化时间为1.4～27万年。基因流分别为4.21和20.49。