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江西省九连山常绿阔叶林空间格局与动态研究

Research on Distribution Pattern and Vegetation Dynamics of the Evergreen Broad-leaved Forest in Mount Jiulianshan of Jiangxi Province

【作者】 简敏菲

【导师】 刘琪璟;

【作者基本信息】 南昌大学 , 环境工程, 2008, 博士

【摘要】 本研究以九连山国家级自然保护区常绿阔叶林为研究对象,在植物区系地理学、植物群落生态学与种群生态学的基础上,综合应用数量生态学、生态位理论、生物统计学与计算机技术对九连山常绿阔叶林群落的植物区系、群落结构特征、空间分布特征、种间联结性及物种多样性、种群生态位、群落数量分类及群落动态特征进行研究。得到以下主要研究结果:(1)九连山常绿阔叶林群落与植被类型丰富,植物区系复杂,具有明显的过渡性质;植物区系起源古老,保存有大量第四纪冰期前的区系成分;珍稀濒危植物丰富。各群落主要由热带、亚热带科属组成,优势科为壳斗科(Fagaceae)、樟科(Lauraceae)、山茶科(Camelliaceae)、安息香科(Styracaceae)、杜鹃花科(Ericaceae)、木兰科(Magnoliaceae)等科,优势树种以相应的优势科属树种为主。(2)物种数量特征采用重要值进行分析,群落乔木层较高大,垂直分化较明显;树种水平分布不均。许多常绿阔叶林群落正处于过老或更新发展状态中,并常见有阳性落叶树如枫香(Liquidambar formosana)、拟赤杨(Alniphyllumfortunei)、光皮桦(Betula luminifera)等侵入林窗,形成常绿与落叶阔叶树混交林。采用“空间序列代替时间变化”的方法研究群落种群的年龄结构,结果表明,群落种群的年龄结构既有稳定增长型,又有稳定型趋向衰退波动的类型。(3)应用聚集度指标、方差和均值比率、负二项式分布等方法研究各群落物种及优势种群的分布格局,结果表明:构成群落乔木层的28个优势种群的分布格局均属集群分布,并符合负二项式分布。种群分布格局的动态变化规律表现为从幼苗→幼树→中树→大树的时间序列上,各种群的分布格局趋势是从集群分布→随机分布。(4)采用主成分排序方法与聚类分析方法对各群落进行排序与分类,各种方法的分析结果存在一定的差异,但总体上表现出一致性。排序与聚类分析的结果均表明,九连山自然保护区18个常绿阔叶林群落可划分为甜槠(Castanopsiseyrei)与木荷(Schima superba)群系,南岭栲(Castanopsis fordii)、丝栗栲(Castanopsis fargesii)、米槠(Castanopsis carlesii)、罗浮栲(Castanopsis fabric)等栲属群系,深山含笑(Manglietia maudiae)群系,南方红豆杉(Taxus mairei)群系、枫香与拟赤杨群系,观光木(Tsoongiodendron odorum)群系,猴头杜鹃(Rhododendronsimiarum)等7个群系。(5)采用α多样性和β多样性等不同测度指标研究群落的物种多样性和群落动态关系,结果表明:各群落不同层次的α多样性主要测度指标由大到小的变化规律为灌木层>乔木层>草本层,符合亚热带森林生态系统的一般规律。β多样性反映了不同群落间物种组成的差异,不同β多样性指标测度结果综合分析表明:低、高海拔的物种多样性较中海拔低,物种随海拔梯度变化呈现“中间高度膨胀”现象;物种变化速率较大值总是出现在受外界干扰及生境较严峻的低高海拔。(6)用总体相关性检验(方差比率法)分析乔木层28个主要树种和灌木层31个主要种群间的总体联结性,并通过x~2检验和及其它不同指数方法检验各种对间的联结性,采用Pearson相关系数和Spearman秩相关系数检验种间协变的关系。结果表明:乔木层建群种及灌木层优势种群的整体联结性均为显著的正联结。乔木层、灌木层各层优势种对间的联结性较松散,正联结的种对少于负联结的种对,乔木层28个优势种群可划分为喜阳和耐荫两类典型的不同生态种组。(7)采用Levins生态位宽度公式、Shannon-Wiener指数和Hurlburt指数测定各优势种群的生态位宽度,各指数测定结果一致表明:生态位宽度最大的分别为柃木(Eurya japonica)、润楠(Machilus microcarpa)、木荷、罗浮栲等种群,体现了以上种群均具有广泛的生态适应性。Petraitis普遍重叠指数结果表明,九连山常绿阔叶林群落中28个优势种群并不存在完全普遍重叠,主要与它们对水分和光照等不同环境因子的适应性有关。MacArthur生态位重叠指数结果清楚地表明了本研究不同群落中资源的不同利用状况和物种配置情况,一般表现出:生态位宽度接近的物种之间有较大的生态位重叠,生态习性相似的物种之间也有较大的生态位重叠。

【Abstract】 This paper is a report about studies on floristic analysis, community structural features, distribution pattern, inter-specific association and niche of the major species, biodiversity, numerical classification, and dynamics of the evergreen broad -leaved forest in Jiulianshan National Nature Reserve of Jiangxi Province. The research is based on the theory and methods in floristic geography, community ecology, population ecology, mathematics ecology, plant ecological niche theory, biological statistics and computer technology. The main obtained results are as follows:The community of the evergreen broad-leaved forest is typical in the subtropical forest of South China, with an evergreen physiognomy. The flora is rich with transitional features, the flora had come floristic constituent before Quaternary and retains many floristic elements before Quaternary, and there were many rare and endangered plants in the community. The forest communities consist mainly of tropical and subtropical families and genera. Dominant families were mainly Fagaceae, Lauraceae, Theaceae, Styracaceae, Ericaceae, Magnolicceae, and etc., which were also dominant taxa.The quantity characteristics of plant species were analyzed and evaluated based on importance value. The forest communities were relatively lofty with significant, and their horizontal distribution was heterogeneity. The vegetation was a combination of natural forest, secondary natural forest and silvicultural rehabilitation. Some evergreen broad-leaved communities were matured or being renovated. Various hardwood trees were also encountered with high frequency, such as Liquidambar formosana, Alniphyllum fortunei, Betula luminifera etc.. These species with numerous individuals recruited into canopy gaps and forming evergreen and hardwood broad-leaved forests. The age structure and developments of dominant population were analyzed by the method of space for time sere. The results were as follows: the age structure of some population was stable or increasing, and that of the rest was moving from being stable to being declining.The spatial distribution pattern of the main 28 dominant trees was studied by using aggregate indices, variance ratio and the Possion distribution methods. The results showed that the spatial distribution pattern of the 28 dominant trees in the forest were all aggregated pattern in population and they were the Possion distribution of all the plots. The distribution pattern of the dominant species in the different communities was from clump to random in time serial from seedling to trees.The method of principal components analysis and the different methods of hierarchical cluster analysis included the nearest neighbor method , furthest neighbor method, within-groups linkage and between-groups linkage method were used to carry out numerical analysis for the community of the evergreen broad-leaved forest in Jiulianshan National Nature Reserve. The results indicated that there were a few differences among different methods, but the different classification results were consistent on the whole. The 18 forest plots were divided into 7 formations according to the important values of species in canopy layer, they were Castanopsis eyrei and Schima superba formation, Castanopsis fordii、Castanopsis fargesii、Castanopsis carlesii and Castanopsis fabric formation, Manglietia maudiae formation, Taxus mairei formation、Liquidambar formosana and Alniphyllum fortunei formation, Tsoongiodendron odorum formation and Rhododendron simiarum formation。The relationship between biodiversity and dynamics of different communities were analyzed by with different indices ofα-diversity andβ-diversity. The results showed that mostα-diversity indices in different layers of different communities were different from each other. The indices of tree layer was usually lower than that of shrub layer, and was bigger than that of herb layer, which was consistent with the general pattern in subtropical forest ecosystem in South China. According to the results of different indices ofβ-diversity, the species of the evergreen broad-leaved forest in low and high elevations were fewer than those in the middle elevation; species diversity appeared "mid-altitude bulge" and the highest species turn over rate was constantly appeared in the low elevation where was disturbed by human activity, and in high altitudes it was due to harsh conditions.The overall relatedness and inter-specific association of the main 28 tree layer species and 31 shrub layer species of the evergreen broad-leaved forest were examined by using variance ratio (VR) , x~2 test and different indices methods for 2×2 contingency table, Pearson correlation coefficient test and Spearman rank coefficient test. The results showed that the inter-specific association of the tree layer or the shrub layer species were significantly positive on the whole, but there were fewer paired species of positive association than those of negative association. According to the adaptability to the environment and the relationships between plants and environment, the main 28 canopy layer species were divided into two different ecological species groups, i. e., shade-intolerant and shade-tolerant.The niche breadths of 28 dominant species in the tree layer were investigated by using Levins index, Shannon-Wiener index and Hurlburt index. The results of different indices showed consistency and indicated that the niche breadths of Eurya japonica, Machilus microcarpa, Schima superba, Castanopsis fabric were larger than that of others because these species had strong adaptability. Based on the results of Petraitis’s General Overlapping methods, there was not absolutely general overlapping among all species in the communities, and the reason was resulted from the differences among them for adapting to moisture and light. The niche overlap between dominant species in these 18 communities were calculated with Mac Arthur methods. The results showed their differences in resource utilization and species composition clearly. Generally, species with similar ecological features niche breadth tended to have greater niche overlap. But great niche overlap didn’t necessarily lead to competition if their life forms were different, on the contrary, the relationships between them were very likely to be reciprocal.

  • 【网络出版投稿人】 南昌大学
  • 【网络出版年期】2008年 11期
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