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Copyright of Guihaia is the property of Guihaia Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shiwandashan is one of the hotspots of biodiversity in Guangxi, and its main vegetation type is mountain evergreen broad-leaved forest. In order to understand the current community status and the development status of dominant species population structure of mountain evergreen broad-leaved forests in the region, this study was conducted in a fixed monitoring sample plot of 1 hm² established within the evergreen broad-leaved forest community in the Shiwandashan. Woody plants with diameter at breast height (DBH) ≥ 1 cm in the sample plot community were used as the research objects to analyze their species compositions, diameter class structures, tree height structures, and the spatial distribution patterns of dominant species using the g(r) function. The results were as follows: (1) There were 7 517 woody plants with DBH ≥ 1 cm in the community, belonging to 52 families, 108 genera and 153 species. The dominant species in the community were Clethra delavayi, Schima argentea, Hartia villosa, Castanopsis hystrix, Engelhardtia roxburghiana, Ardisia quinquegona, Itea chinensis, Symplocos adenophylla, Eurya subintegra, Ilex pubescens, but the dominant position of dominant species was not obvious. (2) The overall average DBH of the community was 5.51 cm, and the distribution of diameter class and tree height was approximately an inverted "J" shape. The diameter class distribution of dominant species was mostly an inverted "J" or "L" shape, and the community had a large number of small and medium-sized diameter class standing trees, indicating a strong self-renewal ability of the community. (3) Dominant species coexisted stably in the community; the dominant species exhibited aggregated distribution in the sample plot, but there were differences in the location of aggregated distribution among dominant species. Overall, the community is currently in a good state of renewal, with the existence of dominant species in the top level community. However, the community has certain secondary characteristics and has not yet reached a stable top level community state. The dominant species can coexist stably and have the potential to inherit towards a stable top level community. Therefore, it is necessary to continue to strengthen management and promote the renewal and survival of the evergreen broad-leaved forest community in the Shiwandashan areas. [ABSTRACT FROM AUTHOR]

In this study, the functional traits of annual branchlets and leaves of Michelia odora, an endangered species, were sampled and measured along five different latitude gradients in Guangxi. The variation of biomass distribution and leaf functional traits along the latitude gradient were discussed. The results were as follows:(1)The total branchlet weight and total leaf weight tended to allometric growth relationship with the increase of latitude, and its biomass tended to the construction of branchlets.(2)The functional traits of the leaves showed a certain rule, i. e. increased with latitude from south to north, and its leaf area and leaf mass decrease of with the increasing latitude; leaf thickness, leaf dry matter content, stomatal length, stomatal area, stomatal density showed a trend of gradual increase; specific leaf area, leaf water content and stomatal width increased at first and then decreased, and overall showed a trend of gradual decrease, leaf tissue density decreased and then increased, which indicates that M. odora can respond to changes in the geographical environment through the plasticity of the leaf shape.(3)Specific leaf area was significantly positively correlated with leaf moisture content, but negatively correlated with leaf fresh weight, leaf dry matter content, and stomatal density. There was a significantly negative correlation between leaf dry matter content and leaf water content, which means that M. odora can respond to the change of geographical environment by adjusting and balancing the character combination of leaves.(4)CCA analysis showed that slope was the most significant variable affecting the functional traits of M. odora, the mean annual temperature also had a significant impact on the functional traits of M. odora, the mean annual precipitation, and relative humidity had a certain intensity effect on plant functional traits, but not significant. All the results are helpful to understand the adaptation characteristics of M. odora to the environment, and its response mechanism to latitude variation is of great significance. [ABSTRACT FROM AUTHOR]

Interspecific trait variation of functional traits in plants reflects the life history strategies of different species, and intraspecific trait variation reflects the responses of different individuals of the same species to different environments. The homogeneous environment of plantation is conducive to the in-depth analysis of intraspecific and interspecific variation of different trees. In this study, the intraspecific and interspecific variations of four native and precious hardwood species(Tsoongiodendron odorum, Castanopsis hystrix, Magnolia blumei, and Parashorea chinensis)in Liangfengjiang Forest plantation were studied. The results were as follows:(1) Most of the leaves of four plants of the same height had significant differences in functional traits, but only a few leaves had no significant differences in functional traits. Compared with the other three plants, the Castanopsis hystrix has lower leaf fresh weight, leaf thickness, leaf area, leaf dry weight, specific leaf area and leaf water content, but the C. hystrix has higher specific leaf weight, leaf dry matter content and leaf tissue density.(2)There were differences in leaf functional traits of the same tree species at different heights, and the differences in tree species were different. Effects of height on leaf function traits were Magnolia blumei>Parashorea chinensis>Tsoongiodendron odorum>Castanopsis hystrix. As the change of height, nine kinds of leaf tissue functional traits, leaf thickness and leaf tissue density were the most stable performance, leaf area and leaf dry weight change were bigger. Specific leaf area showed a downward trend, specific leaf weight showed an upward trend.(3)With the growth of the tree age, the leaf functional traits of Magnolia blumei changed the most, and the leaf functional traits of Castanopsis hystrix were the most stable. Effects of tree age on leaf functional traits were Magnolia blumei>Parashorea chinensis/Tsoongiodendron odorum>Castanopsis hystrix. Among the nine leaf functional traits, leaf thickness and leaf tissue density were the most affected by tree age, and leaf fresh weight, leaf dry weight and leaf area were the least affected. The leaf functional traits of the four tree species varied significantly with tree age, but did not showed obvious regularity.(4)There was no significant correlation between leaf dry matter content and leaf thickness, and there was no significant correlation between leaf water content and leaf thickness, leaf area, leaf dry weight and specific leaf weight, while there was a certain correlation between other functional traits. The above results indicate that plant functional traits have certain correlations among them, and coordinate with each other to adapt to changes in the environment. The results of this study have a certain guiding significance for the plantation of local precious hardwood species. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guihaia is the property of Guihaia Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)