| The monsoonal broad-leaved evergreen forest is an important vegetation type of the Puer area which located in the Southern Yunnan province, P.R. China. It is a land of enriched biodiversity and considered a transitional vegetation type between the tropical monsoonal rain forest and the subtropical broad-leaved evergreen forest. Due to the extensive deforestation and long-term intensive agricultural landuses, the primary forests have significantly decreased. Thus formed a spectrum of degraded ecosystem of different restoration stages. Therefore, the secondary forests that developed after the natural and artificial restoration by the destruction of primary forests in this region which has become an important forest resources. However, past ecological studies of monsoonal broad-leaves evergreen forest in Yunnan were mainly conducted in community structure, species composition, soil seed bank and biomass of the primary forests, and we still know little about those degraded vegetation after anthropogenic. In this study, field investigations were conducted in totally 25 plots (2.25hm~2) of recovery vegetation and primary forests. The recovery vegetation included different stages of natural restoration and aritficial restoration. On the basis of those field investigations, we analyzed the community composition, structure, diversity, niche, interspecific association, seed banks and the functional group and explored dynamic law of recovery strategy. The goal is to provide science reference for vegetation restoration. The main results are as follows:1.Analyze the characteristics of the monsoonal broad-leaved evergreen forest and its restoration communities, quantitaitve classification were conducted by TWINSPAN based on field investigation plots. The investigated plots were classified into 7 communities by TWINSPAN, they are primary monsoonal broad-leaved evergreen forest,community of 15 year restoration (15a), community of 30 year restoration (30a), mixed needle broad-leaved forest, needle-leaved forest and eucalyptus forest. recovery types can be divided into natural restoration and artificial restoration: natural recovery: 15a——30a——the primary forest, needle-leaved forest——mixed needle broad-leaved forest——the primary forest. Floristic composition indicated cosmopolitan percentage of restoration communities were higher than the primary forest at familiy level. Because of same species source, restoration communities were at a restoration stage form restoration communities to primary forest. Therefore, the similarity of families and genera were higher degree. the composition of species had some differences. endemic species of the primary forest communities were significantly greater than the recstoration communities. The life-form spectrum bettween restoration communites and primary forest had signicantly correlation, and natural restoration were larger than artificial restoration. Needle-leaved forest had more annuals in all communities. The percentage of microphyll of the primary forest is less than restoration communities, and leaf type did't reflect restoration degree of community.2.In the present study, the effect of restoration strategy and time on community structure and diversity were analyzed by investigating species composition, structure, and diversity of different restoration strategy and time community. The results showed that restoration strategy had no effect on species composition and diversity of family, genera, species, tree, shrub, and liana, however, restoration time had significant effect on species composition and diversity. Species richness of family, genera, species, tree, and shrub decreased at the early stage and then increased with community succession. Species richness showed an inverse J-shape with DBH increasing in all community types, while abundance showed single peak curve with DBH increasing and an inverse J-shape with height increasing. The correlation and regression analysis among restoration strategy and time and variables of community structure and diversity showed that there were significant correlation between restoration time and variables of community structure and diversity, and no significant correlation were found between restoration strategy and most of variables of community structure and diversity, which indicated that restoration time was the major factor that affects structure and diversity of community restored.3.Species-area relationships are one of the most fundamental and most studied problems in all of ecology. However, whether the species-area relationships properties, especially species-area relationships slopes, remain constant through succession time, even though the ecosystem characteristics change on seasonal to evolutionary time scales, is a controversial problem. Focusing on disturbed broad-leaved evergreen forest ecosystems, we analyzed the species-area relationships in different succession stage communities (15a, 30a, and primary forest). Investigation was performed in Pu'er, Yunnan Province. Three plots (30 m×30 m) were located in the 15a, the 30a and the primary forest respectively. Each plot was divided into 36 subplots of 5 m×5 m for the vegetation surveys. Within each subplot all stems of height (H)>1.3 m were counted, measured and identified to the species level. We also recorded environment factors such as crown density, elevation, and slop. Species richness of tree, shrub, liana and total species in the 15a, the 30a and the primary forest were calculated respectively. The species-area relationships, the accumulate rate ( Z ) and the coefficients of determination (R2) of tree, shrub, liana and total species in each succession stage community were studied. We found that the number of total species, trees, shrubs, and lianas had a highly significant correlation with the sample area in different succession stage communities, the area explained over 94% of the total variation in the number of species, trees, shrubs, and lianas. The Z of total species(0.334) and trees(0.394) were the lowest in the 30a, whereas, the Z of shrubs(0.437) and lianas(0.326) were the lowest in the 15a. No significant difference were found for the intercepts of the species-area curve of species, trees, shrubs, and lianas among different succession stage communities, however, the coefficients of determination (R2) of the species-area curve of species and lianas were the highest in the primary forest. A fitted regression line of trees and shrubs explained 99.97% of the variance of Z-value in the 15a, but there were no significant correlation between trees, shrubs, lianas, and total species richness and Z-value in the 30a and the primary forest.4.Niche and interspecific association is a focus of community dynamics. Interspecific interactions affect restoration and succession of community. Field data collection was biased on 0.81hm~2 plot (including 9 subplots) in different restoration stages (15a, 30a and primary monsoonal broad-leaved evergreen forest) which distributed in Pu'er city,Yunnan province. A series of techniques including niche breadth,niche overlap, the variance ratio (VR),chi-square test,association coefficient (AC) based on 2×2 contingency table were used to analyze change trend of tree population of different restoration stages. The results shown that:There was significant positive correlation (P<0.001) between the importance value and corresponding to niche breadth in 3 communites. 78.22% of species pairs had a niche overlap were between 0.4 and 0.8 in 15a,which indicated a strong resource utilization competition in dominant species. Simultaneously,community structure of 30a and primary forest was stability. The niche breadth increased with niche overlap,and vice versa,which reflected that the dominant species had strong competitiveness. There was a significant positive correlation in total on VR in the 15a and 30a,while the primary forest was no-significant negative association. For chi-square test,Most species pairs did not show significant association in 3 communities,which may show stronger independent distribution. The proportion of positive and negative association decreased from 15a to primary forest. There was a significant positive correlation between association coefficient and niche overlap. Generally speaking, the more niche overlap,the more association coefficient.5.Soil seed bank and seedling bank is considered an important source for natural restoration in forest ecosystems. Soil seed bank is a dynamic biotic component of plant communities that represents the population's memory in relation to selective events and seedling plays an important role for numerous tree species. Field data was based on 0.72hm~2 plot (including 8 subplots) in different restoration stages (15a, 30a) and primary monsoon broad-leaved evergreen forest which distribute in Caiyanghe nature reserve, Yixiang township and Xinfang reservoir, Puer city, Yunnan, China. Germination experiments carried out in the greenhouse, which lasted 7 months. On the basis of analyzing soil seed bank and seedling bank density and its relation to the above-ground vegetation. The results were summarized as follows: 2645 seeds germinated in all soil samples, 83 species in72 genera and 37 families were recorded. Total seed density of 30a (424±91.53 seeds/m~2) was significantly higher than primary forest (148±23 seeds/m~2). There was no significant difference between 15a (362.33±77.05 seeds/m~2) and other two types. Seed density of 0-2cm and 5-10cm layer was significantly higer than 2-5cm layer in pirmary forest, while no significant difference among 3 layers in 15a and 30a. Compositae was most abundant species in three community types,because of their wind dispersal way. Shannon-Wiener index of 30a was signifcantly higher than 15a and primary forest, but species richness was not significant difference in three types (including three layer). The seed density of herb was significantly higher than other life form in 3 community types. Seed density of perennial herb of 30a was significantly higher than 15a and primary and seed density of annual herb of 15a was signicantly higer than 30a and primary.and seed density of herb plant and fern plant of 30a was significantly higer than the primary forest. Dicranopteris pedata was most abundant species in restoration stages, especially in 30a. Annual herb offen emerged in early stages of restoration, such as Lindernia nummularifolia, which had short distance to tea park and farm land and had richness seed source. Castanopsis echidnocarpa is dominat species of monsoon broad-leaved evergreen forest, which was most abundant seedling of 30a and primary. Castanopsis calathiformis was most abundant seedling species of 15a. Tree seedlings were more than shrub seedlings. Tree seedling was main composition in all seedling bank, because of survival strategy of seed. Seedling bank density of primary was significantly higher than 15a, which had signifant negative correlation with soil seed bank density (P<0.05)and stand density(P<0.01), had signifantly positive correlation with soil bulk desity and Ph (P<0.05). The similarity coefficient (from 0.0375 to 0.1538) between soil seed bank and above-ground vegetation was generally low in three community types. Similarity coefficient between soil seed bank and herb was higher than soil seed bank and tree layer. Seedling bank was more similar with tree layer than soil seed bank, so forest restoration of monsoon broad-leaved evergreen forest mainly relyed on seed rain of tree layer.6.Liana is important component of forest ecosystem, which usually affects restoration and succession of the communities. Relationship between liana and host tree has significant implications for forest conservation and sustainable management. Field data collection was based on 0.81hm~2 plot (including 9 subplots) in different restoration stages (15a, 30a and primary monsoonal broad-leaved evergreen forest distribute in Caiyanghe nature reserve, Yixiang Township and Xinfang reservoir, Pu'er city, Yunnan, China. On the basis of analyzing liana species richness, density, abundance, size structure, diversity indices and the climbing mechanism in the different restoration period, the relationship between liana and host tree was discussed. The results shown that: 1292 climbing lianas (DBH≥0.1cm), belonging to 64 species in 51 genera and 34 families were recorded in all plots. The liana richness,density(DBH<0.1cm), basal area at breast height and mean basal area at breast height in primary forest were significantly higher than restoration stages. There was no significant difference of density (DBH≥1cm), average DBH and average length between primary forest and 15a, though both were significantly higher than that of 30a. Species composition and DBH class distribution of lianas varied significantly in the three community types. Mucuna macrocarpa,Celastrus monospermus and Gnetum montanum are most abundant species. These species were found in all restoration stages and primary forest.Mucuna macrocarpa is an early successional species which needs intensive light environment and Gnetum montanum is a late successional species. Species-area curve showed that primary forest had higher species richness than 15a and 30a, which confirmed that primary forest played an important role in biodiversity conservation of lianas. Liana abundance decreased significantly while its DBH class increased. DBH of more than 95% lianas was less than 5cm. The lianas of large diameter class (DBH≥10cm) were found only in primary forest and 30a. One liana per host tree was most abundant in three community types. Host trees were more likely to be infested by lianas when their DBH was larger than 15cm in primary forest and liana-host tree relationship showed different trends in restoration stages. Large tree was more susceptible to be climbed by liana. There was a significant positive correlation (P<0.001) between the liana DBH and host tree DBH. DBH of liana increased with the growth of DBH of host tree in primary and 15a. Stem twining caused more mechanical damage in 4 climbing ways, and the damage for primary forest were significantly lower than that for restoration stages. Density of tendril climber showed that primary forest was undergoing a dynamic process. Species composition and abundance change of root climber and hook climber can be used as an indicator to reflect restoration level of monsoonal broad-leaved evergreen forest of post-disturbance. Primary forest had more Piper flaviflorum than 15a and 30a and Fissistigma acuminatissimum did not appeare in the restoration stages. Deforestation is main factor that affects liana species composition and distribution and reduces lianas abundance and richness significantly. Restoration time has an important effect on regeneration of lianas.7.Vascular epiphytes are important components of species richness in monsoonal broad-leaved evergreen forest. Field data collection vascular epiphytes was based on 0.81hm~2 plot (including 9 subplots) in different restoration stages (15a, 30a and primary monsoonal broad-leaved evergreen forest distribute in Caiyanghe nature reserve, Yixiang Township and Xinfang reservoir, Pu'er city, Yunnan, China. On the basis of analyzing vascular epiphytes species richness, abundance, distribution, similarity coefficient, the relationship between epiphytes and phorophytes was discussed. The results shown that: (1) 3116 vascular epiphytes, belonging to 22 species in 20 genera and 9 families were recorded in all plots. (2) Diversity of vascular epiphytes was lower in restoration stages (15a, 5 spp. And 30a, 7 spp.) compared to primary forest (17 spp.). (3) Epiphytes species composition in primary forest and restoration stages differed markedly: community of 15a restoration harboured no orchid species but more fern species and primary forest hold more orchid species. Probably the families occurring only in primary forest sites of our study may be useful as bioindicators to determine the degree of restoration in monsoonal broad-leaved evergreen forest. (4) Epiphytes abundance were also lower in restoration stages. The decrease in species numbers and abundance as well as the differences in species composition was mainly due to the less diverse phorophyte structure and less differentiated microclimate in the disturbed and secondary vegetation compared to the primary forest. S?rensen coefficient between 15a and primary forest was higher than between 30a and primary forest. (5) The vascular epiphytes were clumped horizontally in 3 community types. Vertically, vascular epiphytes of 15a were mainly distributed at 0～5m and primary forest was up to 20m. (6) Vascular epiphytes species richness and abundance were both significantly positively correlated with host tree size but restoration stages didn't have.
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