Font Size: a A A

Species Composition And Geographical Differentiation Of The Fagaceae Community In Subtropical Evergreen Broad-leaved Forest In China

Posted on:2020-05-15Degree:MasterType:Thesis
Country:ChinaCandidate:H LiFull Text:PDF
GTID:2370330578463267Subject:Forest cultivation
Abstract/Summary:PDF Full Text Request
The subtropical evergreen broad-leaved forest has many rich and diverse community types and a wide distribution area.It is the most representative type of forest vegetation in the subtropical region of China.The Fagaceae community is a dominant group of subtropical evergreen broad-leaved forests with very high species diversity and plays an important role in the ecological stability of evergreen broad-leaved forests.Due to the driving of regional differentiation,the biodiversity of the Fagaceae community is geographically different.At present,most of the research on the Fagaceae community is concentrated on a small scale,and there are certain limitations.In order to clarify the species composition and geographical differentiation of Fagaceae communities,the Fagaceae communities in China subtropical evergreen broad-leaved forest are studied as a whole.Based on the collected community characteristics and spatial information,combined with spatial analysis,similarity analysis and correlation analysis to determine the species richness,species diversity and geographical distribution characteristics of the main group of Fagaceae community.Redundancy analysis and variance decomposition and correlation analysis are used to determine the main environmental factors that affect this feature.The main conclusions are as follows:(1)The subfamily of the subtropical evergreen broad-leaved forest in China consists of five groups,Castanopsis group of formation,Cyclobalanopsis group of formation,Lithocarpus group of formation,Castanopsis and Schima group of formation,Castanopsis and Cryptocarya group of formation.The Castanopsis group of formation accounts for 66.31%of the total community and 24.31%of the Cyclobalanopsis group of formation.The other group types appear in the community of the Evergreen broad-leaved forest,and the frequency of the community is 9.38%.(2)The geographical distribution of the Fagaceae community has latitudinal zonality.The number of group types generally increases from north to south.Yunnan,Guangxi,Fujian and Taiwan are the regions with the highest number of groups.The spatial distribution of Castanopsis group of formation and Cyclobalanopsis group of formation in the five groups are similar,and the similarity coefficient is 0.897.Castanopsis group of formation ranges from 21° to 31°N,99° to 121°E,and Cyclobalanopsis group of formation ranges from 220 to 32°N and 101° to 121°E,extending throughout the evergreen broad-leaved forest area.The spatial distribution of Castanopsis and Schima group of formation,Castanopsis and Cryptocarya group of formation are also similar,and the similarity coefficient is 0.75.Geographical distribution is narrow,mainly distribute in Guangdong,Guangxi,Fujian,Yunnan and Taiwan.The spatial distribution of the Lithocarpus group of formation is lower than that of other groups,and the geographical distribution is discontinuous,mainly distribute in Hunan,Yunnan and Taiwan.(3)The Fagaceae community has a vertical zonal distribution in the elevation distribution,and the number of groups is increasing from a high altitude gradient to a low altitude gradient.The elevation range of the community is between 0 and 3000 meters,of which 0 to 1500 meters is the main distribution belt of the Fagaceae community.The Castanopsis group of formation distribution range of conical forests is consistent with the overall distribution range of the Fagaceae community,and the distribution ranges is wide.The distribution of Cyclobalanopsis group of formation ranges from 0 to 2500 meters.Castanopsis and Schima group of formation distribution range from 0 to 2000 meters.Castanopsis and Cryptocarya group of formation distribution range from 0 to 1000 meters.The distribution of Lithocarpus group of formation is discontinuous and distributes at low and high altitude.(4)The highest species richness in the arbor layer of the Fagaceae community is the Castanopsis and Cryptocarya group of formation,with a value of(4.30±0.74);The highest species richness in the shrub layer is the Castanopsis group of formation,with a value of(3.67±0.12);The highest species richness in the herb layer is the Lithocarpus group of formation,with a value of(2.98±0.40).(5)The species diversity of the Fagaceae community generally shows shrub layer>arbor layer>herb layer.There were significant differences in the diversity indices of the five groups.Among them,the Shannon-Wiener index of the Castanopsis and Cryptocarya group of formation is the highest,and the values of trees,shrubs and herb layers is(2.94±0.26),(3.20±0.11)and(2.68±0.21).The Simpson index is the highest in the tree layer and shrub layer of the Lithocarpus group of formation,it is(0.86±0.02)and(0.944±0.01).The Simpson index of the Castanopsis and Schima group of formation herb layer is the highest,It is(0.75±0.04);The pea layer and shrub layer of the Castanopsis and Cryptocarya group of formation shell Guilin have the highest Pielou index,It is(0.90±0.02)and(0.94±0.001).The Castanopsis and Schima group of formation herb layers have the highest Pielou index.It is(0.87±0.01).(6)The correlation analysis of species diversity and environmental factors shows that:LA and temperature(AMT,MTCM,TAR,MTCQ)are the most important environmental factors affecting the species diversity of the arbor layer in the Fagaceae community.LO and temperature(AMT,MTCM,TAR,MTCQ)are the main environmental factors affecting shrub layer species diversity.The species diversity of herbaceous layer is mainly affected by temperature(ISO,TS and TAR)and precipitation APRE,PREWM and PRES).(7)The relationship between environmental factors and species composition of different groups shows that:The key environmental factors that affect the species composition of tree layer are LO,LA and TAR;The key environmental factors affecting the species composition of the shrub layer are LO and soil pH value.The species composition of herbaceous layer is mainly affected by the PREDM,soil pH,LA and PRES.(8)The relationship between plant community distribution and environmental factors such as ALT,LA,MDR,MTWAQ and TS are significant.
Keywords/Search Tags:Group of formation, Geographical distribution, Species richness, Species diversity, Environmental Factors, Fagaceae, Evergreen broad-leaved forest
PDF Full Text Request
Related items