Relevant Source Area Of Pollen And Relative Pollen Productivities In Dabie Mountains

Relative pollen productivity(RPP)is a dimensionless ratio.the ratio of the number of pollen produced by vegetation per unit projected area to that of the selected reference taxa,and is the key factor for accurately interpreting the pollen assemblages in sedimentary basins.Relevant source area of pollen(RSAP)represents a certain area,where the pollen of sedimentary basins is obviously affected by vegetation coverage.Relative pollen productivity and relevant source area of pollen are necessary input parameters for Landscape reconstruction algorithm(LRA)to reconstruct regional paleovegetation coverage.Based on the detailed analysis of pollen and vegetation data of 56 sampling sites in subtropical Dabie Mountains.relative pollen productivity of 17 vegetation types were estimated by ERV model.And the relevant source area of pollen in Dabie Mountains was obtained with maximum likelihood method.The estimated results were tested by REVEALS model and LOVE model.which verified the applicability and reliability of landscape reconstruction algorithm in this area.The results are as follows:1.There are 96 pollen taxa in 56 sampling sites in Dabie Mountains.The 17 pollen types selected in this paper are:Quercus,Leguminosae,Liquidambar formosana.Plerocarya stenoptera,Artemisia,Poaceae,Platycarya strobilacea,ferns,Caslanea,Anacardiaceae,Moraceae.Cunninghamia lan.ceolata,Pinus and Aster tataricus type,representing 90.141%of the pollen and 90.867%of the vegetation in the study area.2.342 species belonging to 240 genera and 101 families were identified by field vegetation investigation.There are significant community differences in vegetation composition within 100 meters around the sampling sites in the study area.Results of principal coordinate analysis of pollen and vegetation data in different areas showed that the 0-1500 m regional vegetation data can reflect the pollen assemblages more accurately than the 0-10 m and 0-100 m vegetation data around the sampling points.3.ERV sub-model 1 produced the best goodness of fit with pollen-vegetation data in Dabie Mountains.The relevant source area of pollen in this region is 340m.4.Results of relative pollen productivity showed that in general,RPP values of trees and shrubs were higher than herbs with Quercus as the reference taxa(RPP=1).Pinus has the highest RPP,which is the dominant pollen type,followed by Liquidambar formosana,and the RPP values of other pollen taxa were lower than 1.The RPP of Artemisia is the highest in herbaceous pollen.The ferns' RPP was in the middle(0.1<RPP<1).Among all the estimated taxa.5.The results of REVEALS model and LOVE model for the reconstruction of modern vegetation in the Dabie Mountains showed that the estimation of RPPs and RSAP in this paper are reliable and can be applied to the reconstruction of regional paleovegetation.