| Castanopsis carlesii community is unique and relatively stable climax community in subtropical regions.However,the distribution range and the productivity of the Castanopsis carlesii forest have been continuously decreasing with the exportation by human being in half a century,and the resource of the forest is at the edge of exhausting.This paper studied on Castanopsis carlesii community in iingshi moutain Fuqing of Fujian province,where we choose five piece of sample plots(P1:not cutting sample plot;P2,P3:selective cutting sample plot in 1960;P4:clear cutting sample plots in1970;P5:clear cutting sample plots in1960)with different style of cutting and recovery time.The data was received through investigating the sample plot. The Castanopsis carlesii population of five sample plots were analyzed and compared by using importance value,size structure,spatial distribution pattern,βdiversity,species abundance distribution,life process of the Castanopsis carlesii population,as well as analyzed and compared on the niche characteristics of the main populations in five sample plots,Studing the ecological response and probbing into the law of variations of the Castanopsis carlesii population with different style of cutting and recovery time.The objective of our study is to master the variations law of forest after cutting and provide a theoretical basis for the restoration of subtropical Castanopsis carlesii community and the scientific evaluation of National forest park conservation district.The results indicated as follows:1)The results of LSD of importance values among the main tree species in different human-caused disturbance community were as follows:the importance values between Castanopsis carlesii and other main tree species in P1,P2 and P3 sample plot indicate significant difference at 0.01 level,it signified that Castanopsis carlesii population in P1,P2and P3 sample plot had significant predominance.The importance value between Castanopsis carlesii and Pinus massoniana or Castanopsis carlesi and Cunninghamia lanceolata in P4 sample plot indicate significant difference at 0.01level.The importance values between Castanopsis carlesii and Castanopsis carlesii in P5 indicate not significant difference at 0.05level.2)Seen from the size structure of Castanopsis carlesii in different human-caused disturbance community,the Castanopsis carlesii population in P1,P2,P3 and P5 sample plot could be attributed to growing population with a typical reversed J-shaped size structure,while the Castanopsis carlesii population in P1 did not show a typical reversed J-shaped size structure.The Castanopsis carlesii population in P4 was still a growing population because it owns more seeding and sapling.3)Seen from spatial distribution pattern of Castanopsis carlesii population,the patters of Castanopsis carlesii population in P1～P5 all were clumped.The patterns of class size of Castanopsis carlesii population showed the rule that the seeding and sapling classes were clumped but the middle or the big tree classes were random.It was found that the patterns of Castanopsis carlesii population changed with the time during their development period,the clumped intensity of Castanopsis carlesii population was gradually reduced from the seeding or sapling to big tree,and the populations were diffusing4)We can draw conclusion by applyingβdiversity index combined with LSD,the result as follow:There would be much similar species composition and less habitat difference as long as there were the same dominant species in community,similarly,there would be much similar species composition and less habitat difference as long as there were the same cutting disturbance in sample plot.Dominant species together with cutting disturbance impact on community, determining species composition and habitat difference.5)Species-abundance distribution models in P1～P5community were studied by using patterns of log series distribution,log normal distribution,broken stick model to evaluate the simulation of such methods.The simulation results show that the species-abundance distribution of tree layer,shrub layer and community can be well described by the log normal distribution model but broken stick distribution model.The tree layer,shrub layer and community can be well described by log series distribution model expect the community of P5.And the curve forms of danger scale function and mortality function of Castanopsis carlesii in different human disturbance were coincident.6)In the paper,the 10 main tree populations in different cutting disturbance communities have been analyzed by using the niche breadth,niche overlap,and niche proportional similarity. The result indicated that the Castanopsis carlesii population of P2and P3have much higher niche breadth than P1,and the Castanopsis carlesii population of P4and P5 have higher niche breadth than P2and P3.It signified that cutting disturbance can improve the niche breadth of Castanopsis carlesii population,and clear cutting has stronger influence than select cutting on adaptability to environment.Niche overlap between Castanopsis carlesii and other populations was the highest in clear cutting sample plot,select cutting decreased from cutting,and not cutting was lowest.7)time-specific life table of different human disturbance Castanopsis carlesii population was established on diameter class,which revealed that seeding were abundant relatively.The survival curve of P1,P2,P3 belonged to the typical of Deevey-Ⅲ,while the survival curve of P4,P5 belonged to the typical of Deevey-Ⅱ;In the process of development of population,there were three death peaks in P1.One death peaks in P2and P3,and there will be a second death peak come up with succession proceeding.There were two death peaks in P5.Survivability of the Castanopsis carlesii population in different sample plots dropped down monotonously,and accumulative mortality rose up correspondently with increasing of the age class,and varying extent was large in the earliness and small in the late stage.
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