Study on the Biomass and Soil Fertility of Pure and Mixed Stands of Cunninghamia lanceolata,Liriodendron chinense and Sassafras tsumu

From the viewpoints of tree growth,biomass,spatial distribution pattern and soil fertility,the pure and mixed stands of 5 year old Cunninghamia lanceolata and Liriodendron chinense and Sassafras tsumu grown in Shaowu of Fujian Province were studied.The results showed that the C.lanceolata L.chinense,C. lanceolata S.tsumu mixed stands and the pure stands of L.chinense,and S.tsumu have higher productivity.The biomass of pure L.chinense stand was 91.933 t·hm-2,and the mixed stand(C.lanceolata∶L.chinense=2∶1)was 45.32 t·hm-2,which are 4.55 times and 2.24 times that of pure C.lanceolata stand.The biomass of mixed stands of C.lanceolata and L.chinense in the ratio of 3∶1 and 5∶1 were 36.1201 t·hm-2and 34.2920 t·hm-2respectively,which were 78.96% and 69 90% higher than that of pure C.lanceolata pure stand.The biomass of pure S.tsumu stand was 60.105 t·hm-2,which was 3.31 times that of the C.lanceolata Pure stand.The biomass of mixed stands of C.lanceolata and S. tsumu in the ratio of 2∶1,3∶1 and 5∶1 were 32.426 t·hm-2,28.635 t·hm-2and 25.822 t·hm-2,which were 78.54%,57.67% and 41 18% higher than that of the C.lanceolata pure stand.The mixed stand of C.lanceolata with L.chinense and S.tsumu could form better stand structure as well as benefits the soil fertility and promotes the growth of C.lanceolata.The authors hold that the mixture pattern of C.lanceolata and L.chinense in the ratio of 2∶1 is a good afforestation pattern and worth to be extenuated.