昆明北郊水源保护区圣诞树人工林分生物量及生产力的研究

STUDIES IN BIOMASS AND PRODUCTIVITY OF ACACIA DEALBATA PLANTATION IN THE PROTECTED DISTRICT OF WATER SOURCES IN NORTH KUNMING

昆明北郊松华坝水源保护区１０年生圣诞树人工林分生物量为１３７．９２６ｔ／ｈｍ２，净生产量为２４．１２８ｔ／ｈｍ２·ａ，其中乔木层生物量为１３０．４１８ｔ／ｈｍ２，净生产量为１９．３６９ｔ／ｈｍ２·ａ，下木和草本植物生物量和净生产量分别为０．９３５ｔ／ｈｍ２和０．６０９ｔ／ｈｍ２·ａ，枯枝落叶层现存量和林分凋落物量分别为６．５７３ｔ／ｈｍ２和４．１５０ｔ／ｈｍ２·ａ。在林分产量结构方面，１０ｍ以下树干生物量占其总量的９８．３７％，４～１２ｍ之间枝、叶生物量分别占整个枝、叶生物量的８５．５１％和９４．９０％，地下根系在离地面２０ｃｍ深土层内的生物量占总根量的７３．０４％。目前，该类林分群落结构不合理，整体效应较差，保持水土作用未能充分发挥出来。应及时进行间伐，调整群落产量结构；注重对林下地被植物及枯枝落叶层的保护，以提高其综合效益。

in this paper, the biomass and productivity of 10 year old Acacia dealbata plantation at an altitude of 1960 m in the protected ditrict of water sources at Songhuaba in north Kunming are studied. The results show that the estimated biomass of A.dealbata plantation is 137. 926 t/hm2,the productivity is 24. 128 t/ hm2. a. The total biomass of tree layer is 130.418t/hm2 in which the percentage of trunks, branches, leaves and roots are 54. 917%, 16. 60%, 9. 17% and 19.32%respectively, and the productivity is 19. 369 t/ hm2. a. The biomass and productivity of undergrowth and herb layer are 0. 935t/hm2 and 0.609t/hm2. a respectivily. The standing crop of litter and annual litter-fall are 6.573t/hm2 and 4. 150 t/hm2. a respectively. Regarding the production structure, the biomass of trunks under the height of 10m account to 98.37% of the total, the biomass of branches and leaves between 4m and 12m account to 85. 1% and 94.90% of the total respectively, and the biomass of roots below the ground level of 20cm account to 73. 1%.The present stage structure of the community is irrational, and the effect of soil and water conservation of the plantation is not fully displayed according to the anlysis of distribution structure of the biomass in the community. Finally, the author suggests that timely tending felling in the plantation should be conducted, and also attention should be paid to protection of cover plants and litter so as to regulate the structure of production and improve the integrate effect of the community.