密度调控对马尾松人工林生态系统碳储量的影响

采用密度调控对贵州台江县12年生马尾松人工林碳储量进行研究。结果表明，密度调控提高了马尾松人工林乔木层、林下植被和凋落物层碳的累积，高密度(H)（1 800株·hm^-2）、中密度(M)（1 566株·hm^-2）和低密度(L)（1 350株·hm^-2）及CK（未间伐:2 016株·hm^-2）密度下马尾松人工林各组分碳储量乔木层＞土壤层＞林下植被层＞凋落物层。乔木层碳储量分别高出CK2.58、5.69 t·hm^-2和1.38 t·hm^-2；土壤层分别高出CK3.50、4.95 t·hm^-2和-13.43 t·hm^-2；林下植被层分别高于CK1.88、2.59 t·hm^-2和4.14 t·hm^-2，凋落物层分别高于CK0.14、0.27 t·hm^-2和0.36 t·hm^-2，林下植被和凋落物层碳储量较CK达显著差异（p＜0.05）；H和M密度下生态系统总碳储量分别较CK提高8.1 t·hm^-2和13.49 t·hm^-2，L密度低于CK7.54 t·hm^-2，马尾松人工林生态系统总碳储量以M密度调控最大，故马尾松中龄人工林林分经营过程中以M密度经营较好。

Effects of Density Regulation on Carbon Storage of Pinus massoniana Plantation Ecosystem

An investigation of the effects of density regulation on carbon deposits was conducted on a 12-year-old Pinus massoniana plantation located in Taijiang County of Guizhou Province.Besides the control (CK,without regulated,2 610 plant·hm^-2),three densities were set up: high (H,1 800 plant·hm^-2),medium (M,1 566 plant·hm^-2),and low (L,1 350 plant·hm^-2).The results showed that density regulation helped improving the carbon accumulation in the tree layer，understory vegetation and litter layer.The amounts of carbon storage was in the order of tree layer＞soil layer > litter layer > undergrowth layer under all densities.The carbon storages in tree layers with high,medium and low densities were 2.58,5.69， and 1.38 t·hm^-2 higher than that of the control; in soil layer,3.50,4.95,and 13.43 t·hm^-2 higher,in litter layer,1.88,2.59,and 4.14 t·hm^-2 higher; and in undergrowth layer,0.14,0.27,and 0.36 t·hm^-2 higher.The carbon storages of understory vegetation and undergrowth layer were significantly different compared with CK（p＜0.05）.The total carbon storages of the ecosystem with H and M densities were 8.1 t·hm^-2 and 13.49 t·hm^-2 higher than the CK ,and with L density,7.54 t·hm^-2 less than the CK.It was concluded that the total carbon storage of P.massoniana plantation ecosystem with M density was the highest,indicating that M density should be adopted in the management of middle-age P.massoniana plantation.