Our ability to estimate the changes in carbon (C) pools and fluxes due to forest conversion is hampered by a lack of comparative studies. We measured above- and belowground C pools and soil respiration flux at four forested and four pasture sites in the southern Appalachian Mountains. Above- and belowground C pools were significantly larger (P < 0.01, t-test) at forested sites relative to pasture sites. The largest differences were in aboveground live biomass, which averaged 152 Mg ha−1 C at the forested sites and 1.9 Mg ha−1 at the pasture sites. Coarse root and stump C and surface detritus were also substantially different, averaging 41.3 and 32.6 Mg ha−1 C, respectively, at the forested sites, and less than 1 Mg ha−1 at the pasture sites. Fine root C was higher and mineral soil C lower at pasture sites relative to comparable forested sites, but neither difference was statistically significant. Soil respiration at a given temperature was generally lower at pasture sites relative to forest sites. However, soil temperatures at pastures were consistently higher than at forest sites. Estimated annual soil respiration flux averaged 10.9 Mg C ha−1 at the pasture sites and 12.6 Mg C ha−1 at the forested sites. FOR. SCI. 51(4):372–383.

中文翻译：

---

南阿巴拉契亚山脉的森林和牧场碳库和土壤呼吸

由于缺乏比较研究，我们估计由于森林转变造成的碳（C）库和通量变化的能力受到限制。我们测量了阿巴拉契亚山脉南部四个森林和四个牧场的地上和地下碳库和土壤呼吸通量。相对于牧场，森林地区的地上和地下碳库显着更大（P < 0.01，t 检验）。最大的差异在于地上活生物量，森林地区平均为 152 Mg ha−1 C，牧场地区为 1.9 Mg ha−1 C。粗根和树桩 C 以及表面碎屑也有很大差异，森林地区平均分别为 41.3 和 32.6 Mg ha−1 C，牧场地区低于 1 Mg ha−1。与可比较的森林地区相比，牧场地区的细根碳含量较高，而矿质土壤碳含量较低，但这两种差异均无统计学意义。相对于森林地点，牧场地点在给定温度下的土壤呼吸通常较低。然而，牧场的土壤温度始终高于森林地区。估计牧场的年土壤呼吸通量平均为 10.9 Mg C ha−1，森林地区的年土壤呼吸通量平均为 12.6 Mg C ha−1。为了。 SCI。 51（4）：372-383。