关键词: 森林群落, 次生演替, 种间协变

Abstract: From June 2006 to May 2007, the monthly CO₂, CH₄, and N₂O concentrations in soil profiles in central Guizhou Karst area were measured, with their spatiotemporal correlations analyzed. The CO₂ and N₂O concentrations in the soil profiles were 0.35-35.3 ml·L^-1 and 0.31-5.31 μl·L^-1, respectively, being higher in summer and autumn than in winter and spring, and the CH₄ concentration was 0.1-4.7 μl·L^-1, with no significant difference among seasons. With the increase of soil depth, the CO₂ and N₂O concentrations increased first and then decreased or tended to be stable, while CH₄ had an inverse trend unlike CO₂ and N₂O. The spatiotemporal distribution of CO₂ in the soil profiles was significantly positively correlated with that of N₂O, but negatively correlated with that of CH₄; while the spatiotemporal variations of CH₄ and N₂O were negatively correlated, being significant in Huaxi grassland, Qingzhen hardwood forest, and forest park Pinus massoniana forest and hardwood forest.

Key words: Forest communities, Secondary succession, Interspecies covariation