关键词: 碳足迹, 小麦-玉米种植体系, 小麦-夏花生种植体系, 温室气体排放

Abstract: In this paper, 16 typical plots of four successional communities were investigated by using the method of spatial sequence instead of time successional changes in the restoring vegetation  of Dashu Mountain National Forest Park, Anhui Province. The characteristics of the communities were determined with Margalef richness index (R), Shannon diversity index (H), Pielou evenness index (J_sw) and Simpson index (D). The results showed that H indexes of tree layers of Pinus massoniana coniferous forest, coniferousbroad leaf mixed forest, Quercus acutissima forest were 1.957, 1.485 and 0.738, respectively, while that of the Tilia breviradiata forest was 1.694. Species richness and species diversity of tree layer in Q. acutissima forest were significantly lower than in the other three communities (P＜0.05), and the evenness index in Q. acutissima forest was significantly lower than in P. massoniana and T. breviradiata forests (P＜0.05). The evenness and species diversity index of shrub and herb layers were not significantly different among the four forests (P＞0.05). As for vertical structure, the species diversity of Q. acutissima forest was in the order of shrub layer＞herb layer＞tree layer, while that of the other 3 communities was in the order of shrub layer＞tree layer＞herb layer. The biodiversity of the climax was not the highest. In addition to human activity, community development stage and its environment were the main driving factors for the species diversity variation of community succession.

Key words: wheat-maize planting system, carbon footprint, wheat-summer direct-seeding peanut planting system, greenhouse gas emissions.