关键词: 扩展, 比叶面积, 叶片养分含量, 干物质含量, 适应策略

Abstract: [Objective] This study aims to reveal the changing patterns of the leaf functional traits of moso bamboo and Chinese fir, and explore the adaptability and survival strategy of moso bamboo and Chinese fir during the expansion of moso bamboo to Chinese fir forest.[Method] Three 10 m×50 m transects were set along the expansion direction from moso bamboo to Chinese fir plantation, and each transect was divided into 10 subplots (a size of 5 m×10 m). In each subplot, standard culms/stems of moso bamboo at different ages and Chinese fir were selected. Leaves were collected on these trees to measure the specific leaf area (SLA), leaf dry matter content (LDMC), leaf carbon content (C), leaf nitrogen content (N), leaf phosphorus content (P) and calculate the ratios.[Result] 1) During the expansion process of moso bamboo to Chinese fir, SLA of moso bamboo and Chinese fir was significantly negatively related with the ratio of moso bamboo, except Ⅰ du bamboo, while LDMCs were significantly positively related with the ratio of moso bamboo. The mean SLAs of Ⅰ, Ⅱ, Ⅲ and Ⅳ bamboo were 291, 215, 207 and 213 m²·kg^-1, respectively, and the LDMC of Ⅰ, Ⅱ, Ⅲ and Ⅳ bamboo was 0.38, 0.40, 0.42 and 0.42 g·g^-1, respectively. The two parameters were significantly higher than those of Chinese fir (115 m²·kg^-1 for SLA and 0.34 g·g^-1 for LDMC, P < 0.005). 2) For Ⅰ and Ⅳ bamboo, leaf C, N and P contents of moso bamboo showed an increasing trend with the ratio of moso bamboo. Meanwhile, a decreasing trend with the ratio of moso bamboo was observed for Ⅱ, Ⅲ and Chinese fir leaves. Leaves of Ⅰ, Ⅱ, Ⅲ and Ⅳ had 46.5%, 46.1%, 45.5% and 46.0% C contents, respectively, 27.6, 22.3, 21.7 and 20.8 g·kg^-1 N content, and 1.6, 1.4, 1.2, and 1.2 g·kg^-1 for P content. The N and P contents of moso bamboo were significantly higher than those of Chinese fir (13.6 and 1.0 g·kg^-1, respectively). 3) There were significant or extreme significant relationships between bamboo SLA, LDMC and leaf C, N, P contents, C:N and N:P.[Conclusion] Compared to Chinese fir, moso bamboo had larger SLA, and higher N and P contents, and during its expansion to Chinese fir, the main leaf functional traits of moso bamboo at different ages adapted differently with a complementary effect, which can make use of the resources more effectively.

Key words: expansion, specific leaf area, nutrient content in leaf, dry matter content in leaf, survival strategy