关键词: 朱家尖岛, 生态系统管理, 人为影响, 海岛生态脆弱性, 敏感性分析

Abstract: To investigate the practicability of straw strip incorporation mode in Northeast  China, six straw incorporation modes were arranged in Tieling County, Liaoning Province. Compared to wholelayer rotary tillage (T1S0) and wholelayer plowing tillage (T2S0), the four strawincorporation modes of interrow rotary tillage (T1S1), intervalrow rotary tillage (T1S2), interrow plowing tillage (T2S1) and intervalrow plowing tillage (T2S2) had significant effects on soil water content, root distribution, maize yield and water use efficiency. The plow pan profiles were broken under T2S1 and T2S2, which decreased soil bulk density and improved soil water storage capacity. Total root biomass was increased under T2S1 and T2S2, with enhanced proportions of deep roots in soil profiles. Compared to T1S0, the depths of root length density concentrated area were increased by 46.54% and 49.87% for T2S1 and T2S2, respectively. Compared to T2S0, the depths of root length density concentrated area were increased by 37.50% and 40.70%, respectively. Leaf area index was significantly increased under T2S1 and T2S2, which could delay leaf senescence and improve dry matter accumulation. There was no significant difference in dry matter weight and leaf area index among T2S1, T2S2 and T2S0, but the mean value of T2S1 and T2S2 increased by 25.02% and 21.93% respectively compared with T1S0.  T2S1 and T2S2 resulted in the highest leaf protective enzyme activity and the lowest MDA content. In dry-year, yields of T2S1 and T2S2 were increased by 3.80% and 4.05% respectively compared to T1S0. In wet-year, yields had no significant differences among these treatments. For both years, T2S1 had the highest water use efficiency and followed by T2S2. They had 16.28% and 12.77% higher water use efficiency respectively compared to T1S0. Therefore, mode T2S2 is worth for more popularizing.

Key words: island ecological vulnerability, ecosystem management, anthropogenic disturbance, Zhujiajian Island, sensitivity analysis