人工恢复与自然恢复模式下苔草草丘生态特征比较

本研究以哈尔滨太阳岛草丘湿地为对象,对比了人工恢复与自然恢复下苔草草丘个体和种群的生态特征,并分析其与环境因子的关系.结果表明:苔草植株生长随时间呈现先增加后降低的变化趋势(5—8月),初期(5—6月)生长迅速,6月达到峰值.人工恢复和自然恢复模式下,苔草草丘个体和种群特征差异显著:自然恢复下苔草叶面积、叶宽、单株鲜重、单株干重、丘墩高度、直径、丘顶面积、丘墩表面积、丘墩体积等苔草草丘个体特征均显著高于人工恢复,人工恢复下苔草草丘密度、盖度、生物量等种群特征显著高于自然恢复,物种多样性无显著差异.土壤含水量、水深、草丘密度、丘间距离是导致2种恢复模式下苔草草丘生长差异的主要因素,自然恢复区土壤含水量、水深、间距均显著高于人工恢复区,对草丘个体的形成和发育具有促进作用,人工恢复区高移栽密度是导致草丘密度、盖度、生物量高于自然恢复区的主要因素.建议未来开展苔草草丘湿地恢复和保护时,应参考自然恢复湿地中草丘的分布特点,适当调整丘间距离(54.22～117.89 cm)和种群密度(1.9～3.1 墩·m^-2),同时采取干旱区春季适当补水措施,保持适宜的土壤含水量和水深,促进苔草草丘的生长发育和快速恢复,维持其种群长期健康稳定.

Comparison of ecological characteristics of Carex tussock under natural and artificial reco-very.

We compared the ecological characteristics of tussock individuals and populations undergoing natural and artificial restoration in Carex tussock wetlands in the Sun Island in Harbin and identified the relationships between the growth of Carex tussock and environmental factors. Results showed that there were obvious seasonal dynamics in morphological characteristics of C. appendiculata. Tussocks grew rapidly from May to June, peaked in June, and then decreased steadily from July to August. There were significant differences in ecological characteristics of Carex tussocks between natural and artificial restorations. The morphological characteristics of individual tussock, including leaf area, leaf width, fresh weight per ramet, dry weight per ramet, and the hummock shape indicators (hummock height, diameter, volume and surface area) in natural restored area were significantly higher than those in artificial transplanting area. For the Carex tussock community, tussock density, coverage and biomass in natural restoration area were significantly lower than those in artificial transplanting area. Soil water content, water depth and hummock spacing in natural restoration area were significantly higher than those in artificial restoration area, which facilitated the formation and development of individual tussock. Higher transplanting density was the main factor leading to higher density, coverage, and biomass in artificial restoration area. Our results suggested that the distribution characteristics of tussocks in natural restoration area should be taken into account in future restoration and protection works. Appropriate adjustment of the distance between hummock (54.22-117.89 cm) and population density (1.9-3.1 ind·m^-2), as well as proper water recharge measures in spring in arid areas to regulate soil water content and water depth, would be conducive to promoting the growth and rapid recovery of Carex tussock, which would maintain the long-term health and stability of tussock wetland.