沙漠前沿不同植被恢复模式的生态服务功能差异

沙漠是具有生态脆弱性和生态功能特殊性的生态系统,其生态系统的恢复与重建,更多的是考虑其防风固沙、生物多样性的产生与维持、气候调节、土壤保护等非实物型生态服务功能的发挥。根据植被样地调查、土壤分析和风因子监测等相关数据,开展了新疆奇台县沙漠前沿不同植被恢复模式的生态服务功能差异研究。结果表明:人工植被恢复模式较天然植被恢复模式对风速和风动能的消抵作用明显,人工植被恢复区比天然植被恢复区多58.8 d/a无风天;年均降低风速0.88 m/s,消抵65.2%的风动能,人工植被恢复对北向和西北向风的消抵作用最显著,对西南向风的消抵作用最弱;不同植被恢复模式的生物多样性保育功能差异较大,天然植被恢复的植物群落较之人工植被恢复的植物群落,物种丰富度指数和Shannon-Wiener指数更高,Pielou指数则相对较低,天然恢复的植物群落的稳定性更高,其维持、繁衍和保持植物多样性的能力更强;不同植被恢复模式对土壤部分化学性质的影响有明显差异,人工植被恢复模式能够通过植物的生理代谢,降低沙漠前沿土壤的含盐量和pH值,但对土壤有机质含量影响不显著。上述研究结果可以为高效的沙漠前沿植被恢复模式的筛选提供必要的理论支撑。

The differences of ecosystem services between vegetation restoration modelsat desert front

Desert is a fragile ecosystem with special function. The restoration of desert ecosystem is positioned on its functions of wind defending, biodiversity conservation, climate regulation, and soil fertility. Based on the data of vegetation structures, soil properties, and wind factors, the difference of ecosystem services was assessed between two restoration models, the natural and planted vegetation restoration areas in the desert of Qitai County, Xinjiang Uygur Autonomous Region, NW China. The results showed that, there were 58.8 more days without wind per year in the planted than in the natural vegetation restoration area. Average wind velocity and kinetic wind energy were lowered by 0.88 m/s and 65.2%, respectively, in the planted than in the natural vegetation restoration area. Compared with the natural recovered area, the planted area was better in reducing winds from the north and the northwest, but weaker in reducing wind from the southwest. Compared with the planted restoration model, the natural recovery model was better in conserving plant biodiversity, the species richness and Shannon-Wiener index of plant communities in the natural recovery area were much higher than those in the planted restoration area, but the tendency of Pielou index was on the contrary. The plant community in the natural recovery area was more stablein that its soil salt and pH were higher than those in the planted restoration area. These results might be meaningful for selecting effective restoration model at desert front.