半干旱矿区侵蚀营力对黑沙蒿根系生长特性的影响及其自修复

以半干旱矿区典型分布的黑沙蒿为研究对象,通过野外原位不离体试验,模拟侵蚀拉拔破坏对黑沙蒿根系生长特性的影响,并分析其受损自修复能力,旨在揭示植物根系在脆弱生态区中抵御外力侵蚀的生存策略.结果 表明,拉拔破坏形成机械损伤后,根系生长速率和活性均明显降低,持续拉拔对二者的抑制作用显著大于瞬时拉拔,重度损伤产生的负反馈显著大...

Effects of erosive agent on root growth and self-healing of Artemisia ordosica in semi-arid mining site

To reveal plant root strategies against external erosion in ecologically fragile zones, we conducted an in situ simulation field experiment to examine the effects of drawing damage on root growth of Artemisia ordosica in semi-arid mining site, and analyzed the self-healing ability of root after erosion. The results showed that the relative growth rate and activity of roots were significantly decreased after being damaged by drawing. The negative effects of persistent drawing on growth rate and activity were significantly greater than that of instantaneous drawing, and that of severe damage was significantly greater than mild damage. A. ordosica roots would die when mechanical damage formed after drawing damage, resulting in higher reduction rate of living root numbers than that of the control. Instantaneous and persistent drawing resulted in a reduction of 60.6% and 66.9% of live roots, respectively. The number of live roots was decreased by 59.7% and 67.8% after mild and severe damage, respectively. After drawing damage, the relative growth rate and activity-repairing rate of A. ordosica roots gradually increased with repair time. Due to the limited self-healing ability, negative impacts caused by erosion damage could not be effectively eliminated. The average repair rate of growth was 56.8%, while the repair rate of activity was 70.5%. In conclusion, the growth characteristics and self-healing ability of roots should be fully considered during vegetation restoration in the frequently eroded areas, in order to ensure the adaptation of plants to the adverse environment and their role in ecological functions such as soil stabilization and erosion resistance.