铁尾矿修复植物选择研究

The research of plant selection for iron tailings repairing

针对铁尾矿植被恢复时植物可选种类少、适应性差,影响植被修复技术推广的现状,在唐山首钢马兰庄镇铁尾矿废弃地上直接播种紫苜蓿、紫穗槐、皂荚、暴马丁香、刺槐5种植物,对每种植物的株高、地径、根长、地上生物量、地下生物量和根冠比等生长指标进行测定分析,结果表明:到2014年9月,刺槐在5种植物中表现最佳,适应性最强,株高(77.67cm)、地径(6.33cm)、根长(23.97cm)、地上生物量(2 040.19g/m^2)和地下生物量(839.01g/m^2)及这5种指标的年生长量均达最大值;除地径外,紫苜蓿的各项生长指标表现次之;紫穗槐、暴马丁香、皂荚较差。2013年9月,各植物的根冠比由大到小依次为紫穗槐(1.04)、皂荚(0.83)、暴马丁香(0.56)、刺槐(0.37)、紫苜蓿(0.32);2014年9月各植物的根冠比由大到小依次为皂荚(1.71)、暴马丁香(0.91)、紫穗槐(0.80)、紫苜蓿(0.50)、刺槐(0.41)。综合考虑,刺槐和紫苜蓿可分别作为适宜铁尾矿修复的最佳树种和草本植物。

The purpose of the research is to solve the problem that not enough plants can De chosen for iron tailing repairing and the low adaptability of many plants, which have preven- ted the promotion of vegetation restoration technology. Five plants （Medicago sativa L. , Amorpha fruticosa L. , Gleditsia sinensis Lam. , Syringa reticulata （Blume） H. Hara var. amurensis（Rupr. ）J. S. Pringle and Robinia pseudoacacia L. ） were sowed directly in ground of discarded iron tailings at Malan county in Tangshan Shougang of China. The growth indicesof plant height, ground diameter, root length, aboveground biomass, underground biomass and root cap ratio were measured and analyzed. The main results were as follow： Until to September 2014 the growth condition and adaptability of Robinia pseudoacacia L. were the best among 5 plants, the plant height of which was 77.67 cm, ground diameter as 6.33 cm, root length as 23.97 cm, aboveground biomass as 2 040.19 g/m2 , underground biomass as 839.01 g/m2 , and the annual growths of the above indices all reached the maximum compare to the other plants. Except for the ground diameter index, Medicago sativa L. ranked as the second. The growth of Amorpha fruticosa L. , Syringa reticulata （Blume） H. Hara var. arnurensis（Rupr. ）J. S. Pringle and Gleditsia sinensis Lam. were raletively poor. In Septem- ber 2013, the descending order of the root cap ratios of these plants was Amorpha fruticosa L. （1.04）, Gleditsia sinensis Lam. （0.83）, Syringa reticulata （Blume） H. Hara var. amu- rensis（Rupr. ）J. S. Pringle （0.56） ,Robinia pseudoacacia L. （0.37）, and Medicago sativa L. （0.32）. In September 2014,the descending order of the plant root cap ratios was Gleditsia sinensis Lam. （1. 71）, Syringa reticulata （Blume） H. Hara var. amurensis（Rupr. ）J. S. Pringle （0.91）, Amorpha fruticosa L. （0.80）, Medicago sativa L. （0.50）, Robinia pseu doacacia L. （0.41）. With the comprehensive consideration, Robinia pseudoacacia L. is the best tree species of vegetation restoration on the tailings. Medicago sativa L. can be used as the dominant herbaceous plant species for the restoration of iron railings wastelands.