山西省露天煤矿复垦区典型人工林凋落物持水性能研究

Study on water-holding capacity of litters from typical artificial forests in reclaimed regions of the opencast coal mine in Shanxi Province

为了探究煤矿排土场人工林凋落物持水性能对矿区水土保持及生态系统恢复的重要作用,本研究采用野外调查和室内浸提相结合的方法,测定了山西省安太堡露天煤矿排土场4种典型人工林(小叶杨、榆树、油松和刺槐)不同分解阶段凋落物蓄积量、持水率、持水量、吸水速率等持水特性。结果表明:小叶杨和油松凋落物蓄积量显著高于刺槐和榆树(P<0.05);4种人工林不同分解阶段凋落物持水率和持水量与浸水时间均呈极显著对数关系(P<0.01);凋落物吸水速率呈现刺槐>榆树>小叶杨>油松,且吸水速率与浸水时间均存在极显著幂函数关系(P<0.01)。凋落物最大持水量和有效拦蓄量分别为:4.59~8.94 t·hm^(-2)和3.42~7.31 t·hm^(-2),顺序均为:小叶杨>油松>刺槐>榆树。小叶杨凋落物的持水能力最强,而刺槐凋落物吸水速率最快。因此,优先栽植小叶杨,并与刺槐适当混交,对山西省露天煤矿复垦区水源涵养有积极作用。

To study the important effects of the water-holding capacity of litter in plantation plants in coal mine dumps on soil and water conservation and ecosystem restoration in mining areas,litter accumulation amount,the thickness,water-holding rate,water-holding capacity,and water absorption rate of different decomposition stages were investigated in four typical plantations of the same age(Populus simonii,Ulmus pumila,Pinus tabulaeformis,and Robinia pseudoacacia forests)in the Antaibao opencast coal mine reclamation area,through field investigation and soaking extraction.The results showed that the litter accumulation amount in the P.simonii forest was higher than that in the R.pseudoacacia and U.pumila forests(P<0.05).The water-holding capacity and litter rate at different decomposition degrees changed logarithmically with immersion time(P<0.01).The order of the water absorption rate of litter was R.pseudoacacia forest>U.pumila forest>P.simonii forest>P.tabulaeformis forest,and the water absorption rate showed a significant power function with immersion time(P<0.01).In conclusion,the litter of the P.simonii forest had the strongest water-holding capacity,whereas the R.pseudoacacia forest had the fastest water absorption rate.Therefore,from the perspective of the water conservation capacity of litter,P.simonii forest should be prioritized and mixed with the R.pseudoacacia forest,which is more conducive to water conservation in the reclamation area of opencast coal mines.