陕北沙区煤矸石山适宜的覆沙厚度试验研究

Experimental Research on Suitable Sand Thickness in Coal Gangue Waste Land in Sandy Area of Northern Shaanxi Province

[目的]解决陕北沙区煤矸石废弃地占地面积大,植被恢复困难和治理造价高的问题。[方法]利用野外试验,设计半隐蔽沙蒿沙障(2m×2m)下的3种覆沙厚度(30,50和70cm)共3种类型的处理。4种乡土灌木树种沙地柏(Sabina chinensis)、长柄扁桃(Amygdalus pedunculata)、紫穗槐(Amorpha fruticosa)和蒙古莸(Caryopteris mongholica)进行对比试验。[结果]成活率、保存率、新稍生长量和地径变化随着覆沙厚度的增加,其指标均有所提高;多因素方差分析表明种间存在极显著差异,在0.05的显著水平下,紫穗槐与其它植物种均存在显著差异,蒙古莸与沙地柏间存在显著差异;在0.01显著水平下,蒙古莸、长柄扁桃和沙地柏间差异性不显著;覆沙30cm与覆沙50cm,覆沙70cm间均存在显著差异,覆沙50cm和覆沙70cm间差异性均达不到显著水平。[结论]综合因素条件下,覆沙50cm是该区域煤矸石山土地复垦及生态恢复植被需要基质的最佳选择。

[Objective]To solve the issues of large coal gangue waste land area and high cost in vegetation restoration in sandy area of Northern Shaanxi Province.[Methods]Three sand thickness（30,50 and 70cm）and a semi-covered Artemisiasand barrier（2m×2m）were set.Four different kinds of native shrub species including Sabina chinensis,Amygdalus pedunculata,Amorpha fruticosa and Caryopteris mongholica were selected for the experiments.[Results]The survival rate,saving rate,the amount of new growth and diameter had improved due to the increase of sand thickness.Multi-factor variance analysis showed that there were significant differences among different species.Significant differences were found between A.fruticosa Linn and other types,and between C.mongholica Bunge and S.vulgaris（p〈0.05）.There were no significant difference between C.mongholicaBunge,A.pedunculataPall and S.vulgaris（p〈0.01）.There were significant differences among the 30,50 and 70cm sand thickness,and there were no significant differences between 50 cm and 70 cm sand.[Conclusion]With the consideration of all factors,a sand thickness of 50 cm is optimal in land reclamation and ecological restoration in the coal gangue waste land.