高寒草原不同种草方式对流动沙丘植被恢复的影响

Effects of Different Grass Planting Methods on Vegetation Restoration of Moving Sand Dune in Alpine Grassland

[目的]研究种草方式对流动沙丘植被恢复效果的影响,为高寒草原沙化土地治理提供技术支持。[方法]在甘肃省玛曲县流动沙丘,设置不同播种方式、不同草种和不同种草模式试验,分析不同种草方式对植被恢复的影响。[结果]撒播和条播对植被恢复无显著影响。总体上草种对植被恢复影响不大,流动沙丘植被恢复中只需种植垂穗披碱草(Elymus nutans)即可。种草模式对植被恢复影响很大。牧草种植第2年,与没有铺施牛羊粪的种草模式相比,铺施牛羊粪种草模式下牧草高度、密度、盖度、地上生物量鲜重和干重均显著且大幅增加,同样铺施牛羊粪的模式中,牛羊粪厚度约2 cm的牛羊粪+无沙障模式下牧草高度和盖度显著地高于牛羊粪厚度约1 cm的牛羊粪+沙障模式。牧草生长状况与土壤养分、持水能力具有良好的正相关关系。[结论]牛羊粪+无沙障种草模式是研究区流动沙丘植被恢复的最优模式。铺施牛羊粪厚度达到约2 cm,就再无必要设置其他沙障进行固沙。

[Objective]To provide technical support for desertification control,the effects of grass planting methods on vegetation restoration of moving sand dunes in alpine grasslands were studied.[Methods]On a moving sand dune of Maqu County,Gansu Province,experiments involving different seeding modes,different grass species,and different grass planting modes were conducted to analyze the effects of different grass planting methods on vegetation restoration.[Results]Broadcast seeding and drill seeding had no significant effect on vegetation restoration.Overall,grass species had little effect on vegetation restoration,and it was only necessary for planting Elymus nutans in the vegetation restoration of moving dunes.The planting mode had a significant effect on vegetation restoration.In the second year of grass planting,the height,density,coverage,above-ground biomass fresh weight,and dry weight of grass were significantly increased in paving cow and sheep dung mode compared with no paving cow and sheep dung mode.In the same modes of paving cow and sheep dung,the height and coverage of grass were significantly higher in"cow and sheep dung+no sand barrier grass"mode with a thickness of cow and sheep dung of approximately 2 cm than in"cow and sheep dung+sand barrier grass"mode with a thickness of cow and sheep dung of approximately 1 cm.The grass growth status was positively correlated with soil nutrient and water holding capacity.[Conclusion]"Cow and sheep dung+no sand barrier"grass planting mode was the optimal mode of vegetation restoration of moving dunes in the study area.If the thickness of the cow and sheep dung was approximately 2 cm,it was no longer necessary to set other sand barriers for sand fixation.