腾格里沙漠东北缘飞播30 a人工林土壤养分特征

In order to clarify the effect of vegetation restoration on soil nutrient accumulation in the aerial seeding afforestation area of the northeastern margin of the Tengger Desert in 1992. In this paper, the Calligonum mongolicum community and mixed community ( Hedysarum scoparium + Calligonum mongolicum ) formed in the aerial seeding area were studied to analyze the variation law and cumulative effect of soil nutrients.The results showed that : ( 1 ) Vegetation restoration significantly increased the soil nutrient content in the aerial seeding area. The soil organic matter ( SOM ), total nitrogen ( TN ), total phosphorus ( TP ), and total potassium ( TK ) of the Calligonum mongolicum community and the mixed community increased by 60 % ~105 %, 123 %~161 %, 129 % ~149 %, and 145 % ~261 %, respectively. The increase of the Calligonum mongolicum community was significantly higher than that of the mixed community and the bare sand ( CK ) ( P < 0.05 ). The vertical distribution of nutrients showed a surface accumulation effect, and the content of 0~10 cm soil layer was significantly higher than that of 150 200 cm soil layer. ( 2 ) The two communities had a positive effect on nutrient accumulation in 0-200 cm soil layer, and the effect decreased with the increase of depth ( P < 0.05 ). The mean positive effect of C.mongolicus community ( 0.39 ) was significantly higher than that of mixed community ( 0.29 ).( 3 ) The soil nutrient recovery index of Calligonum mongolicum community and mixed community were 62.19 % and 51.63 %, respectively. The results showed that after 30 years of aerial seeding afforestation in the northeastern margin of Tengger Desert, soil nutrients were significantly improved, and the promotion effect of Calligonum mongolicum community on nutrient accumulation was slightly better than that of mixed community, which could provide a theoretical basis for the restoration and stable maintenance of artificial sand-fixing vegetation in arid areas.