毛乌素沙地樟子松人工林土壤物理性质的时空变异规律

以毛乌素沙地榆林沙区樟子松人工林土壤为研究对象,分析不同林龄樟子松人工林土壤质量含水量、土壤体积质量、孔隙度时空变异规律。结果表明,土壤质量含水量在流沙地为丘间地>迎风坡>背风坡>丘顶,在樟子松人工林为丘间地>背风坡>迎风坡>丘顶,并随土层深度增加而增加,0～5cm土层质量含水量樟子松人工林高于流沙地,5～25cm和25～50cm土层低于流沙地。土壤体积质量在流沙地为丘顶>迎风坡>背风坡>丘间地,在樟子松人工林为丘顶>中部(迎风坡、背风坡)>丘间地,随土层深度增加而增加,且樟子松人工林对应各层土壤体积质量均小于流沙地。毛管孔隙度均为丘间地>中部(迎风坡、背风坡)>丘顶,土壤孔隙度(总孔隙度、毛管孔隙度、非毛管孔隙度)随土层深度增加而降低,樟子松人工林对应各层土壤孔隙度均大于流沙地。随樟子松林龄增加,质量含水量和孔隙度分别增加1.32%～21.82%、2.88%～12.00%,土壤体积质量降低1.16%～7.12%。统计分析表明,所测指标总体上存在显著差异。

Spatio temporal Variabilities of Soil Physical Properties of Pinus sylvestris var.mongolica Artificial Forest in Mu Us Desert

In this thesis,the soil of Pinus sylvestris var.mongolica artificial forest in Yulin sandy area of Mu Us Desert was researched,and the spatio-temporal variabilities of mass water content,soil bulk density and soil porosity of Pinus sylvestris var.mongolica with different stand ages in Mu Us Desert was analyzed.The results showed as follows:the mass water content of quicksand appeared interdune > windward > leeward > dunt top.The mass water content of Pinus sylvestris var.mongolica artificial forest presented interdune > leeward > windward > dunt top,and the mass water content increased as the soil layer deepened.The mass water contents of 0-5 cm soil layer of Pinus sylvestris var.mongolica forest were higher than those of quicksand,and the mass water contents of 5-25 cm and 25-50 cm soil layers were lower than those of quicksand.The soil volumic mass of quicksand emerged dunt top > windward > leeward > interdune,and the soil volumic mass of Pinus sylvestris var.mongolica artificial forest showed dunt top > middle(windward,leeward) > interdune.The soil volumic mass increased as the soil layer deepened,and the soil volumic mass of each corresponding soil layer of Pinus sylvestris var.mongolica artificial forest were lower than those of quicksand.The capillary porosities all displayed interdune > middle(windward,leeward) > dunt top,and the soil porosities(total porosity,capillary porosity,non-capillary porosity) reduced as the soil layer deepened,and the soil porosities of each corresponding soil layer of Pinus sylvestris var.mongolica artificial forest were higher than those of quicksand.With the stand age of Pinus sylvestris var.mongolica growing,the mass water content and the soil porosity increased by 1.32%-21.82%,2.88%-12.00% respectively,and the soil volumic mass decreased by 1.16%-7.12%.Results from statistic analysis showed that there were significant differences at 5% level in all assayed characters.