排矸场植被恢复初期不同植被类型土壤优先流特征

以宁夏羊场湾排矸场草地(G)、灌丛(S)和乔木(A)为研究对象,通过染色示踪试验分析排矸场植被恢复初期不同植被类型的优先流特征。结果表明:1)A水分损失最严重,最大染色深度与优先流程度A>G>S。2)根长密度和根重密度均可促进优先流发育,且≤1 mm根长密度与根重密度的促进作用最明显。3)总染色面积比与最大和最小染色深度、基质流深度显著正相关,与优先流比显著负相关(P<0.05)。4)A和G以20~250mm染色路径为主,S的变化更为复杂。5)各样地以高相互作用大孔隙流为主;土层深度<13cm时,S均质流明显,G和A以非均质指流、高相互作用大孔隙流和混合作用大孔隙流交替出现。

Soil preferential flow characteristics of different vegetation types in the early stage of vegetation restoration in gangue dump

To analyze the preferential flow characteristics of different vegetation types in the early stage of vegetation restoration in gangue dump,dyeing experiments were conducted in grassland(G),shrubland(S)and arbor plot(A)in Yangchangwan gangue dump of Ningxia.The results showed that:(1)Water loss was the most serious in grassland,and the maximum stained depth and the degree of preferential flow were A>G>S.(2)Preferential flow could be promoted by root length density and root weight density,and the promotion effects of root with length less 1 mm density and root weight density were more obvious.(3)The total stained coverage was significantly positively correlated with the maximum and minimum stained depths,and matrix flow depth,while negatively correlated with the preferential flow ratio(P<0.05).(4)The proportion of stained path with width of 20-250 mm was the largest in A and G.However,the change of S was more complicated.(5)Highly interacted macropore flow was dominant in each plot.Homogeneous flow was obvious in S when the soil depth was less than 13 cm,while heterogeneous figure flow,highly interacted macropore flow,mixed macropore flow alternately appeared in A and S.