摘要:
为进一步验证浸提条件对黑土表层土壤溶解性有机碳(DOC)浸提量的影响,并筛选出适于比较黑土区不同 土地利用类型土壤DOC 差异的浸提条件,以典型黑土区落叶松人工林、天然草地、耕地和天然次生林0 ~ 10 cm 土 层土壤为实验材料,测定了不同水土质量比、浸提剂种类及温度条件下4 种土地利用类型表层土壤溶解性有机碳 浸提量。结果表明:1)4 种土地利用类型表层土壤溶解性有机碳浸提量均随水土质量比的增加而增大,呈显著的线 性关系(R2 为0.82 ~0.98);当水土质量比为40颐1时4 种样地土壤DOC 浸提量差异显著(P 0.05),且以天然次生 林土壤DOC 最高,分别为落叶松人工林、草地和耕地的1郾16、1.8 和1.1 倍。2)浸提剂种类不同对表层土壤DOC 测定结果具有一定影响,其中以去离子水提取的土壤DOC 较大。3)在20 ~ 70 益范围内,DOC 浸提量随浸提温度 的升高呈现无明显规律性,其中以70 益时4 种样地表层土壤DOC 浸提量差异显著(P 0.5)。可以认为40:1 水土质量比、去离子水作浸提剂的浸提条件可以反映黑土区不同土地利用类型表层土壤DOC 之间的差异。
Abstract:
Aiming to confirm the effects of extraction methods on the concentration of topsoil dissolved organic carbon (DOC) and select suitable conditions for extracting DOC of black soil, topsoil samples in the depth of 0-10cm collected from four land use types, including Dahurian larch plantation, natural grassland, arable land and natural secondary forest from black soil, were used by measuring the concentration of DOC extracted with different water-to-soil mass ratios, extractants and temperatures. Results showed that: 1) the concentration of DOC extracted from topsoil presented a positive linear relationship significant with water-to-soil mass ratio (R2 ranged in 0.82-0.98). The differences of DOC concentrations in topsoil of four land use types were significant (P 0.05) when the water-to-soil mass ratio was 40:1 with a peak value in the natural secondary forest, which was 1.16, 1郾88 and 1郾61 times of larch plantation, natural grassland and arable land, respectively. 2) The type of soil extractant also had influence on concentration of DOC in topsoil to some degree. DOC extracted with deionized water resulted in a higher concentration compared with other conditions. 3) The extraction concentration of DOC under four land use types did not show a significant regularity until the temperature increased to 70 益(P 0郾05). It can propose a relatively appropriate extraction procedure for DOC concentration from topsoil, and which can reflect its differences among the land use patterns of black soil: field鄄moist soil extracted with deionized water at a 40:1 water-to-soil mass ratio.
百度学术
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