干旱区土壤剖面无机碳分布及其与盐碱性的关系

发布时间：2018-06-15 05:55

本文选题：土地利用 + 土壤无机碳　；参考：《水土保持学报》2017年05期

【摘要】：土壤无机碳作为干旱区土壤碳库的主要存在形式,其数量分布影响着区域内土壤剖面碳聚积和存储的格局。以往由于缺乏深层土壤剖面数据,无法准确量化土壤剖面碳分布与碳存储特征,使得土壤无机碳的数量存在很大的不确定性。以三工河流域典型的农田和相邻荒地土壤作为研究对象,共6个剖面190个采样点,挖掘取样深度至潜层地下水位,分析了剖面土壤无机碳(SIC)和可溶性盐离子的分布特征,并且通过冗余分析探究无机碳与土壤盐碱性之间的相互关系。结果表明:(1)农田的SIC含量显著大于荒地的SIC含量(p0.05),相比于荒地,农田的SIC含量增加了27.9%,变化范围增大了3.66倍;荒地和农田的SIC含量在剖面上分别表现为"S"形和"M"形分布。(2)在整个剖面上,同层次的农田土壤中的可溶性离子含量显著小于荒地中的含量(p0.05),并且在剖面上分布荒地表现为增加—减少趋势,而农田为逐渐减小趋势,表明农业活动显著改变了可溶性离子的数量和分布特征。(3)所有剖面土壤无机碳储量为0—100cm土层100—300cm土层300cm以下土层(p0.05),虽然层次间其数值差异较大,但在相同层次,农田和荒地的土壤无机碳储量所占比例却基本相同,为10%,35%,55%(p0.05)。(4)通过冗余分析得到土壤盐碱性因素对SIC的贡献作用排序,正相关性,pHESPSARCO_3~(2-)HCO_3~-;负相关性,K~+Ca~(2+)Mg~(2+)Cl~-盐分SO_4~(2-)Cl~-Na~+。
[Abstract]:Soil inorganic carbon is the main form of soil carbon pool in arid area, and its quantity distribution affects the pattern of carbon accumulation and storage in soil profile. In the past, because of the lack of deep soil profile data, it was impossible to quantify the carbon distribution and carbon storage characteristics of soil profile accurately, which made the amount of soil inorganic carbon very uncertain. The typical farmland and adjacent wasteland soil in Sangong River Basin were used as the research objects. There were 190 sampling sites in 6 sections, and the sampling depth to the groundwater level of the subsurface layer was excavated. The distribution characteristics of soil inorganic carbon and soluble salt ions in the profile were analyzed. The relationship between inorganic carbon and soil salt alkalinity was studied by redundancy analysis. The results showed that the sic content in the farmland was significantly higher than that in the wasteland (p 0.05). Compared with the barren land, the sic content in the farmland increased by 27.9g / L and the range of variation was 3.66 times higher than that in the barren land. The sic contents of wasteland and farmland were distributed in "S" shape and "M" shape, respectively, in the whole section. The content of soluble ions in the soil of the same level was significantly lower than that in the wasteland, and the distribution of the wasteland in the profile showed an increasing-decreasing trend, while the farmland showed a decreasing trend. The results showed that agricultural activities significantly changed the quantity and distribution of soluble ions. (3) all soil inorganic carbon reserves in the profile were 0-100cm soil layer, 100-300cm soil layer, soil layer (p 0.05), although there were great differences among layers, but at the same level, the content of inorganic carbon in soil profile was lower than that in 100-300cm soil layer. The proportion of inorganic carbon storage in soil of farmland and wasteland is basically the same, that is, 10 / 3555 / 55) the contribution of soil salinity-alkali factors to sic is obtained by redundancy analysis, the positive correlation is pHESPSARCO3- (2-HCO3-); the negative correlation is K ~ CaSARCO3C ~ (2) Mg-Cl2 / C ~ (2) -salt SO4T _ 2-Cl-Na ~ (-Na ~).
【作者单位】：中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室;中国科学院阜康荒漠生态系统国家野外科学观测站;中国科学院大学;
【基金】：新疆自治区杰出青年科技创新人才培养项目(2014711009) 国家自然科学基金项目(41371200,41671114) 中科院西部之光项目(2015-XBQN-A-06)
【分类号】：S153.6

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