地理学报 ›› 2020, Vol. 75 ›› Issue (3): 558-570.doi: 10.11821/dlxb202003009
张俊华1,2, 李国栋1,2(), 王岩松1,2, 朱连奇1,2, 赵文亮1,2, 丁亚鹏1,2
收稿日期:
2019-05-17
修回日期:
2020-01-14
出版日期:
2020-03-25
发布日期:
2020-05-25
作者简介:
张俊华(1975-), 女, 河南舞阳人, 博士, 教授, 主要从事土壤碳氮特征与土壤质量研究。E-mail: oklgd@163.com
基金资助:
ZHANG Junhua1,2, LI Guodong1,2(), WANG Yansong1,2, ZHU Lianqi1,2, ZHAO Wenliang1,2, DING Yapeng1,2
Received:
2019-05-17
Revised:
2020-01-14
Published:
2020-03-25
Online:
2020-05-25
Supported by:
摘要:
黄河泥沙是黄河下游陆地地貌类型形成的物质来源,泥沙沉积改变了地表土壤结构和有机碳含量水平。基于室内外实验和空间地统计分析方法,文中对开封—周口土壤有机碳组分的空间特征和影响因素进行了分析。在0~100 cm土壤中TOC、AOC、NOC的含量分别为0.05~30.03 g/kg、0.01~8.86 g/kg和0.02~23.36 g/kg,表层0~20 cm的TOC、AOC、NOC高于下层,同一土层中TOC的变化幅度和含量差异性最大,AOC最小,NOC介于二者之间。NOC的含量对TOC的贡献大于AOC。空间地统计学研究显示,TOC、AOC、NOC的块金系数在0.50~0.67之间,具有中等程度的空间相关性,TOC、AOC、NOC的含量受结构因素和随机因素的共同作用,且二者的作用强度接近。空间上,自表层向下层,土壤TOC、AOC和NOC的整体变化趋势较为一致,高值区与低值区之间过渡明显,NOC和AOC的含量及空间变化能较好地反映TOC的空间变化和碳积累区域。分析发现,黄河泥沙冲/沉积区分布、农业耕作过程和耕作历史是影响区内土壤有机碳及其组成含量和空间分布的主要因素,而有机物的输入量、土壤颗粒物组成及二者的动态关系是影响土壤结构体形成和有机碳含量的关键因素,提高有机物的含量和改善土壤结构是提升土壤质量、实现区内农业持续发展的有效途径。
张俊华, 李国栋, 王岩松, 朱连奇, 赵文亮, 丁亚鹏. 黄河泥沙冲/沉积区土壤有机碳不同组分空间特征及变异机制[J]. 地理学报, 2020, 75(3): 558-570.
ZHANG Junhua, LI Guodong, WANG Yansong, ZHU Lianqi, ZHAO Wenliang, DING Yapeng. Spatial characteristics and variation mechanism of different soil organic carbon components in the alluvial/sedimentary zone of the Yellow River[J]. Acta Geographica Sinica, 2020, 75(3): 558-570.
表1
不同深度土壤有机碳及其组分含量的统计特征(g/kg)
指标 | 深度(cm) | 极差 | 最小值 | 最大值 | 平均值 | 方差 | 偏度 | 峰度 |
---|---|---|---|---|---|---|---|---|
TOC | 0~20 | 28.78 | 1.25 | 30.03 | 8.96±4.31 | 18.62 | 0.99 | 2.44 |
20~40 | 16.72 | 0.59 | 17.32 | 5.08±2.87 | 8.24 | 1.12 | 1.81 | |
40~60 | 13.60 | 0.40 | 14.00 | 3.88±2.50 | 6.25 | 1.01 | 1.19 | |
60~80 | 15.73 | 0.08 | 15.81 | 3.08±2.24 | 5.02 | 1.56 | 4.64 | |
80~100 | 13.78 | 0.05 | 13.83 | 2.57±2.12 | 4.50 | 1.66 | 4.34 | |
AOC | 0~20 | 8.75 | 0.11 | 8.86 | 1.77±1.07 | 1.15 | 1.70 | 8.52 |
20~40 | 3.47 | 0.01 | 3.48 | 0.80±0.62 | 0.38 | 1.19 | 1.84 | |
40~60 | 1.98 | 0.01 | 2.00 | 0.51±0.43 | 0.19 | 0.97 | 0.31 | |
60~80 | 1.49 | 0.01 | 1.50 | 0.37±0.34 | 0.12 | 1.00 | 0.15 | |
80~100 | 1.42 | 0.01 | 1.42 | 0.29±0.29 | 0.08 | 1.39 | 1.74 | |
NOC | 0~20 | 22.75 | 0.61 | 23.36 | 7.19±3.48 | 12.13 | 0.95 | 1.98 |
20~40 | 15.27 | 0.58 | 15.85 | 4.28±2.49 | 6.25 | 1.30 | 2.52 | |
40~60 | 12.89 | 0.01 | 12.90 | 3.34±2.22 | 4.95 | 1.14 | 1.87 | |
60~80 | 15.20 | 0.06 | 15.26 | 2.76±2.02 | 4.07 | 1.86 | 6.96 | |
80~100 | 13.23 | 0.02 | 13.25 | 2.25±1.94 | 3.75 | 1.87 | 5.82 |
表2
不同深度土壤有机碳及其组分半方差函数拟合模型及参数
深度 (cm) | 指标 | 模型 | 块金值 (C0) | 基台值 (C0+C) | 变程 (A0) | 块金系数 (C/C0+C) | 决定系数 (R2) | 残差 (RSS) | 分形维数 (D) | |
---|---|---|---|---|---|---|---|---|---|---|
0~20 | TOC | E | 10.91 | 27.56 | 6.52 | 0.60 | 0.91 | 8.37 | 1.92 | |
AOC | E | 0.72 | 1.41 | 1.55 | 0.50 | 0.83 | 0.08 | 1.91 | ||
NOC | E | 6.95 | 14.79 | 4.04 | 0.53 | 0.90 | 3.92 | 1.92 | ||
20~40 | TOC | E | 4.56 | 13.28 | 9.03 | 0.66 | 0.93 | 1.11 | 1.92 | |
AOC | E | 0.71 | 1.43 | 1.55 | 0.50 | 0.83 | 0.08 | 1.96 | ||
NOC | E | 3.36 | 9.79 | 7.73 | 0.67 | 0.93 | 0.70 | 1.91 | ||
40~60 | TOC | E | 2.92 | 6.31 | 3.21 | 0.54 | 0.95 | 0.46 | 1.91 | |
AOC | E | 0.11 | 0.22 | 0.78 | 0.50 | 0.86 | 0.00 | 1.93 | ||
NOC | E | 2.27 | 4.68 | 2.51 | 0.52 | 0.92 | 0.44 | 1.91 | ||
60~80 | TOC | E | 2.18 | 5.06 | 3.35 | 0.57 | 0.94 | 0.38 | 1.90 | |
AOC | E | 0.10 | 0.20 | 0.66 | 0.50 | 0.85 | 0.00 | 1.94 | ||
NOC | G | 1.81 | 3.62 | 1.23 | 0.50 | 0.93 | 0.35 | 1.89 | ||
80~100 | TOC | G | 1.86 | 3.72 | 0.97 | 0.50 | 0.93 | 0.49 | 1.89 | |
AOC | E | 0.08 | 0.22 | 0.39 | 0.63 | 0.68 | 0.00 | 1.94 | ||
NOC | G | 1.53 | 3.07 | 0.89 | 0.50 | 0.90 | 0.46 | 1.88 |
表3
不同深度土壤有机碳及其组分空间分布的模拟误差
深度 (cm) | 指标 | 平均误差 (ME) | 均方根误差 (RMSE) | 平均标准误差 (ASE) | 均方误差 (MSE) | 均方根标准误差 (RMSSE) |
---|---|---|---|---|---|---|
0~20 | TOC | 0.02 | 3.50 | 3.50 | 0.01 | 0.99 |
AOC | 0.01 | 0.99 | 0.87 | 0.01 | 1.13 | |
NOC | 0.00 | 2.83 | 2.81 | 0.00 | 1.01 | |
20~40 | TOC | 0.01 | 2.28 | 2.27 | 0.01 | 1.01 |
AOC | 0.01 | 0.56 | 0.58 | 0.02 | 0.95 | |
NOC | 0.00 | 1.99 | 1.95 | 0.01 | 1.02 | |
40~60 | TOC | 0.04 | 1.89 | 1.81 | 0.00 | 1.04 |
AOC | 0.00 | 0.38 | 0.33 | 0.01 | 1.15 | |
NOC | 0.00 | 1.69 | 1.59 | 0.00 | 1.06 | |
60~80 | TOC | 0.00 | 1.70 | 1.62 | 0.00 | 1.07 |
AOC | 0.00 | 0.33 | 0.27 | 0.00 | 1.20 | |
NOC | 0.01 | 1.57 | 1.38 | -0.01 | 1.14 | |
80~100 | TOC | -0.02 | 1.50 | 1.40 | -0.01 | 1.09 |
AOC | 0.02 | 0.41 | 0.39 | 0.01 | 1.11 | |
NOC | -0.01 | 1.40 | 1.27 | -0.01 | 1.11 |
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