紫色土坡耕地耕层质量障碍特征

doi:10.3864/j.issn.0578-1752.2020.07.009

摘要/Abstract

摘要： 【目的】 紫色土坡耕地具有高生产力和强侵蚀性的特点,是长江上游重要的耕地资源,分析坡耕地障碍耕层类型及其对农作物产量的影响,对坡耕地合理耕层构建参数确定、耕层质量调控和坡耕地持续利用具有重要应用价值。本文基于不同地力等级紫色土坡耕地耕层样本,定量化分析坡耕地耕层质量障碍特征。 【方法】 采用障碍度模型及聚类分析研究不同地力等级紫色土坡耕地障碍耕层类型及耕层质量变化特征。 【结果】 （1）不同地力紫色土坡耕地土壤物理属性差异显著,随地力等级降低,地块田面坡度显著变大、有效土层厚度显著变小,当田面坡度由5.1°变为21.7°,农作物产量可下降45%,五级坡耕地心土层缺失现象严重;而土壤肥力属性未表现明显差异,一至四级坡耕地同一地力等级土壤有机质、土壤全氮、阳离子交换量总体表现为耕作层>心土层>底土层,五级坡耕地耕作层与底土层之间各指标差异不显著。（2）一、二级坡耕地各土层土壤质量指数均在0.434-0.528之间,同一地力等级各土层土壤质量指数表现为耕作层>心土层>底土层;土壤物理属性对低产坡耕地土壤质量影响更为显著,五级坡耕地田面坡度指标障碍度为一级坡耕地的80.73倍。（3）紫色土坡耕地障碍耕层可分为3类,即Ⅲ土壤养分限制型、Ⅳ有效土层厚度限制型、Ⅴ田面坡度限制型,土壤物理属性为主要障碍特征时,耕层构型疏松,心土层缺失现象严重,农作物产量较土壤养分限制型坡耕地低25%。 【结论】 紫色土坡耕地耕层质量偏低,障碍耕层包含土壤养分限制型、有效土层厚度限制型、田面坡度限制型3种类型,土壤物理属性为主要限制因素,田面坡度偏大,有效土层厚度浅薄化严重。

关键词: 紫色土, 坡耕地, 耕层质量, 障碍耕层, 障碍度模型, 聚类分析

Abstract: 【Objective】 The purple soil slope farmland is characterized by high productivity and strong erodibility, and is an important cultivated land resource in the upper reaches of the Yangtze River. Analyzing the types of barrier tillage layer of slope farmland and its impact on crop yield has important application value for determining reasonable tillage layer construction parameters, controlling tillage layer quality and sustainable utilization of slope farmland. Based on the sample of cultivated layer of purple soil slope farmland in different soil fertility grades, this paper quantitatively analyzed the quality barrier characteristics of slope farmland.【Method】 In this paper, the obstacle degree model and cluster analysis were used to study the types and quality characteristics of barrier tillage layer in purple soil slope farmland of different soil fertility grades.【Result】 The results showed that: (1) There were significant differences in soil physical properties between purple soil slope farmland with different soil fertility grades. With the decrease of soil fertility grade, the slope of the plot was significantly larger, and the thickness of the effective soil layer of plot was significantly smaller. When the slope of the plot changed from 5.1° to 21.7°, the crop yield could be reduced by 45%. The lack of soil layer in the five-slope farmland was serious. However, the soil fertility attributes did not show significant differences. The soil organic matter, soil total nitrogen and cation exchange capacity of the first to fourth grade slope farmland in the same soil fertility grade were as follows: topsoil layer>subsoil layer>bottom soil layer. There was no significant difference between the topsoil layer and the subsoil layer in the fifth grade slope farmland. (2) The soil quality index of each soil layer in the first and second grade slope farmland was between 0.434 and 0.528. The soil quality index of each soil layer of the same soil productivity grade was characterized by topsoil layer>subsoil layer>bottom soil layer; the soil physical properties had a more significant effect on the soil quality of low-yield slope farmland. The obstacle degree of the slope of the plot of the fifth-grade slope farmland was 80.73 times than that of the first-grade slope farmland. (3) The purple soil slope farmland could be classified into three types, namely, III soil nutrient limited type, IV effective soil layer thickness limited type, and V field surface slope limited type. When the soil physical property was the main obstacle feature, the cultivated layer structure was loose, the subsoil layer was seriously deficient, and the crop yield was 25% lower than that of the soil nutrient-restricted sloping farmland. 【Conclusion】 The quality of the cultivated layer in the purple soil slope farmland was low, and the barrier cultivated layer included three types: soil nutrient limitation type, effective soil layer thickness limitation type, and slope of the plot limitation type. The physical properties of soil were the main limiting factors for the quality of the cultivated layer of purple soil slope farmland. The slope of the field was too large, and the thickness of the effective soil layer was shallow and thin.

Key words: purple soil, slope farmland, cultivated layer quality, barrier cultivated layer, obstacle degree model, cluster analysis

宋鸽,史东梅,曾小英,蒋光毅,江娜,叶青. 紫色土坡耕地耕层质量障碍特征[J]. 中国农业科学, 2020, 53(7): 1397-1410.

Ge SONG,DongMei SHI,XiaoYing ZENG,GuangYi JIANG,Na JIANG,Qing YE. Quality Barrier Characteristics of Cultivated Layer for Sloping Farmland in Purple Hilly Region[J]. Scientia Agricultura Sinica, 2020, 53(7): 1397-1410.

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图/表 8

表1

紫色土坡耕地耕层土壤属性指标及农作物产量"

地块号 Block number	行政区域 Administrative region	土壤紧实度 Soil compaction	耕层厚度 Topsoil thickness (cm)	心土层厚度 Subsoil layer thickness (cm)	有效土层厚度Effective thickness of soil layer (cm)	田面坡度 Slope (°)	土壤有机质 Soil organic matter (g·kg^-1)	阳离子交换量 Cation exchange capacity ( cmol(+)·L^-1)	土壤全氮 Soil total nitrogen (g·kg^-1)	土壤有效磷 Soil effective phosphate (mg·kg^-1)	农作物产量 Crop yield (t·hm^-2)	地力等级 Productivity grade of cultivated land
1	万州区 Wanzhou District	疏松 Loose	20	20	40	5	19.5	32.1	1.0	12	9.00	一级 First grade
2	万州区 Wanzhou District	疏松 Loose	22	23	45	5	10.0	27.6	0.7	10	6.75	二级 Secondary grade
3	万州区 Wanzhou District	疏松 Loose	20	30	50	10	9.7	16.3	0.9	3	5.25	三级 Third grade
4	万州区 Wanzhou District	疏松 Loose	15	5	20	15	7.0	19.9	0.4	10	4.50	四级 Fourth grade
5	万州区 Wanzhou District	疏松 Loose	20	0	20	25	9.9	18.9	0.8	3	4.50	五级 Fifth grade
6	云阳县 Yunyang Country	疏松 Loose	25	15	40	6	14.6	31.8	0.9	9	9.75	一级 First grade
7	云阳县 Yunyang Country	疏松 Loose	25	25	50	7	9.0	21.1	0.6	7	9.25	二级 Secondary grade
8	云阳县 Yunyang Country	较紧实 Relatively compact	24	16	40	12	19.9	22.4	1.4	6	8.00	三级 Third grade
9	云阳县 Yunyang Country	疏松 Loose	20	20	40	16	12.3	24.8	0.7	4	6.50	四级 Fourth grade
10	云阳县 Yunyang Country	松散 Unconsolidated	20	0	20	20	5.3	28.4	0.4	4	5.25	五级 Fifth grade
11	北碚区 Beibei District	疏松 Loose	20	15	35	5	12.4	28.4	0.9	18	9.00	一级 First grade
12	北碚区 Beibei District	疏松 Loose	19	21	40	5	12.9	24.7	1.0	6	7.88	二级 Secondary grade
13	北碚区 Beibei District	疏松 Loose	20	10	30	10	16.6	17.4	1.1	45	7.13	三级 Third grade
14	北碚区 Beibei District	疏松 Loose	25	0	25	15	10.0	20.8	0.6	1	6.38	四级 Fourth grade
15	北碚区 Beibei District	疏松 Loose	15	0	15	25	10.6	28.8	0.7	6	5.63	五级 Fifth grade
16	綦江区 Qijiang District	疏松 Loose	20	20	40	5	12.2	12.9	0.8	29	9.30	一级 First grade
17	綦江区 Qijiang District	较疏松 Relatively loose	20	20	40	12	14.4	22.6	1.3	6	6.00	二级 Secondary grade
18	綦江区 Qijiang District	疏松 Loose	20	15	35	10	16.9	18.3	1.1	104	5.25	三级 Third grade
19	綦江区 Qijiang District	疏松 Loose	25	15	40	11.5	16.8	12.7	0.6	19	4.50	四级 Fourth grade
20	綦江区 Qijiang District	疏松 Loose	20	0	20	25	18.7	0.1	1.0	139	4.12	五级 Fifth grade
21	江津区 Jiangjin District	疏松 Loose	15	15	30	5	14.0	28.6	1.2	2	6.38	一级 First grade
22	江津区 Jiangjin District	疏松 Loose	19	21	40	5	12.9	21.5	1.0	6	6.00	二级 Secondary grade
23	江津区 Jiangjin District	疏松 Loose	20	20	40	10	10.5	15.8	0.8	1	5.25	三级 Third grade
24	江津区 Jiangjin District	疏松 Loose	20	10	30	15	21.1	16.6	1.1	14	4.50	四级 Fourth grade
25	江津区 Jiangjin District	疏松 Loose	20	10	30	15	16.3	14.1	1.2	0	4.13	五级 Fifth grade
26	彭水县 Pengshui County	疏松 Loose	20	25	45	5	19.6	11.5	1.3	4	9.75	一级 First grade
27	彭水县 Pengshui County	疏松 Loose	20	20	40	7	15.6	12.2	1.0	27	9.10	二级 Secondary grade
28	彭水县 Pengshui County	疏松 Loose	20	10	30	14	14.0	16.5	1.1	8	7.75	三级 Third grade
29	彭水县 Pengshui County	疏松 Loose	20	0	20	16	9.6	25.4	1.2	9	6.00	四级 Fourth grade
30	彭水县 Pengshui County	较紧实 Relatively compact	20	0	20	22	23.4	10.4	1.5	4	5.55	五级 Fifth grade
31	巴南区 Banan District	较疏松 Relatively loose	20	10	30	5	22.8	13.0	1.3	51	9.75	一级 First grade
32	巴南区 Banan District	较疏松 Relatively loose	20	20	40	7	15.5	25.8	1.0	8	8.10	二级 Secondary grade
33	巴南区 Banan District	疏松 Loose	15	10	25	14	32.3	12.7	1.5	27	5.50	三级 Third grade
34	巴南区 Banan District	疏松 Loose	20	0	20	17	14.8	-	1.0	14	6.00	四级 Fourth grade
35	巴南区 Banan District	疏松 Loose	20	0	20	17	12.6	17.3	0.8	18	5.55	五级 Fifth grade

表1

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参考文献 33

[1]	张怡, 何丙辉, 王仁新, 郭志敏, 唐柄哲 . 横坡和顺坡耕作对紫色土土壤团聚体稳定性的影响. 中国生态农业学报, 2013,21(2):192-198.
	ZHANG Y, HE B H, WANG R X, GUO Z M, TANG B Z . Effects of across- and along-slope ploughs on soil aggregate stability. Chinese Journal of Eco-Agriculture, 2013,21(2):192-198. (in Chinese)
[2]	朱波, 况福虹, 高美荣, 汪涛, 王小国, 唐家良 . 土层厚度对紫色土坡地生产力的影响. 山地学报, 2009,29(6):735-739.
	ZHU B, KUANG F H, GAO M R, WANG T, WANG X G, TANG J L . Effects of soil thickness on productivity of sloping cropland of purple soil. Journal of Mountain Science, 2009,29(6):735-739. (in Chinese)
[3]	史东梅 . 基于RUSLE模型的紫色丘陵区坡耕地水土保持研究. 水土保持学报, 2010,24(3):39-44.
	SHI D M . Soil and water conservation on cultivated slope land in purple hilly area based on RUSLE model. Journal of Soil and Water Conservation, 2010,24(3):39-44. (in Chinese)
[4]	金慧芳, 史东梅, 陈正发, 刘益军, 娄义宝, 杨旭 . 基于聚类及PCA分析的红壤坡耕地耕层土壤质量评价指标. 农业工程学报, 2018,34(7):155-164.
	JIN H F, SHI D M, CHEN Z F, LIU Y J, LOU Y B, YANG X . Evaluation indicators of cultivated layer soil quality for red soil slope farmland based on cluster and PCA analysis. Transactions of the Chinese Society of Agricultural Engineering, 2018,34(7):155-164. (in Chinese)
[5]	丁文斌, 蒋光毅, 史东梅, 刘益军, 蒋平, 常松果 . 紫色土坡耕地土壤属性差异对耕层土壤质量的影响. 生态学报, 2017(19):195-208.
	DING W B, JIANG G Y, SHI D M, LIU Y J, JIANG P, CHANG S G . Effect of different soil properties on plow-layer soil quality of sloping farmland in purple hilly areas.Acta Ecologica Sinica, 2017(19):195-208. (in Chinese)
[6]	REZAEI S A, GILKES R J, ANDREWS S S . A minimum data set for assessing soil quality in rangelands. Geoderma, 2006,136(1/2):229-234.
[7]	SEKER C, OZAYTEKIN H H, NEGIŞ H , GÜMÜŞ İLKNUR, DEDEOGLU M, ATMACA E, KARACA Ü. Identification of regional soil quality factors and indicators: A case study on an alluvial plain (central Turkey). Solid Earth, 2017,8(3):1-33.
[8]	闫建梅, 何丙辉, 田太强 . 不同施肥与耕作对紫色土坡耕地土壤侵蚀及氮素流失的影响. 中国农业科学, 2014,47(20):4027-4035.
	YAN J M, HE B H, TIAN T Q . Effect of fertilizer levels and tillage methods on soil erosion and nutrient loss in purple soil area. Scientia Agricultura Sinica, 2014, 47(20):4027-4035. (in Chinese)
[9]	LIN C, TU S, HUANG J, CHEN Y . The effect of plant hedgerows on the spatial distribution of soil erosion and soil fertility on sloping farmland in the purple-soil area of China. Soil & Tillage Research, 2009,105(2):307-312.
[10]	张贝尔, 黄标, 赵永存, 孙维侠, 胡文友, 张晓光 . 华北平原典型区土壤肥力低下区识别及限制因子分析. 土壤学报, 2012,49(5):841-849.
	ZHANG B E, HUANG B, ZHAO Y C, SUN W X, HU W Y, ZHANG X G . Identification of areas low in soil fertility and analysis of their limiting factors in the region typical of the north China plain. Acta Pedologica Sinica, 2012,49(5):841-849. (in Chinese)
[11]	张立江, 汪景宽, 裴久渤, 李双异, 安婷婷 . 东北典型黑土区耕地地力评价与障碍因素诊断. 中国农业资源与区划, 2017,38(1):110-117.
	ZHANG L J, WANG J K, PEI J B, LI S Y, AN T T . Evaluation of cultivated land fertility and its obstacle factores diagnosis in the typical black soil area of northeast China. Chinese Journal of Agricultural Resources and Regional Planning, 2017,38(1):110-117. (in Chinese)
[12]	樊亚男, 姚利鹏, 瞿明凯, 胡文友, 黄标, 赵永存 . 基于产量的稻田肥力质量评价及障碍因子区划——以进贤县为例. 土壤学报, 2017,54(5):1157-1169.
	FAN Y N, YAO L P, QU M K, HU W Y, HUANG B, ZHAO Y C . Yield-based soil fertility quality assessment and constraint factor- based zoning of paddy soil-A case study of Jinxian county. Acta Pedologica Sinica, 2017,54(5):1157-1169. (in Chinese)
[13]	匡丽花, 叶英聪, 赵小敏, 郭熙 . 基于改进TOPSIS方法的耕地系统安全评价及障碍因子诊断. 自然资源学报, 2018,33(9):1627-1641.
	KUANG L H, YE Y C, ZHAO X M, GUO X . Evaluation and obstacle factor diagnosis of cultivated land system security in Yingtan city based on the improved TOPSIS method. Journal of Natural Resources, 2018,33(9):1627-1641. (in Chinese)
[14]	史东梅, 蒋光毅, 蒋平, 娄义宝, 丁文斌, 金慧芳 . 土壤侵蚀因素对紫色丘陵区坡耕地耕层质量影响. 农业工程学报, 2017,33(13):270-279.
	SHI D M, JIANG G Y, JIANG P, LOU Y B, DING W B, JIN H F . Effects of soil erosion factors on cultivated-layer quality of slope farmland in purple hilly area. Transactions of the Chinese Society of Agricultural Engineering, 2017,33(13):270-279. (in Chinese)
[15]	李伟 . 重庆耕地地力研究与评价(一)(二)(三). 北京: 中国农业出版社, 2012.
	LI W. Research and Evaluation of Cultivated Land Fertility in Chongqing (I) (II) (III). Beijing: China Agriculture Press, 2012. (in Chinese)
[16]	秦伟霞, 王新闯, 马守臣, 张合兵, 陈宁丽, 宋香平 . 基于功能分区的土地生态质量障碍因子诊断——以新乡市为例. 水土保持研究, 2015,22(4):148-154.
	QIN W X, WANG X C, MA S C, ZHANG H B, CHEN N L, SONG X P . Obstacle factors diagnosis of land ecological quality based on functional partition-A case study of Xinxiang city. Research of Soil and Water Conservation, 2015,22(4):148-154. (in Chinese)
[17]	史德明, 韦启潘, 梁音, 杨艳生, 吕喜玺 . 中国南方侵蚀土壤退化指标体系研究. 水土保持学报, 2000(3):1-9.
	SHI D M, WEI Q P, LIANG Y, YANG Y S, LV X X . Study on degradation index system of eroded soils in southern China.Journal of Soil and Water Conservation, 2000(3):1-9. (in Chinese)
[18]	韩晓增, 邹文秀, 陆欣春, 段景海 . 旱作土壤耕层及其肥力培育途径. 土壤与作物, 2015,4(4):145-150.
	HAN X Z, ZOU W X, LU X C, DUAN J H . The soil cultivated layer in dryland and technical patterns in cultivating soil fertility. Soil and Crop, 2015,4(4):145-150. (in Chinese)
[19]	刘海涛, 姚莉, 朱永群, 王宏, 许文志, 王谢, 林超文 . 深松和秸秆覆盖条件下紫色土坡耕地水分养分流失特征. 水土保持学报, 2018,32(6):52-57, 165.
	LIU H T, YAO L, ZHU Y Q, WANG H, XU W Z, WANG X, LIN C W . Characteristics of water and nutrients loss under subsoiling and straw mulching in purple soil slope cropland. Journal of Soil and Water Conservation, 2018,32(6):52-57, 165. (in Chinese)
[20]	董杰, 段艺芳, 许玉凤, 杨达源, 周彬 . 三峡库区紫色土坡地土壤退化程度评价及驱动机制. 水土保持通报, 2009,29(4):51-56.
	DONG J, DUAN Y F, XU Y F, YANG D Y, ZHOU B . Evaluation and driving mechanism of land degradation in a sloping field of purple soil in three gorges reservoir area. Bulletin of Soil and Water Conservation, 2009,29(4):51-56. (in Chinese)
[21]	ZHANG Q, LIU D, CHENG S, HUANG X . Combined effects of runoff and soil erodibility on available nitrogen losses from sloping farmland affected by agricultural practices. Agricultural Water Management, 2016,176:1-8.
[22]	ZHANG J H, LI F C . Soil redistribution and organic carbon accumulation under long-term (29 years) upslope tillage systems. Soil Use and Management, 2013,29(3):365-373.
[23]	LUO J, ZHENG Z, LI T, HE S . Spatial heterogeneity of microtopography and its influence on the flow convergence of slopes under different rainfall patterns. Journal of Hydrology, 2017,545:88-99.
[24]	白伟, 孙占祥, 郑家明, 郝卫平, 刘勤, 刘洋, 冯良山, 蔡倩 . 虚实并存耕层提高春玉米产量和水分利用效率. 农业工程学报, 2014,30(21):81-90.
	BAI W, SUN Z X, ZHENG J M, HAO W P, LIU Q, LIU Y, FENG L S, CAI Q . Furrow loose and ridge compaction plough layer improves spring maize yield and water use efficiency. Transactions of the Chinese Society of Agricultural Engineering, 2014,30(21):81-90. (in Chinese)
[25]	李富程, 花小叶, 王彬 . 紫色土坡地旋耕机耕作侵蚀特征. 中国水土保持科学, 2016,14(1):71-78.
	LI F C, HUA X Y, WANG B . Rate and pattern of tillage erosion by rotary cultivator on the steep land of purple soil. Journal of Soil and Water Conservation, 2016, 14(1):71-78. (in Chinese)
[26]	ZHAO P, LI S, WANG E, CHEN X, DENG J . Tillage erosion and its effect on spatial variations of soil organic carbon in the black soil region of China. Soil and Tillage Research, 2018,178:72-81.
[27]	任雨之, 郑江坤, 付滟, 王文武, 曾倩婷, 向明辉, 陈鑫 . 不同耕种模式下遂宁组紫色土坡耕地产流产沙特征. 水土保持学报, 2019,33(2):30-38.
	REN Y Z, ZHENG J K, FU Y, WANG W W, ZENG Q T, XIANG M H, CHEN X . Characteristics of runoff and sediment yield in purple soil sloping farmland under different tillage patterns in Suining formation. Journal of Soil and Water Conservation, 2019, 33(2):30-38. (in Chinese)
[28]	朱波, 陈实, 游祥, 彭奎, 张先婉 . 紫色土退化旱地的肥力恢复与重建. 土壤学报, 2002(5):743-749.
	ZHU B, CHEN S, YOU X, PENG K, ZHANG X W . Soil fertility restoration on degraded upland of purple soil.Acta Pedologica Sinica, 2002(5):743-749. (in Chinese)
[29]	苏正安, 熊东红, 张建辉, 董一帆, 杨超, 张小波, 鲜纪绅 . 紫色土坡耕地土壤侵蚀及其防治措施研究进展. 中国水土保持, 2018(2):42-47, 69.
	SU Z A, XIONG D H, ZHANG J H, DONG Y F, YANG C, ZHANG X B, XIAN J S . Research progress of soil erosion of purple soil slope farmland and its prevention and control measures.Soil and Water Conservation in China, 2018(2):42-47, 69. (in Chinese)
[30]	王亚男, 徐梦洁, 申燕, 黄化刚, 陈雪, 庄舜尧 . 毕节市土壤耕作层厚度的空间变异特征. 贵州农业科学, 2018,46(10):81-84.
	WANG Y N, XU M J, SHEN Y, HUANG H G, CHEN X, ZHUANG S Y . Spatial variation characteristics of soil tillage layer thickness in Bijie city. Guizhou Agricultural Sciences, 2018, 46(10):81-84. (in Chinese)
[31]	黄少燕, 查轩 . 坡耕地侵蚀过程与土壤理化特性演变. 山地学报, 2002(3):290-295.
	HUANG S Y, ZHA X . Study on soil erosion process and evolution of soil physicochemisty characteristics on sloping farmland. Journal of Mountain Science, 2002(3):290-295. (in Chinese)
[32]	ZHANG J, QUINE T A, SHIJUN N I, FANGLONG G E . Stocks and dynamics of SOC in relation to soil redistribution by water and tillage erosion. Global Change Biology, 2006,12(10):1834-1841.
[33]	ZHANG Q, CHEN S, DONG Y, LIU D, YANG X, YANG Z . Controllability of phosphorus losses in surface runoff from sloping farmland treated by agricultural practices. Land Degradation & Development, 2017,28(5):1704-1716.

指标 Index	土壤属性指标对作物产量的作用 Effect of soil attribute index for crop yield	隶属函数 Membership function	土层 Soil layer	隶属函数参数 Membership function parameter		权重 Weight
指标 Index		隶属函数 Membership function	土层 Soil layer	a （下限Lower limit）	b （上限Up limit）	权重 Weight
土壤有机质 Soil organic matter (g·kg^-1)	+		耕作层 Topsoil layer	5.29	32.30	0.186
			心土层 Subsoil layer	5.07	21.40	0.217
			底土层 Bottom soil	3.57	16.60	0.155
土壤全氮 Soil total nitrogen (g·kg^-1)	+		耕作层 Topsoil layer	0.41	1.54	0.184
			心土层 Subsoil layer	0.35	1.08	0.183
			底土层 Bottom soil	0.27	2.13	0.252
土壤有效磷 Soil available phosphorus (mg·kg^-1)	+		耕作层 Topsoil layer	1.20	139.00	0.128
			心土层 Subsoil layer	0.09	22.00	0.137
			底土层 Bottom soil	0.19	123.00	0.208
阳离子交换量 Cation exchange capacity (cmol(+)·L^-1)	+		耕作层 Topsoil layer	0.08	32.10	0.155
			心土层 Subsoil layer	5.38	38.70	0.140
			底土层 Bottom soil	0.11	25.40	0.182
耕作层厚度 Topsoil layer thickness (cm)	+		耕作层 Topsoil layer	15.00	25.00	0.188
			心土层 Subsoil layer	-	-	-
			底土层 Bottom soil	-	-	-
心土层厚度 Subsoil layer thickness (cm)	+		耕作层 Topsoil layer	-	-	-
			心土层 Subsoil layer	5.00	30.00	0.130
			底土层 Bottom soil	-	-	-
田面坡度 Field surface slope (°)	-		耕作层 Topsoil layer	5.00	25.00	0.158
			心土层 Subsoil layer	5.00	16.00	0.193
			底土层 Bottom soil	5.00	25.00	0.203

地力等级 Productivity grade of cultivated land	土层 Soil layer	土壤属性指标障碍度 Barrier degree of soil property index (%)
地力等级 Productivity grade of cultivated land	土层 Soil layer	土壤有机质 Soil organic matter	土壤全氮 Soil total nitrogen	土壤有效磷 Soil available phosphorus	阳离子交换量 Cation exchange capacity	土层厚度 Soil thickness	田面坡度 Field surface slope
一级 First	耕作层 Topsoil layer	22.32	16.42	23.10	9.41	19.16	0.19
	心土层 Subsoil layer	29.41	19.21	21.11	15.69	14.15	0.43
	底土层 Bottom soil	17.82	30.82	37.53	13.56	-	0.27
二级 Secondary	耕作层 Topsoil layer	24.71	18.22	22.26	8.87	14.86	2.22
	心土层 Subsoil layer	31.66	17.54	20.75	14.96	9.48	5.61
	底土层 Bottom soil	19.92	37.09	35.55	4.11	-	3.33
三级 Third	耕作层 Topsoil layer	18.69	12.28	18.59	13.05	17.24	7.10
	心土层 Subsoil layer	24.18	14.52	17.21	16.79	12.48	14.81
	底土层 Bottom soil	15.45	31.50	31.75	11.45	-	9.84
四级 Fourth	耕作层 Topsoil layer	20.09	17.71	18.26	11.00	12.20	9.74
	心土层 Subsoil layer	20.28	14.85	13.69	12.91	17.51	20.77
	底土层 Bottom soil	15.49	31.89	30.38	7.17	-	15.07
五级 Fifth	耕作层 Topsoil layer	18.21	14.56	15.26	10.59	15.33	15.46
	心土层 Subsoil layer	-	-	-	-	-	-
	底土层 Bottom soil	3.06	28.28	17.65	21.99	-	29.02