琼中黎母山-湾岭地区土壤硒、碘分布特征及其影响因素探讨

龚晶晶; 高健翁; 杨剑洲; 吴慧; 唐世新; 马生明

doi:10.19509/j.cnki.dzkq.2021.0625

琼中黎母山-湾岭地区土壤硒、碘分布特征及其影响因素探讨

doi: 10.19509/j.cnki.dzkq.2021.0625

龚晶晶^{1, 2,},
高健翁^{1, 2},
杨剑洲^{1, 2},
吴慧^{1, 2, ,},
唐世新^{1, 2},
马生明^{1, 2}

基金项目:

中国地质调查局地质调查项目 DD20190305

详细信息

作者简介:
龚晶晶(1989-), 男, 工程师, 主要从事生态地质研究工作。E-mail: gjingjing@cgs.gov.cn

通讯作者:
吴慧(1988-), 女, 工程师, 主要从事矿床地球化学研究工作。E-mail: wuhui@cgs.gov.cn

中图分类号: X53
计量
- 文章访问数: 476
- PDF下载量: 190
- 被引次数: 0
出版历程
- 收稿日期: 2021-01-05

Distribution and influencing factors of soil selenium and iodine in Limushan-Wanling, Qiongzhong area

Gong Jingjing^{1, 2
,},
Gao Jianweng^{1, 2},
Yang Jianzhou^{1, 2},
Wu Hui^{1, 2
, ,},
Tang Shixin^{1, 2},
Ma Shengming^{1, 2}

摘要

摘要: 琼中黎母山-湾岭地区位于海南岛中部，调查发现该地区土壤同时具有富硒、富碘的特征。以研究区表层（0~20 cm）、中层（80~100 cm）、深层（180~200 cm）土壤样品分析结果为基础，探讨了土壤硒、碘的分布特征及其影响因素。结果显示，表层土壤中Se、I质量分数具有高正相关性，并与高程为正相关关系，结合已有研究成果，推断在研究区范围内降雨作用是研究区表层土壤Se、I质量分数空间分布格局的关键影响因素。通过分析表层、中层、深层土壤Se、I质量分数与土壤pH值、总有机碳（TOC）、Al₂O₃、Fe₂O₃质量分数的相关关系和变化规律，总结了研究区Se、I在土壤垂向剖面上的赋存、迁移规律。这些结果可为当地优质土地资源的高效利用提供科学依据，也可为土壤Se来源、迁移研究提供新的证据。
- 琼中 /
- 土壤 /
- 硒 /
- 碘 /
- 降雨
Abstract: Qiongzhong Limushan-Wanling area is located in the middle of Hainan Island, where has an abundance of selenium-rich and iodine-rich soil resources.The distribution characteristics of Se and I contents were analyzed based on the analysis results of soil samples in the topsoil (0-20 cm), middle-layer-soil(80-100 cm), and deep-soil (180-200 cm) of the study area.The correlation characteristics of Se and I in soil and their relationship with elevation potentially indicate that the input of rainfall to soil Se and I is a key factor leading to the enrichment of Se and I.By analyzing the correlation and change law between the contents of Se, I and the contents of pH, soil organic matter, Al₂O₃ and Fe₂O₃ in top, middle and deep layer soil, the enrichment and migration of Se and I in the vertical section of soil in the study area was summarized.These results can provide scientific basis for the efficient use of local high-quality land resources and provide new evidence for the study of soil Se source and migration.
- Qiongzhong area /
- soil /
- Se /
- I /
- precipitation

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图 1 研究区地质简图和采样点位置示意图

Figure 1. Geological skematic maps and sampling location

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图 2 琼中县平均降雨量图(a)和土壤发生类型图(b)

注: 海拔数据来源于国家科技基础条件平台—国家地球系统科学数据中心，土壤发生类型数据来源于《中华人民共和国多目标区域地球化学图集(海南岛)》

Figure 2. Maps of annual rainfall (a) and soil type (b) of Qiongzhong County

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图 3 研究区表层(a, b)-中层(c, d)-深层(e, f)土壤Se、I质量分数分布图

γπK.中白垩世花岗斑岩；ηγJ₃.晚侏罗世二长花岗岩；γδP₁.早二叠世花岗闪长岩；δK₁.早白垩世闪长岩；γδK₁.早白垩世黑云花岗闪长岩；ηγK₁.早白垩世二长花岗岩；ξγJ₃.晚侏罗世正长花岗岩；ηγT₂.中三叠世二长花岗岩；ξγT₂.中三叠世正长花岗岩；ηγP₂.中二叠世二长花岗岩；ξγP₂.中二叠世正长花岗岩；Pt₂g.戈枕村组黑云斜长片麻岩；Pt₂^1-2e.峨文岭组石英云母片岩；l.细晶岩脉

Figure 3. Se and I content distribution in the top (a, b), middle (c, d) and deep (e, f) soil of the study area

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图 4 不同成壤母岩形成的土壤Se、I平均质量分数柱状图(地质体代号同图 3)

Figure 4. Bar graph of soil selenium and iodine contents by different soil parent rocks

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图 5 不同深度土壤Se、I质量分数与高程散点图

r为皮尔逊相关系数；n为样品数量；p为皮尔逊相关显著性检验值

Figure 5. Scatter plots of soil selenium, iodine contents at different depths and elevation

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图 6 不同土壤类型不同深度土壤I-Se质量分数散点图

Figure 6. Scatter plots of soil Se and I contents at different depths in various soil types

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图 7 不同土壤类型不同深度土壤Se、I与pH值质量分数散点图

Figure 7. Scatter plots of soil Se, I contents and pH at different depths in various soil types

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图 8 不同土壤类型不同深度土壤Se、I质量分数与TOC质量分数散点图

Figure 8. Scatter plots of soil Se, I and TOC contents at different depths in various soil types

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图 9 不同土壤类型不同深度土壤Se、I质量分数与Fe₂O₃质量分数散点图

Figure 9. Scatter plots of soil Se, I and Fe₂O₃ contents at different depths in various soil types

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图 10 不同土壤类型不同深度土壤Se、I质量分数与土壤Al₂O₃质量分数散点图

Figure 10. Scatter plots of soil Se, I and Al₂O₃ contents at different depths in various soil types

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表 1 各指标分析方法及检出限

Table 1. Analytical methods and detection limits of various indicators

指标	分析方法	检出限	单位
Se	AFS	0.010 0	mg/kg
I	COL	0.350 0	mg/kg
pH	ISE	0.100 0	无量纲
TOC	VOL	0.030 0	%
Hg	AFS	0.000 5	mg/kg
Al₂O₃	XRF	0.050 0	%
Fe₂O₃	ICP-AES	0.050 0	%

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表 2 研究区土壤Se、I丰缺划分界线及特征

Table 2. Abundance and deficiency demarcation value of soil selenium and iodine

全量w(Se)/ (mg·kg^-1)	硒效应	样品数(占比/%)			全量w(I)/ (mg·kg^-1)	碘效应	样品数(占比/%)
全量w(Se)/ (mg·kg^-1)	硒效应	表层	中层	深层	全量w(I)/ (mg·kg^-1)	碘效应	表层	中层	深层
< 0.125	硒不足	20(6.6)	57(18.8)	113(37.2)	< 1	碘不足	40(13.2)	67(22.0)	100(32.9)
[0.125, 0.175)	硒潜在不足	11(3.6)	37(12.2)	37(12.2)	[1, 1.5)	碘潜在不足	27(8.9)	23(7.6)	34(11.2)
[0.175, 0.4)	足硒	140(46.1)	127(41.8)	114(37.5)	[1.5, 5)	足碘	80(26.3)	106(34.9)	120(39.5)
[0.4, 3)	富硒	133(43.8)	83(27.3)	40(13.2)	[5, 100)	富碘	157(51.6)	108(35.5)	50(16.4)
≥3	硒中毒	0	0	0	≥100	碘中毒	0	0	0

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表 3 不同成壤母岩形成的土壤Se、I平均质量分数

Table 3. Comparison of soil selenium and iodine contents by different soil parent rocks

地质体	数量/ 个	w(Se)/(mg·kg^-1)				w(I)/(mg·kg^-1)
地质体	数量/ 个	表层	中层	深层	表层/深层	表层	中层	深层	表层/深层
ξγT₂	18	0.39	0.27	0.18	2.17	5.61	4.04	2.67	2.10
ξγJ₃	22	0.37	0.30	0.21	1.78	5.65	4.93	3.34	1.69
ηγT₂	129	0.44	0.34	0.24	1.86	6.51	5.24	3.14	2.07
ηγP₂	30	0.40	0.30	0.21	1.89	5.92	4.15	2.67	2.21
ηγJ₃	23	0.35	0.23	0.18	1.89	5.28	3.57	3.26	1.62
γπK₂	10	0.50	0.27	0.22	2.23	6.05	2.68	2.06	2.93
δK₁	8	0.39	0.28	0.19	2.05	6.65	5.12	3.56	1.87
γδK₁	45	0.37	0.31	0.22	1.69	4.46	3.61	2.24	2.00
Pt₂g	9	0.41	0.43	0.26	1.58	6.03	6.52	3.58	1.60
注：地质体代号同图 1

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表 4 不同土壤发生类型中Se、I质量分数与其他指标相关性

Table 4. Correlation between soil selenium, iodine contents and other indicators in various soil types

其他指标	砖红壤(n=274)						水稻土(n=30)
	表层		中层		深层		表层		中层		深层
	Se	I	Se	I	Se	I	Se	I	Se	I	Se	I
Se		0.855^**		0.781^**		0.720^**		0.647^**		-0.042		-0.052
I	0.855^**		0.781^**		0.720^**		0.647^**		-0.042		-0.052
pH	-0.556^**	-0.476^**	-0.448^**	-0.353^**	-0.404^**	-0.327^**	-0.362^*	-0.163	-0.281^*	0.235	-0.389^*	0.242
TOC	0.350^**	0.177^**	0.323^**	0.194^**	0.307^**	0.145^**	0.513^**	0.333^*	0.643^**	0.027	0.737^**	0.005
Fe₂O₃	0.281^**	0.330^**	0.176^**	0.369^**	0.172^**	0.420^**	0.491^**	0.411^*	0.327	0.244	0.074	0.247
Al₂O₃	0.470^**	0.480^**	0.329^**	0.432^**	0.302^**	0.436^**	0.410^*	0.346	0.017	0.203	-0.161	0.265
Hg	0.499^**	0.312^**	0.488^**	0.407^**	0.753^**	0.595^**	0.600^**	0.311	0.682^**	0.046	0.721^**	0.078
注：n为样品数量；*表示在0.01级别相关性显著；表示在0.05级别相关性显著；统计过程中，删除了表层砖红壤TOC离群数据点1个，删除了表层、中层砖红壤Hg离群数据点各4个

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表 5 高程与土壤中Se、I、TOC质量分数以及pH值的相关性

Table 5. Correlation between elevation and soil selenium, iodine contents, TOC, pH

	高程-Se质量分数		高程-I质量分数		高程-TOC质量分数		高程-pH值
	相关系数	P	相关系数	P	相关系数	P	相关系数	P
表层	0.302	< 0.01	0.309	< 0.01	0.086	0.135	-0.146	0.011 < 0.05
中层	0.105	0.069	0.087	0.129	0.058	0.312	-0.116	0.043 < 0.05
深层	0.040	0.492	0.065	0.257	0.005	0.925	-0.134	0.020 < 0.05

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表 6 不同类型岩石中Se的质量分数

Table 6. Selenium contents in various rock types

岩石	w(Se)/(mg·kg^-1)	数据来源
中国酸性岩	0.033	文献[23]
中国中性岩	0.058	文献[23]
中国东部片岩	0.100	文献[24]
中国东部斜长片麻岩	0.070	文献[24]
琼中县中酸性岩	0.060	(N=77，中位数，尚未发表数据)
琼中县变质岩	0.180	(N=5，中位数，尚未发表数据)

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表 7 不同高程范围内样品土壤发生类型分布

Table 7. Distribution of soil types in various elevation ranges

高程/m		[50, 100]	(100, 150]	(150, 200]	(200, 250]	(250, 300]	(300, 350]	(350, 400]	(400, 450]
水稻土	数量/个	1	3	11	3	7	4	1	0
水稻土	占比/%	50.0	15.8	15.9	3.2	8.3	16.0	11.1	0.0
砖红壤	数量/个	1	16	58	91	77	21	8	2
砖红壤	占比/%	50.0	84.2	84.1	96.8	91.7	84.0	88.9	100.0

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