Determination of Soil Fluorine Speciation and Main Factors Affecting Tea Fluorine Content in Tea Gardens of Daba Mountain
-
摘要:
氟在人体生长发育和骨骼代谢中起着重要作用，近年来通过饮茶摄入氟与人体健康的关系受到较大关注。本文以大巴山区紫阳县茶园土壤为研究对象，采集64组茶园土壤和对应茶叶样品，测定土壤理化性质、土壤氟形态、茶叶氟含量，通过多元回归分析建立了影响大巴山区茶叶氟含量的Freundlich模型，并检验了模型的预测精度。结果显示：①研究区茶园表层土壤氟含量范围为487.37～1120.78mg/kg，平均值为730.63mg/kg；研究区茶叶氟含量为31.23～112.49mg/kg，平均值为57.58mg/kg，所有样品均未超过农业标准(NY659—2003)限值；②研究区茶园土壤氟的形态分布为：残渣态＞水溶态＞有机态＞铁锰结合态＞可交换态，水溶态氟含量范围为5.27～23.15mg/kg，平均值为9.72mg/kg，远高于中国地氟病发生区水溶态氟的平均含量2.5mg/kg，说明研究区存在一定生态风险。土壤水溶态氟与茶叶氟含量有显著相关性(n=64，r=0.82，p＜0.01)，其余形态与茶叶氟含量无显著相关性；③以水溶态氟、CEC、交换性铝、有机质、pH五个因子为变量，构建了影响茶叶氟含量的多元回归方程，采用Freundlich模型预测茶叶氟含量，该模型可以解释86.0%的变异，通过验证模型的预测精度达到88.0%，总体来说预测效果较好。本研究结合土壤理化性质、土壤氟形态数据构建了预测茶叶氟的模型，并达到可靠程度，可以为紫阳地区及相似地区茶叶氟生态风险评价、指导绿色农业发展提供理论依据。
Abstract:In recent years, the relationship between fluorine intake through tea drinking and human health has received significant attention. To investigate the effect of soil properties on tea fluorine, 64 sets of tea garden soil-tea samples were collected in Ziyang County, Daba Mountain area, and a Freundlich model that affects the fluorine content of tea was established. The results show that: (1) The fluorine content in the surface soil of tea gardens ranges from 487.37 to 1120.78mg/kg, with an average value of 730.63mg/kg; The fluorine content of tea is 31.23-112.49mg/kg, with an average value of 57.58mg/kg. All samples do not exceed the limit of agricultural standards (NY659—2003); (2) The distribution of fluorine speciation in the soil is as follows: residual state>water-soluble state>organic state>iron manganese bound state>exchangeable state; (3) A multiple regression equation affecting the fluorine content in tea was constructed using five factors: water-soluble fluorine, CEC, exchangeable aluminum, organic matter, and pH as variables. The model can explain 86.0% of the variation, and the prediction accuracy of the model reached 88.0% through validation. This study can provide theoretical basis for the development of green agriculture. The BRIEF REPORT is available for this paper at
http://www.ykcs.ac.cn/en/article/doi/10.15898/j.ykcs.202307070089 .-
Key words:
- Ziyang area /
- soil fluorine /
- tea fluorine /
- soil fluorine speciation /
- multiple regression analysis
-
-
表 1 土壤氟形态提取步骤及检出限［15］
Table 1. The extraction procedure and detection limit of fluorine speciation in soil of Ziyang area
土壤氟形态 提取剂 操作步骤 检出限
(μg/kg)水溶态氟(Ws-F) 70℃亚沸水 振荡0.5h 0.10 可交换态氟(Ex-F) 1mol/L氯化镁(pH 7.0) 25℃振荡1h 0.10 铁锰结合态氟(Fe/Mn-F) 0.04mol/L盐酸羟胺溶于20%(V/V)的乙酸溶液 60℃振荡1h 0.50 有机态氟(Or-F) 用0.02mol/L硝酸+30%的双氧水处理后再加3.2mol/L乙酸铵溶液 25℃振荡0.5h 0.80 残渣态氟(Res-F) 残渣态氟为全氟含量与其他形态氟含量总和之差 / 0.80 注：“/”表示无具体操作，残渣态=总氟−(水溶态氟+可交换态氟+铁锰结合态氟+有机态氟）。 
下载: 导出CSV
表 2 分析方法质量监控
Table 2. Quality control of analysis method
测试项目 分析方法 检出限 准确度
(△lgC)RSD
(%)报出率
(%)茶叶氟 离子选择性电极 1.5mg/kg 0.06 6.01 100 土壤氟 离子选择性电极 2.5mg/kg 0.01 0.98 100 水溶态氟 离子选择性电极 1.0 mg/kg 0.15 6.45 100 有机质 容量法 4.0% 0.02 5.19 100 CEC 原子荧光光谱法 0.01mg/kg 0.01 5.41 100 pH 离子选择性电极 0.10mg/kg 0.04 1.64 100 交换性铝 电感耦合等离子体发射光谱法 0.05mg/kg 0.01 5.20 100 交换性钙 电感耦合等离子体发射光谱法 0.01mg/kg 0.04 4.75 100 交换性镁 电感耦合等离子体发射光谱法 0.01mg/kg 0.03 3.67 100 交换性钾 电感耦合等离子体发射光谱法 0.01mg/kg 0.05 5.23 100 交换性钠 电感耦合等离子体发射光谱法 0.01mg/kg 0.02 3.15 100 土壤黏粒 比重法 0.001% 0.01 0.58 100 铝氧化物 容量法 0.001% 0.01 3.45 100 锰氧化物 原子吸收分光光度法 0.002% 0.03 1.88 100
下载: 导出CSV
表 3 研究区茶叶氟含量及土壤理化性质
Table 3. Physicochemical properties of soils in tea garden and its tea fluorine content
测试项目 平均值(n=64) 最小值 最大值 标准偏差 变异系数 茶叶氟(mg/kg) 57.58 31.23 112.49 43.91 76.27 土壤氟(mg/kg) 730.63 487.37 1120.78 345.02 87.22 有机质(mg/kg) 20.49 16.77 38.92 11.97 58.40 CEC(cmol/kg) 15.73 12.36 22.52 5.29 33.63 pH 6.1 5.2 7.4 1.17 19.21 交换性铝(cmol/kg) 0.94 0.74 1.23 0.25 26.08 交换性钙(cmol/kg) 5.52 3.79 6.23 1.35 24.50 交换性镁(cmol/kg) 1.36 1.12 3.27 1.17 86.12 交换性钾(cmol/kg) 0.71 0.41 1.47 0.68 95.88 交换性钠(cmol/kg) 0.19 0.08 0.34 0.13 68.49 土壤黏粒(%) 19.15 14.47 27.46 6.52 34.04 铝氧化物(g/kg) 44.87 35.67 56.34 10.90 24.29 锰氧化物(g/kg) 0.84 0.56 1.59 0.52 61.53
下载: 导出CSV
表 4 研究区茶园土壤氟形态含量及质量控制
Table 4. Contents of fluorine speciation of soils in tea garden in Ziyang area and its recovery rate
样品编号 水溶态氟
Ws-F含量
(mg/kg)可交换态氟
Ex-F含量
(mg/kg)铁锰结合态氟
Fe/Mn-F含量
(mg/kg)有机态氟
Or-F含量
(mg/kg)残渣态氟
Res-F含量
(mg/kg)全氟
To-F含量
(mg/kg)总量/全量
回收率
(%)1 6.14 0.46 5.09 8.17 523.67 551.30 98.59 2 7.34 0.23 6.68 9.34 689.22 739.20 96.43 3 5.27 0.78 7.21 7.23 623.14 649.34 99.12 4 8.24 1.24 5.23 8.19 578.98 616.93 97.56 5 10.76 0.56 7.85 11.25 718.98 739.49 101.34 6 23.15 1.23 6.22 9.67 563.45 613.35 98.43 7 14.89 0.89 5.84 8.34 456.83 500.09 97.34 8 11.34 0.75 5.37 9.34 779.17 832.79 96.78 9 8.65 0.96 5.46 7.12 895.24 926.88 98.98 10 7.43 0.83 5.28 7.24 952.12 942.46 103.23 11 5.56 0.79 6.39 8.27 845.21 870.05 99.56 12 8.23 0.78 7.94 7.89 753.34 814.51 95.54 13 9.45 1.02 8.18 5.26 489.19 527.72 97.23 含量范围 5.27～23.15 0.23～1.24 5.09～8.18 5.26～11.25 456.83～952.12 500.09～942.46 95.54～103.23 平均值 9.72 0.81 6.36 8.25 682.19 717.24 98.61 GBW07915 6.93(6.8±0.8) 0.78 6.34 4.67 451.28 508(520±21) 92.32 GBW07916 2.03(1.9±0.3) 0.46 2.44 5.89 321.67 361(353±17) 92.10 GBW07935 21.0(24.0±5.0) 1.25 6.88 6.89 426.22 498(506±22) 92.82 注：括号内数据为标准物质推荐值。
下载: 导出CSV
表 5 土壤理化性质、茶叶氟与土壤氟形态的相关性
Table 5. Correlation among physicochemical properties of soil, tea fluorine and soil fluorine speciation
测试项目 水溶态 可交换态 铁锰结合态 有机态 残渣态 土壤氟 茶叶氟 0.82** 0.03 0.002 0.14 −0.097 0.17 土壤氟 0.53* 0.32 0.44* 0.21 0.68** 1.0 有机质 −0.27 −0.035 0.15 −0.12 −0.04 0.39 CEC 0.85** −0.23 0.23 −0.04 0.14 −0.067 pH 0.55* 0.11 0.13 0.22 0.32 0.25 交换性铝 −0.14 −0.22 −0.31 −0.32 0.07 0.065 交换性钙 0.67** −0.034 0.21 0.14 0.11 0.11 交换性镁 −0.12 −0.013 0.17 0.09 0.18 0.07 交换性钾 0.52* −0.16 0.11 0.11 0.08 0.13 交换性钠 −0.13 −0.19 0.09 0.12 0.15 0.07 土壤黏粒 −0.75** −0.087 −0.14 −0.21 0.09 0.14 铝氧化物 −0.66** −0.32 −0.33 −0.35 0.07 0.43* 锰氧化物 0.13 −0.52* −0.44* −0.37 −0.24 0.37 注：“*”表示在0.05水平上显著相关；“**”表示在0.01水平上显著相关。
下载: 导出CSV
表 6 土壤理化性质与茶叶氟的相关性
Table 6. Correlation of soil physicochemical properties with tea fluorine
土壤指标 茶叶氟(Tea-F) 土壤指标 茶叶氟(Tea-F) r 置信区间 r 置信区间 水溶态氟 0.77 0.99 交换性镁 0.09 − 有机质 −0.35 0.95 交换性钾 −0.10 − CEC 0.55 0.99 交换性钠 −0.05 − pH 0.53 0.99 土壤黏粒 −0.86 0.99 交换性铝 0.67 0.99 铝氧化物 0.07 − 交换性钙 0.11 − 锰氧化物 0.07 − 注：“—”表示无考察价值。
下载: 导出CSV
表 7 影响茶叶氟的回归模型
Table 7. Regression model of factors influencing tea fluorine
方程 回归方程 R2 P n 1 lgCTea-F=lgCx1+1.82 0.54 ＜0.01 30 2 lgCTea-F=lgCx1+0.18lgCx2+1.21 0.56 ＜0.05 30 3 lgCTea-F=lgCx1+0.12lgCx2−1.32lgCx4+1.34 0.77 ＜0.01 30 4 lgCTea-F=lgCx1+0.22lgCx2−1.12lgCx4+1.22lgCx3+1.51 0.82 ＜0.01 30 5 lgCTea-F=lgCx1+0.14lgCx2+1.29lgCx3+0.15Cx5+0.79 0.84 ＜0.01 30 6 lgCTea-F=lgCx1+0.18lgCx2−1.42lgCx4+1.06lgCx3+0.09Cx5+1.09 0.86 ＜0.01 30 7 lgCTea-F=lgCx1+0.12lgCx2−2.62lgCx4+0.96lgCx3+0.12Cx5−1.28lgCx6+2.49 0.81 ＜0.01 30 注：n为处理数。
下载: 导出CSV
-
[1] 郜红建, 刘腾腾, 张显晨, 等. 安徽茶园土壤氟在茶树体内的富集与转运特征[J]. 环境化学, 2011, 30(8): 1462−1467.
Gao H J, Liu T T, Zhang X C, et al. Bioaccumulation and translocation of fluoride from soil to different parts of tea plants in Anhui Province[J]. Environmental Chemistry, 2011, 30(8): 1462−1467.
[2] He L L, Tu C L, He S Y, et al. Fluorine enrichment of vegetables and soil around an abandoned aluminium plant and its risk to human health[J]. Environmental Geochemistry and Health, 2021, 43: 1137−1154. doi: 10.1007/s10653-020-00568-5
[3] Jianmin B, Yu W, Juan Z. Arsenic and fluorine in groundwater in western Jilin Province, China: Occurrence and health risk assessment[J]. Natural Hazards, 2015(77): 1903−1914.
[4] Mukherjee I, Singh U K. Exploring a variance decomposition approach integrated with the Monte Carlo method to evaluate groundwater fluoride exposure on the residents of a typical fluorosis endemic semi-arid tract of India[J]. Environmental Research, 2022, 203: 111697. doi: 10.1016/j.envres.2021.111697
[5] 李凤嫣, 蒋天宇, 余涛, 等. 环境中氟的来源及健康风险评估研究进展[J]. 岩矿测试, 2021, 40(6): 793−807.
Li F Y, Jiang T Y, Yu T, et al. Review on sources of fluorine in the environment and health risk assessment[J]. Rock and Mineral Analysis, 2021, 40(6): 793−807.
[6] 邰苏日嘎拉, 李永春, 周文辉, 等. 宁夏固原市原州区高氟地区氟对人体健康的影响[J]. 岩矿测试, 2021, 40(6): 919−929.
Tai Surigala, Li Y C, Zhou W H, et al. Effect of fluorine on human health in high-fluorine areas in Yuanzhou district, Guyuan City, Ningxia Autonomous Region[J]. Rock and Mineral Analysis, 2021, 40(6): 919−929.
[7] Long H, Jiang Y M, Li C Q, et al. Effect of urea feeding on transforming and migrating soil fluorine in a tea garden of hilly region[J]. Environmental Geochemistry and Health, 2021, 43: 5087−5098. doi: 10.1007/s10653-021-00949-4
[8] 邢安琪, 武子辰, 徐晓寒, 等. 茶树富集氟的特点及其机制的研究进展[J]. 茶叶科学, 2022, 42(3): 301−315.
Xing A Q, Wu Z C, Xu X H, et al. Research advances of fluoride accumulation mechanisms in tea plant[J]. Journal of Tea Science, 2022, 42(3): 301−315.
[9] Ruan J Y, Ma L F, Shi Y Z, et al. The impact of pH and calcium on the uptake of fluoride by tea plant (Camellia sinensis)[J]. Annals of Botany, 2004, 93(1): 97−105. doi: 10.1093/aob/mch010
[10] Yang Y, Liu Y, Huang C F, et al. Aluminium alleviates fluoride toxicity in tea (Camellia sinensis)[J]. Plant Soil, 2016, 402(1): 179−190.
[11] McNeill F E, Mostafaei F, Pidruczny A, et al. Correlation between fluorine content in tea and bone assessed using neutron activation analysis in a Canadian urban population[J]. Journal of Radioanalytical and Nuclear Chemistry, 2016, 309: 389−395. doi: 10.1007/s10967-016-4749-x
[12] Yi X Y, Qiao S, Ma L, et al. Soil fluoride fractions and their bioavailability to tea plants[J]. Environmental Geochemistry and Health, 2017, 39: 1005−1016. doi: 10.1007/s10653-016-9868-3
[13] Wang H Y, Hu T, Wang M H, et al. Biochar addition to tea garden soils: Effects on tea fluoride uptake and accumulation[J]. Biochar, 2023, 5: 37. doi: 10.1007/s42773-023-00220-2
[14] 徐为霞, 林珍珠, 高树芳, 等. 酸性土壤有效氟提取方法研究[J]. 农业环境科学学报, 2006, 25(5): 1388−1392.
Xu W X, Lin Z Z, Gao S F, et al. Extraction method for available fluorine in acid soils[J]. Journal of Agro-Environment Science, 2006, 25(5): 1388−1392.
[15] Deng L, Wang J X, Xu B, et al. Fluorine speciation in loess, related quality assessment, and exposure risks implication in the Shaanxi Loess Plateau[J]. Environmental Earth Sciences, 2022, 81: 326. doi: 10.1007/s12665-022-10437-2
[16] 秦樊鑫, 吴迪, 黄先飞, 等. 高氟病区茶园土壤氟形态及其分布特征[J]. 中国环境科学, 2014, 34(11): 2859−2865.
Qin F X, Wu D, Huang X F, et al. Distribution characteristics and speciation of fluorine in tea garden soils in the high fluoride area[J]. China Environmental Science, 2014, 34(11): 2859−2865.
[17] 侯拓, 冯海艳, 杨忠芳, 等. 山东省桓台地区土壤F的地球化学特征及其影响因素[J]. 地质通报, 2021, 40(9): 1584−1591.
Hou T, Feng H Y, Yang Z F, et al. Geochemical characteristics and influencing factors of soil fluorine in the Huantai area of Shandong Province[J]. Geological Bulletin of China, 2021, 40(9): 1584−1591.
[18] 薛栗尹, 李萍, 王胜利, 等. 干旱区工矿型绿洲城郊农田土壤氟的形态分布特征及其影响因素研究——以白银绿洲为例[J]. 农业环境科学学报, 2012, 31(12): 2407−2414.
Xue L Y, Li P, Wang S L, et al. Chemical forms of fluorine and influential factors in the mining areas of oases, Gansu Province, China[J]. Journal of Agro-Environment Science, 2012, 31(12): 2407−2414.
[19] Loganathan P, Gray C W, Hedley M J, et al. Total and soluble fluorine concentration in relation to properties of soil in New Zealand[J]. European Journal of Soil Science, 2006, 57(3): 411−421. doi: 10.1111/j.1365-2389.2005.00751.x
[20] 李张伟. 粤东凤凰山茶区土壤氟化学形态特征及其影响因素[J]. 环境化学, 2011, 30(8): 1468−1473.
Li Z W. Chemical forms of fluorine in soils from 12 tea gardens of Fenghuang Moutain, east of Guangdong Province[J]. Environmental Chemistry, 2011, 30(8): 1468−1473.
[21] 段文, 石友昌. 土壤和岩石矿物中氟元素分析测试技术研究进展[J]. 岩矿测试, 2023, 42(1): 72−88.
Duan W, Shi Y C. A review of research progress on analysis and testing technology of fluorine in soil and rock minerals.[J]. Rock and Mineral Analysis, 2023, 42(1): 72−88.
[22] 王凌霞, 付庆灵, 胡红青, 等. 湖北茶园茶叶氟含量及土壤分组[J]. 环境化学, 2011, 30(3): 662−667.
Wang L X, Fu Q L, Hu H Q, et al. Fluorine content in tea leaf and fluorine fractionation in soil of tea gardens in Hubei Province[J]. Environmental Chemistry, 2011, 30(3): 662−667.
[23] 徐温新, 李艳, 代允超, 等. 影响小白菜铅吸收的土壤因素和预测模型研究[J]. 农业环境科学学报, 2018, 37(8): 1584−1591.
Xu W X, Li Y, Dai Y C, et al. Determination and prediction of lead uptaked by Brassica chinensis[J]. Journal of Agro-Environment Science, 2018, 37(8): 1584−1591.
[24] 于群英, 李孝良, 汪建飞, 等. 安徽省土壤氟含量及其赋存特征[J]. 长江流域资源与环境, 2013, 22(7): 915−922.
Yu Q Y, Li X L, Wang J F, et al. Content of fluorine and characteristics of fluorine forms in soils of Anhui Province[J]. Resources and Environment in the Yangtze Basin, 2013, 22(7): 915−922.
[25] 李静, 谢正苗, 徐建民, 等. 我国氟的土壤环境质量标准与人体健康关系的研究概况[J]. 土壤通报, 2006, 37(1): 195−199.
Li J, Xie Z M, Xu J M, et al. Research progress in the relationship between soil environmental quality index of fluorine and human health in China[J]. Chinese Journal of Soil Science, 2006, 37(1): 195−199.
[26] 冯雪, 肖斌. 陕西茶园茶叶氟含量及其影响因素[J]. 西北农业学报, 2011, 20(1): 109−113.
Feng X, Xiao B. Fluoride content in tea leaf and its influence factors in Shaanxi Province[J]. Acta Agricultural Boreali-Occidentalis Sinica, 2011, 20(1): 109−113.
[27] Lan D, Wu D S, Li P, et al. Influence of high-fluorine environmental back-ground on crops and human health in hot spring-type fluorosis-diseased areas[J]. Chinese Journal of Geochemistry, 2008, 4: 335−341.
[28] 刘璇, 梁秀娟, 肖霄, 等. pH对吉林西部湖泊底泥中不同形态氟迁移转化的影响的实验研究[J]. 环境污染与防治, 2011, 33(6): 19−22.
Liu X, Liang X J, Xiao X, et al. Experimental study on the impact of pH on the migration and transformation of various forms of fluorine in the lake mud of the Western Jilin[J]. Environmental Pollution & Control, 2011, 33(6): 19−22.
[29] 于群英, 慈恩, 杨林章. 皖北地区土壤中不同形态氟含量及其影响因素[J]. 应用生态学报, 2007, 18(6): 1333−1334.
Yu Q Y, Ci E, Yang L Z, et al. Contents of different soil fluorine forms in North Anhui and their affecting factors[J]. Chinese Journal of Applied Ecology, 2007, 18(6): 1333−1334.
[30] 袁连新, 胡歌鸣. 农业土壤中水溶性氟的分布特征与影响因素分析——以湖北荆州为例[J]. 环境科学与技术, 2011, 34(7): 191−194.
Yuan L X, Hu G M. Spatial distribution characteristics and impact factors of water-soluble fluorine in agricultural soils—A case study of Jingzhou City, Hubei Province[J]. Environmental Science & Technology, 2011, 34(7): 191−194.
[31] 孟昱, 任大军, 张晓晴, 等. 林地土壤氟的形态分布特征及其影响因素[J]. 环境科学与技术, 2019, 42(9): 98−105.
Meng Y, Ren D J, Zhang X Q, et al. Speciation and distribution characteristics of fluorine and its impact factor in forest soil[J]. Environmental Science & Technology, 2019, 42(9): 98−105.
[32] 李永华, 王五一, 杨林生, 等. 陕南土壤中水溶态氟、硒含量及其在生态环境的表征[J]. 环境化学, 2005, 24(3): 279−284.
Li Y H, Wang W Y, Yang L S, et al. Concentration and environmental significance of water soluble-Se and water soluble-F in soils of South Shanxi Province[J]. Environmental Chemistry, 2005, 24(3): 279−284.
[33] 谢忠雷, 邱立民, 董德明, 等. 茶叶中氟含量及其影响因素[J]. 吉林大学自然科学学报, 2001(2): 81−84.
Xie Z L, Qiu L M, Dong D M, et al. Fluoride content of tea leaves and factors affacting the uptake of F from soil into tea leaves[J]. Acta Scientiarium Naturalium Universitatis Jilinensis, 2001(2): 81−84.
[34] 陆丽君, 宗良纲, 罗敏, 等. 江苏典型茶园的茶叶氟含量及其影响因素[J]. 安徽农业科学, 2006, 34(10): 2183−2185.
Lu L J, Zong L G, Luo M, et al. Content of fluoride in tea leaf in Jiangsu Province and its affecting factor[J]. Journal of Anhui Agricultural Sciences, 2006, 34(10): 2183−2185.
[35] 黄春雷, 丛源, 陈岳龙, 等. 晋南临汾—运城盆地土壤氟含量及其影响因素[J]. 地质通报, 2007, 26(7): 878−885.
Huang C L, Cong Y, Chen Y L, et al. Fluorine content in soils of the Linfen—Yuncheng Basin, Southern Shanxi, China, and its influence factors[J]. Geological Bulletin of China, 2007, 26(7): 878−885.
[36] 徐仁扣, 王亚运, 赵安珍, 等. 低分子量有机酸对可变电荷土壤吸附性氟解吸的影响[J]. 土壤, 2003, 35(5): 392−396.
Xu R K, Wang Y Y, Zhao A Z, et al. Effect of low-molecular-weight organic acids on desorption of adsorbed F form variable charge soil[J]. Soils, 2003, 35(5): 392−396.
[37] Pan J T, Li D Q, Zhu J J, et al. Aluminum relieves fluoride stress through stimulation of organic acid production in Camellia sinensis[J]. Physiology and Molecular Biology of Plants, 2020, 26(6): 1127−1137. doi: 10.1007/s12298-020-00813-2
[38] 谢忠雷, 房春生, 孙文田, 等. 柠檬酸-铝-氟交互作用对茶园土壤氟吸附特征及形态分布的影响[J]. 农业环境科学学报, 2007, 26(6): 2271−2286.
Xie Z L, Fang C S, Sun W T, et al. Effects of interaction of citric acid-aluminum-fluoride on the adsorption characteristics and distribution of fluorride in tea garden soil[J]. Journal of Agro-Environment Science, 2007, 26(6): 2271−2286.
[39] 宋文恩, 陈世宝. 基于水稻根伸长的不同土壤中镉(Cd)毒性阈值(EC x)及其预测模型[J]. 中国农业科学, 2014, 47(17): 3434−3443.
Song W E, Chen S B. The toxicity thresholds (EC x) of cadmium (Cd) to rice cultivars as determined by root-elongation tests in soils and its predicted models[J]. Scientia Agricultura Sinica, 2014, 47(17): 3434−3443.
-