-
摘要: 华北地区是我国冬小麦和夏玉米主产区, 过去40多年间, 随着大水漫灌和过量施肥等现象发生, 该地区农田氮淋失呈现加重趋势, 已经对地下水水质产生了严重影响。为探明华北地区面源污染的成因, 进而提出相应阻控措施, 本研究收集了1980—2021年国内外发表的华北地区夏玉米氮淋失研究文献, 选取环境条件和农田管理措施作为自变量, 基于线性模型、指数模型、多项式模型和多元回归模型等对氮淋失量进行模拟预测。结果表明, 氮淋失与水分和肥料氮之间存在较大关联性, 与土壤全氮、有机质含量和黏粒含量呈正相关关系, 与秸秆还田、土层深度、土壤pH、砂粒含量呈现负相关关系。在单变量预测模型中, 氮淋失量与施氮量呈指数关系, 说明在华北地区夏玉米生产中应特别注重优化肥料用量。本研究所获得的多元逐步回归模型(Y总氮淋失量=−23.07+1.14X有机质含量+0.34X黏粒含量−0.13X砂粒含量+0.06X总施氮量+0.18X水分渗漏量, 拟合优度R2=0.414)优于指数模型、线性模型和多项式模型, 具有较好的定量预测效果。考虑到水分渗漏测定过程复杂及方程的可应用性低, 可以采用水分投入量替换水分渗漏量, 但预测精度会受到影响。改善土壤物理条件(如质地)、秸秆还田和优化氮肥和灌溉, 是今后华北地区夏玉米生产中降低氮淋失的关键措施。Abstract: North China has seen intensive flood irrigation and excessive nitrogen (N) fertilization over the past four decades as a main cereal crop-producing region in China. N leaching from farmland in this region has rapidly increased with agricultural intensification, and the non-point source pollution has become increasingly prominent. It is necessary to quantify the amount of N leaching during crop production systematically. Literature on N leaching loss from summer maize production in North China published from 1980–2021 was screened, and soil properties and agricultural management practices were chosen as independent variables to predict N leaching loss based on linear, exponential, polynomial, and multiple regression models. Soil properties included soil organic matter, total N, clay content, sand content, pH, and depth, and agricultural management practices included straw incorporation, N application, and soil water. The results showed that soil water and N fertilizer input significantly influenced N leaching loss. Soil organic matter, soil total N, and clay content positively correlated with the total N leaching amount, whereas straw incorporation, soil depth, pH, and sand content negatively correlated with the total N leaching amount. For the single-factor simulation model, the exponential equation was more appropriate for quantifying total N leaching loss with fertilizer N input than the linear equation, indicating the importance of optimizing fertilizer N in summer maize production in North China. It also indicated that the risk of excess N leaching from summer maize production in North China was relatively high after a certain threshold of fertilizer N input, and optimization of N fertilization should be adopted as an important practice. Unlike many previous studies that directly selected fertilizer N input for predicting N leaching loss, this study combined N (total N rate, N surplus) and water (water input, water balance, water percolation) in various combinations to obtain an optimal prediction combination. The combination of the total N rate and water percolation had the highest R2 (0.3413). The stepwise regression equation of Ytotal N leaching loss=−23.07+1.14Xsoil organic matter+0.34Xclay content−0.13Xsand content+0.06Xtotal N rate+0.18Xwater percolation (R2=0.414) was better than the prediction effects of exponential, linear, and polynomial models. The standardized regression coefficients of the predictive variables were 0.18, 0.11, 0.07, 0.23, and 0.31 for soil organic matter, clay content, sand content, total N rate, and water percolation, respectively, which showed that water percolation was the most important, followed by total N rate and soil organic matter. Considering the complexity of the water percolation calculation process, the water input can be used to replace water percolation in the equation, that is, Ytotal N leaching loss=−18.60+0.64Xsoil organic matter−10.27Xstraw incorporation−0.30Xsand content+0.13Xtotal N rate+0.04Xwater input; however, the prediction accuracy of the regression equation was affected. Future research on predicting N leaching loss in North China should focus on accurately quantifying water percolation. The quantitative model obtained in this study provides technical support for precise N management and effective pollution prevention in North China.
-
表 1 夏玉米农田总氮淋失量与氮水两预测变量间的多元回归模拟
Table 1 Multiple regression simulation between total N leaching loss and pairwise indexes of N and water in summer maize fields
预测变量组合 Predictive variables combination 决定系数 R2 回归方程 Regression equation 总施氮量+水分投入量 Total N rate+Water input 0.2435 YNL=−20.55+0.13XNR+0.04XWI 总施氮量+水平衡 Total N rate+Water balance 0.2206 YNL=−3.33+0.13XNR+0.02XWB 总施氮量+水分渗漏量 Total N rate+Water percolation 0.3413 YNL=−5.46+0.06XNR+0.19XWP 氮盈余+水分投入量 N surplus+Water input 0.2450 YNL=−2.14+0.13XNS+0.04XWI 氮盈余+水平衡 N surplus+Water balance 0.2188 YNL= 16.00+0.13XNS+0.02XWB 氮盈余+水分渗漏量 N surplus+Water percolation 0.3001 YNL= 3.98+0.05XNS+0.19XWP 回归方程中, 总施氮量、氮盈余分别用NR、NS表示; 水分投入量、水平衡、水分渗漏量分别用WI、WB、WP表示; 总氮淋失量用NL表示。NR: total N rate; NS: N surplus; WI: water input; WB: water balance; WP: water percolation; NL: total N leaching loss. 表 2 夏玉米农田总氮淋失量的多元回归模型参数
Table 2 Parameters of multiple regression model for total N leaching loss in summer maize fields
系数预测值
Estimate
coefficient标准差
Std. errort值
t valueP值
P value截距 Intercept −18.13 20.36 −0.89 0.375 有机质含量
Soil organic matter0.67 0.49 1.37 0.172 土壤全氮
Soil total N13.83 10.17 1.36 0.176 黏粒含量
Clay content0.40 0.19 2.11 0.037 砂粒含量
Sand content−0.14 0.07 −2.02 0.045 土壤pH
Soil pH−0.61 2.38 −0.26 0.798 土层深度
Soil depth−0.03 0.03 −1.11 0.268 秸秆还田
Straw incorporation−4.45 3.11 −1.43 0.155 总施氮量
Total N rate0.06 0.01 4.78 3.72×10−6 水分渗漏量
Water percolation0.16 0.02 7.03 4.38×10−11 F值 F statistic: 15.74 P值 P value: 2.2×10−16 拟合优度 Multiple R2: 0.4432 修正拟合优度 Adjusted R2: 0.4150 表 3 夏玉米农田总氮淋失量的逐步回归模型参数
Table 3 Parameters of stepwise regression model for total N leaching loss in summer maize fields
系数预测值
Estimated
coefficient标准差
Std. errort值
t valueP值
P value截距 Intercept −23.07 6.28 −3.68 3.12×10−4 有机质含量
Soil organic matter1.14 0.23 4.96 1.61×10−6 黏粒含量
Clay content0.34 0.15 2.20 0.029 砂粒含量
Sand content−0.13 0.07 −2.02 0.045 总施氮量
Total N rate0.06 0.01 5.13 7.35×10−7 水分渗漏量
Water percolation0.18 0.02 8.42 1.11×10−14 F值 F statistic: 27.36 P值 P value: 2.2×10−16 拟合优度 Multiple R2: 0.4291 修正拟合优度 Adjusted R2: 0.4140 -
[1] TILMAN D, BALZER C, HILL J, et al. Global food demand and the sustainable intensification of agriculture[J]. Proceedings of the National Academy of Sciences of the United States of America, 2011, 108(50): 20260−20264 doi: 10.1073/pnas.1116437108
[2] 中华人民共和国国家统计局. 中国统计年鉴2021[EB/OL]. [2022-11-04]. http://www.stats.gov.cn/sj/ndsj/2021/indexch.htm National Bureau of Statistics of China. China Statistical Yearbook, 2021[EB/OL]. [2022-11-04]. http://www.stats.gov.cn/sj/ndsj/2021/indexch.htm
[3] 孟凡乔, 王坤, 肖广敏, 等. 华北平原潮土区粮田氮淋失阻控措施及效果分析[J]. 中国生态农业学报(中英文), 2021, 29(1): 141−153 MENG F Q, WANG K, XIAO G M, et al. Nitrogen leaching mitigation in fluvo-aquic soil in the North China Plain[J]. Chinese Journal of Eco-Agriculture, 2021, 29(1): 141−153
[4] 闫湘, 金继运, 梁鸣早. 我国主要粮食作物化肥增产效应与肥料利用效率[J]. 土壤, 2017, 49(6): 1067−1077 YAN X, JIN J Y, LIANG M Z. Fertilizer use efficiencies and yield-increasing rates of grain crops in China[J]. Soils, 2017, 49(6): 1067−1077
[5] 宋涛, 尹俊慧, 胡兆平, 等. 脲酶/硝化抑制剂减少农田土壤氮素损失的作用特征[J]. 农业资源与环境学报, 2021, 38(4): 585−597 SONG T, YIN J H, HU Z P, et al. Characteristics of urease/nitrification inhibitors in reducing nitrogen losses in farmland soils[J]. Journal of Agricultural Resources and Environment, 2021, 38(4): 585−597
[6] YING H, XUE Y F, YAN K, et al. Safeguarding food supply and groundwater safety for maize production in China[J]. Environmental Science & Technology, 2020, 54(16): 9939−9948
[7] 李晓欣, 张菲菲, 马洪斌, 等. 华北平原地区农田硝态盐淋失研究进展[J]. 华北农学报, 2011, 26(S2): 131−139 doi: 10.7668/hbnxb.2011.S2.030 LI X X, ZHANG F F, MA H B, et al. Nitrate leaching in North China Plain: a review[J]. Acta Agriculturae Boreali-Sinica, 2011, 26(S2): 131−139 doi: 10.7668/hbnxb.2011.S2.030
[8] 殷乐宜, 李璐, 陈坚, 等. 京津冀重点区域地下水硝酸盐污染分区研究[J]. 环境保护科学, 2021, 47(5): 118−122 YIN L Y, LI L, CHEN J, et al. Study on nitrate pollution zoning in groundwater of key area of Beijing-Tianjin-Hebei Region[J]. Environmental Protection Science, 2021, 47(5): 118−122
[9] 许莹, 孙良杰, 杜立宇, 等. 常规田间管理条件下旱田土壤氮素淋失影响因素研究进展[J]. 土壤通报, 2020, 51(5): 1246−1254 XU Y, SUN L J, DU L Y, et al. Influencing factors on soil nitrogen leaching under traditional management of dry farmland[J]. Chinese Journal of Soil Science, 2020, 51(5): 1246−1254
[10] ZHOU M H, BUTTERBACH-BAHL K. Assessment of nitrate leaching loss on a yield-scaled basis from maize and wheat cropping systems[J]. Plant and Soil, 2014, 374(1): 977−991
[11] WANG G L, CHEN X P, CUI Z L, et al. Estimated reactive nitrogen losses for intensive maize production in China[J]. Agriculture, Ecosystems & Environment, 2014, 197: 293−300
[12] CUI Z L, ZHANG H Y, CHEN X P, et al. Pursuing sustainable productivity with millions of smallholder farmers[J]. Nature, 2018, 555(7696): 363−366 doi: 10.1038/nature25785
[13] 胡玉婷, 廖千家骅, 王书伟, 等. 中国农田氮淋失相关因素分析及总氮淋失量估算[J]. 土壤, 2011, 43(1): 19–25 HU Y T, LIAO Q J H, WANG S W, et al. Statistical analysis and estimation of N leaching from agricultural fields in China[J]. Soils, 2011, 43(1): 19–25
[14] 李利霞, 武桂芝, 于宗民, 等. 大沽河流域农田土壤磷有效性及全磷淋失影响因素试验[J]. 水土保持学报, 2022, 36(2): 337−343 LI L X, WU G Z, YU Z M, et al. Experimental study on influencing factors affecting phosphorus availability and total phosphorus leaching in farmland soil in Dagu River Basin[J]. Journal of Soil and Water Conservation, 2022, 36(2): 337−343
[15] 叶英聪, 张丽君, 谢文, 等. 南方丘陵稻田土壤全钾和速效钾高光谱特征与反演模型研究[J]. 广东农业科学, 2015, 42(7): 37−42 YE Y C, ZHANG L J, XIE W, et al. Prediction on total potassium and available potassium content of hilly paddy soil in southern China based on hyper-spectral characteristics[J]. Guangdong Agricultural Sciences, 2015, 42(7): 37−42
[16] 刘健. 三种质地土壤氮素淋溶规律研究[D]. 北京: 北京林业大学, 2010 LIU J. Study on nitrogen leaching regulations on three textures of soil[D]. Beijing: Beijing Forestry University, 2010
[17] CANNAVO P, HARMAND J M, ZELLER B, et al. Low nitrogen use efficiency and high nitrate leaching in a highly fertilized Coffea arabica-Inga densiflora agroforestry system: a 15N labeled fertilizer study[J]. Nutrient Cycling in Agroecosystems, 2013, 95(3): 377−394 doi: 10.1007/s10705-013-9571-z
[18] 汪兆辉, 张友良, 冯绍元. 旱地硝态氮淋失阻控措施研究进展[J]. 中国农村水利水电, 2021(12): 39−45 doi: 10.3969/j.issn.1007-2284.2021.12.007 WANG Z H, ZHANG Y L, FENG S Y. Review of soil nitrate leaching control measures in dry farmland[J]. China Rural Water and Hydropower, 2021(12): 39−45 doi: 10.3969/j.issn.1007-2284.2021.12.007
[19] CECCON P, DALLA COSTA L, DELLE VEDOVE G, et al. Nitrogen in drainage water as influenced by soil depth and nitrogen fertilization: a study in lysimeters[J]. European Journal of Agronomy, 1995, 4(3): 289−298 doi: 10.1016/S1161-0301(14)80029-4
[20] DELIN S, STENBERG M. Effect of nitrogen fertilization on nitrate leaching in relation to grain yield response on loamy sand in Sweden[J]. European Journal of Agronomy, 2014, 52: 291−296 doi: 10.1016/j.eja.2013.08.007
[21] 王桂良. 中国三大粮食作物农田活性氮损失与氮肥利用率的定量分析[D]. 北京: 中国农业大学, 2014 WANG G L. Quantitative analysis of reactive nitrogen losses and nitrogen use efficiency of three major grain in China[D]. Beijing: China Agricultural University, 2014
[22] 王兴武, 于强, 张国梁, 等. 鲁西北平原夏玉米产量与土壤硝态氮淋失[J]. 地理研究, 2005, 24(1): 140−150 WANG X W, YU Q, ZHANG G L, et al. The yield and dynamics of soil nitrate for summer maize on the plain of northwest Shandong Province[J]. Geographical Research, 2005, 24(1): 140−150
[23] 康爱林, 孟凡乔, 李虎, 等. 滴灌施肥对华北地区冬小麦-夏玉米作物产量及水氮利用效率的影响[J]. 土壤通报, 2020, 51(4): 958−968 KANG A L, MENG F Q, LI H, et al. Effects of drip irrigation fertilization on wheat and maize yields and water- and nitrogen-use efficiency in northern China[J]. Chinese Journal of Soil Science, 2020, 51(4): 958−968
[24] 胡春胜, 张玉铭, 秦树平, 等. 华北平原农田生态系统氮素过程及其环境效应研究[J]. 中国生态农业学报, 2018, 26(10): 1501−1514 HU C S, ZHANG Y M, QIN S P, et al. Nitrogen processes and related environmental effects on agro-ecosystem in the North China Plain[J]. Chinese Journal of Eco-Agriculture, 2018, 26(10): 1501−1514
[25] 杨旺鑫. 我国农田氮磷损失影响因素及损失量初步估算[D]. 南京: 南京农业大学, 2015 YANG W X. Influencing factors and estimation of nitrogen and phosphorus losses from farmlands in China[D]. Nanjing: Nanjing Agricultural University, 2015
[26] 朱波, 周明华, 况福虹, 等. 紫色土坡耕地氮素淋失通量的实测与模拟[J]. 中国生态农业学报, 2013, 21(1): 102−109 ZHU B, ZHOU M H, KUANG F H, et al. Measurement and simulation of nitrogen leaching loss in hillslope cropland of purple soil[J]. Chinese Journal of Eco-Agriculture, 2013, 21(1): 102−109
[27] 赖晓明, 廖凯华, 朱青, 等. 基于Hydrus-1D模型的太湖流域农田系统水分渗漏和氮磷淋失特征分析[J]. 长江流域资源与环境, 2015, 24(9): 1491−1498 doi: 10.11870/cjlyzyyhj201509008 LAI X M, LIAO K H, ZHU Q, et al. Feature analysis of soil water leakage and leaching of nitrogen and phosphorus in the typical farmland of Taihu Lake basin based on Hydrus-1D model[J]. Resources and Environment in the Yangtze Basin, 2015, 24(9): 1491−1498 doi: 10.11870/cjlyzyyhj201509008
[28] 李晓鹏, 张佳宝, 刘金涛, 等. 天然文岩渠流域土壤水分渗漏和氮素淋失模拟[J]. 环境科学, 2009, 30(3): 864−869 LI X P, ZHANG J B, LIU J T, et al. Simulating soil water drainage and nitrogen leaching in Tianranwenyanqu basin[J]. Environmental Science, 2009, 30(3): 864−869
[29] 杜艾芳. 运用WHCNS模型对农田氮素损失的验证及分析[J]. 价值工程, 2022, 41(14): 142−144 DU A F. Verification and analysis of nitrogen loss in farmland using WHCNS model[J]. Value Engineering, 2022, 41(14): 142−144
[30] 俞映倞, 薛利红, 杨林章. 不同氮肥管理模式对太湖流域稻田土壤氮素渗漏的影响[J]. 土壤学报, 2011, 48(5): 988−995 YU Y L, XUE L H, YANG L Z. Effects of nitrogen management on nitrogen leaching of paddy soil in Taihu Lake Region[J]. Acta Pedologica Sinica, 2011, 48(5): 988−995
[31] 黄明蔚, 刘敏, 陆敏, 等. 稻麦轮作农田系统中氮素渗漏流失的研究[J]. 环境科学学报, 2007, 27(4): 629−636 doi: 10.3321/j.issn:0253-2468.2007.04.015 HUANG M W, LIU M, LU M, et al. Study on the nitrogen leaching in the paddy-wheat rotation agroecosystem[J]. Acta Scientiae Circumstantiae, 2007, 27(4): 629−636 doi: 10.3321/j.issn:0253-2468.2007.04.015
[32] 张玉珍. 农田不同土地利用氮素渗漏量的研究[J]. 福州大学学报(自然科学版), 2006, 34(4): 620−624 ZHANG Y Z. Assessment of nitrogen leaching amount on various land use in field[J]. Journal of Fuzhou University (Natural Science Edition), 2006, 34(4): 620−624
[33] QIN S P, WANG Y Y, HU C S, et al. Yield-scaled N2O emissions in a winter wheat summer corn double-cropping system[J]. Atmospheric Environment, 2012, 55: 240−244 doi: 10.1016/j.atmosenv.2012.02.077
[34] 丁燕, 杨宪龙, 同延安, 等. 小麦-玉米轮作体系农田氮素淋失特征及氮素表观平衡[J]. 环境科学学报, 2015, 35(6): 1914−1921 DING Y, YANG X L, TONG Y A, et al. Characteristics of N leaching and apparent N budget in cultivated lands under a winter wheat-summer maize rotation system[J]. Acta Scientiae Circumstantiae, 2015, 35(6): 1914−1921
[35] 林立, 胡克林, 李光德, 等. 高产粮区不同施肥模式下玉米季农田氮素损失途径分析[J]. 环境科学, 2011, 32(9): 2617−2624 doi: 10.13227/j.hjkx.2011.09.013 LIN L, HU K L, LI G D, et al. Evaluation of nitrogen loss way in summer maize system under different fertilizer N managements[J]. Environmental Science, 2011, 32(9): 2617−2624 doi: 10.13227/j.hjkx.2011.09.013
[36] 王西娜, 王朝辉, 李生秀. 黄土高原旱地冬小麦/夏玉米轮作体系土壤的氮素平衡[J]. 植物营养与肥料学报, 2006, 12(6): 759−764 doi: 10.3321/j.issn:1008-505X.2006.06.001 WANG X N, WANG Z H, LI S X. Soil nitrogen balance in winter wheat and summer maize rotation system on dryland of Loess Plateau[J]. Plant Nutrition and Fertilizer Science, 2006, 12(6): 759−764 doi: 10.3321/j.issn:1008-505X.2006.06.001
[37] 刘学军, 巨晓棠, 张福锁. 减量施氮对冬小麦-夏玉米种植体系中氮利用与平衡的影响[J]. 应用生态学报, 2004, 15(3): 458−462 doi: 10.3321/j.issn:1001-9332.2004.03.020 LIU X J, JU X T, ZHANG F S. Effect of reduced N application on N utilization and balance in winter wheat-summer maize cropping system[J]. Chinese Journal of Applied Ecology, 2004, 15(3): 458−462 doi: 10.3321/j.issn:1001-9332.2004.03.020
[38] 黄学茹. 铁氧化物与有机质对酸性土壤硝化作用的影响[D]. 重庆: 西南大学, 2016 HUANG X R. Effects of iron oxide and organic matter on acidic soil nitrification[D]. Chongqing: Southwest University, 2016
[39] 王永生. 宁夏黄灌区农田有机质对土壤硝态氮淋失量的影响研究[D]. 北京: 中国农业科学院, 2011 WANG Y S. Study on soil organic matter effect on soil nitrate nitrogen leaching losses in Ningxia Yellow River Irrigation Area[D]. Beijing: Chinese Academy of Agricultural Sciences, 2011
[40] ZHOU J B, XI J G, CHEN Z J, et al. Leaching and transformation of nitrogen fertilizers in soil after application of N with irrigation: a soil column method[J]. Pedosphere, 2006, 16(2): 245−252 doi: 10.1016/S1002-0160(06)60050-7
[41] WANG M, PENDALL E, FANG C M, et al. A global perspective on agroecosystem nitrogen cycles after returning crop residue[J]. Agriculture, Ecosystems & Environment, 2018, 266: 49−54
[42] CHENG Y, WANG J, WANG J Y, et al. The quality and quantity of exogenous organic carbon input control microbial NO3− immobilization: a meta-analysis[J]. Soil Biology and Biochemistry, 2017, 115: 357−363 doi: 10.1016/j.soilbio.2017.09.006
[43] 张鑫, 李菁园, 孟凡乔, 等. 桓台县冬小麦和夏玉米秸秆长期还田的生态效益分析[J]. 生态学报, 2020, 40(12): 4157−4168 ZHANG X, LI J Y, MENG F Q, et al. Ecological impacts of winter wheat and summer maize straw incorporation in Huantai County, Shandong Province[J]. Acta Ecologica Sinica, 2020, 40(12): 4157−4168
[44] 方匡南, 吴见彬, 朱建平, 等. 随机森林方法研究综述[J]. 统计与信息论坛, 2011, 26(3): 32−38 doi: 10.3969/j.issn.1007-3116.2011.03.006 FANG K N, WU J B, ZHU J P, et al. A review of technologies on random forests[J]. Statistics & Information Forum, 2011, 26(3): 32−38 doi: 10.3969/j.issn.1007-3116.2011.03.006