Influence of lateral recharge in mountainous areas on groundwater recharge and nitrate dynamics in the Hutuo River alluvial-pluvial fan
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摘要: 山区侧向补给是华北山前平原冲洪积扇含水层重要补给来源, 影响平原区地下水水量和水质动态。近年来受极端气候和人类活动影响, 山区对冲洪积扇平原区地下水的侧向补给机制及其对地下水硝酸盐动态的影响仍不明确。本研究以滹沱河冲洪积扇为研究区, 利用水文观测、水化学和同位素示踪等方法, 估算山区侧向补给通量和硝酸盐输移通量, 揭示山区侧向补给与平原区地下水的补给关系, 分析山区侧向补给对地下水硝酸盐分布的影响。根据水文地质条件, 将采样点划分为4个子区: 滹沱河冲洪积扇北部扇顶(Ⅰ区)、扇中(Ⅱ区)、滹沱河附近扇缘区(Ⅲ区)以及滹沱河冲洪积扇南部区域(Ⅳ区)。地下水硝酸盐动态监测数据表明, 滹沱河北部的山区断面地下水硝酸盐浓度高于南部断面, 平原区北部Ⅰ区和Ⅱ区地下水硝酸盐浓度高于南部Ⅳ区; 且沿地下水流动方向, 地下水硝酸盐浓度均值呈现Ⅰ区(105.28 mg·L−1)>Ⅱ区(99.22 mg·L−1)>Ⅳ区(37.10 mg·L−1)>Ⅲ区(23.08 mg·L−1)的空间分布特征。利用地下水氢氧同位素示踪揭示了山区侧向流对冲洪积扇北部地下水补给影响范围为扇顶和扇中, 而冲洪积扇南部因地下水超采改变地下水流场, 其影响范围主要为扇顶。利用达西定律计算2022年3月至2023年2月山区侧向流对滹沱河冲洪积扇平原区的补给量为2.10×108 m3, 硝酸盐通量为239.56×105 kg, 且北部山区侧向补给的水氮通量大于南部, 这也是影响平原区地下水硝酸盐空间分布的重要原因。山区侧向补给对冲洪积扇平原区地下水量和水质的影响不容忽视, 因此, 实现源头综合治理, 降低山区地下水污染物浓度, 对下游平原区面源污染管理, 防止地下水硝酸盐污染具有重要意义。Abstract: Lateral recharge in mountainous areas is an important recharge source for the alluvial-pluvial fans in the Piedmont Plain of North China, which affects the dynamics of the quantity and quality of groundwater in plain areas. In recent years, the mechanism of lateral recharge in mountainous areas of groundwater in alluvial-pluvial fans and its influence on the dynamics of nitrate in groundwater in plain areas have remained unknown due to extreme climate and human activities. Through hydrological observation and hydrochemical and isotope tracer methods across the Hutuo River alluvial-pluvial fan, we estimated the lateral recharge flux and nitrate transport flux in mountainous areas, revealed the recharge relationship between lateral recharge in mountainous areas and groundwater in plain areas, and analyzed the influence of lateral recharge in mountainous areas on the distribution of groundwater nitrate in plain areas. The sampling sites were divided into four sub-regions according to their hydrogeological conditions: the northern top part (Zone Ⅰ) and the middle (Zone Ⅱ) of the Hutuo River alluvial-pluvial fan, the fan margin area near the Hutuo River (Zone Ⅲ), and the southern part of the Hutuo River alluvial-pluvial fan (Zone Ⅳ). The monitoring data of groundwater nitrate dynamics showed that the nitrate concentration of groundwater in the mountainous section of the northern Hutuo River was higher than that in the southern section, and the nitrate concentration of groundwater in Zones Ⅰ and Ⅱ of the northern alluvial-pluvial fan plain was higher than that in Zone Ⅳ. Along the direction of groundwater flow, the mean concentration of groundwater nitrate showed a spatial distribution pattern of Zone Ⅰ (105.28 mg·L−1) > Zone Ⅱ (99.22 mg·L−1) > Zone Ⅳ (37.10 mg·L−1) > Zone Ⅲ (23.08 mg·L−1). The results revealed that the influenced areas by lateral recharge in mountainous areas in the northern part of the alluvial fan were the top and middle of the fan. However, the influenced area in the southern part of the alluvial fan was mainly the top of the fan because the groundwater flow field was changed by overexploitation. Darcy’s law was used to calculate the amount of lateral recharge in the mountainous areas of the Hutuo River alluvial-pluvial fan from March 2022 to February 2023. The results showed that amount of lateral recharge was 2.10×108 m3, and the nitrate flux was 239.56×105 kg. Moreover, the water and nitrate fluxes of lateral recharge in the northern mountainous areas were greater than those in the south, which was also an important factor affecting the spatial distribution of groundwater nitrate in the plain area. The impact of lateral recharge in mountainous areas on the quantity and quality of groundwater in the alluvial-pluvial fan cannot be ignored. Therefore, it is of great significance to achieve comprehensive treatment of groundwater sources and reduce the concentration of groundwater pollutants in mountainous areas for non-point source pollution management and groundwater nitrate pollution prevention in the downstream plain area.
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图 1 研究区地形地貌及采样点分布
Ⅰ、Ⅱ、Ⅲ、Ⅳ分别表示滹沱河冲洪积扇北部扇顶、扇中、滹沱河附近扇缘区以及滹沱河冲洪积扇南部区域。Ⅰ, Ⅱ, Ⅲ and Ⅳ represent the northern top, middle parts of the Hutuo River alluvial-pluvial fan, the fan margin area near the Hutuo River, and the southern part of the Hutuo River alluvial-pluvial fan, respectively.
Figure 1. Geographic location and topography and distribution of sampling sites of the study area
图 3 滹沱河冲洪积扇区断面监测孔地下水水位变化(左侧)及地下水硝酸盐浓度变化(右侧)
S1-S5分别代表断面1-5, JC1-JC10代表监测孔1-10。S1-S5 represent section 1-5, respectively; and JC1-JC10 represent monitoring hole 1-10, respectively.
Figure 3. Change of groundwater level (left) and nitrate concentration (right) in the monitoring holes at the sections of the Hutuo River alluvial-pluvial fan
图 5 2020年滹沱河冲洪积扇平原区各分区地下水硝酸盐浓度空间分布
Ⅰ、Ⅱ、Ⅲ、Ⅳ分别表示滹沱河冲洪积扇北部扇顶、扇中、滹沱河附近扇缘区以及滹沱河冲洪积扇南部区域。Ⅰ, Ⅱ, Ⅲ and Ⅳ represent the northern top, middle parts of the alluvial-pluvial fan of the Hutuo River, the fan margin area near the Hutuo River, and the southern part of the alluvial-pluvial fan of the Hutuo River, respectively.
Figure 5. Spatial distribution of nitrate concentration in groundwater in the plain area of each subregion in the Hutuo River alluvial-pluvial fan in 2020
图 8 滹沱河冲洪积扇区断面监测孔地下水、各分区[北部Ⅰ~Ⅲ区(a), 南部Ⅳ区(b)]地下水及土壤水δ2H、δ18O关系图
采用栾城试验站降水同位素数据拟合当地大气降水线(LMWL: δ2H = 6.38 δ18O−3.84), 土壤水同位素为均值。VSMOW表示维也纳平均海洋水标准, GMWL表示全球大气降水线。The local meteoric water line (LMWL: δ2H = 6.38 δ18O−3.84) was fitted by the precipitation isotope data of Luancheng Station, and the soil water isotope was the mean value. VSMOW refers to Vienna Standard Mean Ocean Water, and GMWL refers to the global meteoric water line.
Figure 8. Relationships of δ2H and δ18O for groundwater in monitoring holes at sections, and groundwater and soil water in each subregion [northern I-Ⅲ (a), southern Ⅳ (b)] of the Hutuo River alluvial-pluvial fan
表 1 2022年3月—2023年2月滹沱河冲洪积扇区山区侧向补给对平原区地下水的补给量
Table 1. Lateral recharge in the mountainous areas of the Hutuo River alluvial-pluvial fan from March 2022 to February 2023
×108 m3 断面
Section侧向补给量 Amount of lateral recharge 2022 2023 总计
Total3月
March4月
April5月
May6月
June7月
July8月
August9月
September10月
October11月
November12月
December1月
January2月
February1 0.096 0.095 0.100 0.099 0.104 0.101 0.096 0.099 0.095 0.098 0.097 0.087 1.167 2 0.024 0.023 0.024 0.024 0.024 0.024 0.024 0.025 0.024 0.025 0.026 0.023 0.290 3 0.028 0.030 0.031 0.029 0.031 0.029 0.027 0.028 0.028 0.029 0.029 0.026 0.346 4 0.023 0.022 0.023 0.023 0.022 0.023 0.022 0.023 0.023 0.020 0.023 0.022 0.271 5 0.003 0.002 0.003 0.003 0.002 0.002 0.002 0.002 0.002 0.002 0.003 0.003 0.029 总计 Total 0.174 0.172 0.181 0.178 0.183 0.179 0.171 0.177 0.172 0.174 0.178 0.161 2.103 表 2 2022年3月—2023年2月滹沱河冲洪积扇区山区输入硝酸盐通量
Table 2. Nitrate fluxes from lateral recharge in mountainous areas of the Hutuo River alluvial-pluvial fan from March 2022 to February 2023
×105 kg 断面
Section硝酸盐通量 Nitrate flux 2022 2023 总计
Total3月
March4月
April5月
May6月
June7月
July8月
August9月
September10月
October11月
November12月
December1月
January2月
February1 4.99 4.47 4.79 5.03 4.01 4.53 4.38 4.67 3.77 3.34 3.44 2.72 50.13 2 11.03 11.55 12.32 10.37 4.65 10.39 11.53 11.38 10.57 10.42 10.61 9.40 124.23 3 4.74 4.69 4.33 3.64 3.21 2.93 3.70 4.62 4.32 4.31 4.38 4.12 48.98 4 1.55 1.65 1.47 1.08 0.81 1.17 1.08 1.37 1.08 0.86 0.89 0.88 13.88 5 0.18 0.23 0.25 0.23 0.16 0.21 0.20 0.21 0.17 0.17 0.16 0.15 2.33 总计 Total 22.48 22.59 23.16 20.35 12.84 19.23 20.89 22.24 19.90 19.10 19.49 17.27 239.56 -
[1] LI F D, PAN G Y, TANG C Y, et al. Recharge source and hydrogeochemical evolution of shallow groundwater in a complex alluvial fan system, southwest of North China Plain[J]. Environmental Geology, 2008, 55(5): 1109−1122 doi: 10.1007/s00254-007-1059-1 [2] WADA Y. Modeling groundwater depletion at regional and global scales: present state and future prospects[J]. Surveys in Geophysics, 2016, 37(2): 419−451 doi: 10.1007/s10712-015-9347-x [3] DASKALAKI P, VOUDOURIS K. Groundwater quality of porous aquifers in Greece: a synoptic review[J]. Environmental Geology, 2008, 54(3): 505−513 doi: 10.1007/s00254-007-0843-2 [4] ZHANG Q Q, WANG H W, WANG L. Tracing nitrate pollution sources and transformations in the over-exploited groundwater region of North China using stable isotopes[J]. Journal of Contaminant Hydrology, 2018, 218: 1−9 doi: 10.1016/j.jconhyd.2018.06.001 [5] SMITH M, CROSS K, PADEN M, et al. Spring-Managing Groundwater Sustainably[M]. Gland, Switzerland: IUCN, 2016: 33−38 [6] GUO X Y, FENG Q, SI J H, et al. Identifying the origin of groundwater for water resources sustainable management in an arid oasis, China[J]. Hydrological Sciences Journal, 2019, 64(10): 1253−1264 doi: 10.1080/02626667.2019.1619080 [7] WILSON J L, GUAN H D. Mountain-block hydrology and mountain-front recharge[M]//BLASCH K, FERRE P A, HOFFMANN J, et al. Groundwater Recharge in a Desert Environment: The Southwestern United States. Washington, D. C.: American Geophysical Union, 2004: 113–137 [8] 张兆吉, 费宇红, 郭春艳, 等. 华北平原区域地下水污染评价[J]. 吉林大学学报(地球科学版), 2012, 42(5): 1456−1461 doi: 10.13278/j.cnki.jjuese.2012.05.014ZHANG Z J, FEI Y H, GUO C Y, et al. Regional groundwater contamination assessment in the North China Plain[J]. Journal of Jilin University (Earth Science Edition), 2012, 42(5): 1456−1461 doi: 10.13278/j.cnki.jjuese.2012.05.014 [9] ZHANG Q Q, WANG H W. Assessment of sources and transformation of nitrate in the alluvial-pluvial fan region of North China using a multi-isotope approach[J]. Journal of Environmental Sciences, 2020, 89: 9−22 doi: 10.1016/j.jes.2019.09.021 [10] 王仕琴, 檀康达, 郑文波, 等. 白洋淀流域浅层地下水硝酸盐分布及来源的区域分异特征[J]. 中国生态农业学报(中英文), 2021, 29(1): 230−240WANG S Q, TAN K D, ZHENG W B, et al. Regional characteristics of nitrate sources and distributions in the shallow groundwater of the Lake Baiyangdian watershed[J]. Chinese Journal of Eco-Agriculture, 2021, 29(1): 230−240 [11] 刘中培. 农业活动对区域地下水变化影响研究——以石家庄平原区为例[D]. 北京: 中国地质科学院, 2010LIU Z P. Study on the influence of agricultural activities on regional groundwater change−a case study of Shijiazhuang Plain[D]. Beijing: Chinese Academy of Geological Sciences, 2010 [12] 王金哲, 张光辉, 严明疆, 等. 水坝建设对滹沱河流域平原区地下水系统干扰结果分析[J]. 南水北调与水利科技, 2009, 7(4): 78−81 doi: 10.3969/j.issn.1672-1683.2009.04.022WANG J Z, ZHANG G H, YAN M J, et al. Analysis of shallow groundwater in the Hutuohe River Basin after the dam construction[J]. South-to-North Water Transfers and Water Science & Technology, 2009, 7(4): 78−81 doi: 10.3969/j.issn.1672-1683.2009.04.022 [13] COUMOU D, RAHMSTORF S. A decade of weather extremes[J]. Nature Climate Change, 2012, 2(7): 491−496 doi: 10.1038/nclimate1452 [14] LONG D, YANG W T, SCANLON B R, et al. South-to-North Water Diversion stabilizing Beijing’s groundwater levels[J]. Nature Communications, 2020, 11: 3665 doi: 10.1038/s41467-020-17428-6 [15] ZHANG C, DUAN Q Y, YEH P J F, et al. Sub-regional groundwater storage recovery in North China Plain after the South-to-North water diversion project[J]. Journal of Hydrology, 2021, 597: 126156 doi: 10.1016/j.jhydrol.2021.126156 [16] 赵焕, 王仕琴, 孔晓乐, 等. 华北低山丘陵区潴龙河流域地下水水质特征及成因分析[J]. 水文地质工程地质, 2016, 43(2): 17−24 doi: 10.16030/j.cnki.issn.1000-3665.2016.02.03ZHAO H, WANG S Q, KONG X L, et al. A study of the water quality characteristics and factors in the Zhulong River Basin in the hilly region of North China[J]. Hydrogeology and Engineering Geology, 2016, 43(2): 17−24 doi: 10.16030/j.cnki.issn.1000-3665.2016.02.03 [17] 王仕琴, 郑文波, 孔晓乐. 华北农区浅层地下水硝酸盐分布特征及其空间差异性[J]. 中国生态农业学报, 2018, 26(10): 1476−1482 doi: 10.13930/j.cnki.cjea.180639WANG S Q, ZHENG W B, KONG X L. Spatial distribution characteristics of nitrate in shallow groundwater of the agricultural area of the North China Plain[J]. Chinese Journal of Eco-Agriculture, 2018, 26(10): 1476−1482 doi: 10.13930/j.cnki.cjea.180639 [18] WANG S Q, TANG C Y, SONG X F, et al. Factors contributing to nitrate contamination in a groundwater recharge area of the North China Plain[J]. Hydrological Processes, 2016, 30(13): 2271−2285 doi: 10.1002/hyp.10778 [19] WANG S Q, TANG C Y, SONG X F, et al. Using major ions and δ15N-NO3− to identify nitrate sources and fate in an alluvial aquifer of the Baiyangdian Lake watershed, North China Plain[J]. Environmental Science: Processes & Impacts, 2013, 15(7): 1430−1443 [20] TANG C, CHEN J Y, SHEN Y J. Long-term effect of wastewater irrigation on nitrate in groundwater in the North China Plain[J]. Tunnelling and Underground Space Technology, 2004, 17: 48−49 [21] HUANG T M, PANG Z H, YUAN L J. Nitrate in groundwater and the unsaturated zone in (semi) arid Northern China: baseline and factors controlling its transport and fate[J]. Environmental Earth Sciences, 2013, 70(1): 145−156 doi: 10.1007/s12665-012-2111-3 [22] 孟红然. 石家庄滹沱河冲洪积扇中部浅层地下水硝酸盐变化特征及趋势[D]. 石家庄: 河北地质大学, 2019MENG H R. Variation characteristics and trend of nitrate in shallow groundwater in the middle of alluvial-diluvial fan of Hutuo River in Shijiazhuang[D]. Shijiazhuang: Hebei GEO University, 2019 [23] MIN L L, SHEN Y J, PEI H W. Estimating groundwater recharge using deep vadose zone data under typical irrigated cropland in the piedmont region of the North China Plain[J]. Journal of Hydrology, 2015, 527: 305−315 doi: 10.1016/j.jhydrol.2015.04.064 [24] 史入宇, 崔亚莉, 赵婕, 等. 滹沱河地区地下水适宜水位研究[J]. 水文地质工程地质, 2013, 40(2): 36−41 doi: 10.16030/j.cnki.issn.1000-3665.2013.02.022SHI R Y, CUI Y L, ZHAO J, et al. A study of the suitable groundwater level of the Hutuo River area[J]. Hydrogeology and Engineering Geology, 2013, 40(2): 36−41 doi: 10.16030/j.cnki.issn.1000-3665.2013.02.022 [25] 张兆吉. 华北平原地下水可持续利用调查评价[M]. 北京: 地质出版社, 2009ZHANG Z J. Investigation and Evaluation of Sustainable Groundwater Utilization in the North China Plain[M]. Beijing: Geology Press, 2009 [26] LI Y S, ZHANG Z J, FEI Y H, et al. Investigation of quality and pollution characteristics of groundwater in the Hutuo River Alluvial Plain, North China Plain[J]. Environmental Earth Sciences, 2016, 75(7): 581 doi: 10.1007/s12665-016-5366-2 [27] ZHANG X W, HE J T, HE B N, et al. Assessment, formation mechanism, and different source contributions of dissolved salt pollution in the shallow groundwater of Hutuo River alluvial-pluvial fan in the North China Plain[J]. Environmental Science and Pollution Research, 2019, 26(35): 35742−35756 doi: 10.1007/s11356-019-06502-2 [28] WANG S Q, WEI S C, LIANG H Y, et al. Nitrogen stock and leaching rates in a thick vadose zone below areas of long-term nitrogen fertilizer application in the North China Plain: a future groundwater quality threat[J]. Journal of Hydrology, 2019, 576: 28−40 doi: 10.1016/j.jhydrol.2019.06.012 [29] 张兆吉, 费宇红. 华北平原地下水可持续利用图集[M]. 北京: 中国地图出版社, 2009ZHANG Z J, FEI Y H. Atlas of Groundwater Sustainable Utilization in North China Plain[M]. Beijing: Sino Maps Press, 2009 [30] 中国地质调查局. 地质云3.0: 全国地下水动态监测数据[DB/OL]. 北京: 中国地质调查局. [2023-03-03]. https://geocloud.cgs.gov.cn/geological/database?type=dzsjk&code=%E6%B0%B4%E6%96%87%E7%8E%AF%E5%9C%B0%E8%B4%A8China Geological Survey. GeoCloud 3.0: National Groundwater Dynamic Monitoring Data[DB/OL]. Beijing: China Geological Survey. [2023-03-03]. https://geocloud.cgs.gov.cn/geological/database?type=dzsjk&code=%E6%B0%B4%E6%96%87%E7%8E%AF%E5%9C%B0%E8%B4%A8 [31] 靳孟贵, 高云福, 王文峰, 等. 用同位素测井技术确定地下水侧向补给量[J]. 水文地质工程地质, 2005, 32(4): 32−36 doi: 10.3969/j.issn.1000-3665.2005.04.009JIN M G, GAO Y F, WANG W F, et al. Determination of lateral groundwater recharge using single well techniques of a radioactive isotope[J]. Hydrogeology and Engineering Geology, 2005, 32(4): 32−36 doi: 10.3969/j.issn.1000-3665.2005.04.009 [32] LU Y T, TANG C Y, CHEN J Y, et al. Spatial characteristics of water quality, stable isotopes and tritium associated with groundwater flow in the Hutuo River alluvial fan plain of the North China Plain[J]. Hydrogeology Journal, 2008, 16(5): 1003−1015 doi: 10.1007/s10040-008-0292-3 [33] CHEN J Y, TANG C Y, SAKURA Y, et al. Spatial geochemical and isotopic characteristics associated with groundwater flow in the North China Plain[J]. Hydrological Processes, 2004, 18(16): 3133−3146 doi: 10.1002/hyp.5753 [34] HUANG X G, PING J H, LENG W, et al. A study on groundwater recharge in the Anyanghe River alluvial fan, North China Plain, based on hydrochemistry, stable isotopes and tritium[J]. Hydrogeology Journal, 2021, 29(6): 2149−2170 doi: 10.1007/s10040-021-02369-1 [35] WANG S Q, YUAN R Q, TANG C Y, et al. Combination of CFCs and stable isotopes to characterize the mechanism of groundwater-surface water interactions in a headwater basin of the North China Plain[J]. Hydrological Processes, 2018, 32(11): 1571−1587 doi: 10.1002/hyp.11494 [36] 刘琰, 乔肖翠, 江秋枫, 等. 滹沱河冲洪积扇地下水硝酸盐含量的空间分布特征及影响因素[J]. 农业环境科学学报, 2016, 35(5): 947−954 doi: 10.11654/jaes.2016.05.019LIU Y, QIAO X C, JIANG Q F, et al. Spatial distribution and influencing factors of nitrate content in groundwater of alluvial-pluvial fan of Hutuo River[J]. Journal of Agro-Environment Science, 2016, 35(5): 947−954 doi: 10.11654/jaes.2016.05.019 [37] 陈肖如, 李晓欣, 胡春胜, 等. 华北平原农田关键带硝态氮存储与淋失量研究[J]. 中国生态农业学报(中英文), 2021, 29(9): 1546−1557CHEN X R, LI X X, HU C S, et al. Nitrate storage and leaching in the critical zone of farmland in the North China Plain[J]. Chinese Journal of Eco-Agriculture, 2021, 29(9): 1546−1557 [38] 赵同科, 张成军, 杜连凤, 等. 环渤海七省(市)地下水硝酸盐含量调查[J]. 农业环境科学学报, 2007, 26(2): 779−783 doi: 10.3321/j.issn:1672-2043.2007.02.072ZHAO T K, ZHANG C J, DU L F, et al. Investigation on nitrate concentration in groundwater in seven provinces (city) surrounding the Bo-Hai Sea[J]. Journal of Agro-Environment Science, 2007, 26(2): 779−783 doi: 10.3321/j.issn:1672-2043.2007.02.072 [39] WANG S Q, ZHENG W B, CURRELL M, et al. Relationship between land-use and sources and fate of nitrate in groundwater in a typical recharge area of the North China Plain[J]. Science of the Total Environment, 2017, 609: 607−620 doi: 10.1016/j.scitotenv.2017.07.176 [40] HUANG P, ZHANG J B, ZHU A N, et al. Nitrate accumulation and leaching potential reduced by coupled water and nitrogen management in the Huang-Huai-Hai Plain[J]. Science of the Total Environment, 2018, 610: 1020−1028 [41] ZHENG W B, WANG S Q, SPRENGER M, et al. Response of soil water movement and groundwater recharge to extreme precipitation in a headwater catchment in the North China Plain[J]. Journal of Hydrology, 2019, 576: 466−477 doi: 10.1016/j.jhydrol.2019.06.071 [42] ZHENG W B, WANG S Q. Extreme precipitation accelerates the contribution of nitrate sources from anthropogenetic activities to groundwater in a typical headwater area of the North China Plain[J]. Journal of Hydrology, 2021, 603: 127110 doi: 10.1016/j.jhydrol.2021.127110 -