Groundwater Flow Processes and Human Impact along the Arid US-Mexican Border, Evidenced by Environmental Tracers: The Case of Tecate, Baja California
Abstract
:1. Introduction
2. Study Area
3. Materials and Methods
3.1. Field Work and Laboratory
3.2. Interpretation
4. Results
4.1. Chemical Characterization
4.2. Hydrochemical Clusters
4.3. Statistical Variation of Selected Variables
4.4. Identification of Hydrogeochemical Processes
4.5. Geochemical Trends
4.6. Stable Isotopes
4.7. Groundwater Age
5. Discussion
6. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Well ID | Temp | pH | EC | OD | Na | K | Ca | Mg | HCO3 | Cl | SO4 | NO3 | F | Sr | Fe | Si | Charge Balance Error | 18O | 2H | 3H | 13C | 14C |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
(-) | (°C) | (std. Unit) | (µS cm−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (mg L−1) | (%) | (‰) | (‰) | (TU) | (‰) | (pMC) |
1 | 19.9 | 7.7 | 706 | 5.0 | 76.1 | 2.5 | 56.1 | 23.8 | 414.3 | 65.1 | 31.3 | 1.0 | <0.5 | 0.264 | 0.010 | 9.2 | −6.8 | −6.84 | −46.47 | 2.2 | −13.0 | 107.2 |
2 | 20.5 | 7.9 | 1111 | 7.2 | 149.0 | 6.0 | 61.6 | 37.4 | 604.8 | 123.5 | 56.2 | 6.6 | 0.7 | 0.422 | 0.010 | 10.2 | −6.8 | −6.40 | −43.75 | --- | --- | --- |
3 | 18.7 | 7.8 | 1323 | 6.7 | 179.2 | 5.7 | 83.9 | 40.6 | 444.7 | 146.1 | 130.4 | 5.5 | 0.6 | 0.550 | 0.010 | 17.3 | 4.7 | −6.50 | −43.94 | 2.8 | −13.4 | 104.0 |
4 | 21.2 | 7.8 | 835 | 7.3 | 79.0 | 6.1 | 68.7 | 28.5 | 305.7 | 90.7 | 75.4 | 3.4 | <0.5 | 0.278 | 0.010 | 22.7 | 1.0 | −6.16 | −42.51 | --- | --- | --- |
5 | 20.4 | 7.5 | 1738 | 5.5 | 199.1 | 5.3 | 131.8 | 65.1 | 587.9 | 163.0 | 275.3 | 4.5 | <0.5 | 0.761 | 0.010 | 19.5 | 1.9 | −7.12 | −50.20 | --- | --- | --- |
6 | 21.8 | 7.7 | 1351 | 3.8 | 154.9 | 5.4 | 102.5 | 44.2 | 376.4 | 146.9 | 182.1 | 10.3 | <0.5 | 0.524 | 0.010 | 21.6 | 5.2 | −6.69 | −47.75 | 2.7 | −14.2 | 100.8 |
7 | 18.4 | 7.8 | 1860 | 6.6 | 268.6 | 4.4 | 103.7 | 52.7 | 646.9 | 280.3 | 139.2 | 2.3 | <0.5 | 0.626 | 0.010 | 20.7 | −0.5 | −6.54 | −44.94 | 1.8 | −13.4 | 98.4 |
8 | 19.8 | 7.8 | 1594 | 5.3 | 190.9 | 7.0 | 111.5 | 50.4 | 533.1 | 220.8 | 121.8 | 1.9 | <0.5 | 0.418 | 0.010 | 16.3 | 1.7 | −6.75 | −47.20 | 2.1 | −13.8 | 97.3 |
9 | 21.2 | 7.3 | 1907 | 7.9 | 202.9 | 4.8 | 134.1 | 78.5 | 681.9 | 251.5 | 145.5 | 22.2 | <0.5 | 0.841 | 0.010 | 22.0 | 1.6 | −6.90 | −47.92 | --- | --- | --- |
10 | 19.2 | 7.8 | 1332 | 4.3 | 164.8 | 4.4 | 85.1 | 41.9 | 405.7 | 140.5 | 140.1 | 12.9 | 0.6 | 0.589 | 0.010 | 19.4 | 4.8 | −6.86 | −47.57 | --- | --- | --- |
13 | 19.7 | 7.5 | 1319 | 5.3 | 170.2 | 4.2 | 83.0 | 40.8 | 459.1 | 160.6 | 147.6 | 12.8 | 0.6 | 0.562 | 0.010 | 18.9 | −1.0 | −6.84 | −47.80 | --- | --- | --- |
14 | 17.6 | 8.6 | 1525 | 13.1 | 200.8 | 6.4 | 98.5 | 39.4 | 250.9 | 178.3 | 302.2 | 0.3 | 0.4 | 1.262 | 0.013 | 5.2 | 4.9 | −10.30 | −88.04 | 7.4 | −8.7 | 90.6 |
15 | 15.6 | 7.0 | 437 | 9.2 | 43.1 | 3.5 | 28.1 | 12.2 | 162.5 | 34.0 | 28.1 | 18.2 | <0.5 | 0.238 | 0.010 | 13.3 | −0.3 | −7.45 | −48.98 | 2.2 | −15.8 | 96.0 |
16 | 13.6 | 7.9 | 1070 | 5.3 | 125.2 | 5.1 | 77.0 | 25.5 | 503.1 | 109.2 | 12.6 | 0.2 | 0.3 | 0.826 | 0.065 | 10.9 | −1.2 | −6.60 | −46.88 | 1.8 | −12.6 | 101.7 |
17 | 19.4 | 7.7 | 1189 | 8.3 | 121.9 | 2.6 | 85.0 | 30.1 | 303.4 | 140.7 | 71.4 | 35.5 | 0.4 | 0.651 | 0.010 | 26.8 | 6.6 | −7.15 | −48.88 | --- | --- | --- |
18 | 18.6 | 7.7 | 1299 | 10.8 | 136.5 | 2.5 | 102.8 | 35.5 | 445.3 | 151.3 | 100.2 | 8.2 | 0.6 | 0.682 | 0.010 | 19.7 | 0.6 | −8.25 | −60.33 | 2.3 | −14.2 | 103.5 |
19 | 17.3 | 7.8 | 854 | 11.8 | 197.4 | 7.2 | 117.8 | 35.5 | 795.7 | 95.6 | 31.0 | 10.1 | <0.5 | 0.457 | 0.010 | 9.0 | 2.8 | −7.54 | −51.83 | 1.9 | −13.6 | 107.4 |
20 | 18.9 | 7.9 | 637 | 10.8 | 71.3 | 2.7 | 48.9 | 13.0 | 288.2 | 50.5 | 21.6 | 12.3 | <0.5 | 0.439 | 0.010 | 10.2 | −1.4 | −7.54 | −51.35 | 1.8 | −12.5 | 108.8 |
24 | 20.3 | 7.4 | 2350 | 2.8 | 307.8 | 2.4 | 132.1 | 74.8 | 447.6 | 317.6 | 409.4 | 0.2 | 0.8 | 0.030 | 0.180 | 16.3 | 2.3 | −8.82 | −72.73 | 5.5 | −14.7 | 102.2 |
25 | 18.4 | 7.4 | 664 | 7.3 | 74.9 | 2.9 | 42.3 | 12.5 | 214.0 | 86.2 | 28.5 | 2.1 | <0.5 | 0.051 | 0.010 | 22.0 | −2.8 | −7.92 | −56.76 | <0.5 | −13.3 | 98.9 |
26 | 15.8 | 7.6 | 1655 | 5.2 | 253.3 | 4.8 | 75.7 | 24.7 | 421.1 | 178.5 | 118.6 | 28.6 | 2.2 | 0.110 | 0.010 | 19.4 | 7.3 | −7.67 | −54.40 | 1.0 | −13.3 | 102.6 |
27 | 16.6 | 7.4 | 767 | 5.8 | 92.7 | 1.3 | 57.1 | 16.1 | 286.6 | 104.0 | 29.4 | 0.2 | 0.6 | 0.086 | 0.019 | 18.9 | −2.1 | −7.62 | −51.65 | <0.9 | −14.8 | 95.7 |
28 | 14.4 | 7.7 | 616 | 6.1 | 81.9 | 2.0 | 37.9 | 12.7 | 293.0 | 75.6 | 27.7 | 1.6 | <0.5 | 0.058 | 0.023 | 13.3 | −9.3 | −7.51 | −51.60 | 2.2 | −13.6 | 101.3 |
29 | 17.9 | 7.6 | 508 | 5.2 | 50.4 | 2.3 | 37.7 | 13.0 | 248.9 | 41.8 | 13.8 | 5.6 | <0.5 | 0.022 | 0.010 | 10.9 | −6.5 | −7.15 | −49.04 | 1.5 | −15.3 | 107.3 |
32 | 17.9 | 7.1 | 967 | 5.0 | 115.8 | 2.4 | 46.0 | 25.9 | 200.5 | 118.0 | 150.9 | 0.5 | <0.5 | 0.039 | 0.026 | 20.6 | −3.3 | −6.29 | −47.64 | 1.8 | −15.5 | 101.2 |
33 | 16.1 | 7.7 | 7480 | 5.8 | 747.6 | 185.6 | 374.3 | 247.7 | 1238.7 | 1584.4 | 574.8 | 15.8 | <0.5 | 0.002 | 0.078 | 18.7 | −0.7 | −5.83 | −47.67 | 2.2 | −10.2 | 106.1 |
Year | Measures | CE (µS/cm) | pH | Ca (mg L−1) | Mg (mg L−1) | Na (mg L−1) |
1981 | Avg. ± St.dev. | 1122 ± 739 | 8.1 ± 0.4 | 51.3 ± 16.6 | 40.6 ± 33.2 | 138.3 ± 139.5 |
2014 | Avg. ± St.dev. | 1622 ± 1642 | 7.6 ± 0.3 | 103.0 ± 79.4 | 49.3 ± 56.7 | 193.0 ± 163.3 |
p-value | 0.001 * | 0.001 * | 0.021 * | 0.584 | 0.269 | |
K (mg L−1) | Cl (mg L−1) | HCO3 (mg L−1) | SO4 (mg L−1) | NO3 (mg L−1) | ||
1981 | Avg. ± St.dev. | 4.3 ± 2.1 | 175.9 ± 184.7 | 207.6 ± 45.6 | 159.0 ± 205.7 | 7.2 ± 6.3 |
2014 | Avg. ± St.dev. | 15.2 ± 45.5 | 232.5 ± 367.1 | 472.7 ± 261.6 | 151.5 ± 161.6 | 8.8 ± 11.1 |
p-value | 0.346 | 0.577 | 0.001 * | 0.887 | 0.640 |
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Mahlknecht, J.; Daessle, L.W.; Esteller, M.V.; Torres-Martinez, J.A.; Mora, A. Groundwater Flow Processes and Human Impact along the Arid US-Mexican Border, Evidenced by Environmental Tracers: The Case of Tecate, Baja California. Int. J. Environ. Res. Public Health 2018, 15, 887. https://doi.org/10.3390/ijerph15050887
Mahlknecht J, Daessle LW, Esteller MV, Torres-Martinez JA, Mora A. Groundwater Flow Processes and Human Impact along the Arid US-Mexican Border, Evidenced by Environmental Tracers: The Case of Tecate, Baja California. International Journal of Environmental Research and Public Health. 2018; 15(5):887. https://doi.org/10.3390/ijerph15050887
Chicago/Turabian StyleMahlknecht, Jürgen, Luis Walter Daessle, Maria Vicenta Esteller, Juan Antonio Torres-Martinez, and Abrahan Mora. 2018. "Groundwater Flow Processes and Human Impact along the Arid US-Mexican Border, Evidenced by Environmental Tracers: The Case of Tecate, Baja California" International Journal of Environmental Research and Public Health 15, no. 5: 887. https://doi.org/10.3390/ijerph15050887