[1] [1] Song X Z, Gu H H, Wang M, et al. Scientific Reports, 2016, 6(1): 24107.

[2] [2] Liu J, Appiah-Sefah G, Apreku T O. Water Science and Engineering, 2018, 11(1): 39.

[3] [3] Zhang J B, Lv J H, Li Q, et al. Biogeochemistry, 2017, 134(1-2): 115.

[4] [4] Zhang T A, Chen H Y H, Ruan H. Ismejouranl, 2018, 12(7): 1817.

[5] [5] Sainju U M, Singh H P, Singh B P. Pedosphere, 2017, 27(2): 223.

[6] [6] Houlton B Z, Wang Y P, Vitousek P M, et al. Nature, 2008, 7202(454): 327.

[7] [7] Houlton B Z, Morford S L, Dahlgren R A. Science, 2018, 360(6384): 58.

[8] [8] Morford S L, Houlton B Z, Dahlgren R A. Nature, 2011, 477(7362): 78.

[11] [11] Zhang C, Liu S F, Ye F W, et al. Journal of Applied Remote Sensing, 2019, 13(1): 14524.

[13] [13] Yang H M, Qiu J T, Yu L, et al. Studies in Conservation, 2019, 64(2): 63.

[14] [14] Qiu J T, Qiu L, Mu H X, et al. Geoheritage, 2019, 11(3): 1027.

[15] [15] Qiu J T, Qi H, Duan J L. Minerals, 2017, 7(1): 3.

[16] [16] Qiu J T, Zhang C, Hu X. Remote Sensing, 2015, 7: 13878.

[17] [17] Qiu J T, Li P J, Yu Z F, et al. Geoheritage, 2015, 7(4): 307.

[18] [18] Xu Q J, Liu S F, Ye F W, et al. International Journal of Remote Sensing, 2018, 39: 453.

[19] [19] Xu Q J, Ye F W, Liu S F, et al. Remote Sensing, 2017, 9: 451.

[20] [20] Qiu J T, Zhang C, Xu Q J, et al. Remote Sensing Letters, 2017, 8: 859.

[21] [21] Eisele A, Chabrillat S, Hecker C, et al. Remote Sensing of Environment, 2015, 163: 296.