Prediction of Soil Available Boron Content in Visible-Near-Infrared Hyperspectral Based on Different Preprocessing Transformations and Characteristic Wavelengths Modeling

Table 10

Characteristic wavelengths selected by RFA and VIP in MSC/BPNN modeling.

Variable selection method	No. of variables	Characteristic wavelengths (nm)
RFA	328	538, 456, 466, 510, 464, 548, 535, 525, 513, 458, 460, 529, 465, 905, 463, 519, 518, 527, 520, 526, 498, 522, 530, 515, 528, 1654, 1653, 461, 521, 1248, 524, 523, 508, 769, 455, 1367, 1655, 545, 517, 871, 1429, 509, 758, 825, 1428, 879, 547, 1432, 1215, 734, 475, 900, 495, 555, 536, 532, 1369, 895, 539, 747, 549, 1298, 552, 546, 540, 1376, 551, 1430, 593, 457, 859, 858, 1371, 1433, 813, 828, 925, 554, 1295, 756, 1427, 507, 733, 760, 862, 1294, 736, 543, 752, 909, 1375, 1368, 502, 762, 560, 1292, 904, 906, 558, 917, 499, 732, 1434, 1651, 1361, 902, 586, 869, 494, 1553, 504, 449, 972, 516, 888, 1378, 583, 469, 759, 503, 588, 533, 450, 896, 876, 563, 512, 908, 1297, 749, 459, 916, 541, 497, 913, 1550, 1296, 1370, 605, 584, 891, 531, 912, 1394, 1282, 462, 610, 1249, 570, 550, 907, 1406, 1396, 779, 578, 514, 557, 1379, 882, 511, 746, 860, 1372, 924, 569, 1374, 814, 829, 1307, 923, 1431, 1250, 500, 1548, 1397, 454, 534, 777, 1395, 1513, 1435, 1156, 1547, 1363, 1365, 1549, 362, 1321, 830, 1437, 897, 448, 585, 901, 764, 992, 792, 875, 809, 914, 915, 490, 1648, 435, 893, 964, 1647, 492, 377, 1384, 1343, 726, 1596, 741, 1318, 1649, 968, 1381, 1151, 1499, 967, 710, 1642, 892, 870, 778, 865, 739, 486, 955, 1645, 1597, 1290, 1602, 872, 971, 864, 445, 982, 1650, 472, 745, 1225, 911, 1546, 1511, 833, 899, 594, 470, 1205, 885, 974, 1239, 1323, 921, 918, 1617, 350, 919, 1505, 844, 1284, 1345, 1561, 748, 1300, 1209, 1552, 1545, 744, 849, 1612, 1634, 1226, 981, 1149, 654, 1256, 1551, 1402, 1508, 883, 451, 672, 1506, 1652, 774, 1637, 670, 831, 474, 1605, 763, 440, 878, 1353, 1216, 1644, 958, 773, 880, 447, 1299, 384, 1041, 650, 1537, 381, 1393, 1482, 1266, 704, 866, 423, 367, 1313, 785, 988, 1415, 653, 963, 1144, 943, 481, 1019, 1598, and 783.
VIP	108	872, 1297, 1248, 1296, 860, 1298, 891, 875, 1295, 1403, 905, 859, 1404, 839, 861, 1402, 862, 1294, 883, 864, 847, 458, 1293, 1401, 871, 895, 741, 1644, 1645, 888, 1405, 853, 863, 1594, 825, 457, 1292, 1593, 1299, 460, 893, 1646, 461, 462, 1400, 1643, 455, 858, 1595, 769, 451, 464, 892, 909, 459, 1592, 1291, 456, 848, 813, 1647, 450, 449, 749, 908, 1290, 1399, 866, 844, 1591, 752, 833, 784, 1596, 851, 1289, 454, 822, 857, 964, 1648, 1551, 963, 947, 1642, 1552, 738, 1550, 1288, 840, 965, 771, 463, 1398, 465, 946, 760, 962, 1553, 1406, 843, 1287, 1590, 736, 466, 1649, 453, and 1549.