Research Article
Fluorescence Spectroscopy and 13C NMR Spectroscopy Characteristics of HA in Black Soil at Different Corn Straw Returning Modes
Table 4
Excitation (Ex)/emission (Em) wavelength and fluorescence intensity (FI) of peaks in humic acid after different corn straw return modes.
| | Soil depth (cm) | Treatment | Peak A | Peak B | Peak C | | Ex/Em | Intensity (a.u.) | Ex/Em | Intensity (a.u.) | Ex/Em | Intensity (a.u.) |
| | 0∼20 | CK | 460/524 | 115.02 | 370/504 | 105.00 | 290/503 | 117.84 | | SCR | 460/531 | 154.52 | 370/523 | 136.33 | 290/508 | 153.54 | | MBR | 460/523 | 149.63 | 370/498 | 135.81 | 290/521 | 141.71 | | SEDI | 460/528 | 130.56 | 370/495 | 117.72 | 290/523 | 129.32 | | 20∼40 | CK | 460/528 | 112.86 | 370/511 | 112.61 | 290/515 | 114.30 | | SCR | 460/529 | 125.33 | 370/493 | 114.19 | 290/520 | 120.14 | | MBR | 460/537 | 144.73 | 370/505.6 | 126.12 | 300/522 | 135.99 | | SEDI | 460/535 | 172.34 | 370/506 | 143.47 | 290/509 | 164.00 |
|
|
Note. CK: no straw application; SCR: straw mulching; MBR: straw deep ploughing; SEDI: straw enrichment and deep incorporation.
|
