This study aims to determine the total nitrogen content (TNC) in soils in Tuoketuo County quickly and nondestructively, thus meeting the requirements of precision agriculture. With the soil TNC and hyperspectral data of 120 sampling sites in the study area as the data source, this study processed the hyperspectral data using the 1~2 orders fractional order differential (FOD) interval of 0.1 to screen the sensitive wavebands. Then, this study built 24 inversion models for soil TNC using the support vector machine (SVM) and the back propagation neural network (BPNN). The results are as follows: ① After FOD processing, the information at the wave crests and troughs of the spectra was amplified, and the reflectance of the remaining wavebands approached zero gradually with an increase in the decomposition scale. ② The Pearson correlation coefficient between original spectra and soil TNC was r = 0.61. This correlation coefficient was up to a maximum of 0.67 at 1.1- order after FOD processing, increasing by 0.06. ③ The BPNN prediction models outperformed the SVM prediction models. The optimal soil TNC prediction model was the BPNN model built after 1.1-order differential processing. This model yielded an R2 of 0.75 and a root mean square error (RMSE) of 0.16 for the modeling set and an R2 of 0.71 and an RMSE of 0.16 for the verification set, with a relative percent deviation (RPD) of 2.06. This model produced effective inversion results of the soil TNC in the study area, with a much higher accuracy than the BPNN model built using original spectra. Therefore, the BPNN model built using hyperspectral data through 1.1-order differential processing allows for the inversion-based prediction of soil TNC in the study area, providing a theoretical reference and technical support for local precision agriculture.
陈昊宇, 项磊, 高贺, 牟金燚, 索晓晶, 滑博伟. 基于分数阶微分的土壤全氮高光谱反演[J]. 自然资源遥感, 2023, 35(3): 170-178.
CHEN Haoyu, XIANG Lei, GAO He, MU Jinyi, SUO Xiaojing, HUA Bowei. Hyperspectral inversion of total nitrogen content in soils based on fractional order differential. Remote Sensing for Natural Resources, 2023, 35(3): 170-178.
Wang W C, Yang W, Cui Y L, et al. Prediction of soil total nitrogen based on CatBoost algorithm and fusion of image spectral features[J]. Transactions of the Chinese Society of Agricultural Machinery, 52(s1):316-322.
Yin C Y, Bai Z J, Luo D F, et al. Comparative study on estimation models of soil total nitrogen content based on hyperspectral data[J]. Soil and Fertilizer Sciences in China, 2022(1):9-15.
Zhong H, Li X C, Zhai H R, et al. Indirect estimation of organic matter content in plough layer based on topsoil spectrum[J]. Journal of Anhui Agricultural University, 2020, 47(3):421-426.
Wang Y C, Yang X F, Zhao Q C, et al. Quantitative inversion of soil organic matter content in northern tidal soil by binary wavelet technique[J]. Spectroscopy and Spectral Analysis, 2019, 39(9):2855-2861.
doi: 10.3964/j.issn.1000-0593(2019)09-2855-07
[5]
Dalai R C, Henry R J. Simultaneous determination of moisture,organic carbon,and totalnitrogen by in France spectrometry[J]. Soil Science Society of America Journal, 1986, 50:120-123.
doi: 10.2136/sssaj1986.03615995005000010023x
[6]
Hummel J W, Sudduth K A, Hollinger S E. Soil moisture and organic matter prediction of surface and subsurface soils using an NIR soil sensor[J]. Computers and Electronics in Agriculture, 2001, 32(2):149-165.
doi: 10.1016/S0168-1699(01)00163-6
[7]
Reeves J B, Mccarty G W, Meisinger J J. Near infrared reflectance spectroscopy for the analysis of agricultural soil[J]. Journal of Near Infrared Spectroscopy, 1997, 7(3):179-193.
doi: 10.1255/jnirs.248
Lu Y L, Bai Y L, Wang L, et al. Hyperspectral prediction analysis of total nitrogen content in black soil[J]. Transactions of the Chinese Society of Agricultural Engineering, 2010, 26(1):256-261.
Zhang J J, Tian Y C, Yao X, et al. Estimating soil total nitrogen content based on hyperspectral analysis technology[J]. Journal of Natural Resources, 2011, 26(5):881-890.
doi: 10.11849/zrzyxb.2011.05.015
Zhao Y D, Pi T T. Spectral prediction model of total nitrogen content of clay loam in Beijing[J]. Trasactions of the Chinese Society of Agricaltrual Machinery, 2016, 47(3):144-149.
Wang S D, Shi P J, Zhang H B, et al. Inversion of soil total nitrogen content in reclaimed farmland of mining area based on hyperspectral imaging[J]. Chinese Journal of Ecology, 2019, 38(1):294-301.
Zhao Q D, Ge X Y, Ding J L, et al. Combination fractional order differential and machine learning algorithm for spectral estimation of soil organic carbon content[J]. Laser and Optoelectronics Progress, 2020, 57(15):253-261.
Li W Y, Mamat S, Maihemuti B. Hyperspectral inversion of soil organic matter content based on fractional differential[J]. Laser and Optoelectronics Progress, 2023, 60(7):404-411.
Jing X, Zhang T, Zou Q, et al. Construction of remote sensing monitoring model of wheat stripe rust based on fractional differential spectral index[J]. Transactions of the Chinese Society of Agricultural Engineering, 2021, 37(17):142-151.
Zhao H, Li X G, Jin W G, et al. Hyperspectral estimation of soil conductivity in oasis along Bosten Lake based on fractional differential[J]. Journal of Gansu Agricultural University, 2021, 56(1):118-125.
Tian A H, Zhao J S, Zhang S J, et al. Hyperspectral estimation of electrical conductivity of saline soil based on fractional differentiation[J]. Chinese Journal of Eco-Agriculture, 2020, 28(4):599-607.
[17]
Wang X P, Zhang F, Kung H T, et al. New methods for improving the remote sensing estimation of soil organic matter content (SOMC) in the Ebinur Lake Wetland National Nature Reserve (ELWNNR) in northwest China[J]. Remote Sensing of Environment, 2018, 218:104-118.
doi: 10.1016/j.rse.2018.09.020
Lu Z H, Liu X Y, Chang S J, et al. Hyperspectral inversion of the surface soil N/P rationin a grassland mining area based on the BP network[J]. Pratacultural Science, 2018, 35(9):2127-2136.
Tan N, Sun Y D, Wang X S, et al. Research on near infrared spectrum with principal component analysis and support vector machine for timber identification[J]. Spectroscopy and Spectral Analysis, 2017, 37(11): 3370-3374.
Zhu W J, Mao H P, Zhou Y, et al. Nitrogen nutrition diagnosis of tomato leaves based on hyperspectral image technology[J]. Journal of Jiangsu University (Natural Science Edition), 2014, 35(3): 290-294.
Dong Y, Cheng W, Zhang Y P, et al. The method of classification and regression based on SVM and its application in yield prediction[J]. Journal of Computer Applications, 2010, 30(9):2310-2313.
doi: 10.3724/SP.J.1087.2010.02310
Guo Y K, Liu N, Liu L, et al. Hyper-spectral inversion of soil Cu content based on BP neural network model[J]. Science of Surveying and Mapping, 2018, 43(1):135-139,152.
[23]
Pan H, Wang X Y, Chen Q, et al. Application of BP neural network based on genetic algorithm[J]. Computer Applications, 2005, 25(12):2777-2779.
Liu R, Zhang S L, Hou H P, et al. Hyperspectral retrieval of chlorophyll content in soybean leaves based on mind evolutionary optimization BP neural network[J]. Jiangsu Agricultural Sciences, 2018, 46(13):212-216.
Chen H Y, Yang G, Han X Y, et al. Hyperspectral inversion of soil organic matter content based on continuous wavelet transform[J]. China Agricultural Science and Technology Guide, 2021, 23(5):132-142.
Liu Y, Feng H K, Sun Q, et al. Estimation of potato above-groud biomass based on fractional differential of UAV hyperspectral[J]. Transactions of the Chinese Society of Agricultural Machinery, 2020, 51(12):202-211.
[27]
徐彬彬. 土壤剖面的反射光谱研究[J]. 土壤, 2000(6): 281-287.
Xu B B. Study on the reflection spectrum of soil profile[J]. Soil, 2000(6):281-287.
Liu F, Ma L, Yang G, et al. Hyperspectral characteristic analysis and estimation of total nitrogen content in grey desert soil[J]. Xinjiang Agricultural Sciences, 2017, 54(1):140-147.
Shao L B, Chen Y Y, Xu L, et al. Analysis on soil moisture content hyperspectral response and construction of estimation model based on fractional-order derivative[J]. Surveying and Mapping Geographic Information, 2022, 47(s1):131-136.
Li C C, Shi J J, Ma C Y, et al. Estimation of chlorophyll content in winter wheat based on wavelet transform and fractional differential[J]. Transactions of the Chinese Society of Agricultural Machinery, 2021, 52(8):172-182.