Monitoring method of salt ion content in salinized soil based on hyperspectral technology

Abstract

The invention discloses a method for monitoring the content of salt ions in salinized soil based on hyperspectral technology, which includes the following main steps: (1) collecting soil samples in the field and performing pretreatment; (2) drying and drying the soil samples (3) Determining the total salt and eight major salt ions on the soil sample; (4) Conducting hyperspectral measurement on the soil sample, and obtaining the original spectral reflectance characteristic curve of the sample; (5) Numerical processing of the original spectrum, and Correlation analysis was carried out on the measured salt ion content; (6) The support vector machine model construction method was introduced to carry out model construction and accuracy evaluation on the screened spectral transformation forms. The method of the invention has high prediction accuracy for the content of each salt ion in the soil, and the method provides a new way for the indoor determination of the content of the salt ion in the salinized soil, and also realizes the rapid and non-destructive monitoring of the types of regional soil salinization hazards provide new means.

Description

technical field [0001] The invention relates to the field of rapid monitoring of soil salinity, in particular to a hyperspectral technology-based monitoring method for salt ion content in salinized soil. Background technique [0002] Due to the joint effects of its soil parent material, topography, climate conditions and human factors, soil salinization and secondary salinization are seriously endangered in Xinjiang. This kind of land has low productivity, fragile ecology and harsh environment. The bottleneck of ecological construction. [0003] With the continuous development of remote sensing technology and image processing technology, the use of remote sensing has become the main means of soil salinization monitoring. Traditional soil salinization monitoring adopts field soil fixed-point survey method, which is not only time-consuming and laborious, but also has few measuring points and poor representativeness, which makes it impossible to realize large-scale real-time m...

AI Technical Summary

Problems solved by technology

[0007] (1) In the process of effectively extracting soil attribute information using hyperspectral technology, there is no good comparison of soil water content. Often, when measuring soil spectral information, the air-drying method is used based on experience or some existing research results. It is unclear whether the hyperspectral quantitative inversion of salt ions can be performed with fresh soil or dried

[0008] (2) As the soil particle size decreases, the reflectance of the soil surface increases, resulting in a decrease in the depth of the absorption peak, and the relationship between the spectral features of different bands and soil properties will change. Usually, soil spectra are measured using The 2mm sieve, whether other particle size treatments will improve the fitting accuracy in the determination of soil salt segregation remains to be further studied

[0009] (3) Indoor hyperspectral analysis technology can be widely used in the environmental assessment of soil resources because its influencing factors are easier to control than those in the field. The incident angle of indoor simulated light source has a significant impact on the hyperspectral measurement of soil properties, which may lead to different incident angles of light sources. There is no sharing of hyperspectral data among them. Therefore, the incident angle of the light source for the hyperspectral determination of soil salt ions is a problem that must be solved.

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