Next Article in Journal
A Total Bounded Variation Approach to Low Visibility Estimation on Expressways
Next Article in Special Issue
Specim IQ: Evaluation of a New, Miniaturized Handheld Hyperspectral Camera and Its Application for Plant Phenotyping and Disease Detection
Previous Article in Journal
The Effect of Zeolite Composition and Grain Size on Gas Sensing Properties of SnO2/Zeolite Sensor
Previous Article in Special Issue
Plant Pest Detection Using an Artificial Nose System: A Review
Open AccessArticle

Research on the Effects of Drying Temperature on Nitrogen Detection of Different Soil Types by Near Infrared Sensors

by Pengcheng Nie 1,2,3, Tao Dong 1,2, Yong He 1,2,* and Shupei Xiao 1,2
College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
Key Laboratory of Sensors Sensing, Ministry of Agriculture, Zhejiang University, Hangzhou 310058, China
State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310058, China
Author to whom correspondence should be addressed.
Sensors 2018, 18(2), 391;
Received: 7 December 2017 / Revised: 5 January 2018 / Accepted: 22 January 2018 / Published: 29 January 2018
(This article belongs to the Special Issue Sensors in Agriculture)
Soil is a complicated system whose components and mechanisms are complex and difficult to be fully excavated and comprehended. Nitrogen is the key parameter supporting plant growth and development, and is the material basis of plant growth as well. An accurate grasp of soil nitrogen information is the premise of scientific fertilization in precision agriculture, where near infrared sensors are widely used for rapid detection of nutrients in soil. However, soil texture, soil moisture content and drying temperature all affect soil nitrogen detection using near infrared sensors. In order to investigate the effects of drying temperature on the nitrogen detection in black soil, loess and calcium soil, three kinds of soils were detected by near infrared sensors after 25 °C placement (ambient temperature), 50 °C drying (medium temperature), 80 °C drying (medium-high temperature) and 95 °C drying (high temperature). The successive projections algorithm based on multiple linear regression (SPA-MLR), partial least squares (PLS) and competitive adaptive reweighted squares (CARS) were used to model and analyze the spectral information of different soil types. The predictive abilities were assessed using the prediction correlation coefficients (RP), the root mean squared error of prediction (RMSEP), and the residual predictive deviation (RPD). The results showed that the loess (RP = 0.9721, RMSEP = 0.067 g/kg, RPD = 4.34) and calcium soil (RP = 0.9588, RMSEP = 0.094 g/kg, RPD = 3.89) obtained the best prediction accuracy after 95 °C drying. The detection results of black soil (RP = 0.9486, RMSEP = 0.22 g/kg, RPD = 2.82) after 80 °C drying were the optimum. In conclusion, drying temperature does have an obvious influence on the detection of soil nitrogen by near infrared sensors, and the suitable drying temperature for different soil types was of great significance in enhancing the detection accuracy. View Full-Text
Keywords: nitrogen; near infrared sensors; drying temperature; SPA-MLR; PLS; CARS nitrogen; near infrared sensors; drying temperature; SPA-MLR; PLS; CARS
Show Figures

Figure 1

MDPI and ACS Style

Nie, P.; Dong, T.; He, Y.; Xiao, S. Research on the Effects of Drying Temperature on Nitrogen Detection of Different Soil Types by Near Infrared Sensors. Sensors 2018, 18, 391.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

Back to TopTop