멀티스펙트랄 이미지 센서를 이용한 전자 지도 기반 변량 질소 살포

Abstract

Site-specific N application for corn is one of the most commonly used precision crop managements in USA. To implement the site-specific N application, various nitrogen stress sensing methods, including aerial image, tissue analysis, soil sampling analysis, and SPAD meter readings, have been used. Use of side-dressing, an efficient nitrogen application method than a uniform application in either late fall or early spring, relies mainly on the capability of detecting nitrogen deficiency. This paper presents a map-based variable rate nitrogen application using a multi-spectral corn nitrogen deficiency (CND) sensor. This sensor assess the nitrogen stress by means of the estimated SPAD reading calculated from the corn leave reflectance. The estimated SPAD value from the CND sensor system and location information form DGPS of each field block were combined into a field map using the ArcView program. Then this map was converted into a raster file for a map-based variable rate application software. The relative SPAD (RSPAD = SPAD over reference SPAD) was investigated 2 weeks after the map-based variable rate nitrogen application. The results showed that the map-based variable rate application system was feasible.