The purpose of the study is to develop the method for detecting bare fallows by ground-based remote and satellite data during growing season of 2018. The objects of the study are bare fallows and wheat crops on the territory of the Krasnoyarsk RIA FRC KSC SB RAS near the village of Minino (Krasnoyarsk Territory). When conducting ground- based spectrometry of the test sites studied, a field- based spectrometry complex was used, consisting of Spectral Evolution PSR-1100F portable spectroradiometer, a computer, a calibration reflect- ing standard, a digital camera, and software. As a result of ground-based spectrometry, reflective spectral properties of bare fallows and wheat crops were studied, which are commonly expressed by spectral brightness coefficient (SBC). The spectral brightness coefficient of objects in the range from 320 to 1100 nm was measured. Sentinel-2B satel- lite information was used to interpret bare fallows and wheat crops. On the basis of ground and satel- lite data the spectral indices were calculated: NDVI(Normalized Difference Vegetation Index) and NDSI (Normalized Difference Soil Index). According to the results of ground-based spectrometry, it was shown that, during growing season, bare fallows and grain crops differed in optical characteristics. Based on the analysis of satellite data on the dy- namics of NDVI vegetation index and NDSI soil index, the possibility of identifying bare fallows and precise time control for plowing bare fallows during the vegetation season was shown. On studied bare fallows, the dates of plowing were well recognized (July, 10 and 25) - NDVI index sharply decreased from 0.4 (sparse vegetation) to 0.05 (bare soil). At the same time, on plowing dates, the value of the NDSI soil index increased. The applicability of NDSI soil index for the identification of bare fallows was shown.
remote sensing, ground-based spectrometry, spectral brightness coefficient, satel- lites
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