A Study of the Effects of Soil Salinity on the Growth and Development of Maize (Zea Mays L.) by using Sentinel-2 Imagery

Abstract

Salinization of soil cover and the constant increase in their area have become one of the most pressing problems year after year for irrigated agriculture regions. The degradation processes caused by the salinity of soils negatively affect the growth and development of food crops. Therefore, this study focused on the effects of soil salinity in the midstream of the Syrdarya on the growth and development of maize where the climate is continental and mostly arid, and the cultivation of crops is possible under irrigation conditions. The study made harmonious use of remote sensing and field survey methods based on modern and traditional approaches in terms of time and space. Based on Sentinel-2 satellite images, regression analysis was carried out to determine the dependency of vegetation indices on soil electronegativity and maize biomass from 73 sampling points in the representative area. As a result, in the study of the growth and development of maize, it was found that the dependence of the Normalized Difference Vegetation Index (NDVI) on maize biomass within 18 vegetation indices was "high" (R2 = 0.76) in spring. The dynamics of maize biomass grown on soils of different salinity levels were developed. NDVI dynamics, which covers the entire growth phases of corn, showed that compared to corn grown in unsalted soils, it slows down the growth of corn in slightly saline soils-up to 11 days, in moderately saline soils -35 days, and in heavily (highly) saline soils -45 days. Characterization of soil salinity and other factors having a positive and negative influence on the growth and development of maize yield in the studied object is also given.

Mapping of Cornfield Soil Salinity in Arid and Semi-Arid Regions

“…The spectral channels of the Sentinel-2 satellite, taken on July 28, were used to calculate this index. In previous studies [Laiskhanov et al, 2022], it was found that the greenest period of corn grown on non-saline soils corresponds to July 28, and it is much later on saline soils. Salinity slows down the growth and development of corn during the growing season.…”

“…With the rapidly population density growth has increased anthropogenic impact, and a combination of climatic features leads to increased salinity and pollution of irrigated soils in this region, resulting soil salinization has become the main restraint for a Mapping of Cornfield Soil Salinity in Arid and Semi-Arid Regions crop production and regional ecosystems [Suska-Malawska et al, 2022]. The Shaulder irrigated massif in the middle reaches of the Syr Darya river, where irrigated lands are most widely used for cornfields, the degree of soil salinity is different and it has been determined that they increase with depth [Laiskhanov et al, 2022]. In determining of the soil salinity in the cornfields, first carried out the division of cornfields, for this, vegetation phenological dynamics were characterized using a time series of vegetation indices derived obtained from satellite data, mainly the Normalized Difference Vegetation Index (NDVI), as a result, the difference in the growth phase of corn and other crops was determined [Jin and Xu, 2013;Segarra et al, 2020].…”

“…In determining of the soil salinity in the cornfields, first carried out the division of cornfields, for this, vegetation phenological dynamics were characterized using a time series of vegetation indices derived obtained from satellite data, mainly the Normalized Difference Vegetation Index (NDVI), as a result, the difference in the growth phase of corn and other crops was determined [Jin and Xu, 2013;Segarra et al, 2020]. The soil reclamation hypothesis manifested a close relationship between the concentration level of salts amassed within the soil and the condition of the current crop [Laiskhanov et al, 2022]. Based on local research, although there is information about the development and main sources of irrigation soil salinity, there is lacking a quantifying the magnitude and mapping its spatial distributions.…”

“…However, knowledge of characterizing and monitoring soil primary and secondary salinity, as well as the correlation between of the soil quality and index values of satellite imagery involves the collection of soil samples for chemical analyses and electrical conductivity (EC) under field work [Laiskhanov et al, 2021]. Most researchers in recent years have been actively using Sentinel 2A and 2B satellite data for such studies, which can provide higher resolution up to 10 m [Segarra et al, 2020;Taghadosi et al, 2019;Laiskhanov et al, 2022].…”

Study of the Ecological and Reclamation Condition of Abandoned Lands and their Development for Sustainable Development Goals

“…Compared with other agricultural areas of the south, Otyrar is well provided with water resources. However, due to inefficient use and the management of water resources, groundwater rises and contributes to soil salinization [45], this threatens the overall sustainability of the crop farming system on irrigated and dry land [20]. The fields in the study area are irrigated once in early spring using flood irrigation, and in summer, it is watered 2-3 times before the end of the vegetation period using the furrow irrigation method.…”