REGULARITIES OF THE IMPACT OF FOREST STRIP CONSTRUCTIONS AND FERTILIZERS ON THE MICROCLIMATE AND YIELD OF SPRING WHEAT IN THE SOUTHERN CHERNOZEM
The purpose of the research is to establish patterns of increasing the yield of spring soft wheat «Favorit» sown with the use of mineral fertilizers in fields with a system of protective forest strips (PZLP) of various designs. 13 PZLPS with an area of 45 hectares were created in the period from 1968 to 1970 on the lands of RosNIISK Rossorgo. PZLPS are located perpendicular to the harmful south-easterly winds. The inter- lane distance is 400-420 m. The stripes are made of pedunculate oak (Quercus robur) and hanging birch (Betula pendula). The forest cover of arable land is 4.5%. The PZLP system is complete. The indicator of protection of adjacent lands is more than 80%. The increase in crop yield in the crop rotation system occurs under the influence of a design that forms the microclimate of adjacent fields. The effect of microclimatic indicators on the dynamics of wheat yield depends on the moisture content of the growing season. In the average (hydrothermal coefficient - GTK = 0.65) and medium-wet (GTK=0.88) years, the yield of wheat sown under the protection of forest strips is most influenced by: air humidity, water deficit and air temperature. In very humid (GTK=1.81) and humid (GTK=1.15) years, the effects of microclimatic indicators on crop yield were arranged in descending order of importance: air temperature and humidity, water balance deficit. In the average dry (GTK = 0.45) and dry (GTK= 0.30) years, wheat yield is affected by water balance deficit and air humidity. The impact of the PZLP design and fertilizers on wheat yield also depends on the year of moisture cultivation of the crop: in the middle - with a slight advantage of fertilizers (up to 7.3%), in wet, the effect of fertilizers increases to 67.7%, in dry - the prevailing value in the formation of the crop crop is acquired by the PZLP design - up to 18.8%. On average, over the five years of research (2015-2019), fertilizers had a predominant effect on wheat yield compared to the design of PPLP up to 9.0%.