The Role of Mineral Fertilizers for the Optimization of Agrolandscapes in the Volga Steppe Region

Abstract

The Volga region occupies more than 1.04 Million km2 of the Russian Federation. On its steppes (44% of the total area) there is concentrated crop production. Fertilizers play an important role in increasing the yield of agricultural plants. This chapter presents the findings which emerge from studying the effect of mineral fertilizers in a long-term field experiment on agricultural landscapes of the Volga steppes. Information is provided about the productivity of crop rotation and individual crops cultivated in this area: winter wheat, spring wheat, millet, barley, oats. The size of the yield increase caused by fertilizers and their variation due to the moisture conditions during the vegetative period is shown as the nutrient balance and payback indicators for 1 kg of fertilizer grain yield. It is proved that in modern farming conditions with insufficient moisture, nitrogen plays the leading role among fertilizers. Long-term observations revealed the influence of climatic conditions on crop yields and their responsiveness to mineral fertilizers in the agricultural landscapes of the Volga steppes. The chapter also considers the long-term effect of using various doses of mineral fertilizers on the agrochemical properties of southern chernozem: the content of organic matter, gross reserves of nitrogen and phosphorus, as well as their individual fractions. It was revealed that mineral fertilizers significantly affect the mineralization of organic matter and the accumulation of nitrogen and phosphorus compounds which are inaccessible to plants.KeywordsVolga regionSteppeAgrolandscapeMineral fertilizersField experimentGrain yieldSoil fertility