Restoration of Degraded Lands in the Arid Zone of the European Part of Russia by the Method of Phytomelioration

Abstract

In arid areas, it is necessary to apply phytomelioration widely to create an organized, stable and ecologically well-maintained forest–agrarian landscape in which agricultural lands can provide diverse and stable products, and to provide optimum ecologyfor the existence of a natural and anthropogenic system. The aim of this work is to select shrub and herbaceous plant species for the restoration of degraded lands in the arid zone of the European part of Russia with the prospect of preserving and increasing the productivity of native biodiversity, and the structure and dynamics of pasture ecosystems. The object of this study is the desert and semi-desert zone in the south-east of the European part of Russia within the Caspian lowland. The productivity of vegetation in the studied zone is largely determined by soil conditions, seasonal weather phenomena and animal grazing. The lowest forage productivity is characterized by the winter period with very strongly beaten white-field-grain pastures on unsalted, weakly- and medium-salted light chestnut soils; very strongly beaten bulbous-bluegrass-white-field pastures on saline deep, medium and strongly saline light chestnut soils; or medium-beaten black-wormwood and bulbous-bluegrass-black-wormwood pastures on small and crusty salt flats. The highest productivity is observed in the spring-summer period on unbroken areas of unsalted, weakly and medium saline light chestnut soils occupied by white-field cereal phytocenoses. The intensity of transpiration of perennial forage grasses growing on sandy loam soils of the dry steppe zone was measured. The analysis of biomorphological features of native forage species resistant to climate change and pasture load, and promising for phytomeliorative reconstruction of degraded pastures include: ecotypes of the genus Artemisia (A. pauciflora, A. Lercheana) and the genus Agropyron (A. cristatum, A. fragile, A. pectinatum), growing on various soils in natural conditions in the south-east of the European part of Russia. It was revealed that the seed productivity of Agropyron varieties varies within 0.5–4.0 c/ha depending on the variety, the method of sowing and climatic conditions of the year. To increase seed productivity, wide-row sowing with row spacing widths of 45 and 70 cm is promising.