Pisum sativum as a cover crop for biological land reclamation behind the polar circle

The purpose of the researches was checking up the possibility of cultivation of Pisum sativum in the conditions of subarctic tundra of southwest part of the Taimyr Peninsula and the detection of the features of growth and development of plants for further using the crop at biological recultivation of technologically disturbed lands. The researches were conducted in 2016-2019 in the Taimyr (Dolgan-Nenets) municipal area of Krasnoyarsk Region in forest-tundra zone of the Yenisei Far North on technologically disturbed lands. Six varieties of peas were involved in the experiment: Annushka, Kemchug, Svetozar, Radomir, Ruslan, Yakhont. Sowing was carried out after mechanical tillage. All the varieties showed good survival in local conditions. The maximum viability of seeds on average for 4 years was observed in the variety Ruslan with using mineral fertilizers (azofoska) in N60P60K60 in the dose of 87 %. Polar day set in local conditions from May, 19 to July, 25 was one of positive factors for fast adaptation of peas as the cultures of long day developing at average temperatures. Vegetative period in 90 days was enough for this culture to pass through all the phases of phenogenesis to full ripeness. Morphological signs are represented by smaller sizes, than in the southern regions. At the same time the crop created large aerial mass and developed root system; it contributes to the strengthening of soil structures, the decrease in kinetic energy of melt water suppressing the flow velocity. The maximum productivity of peas on average for 4 years was revealed in the variety Radomir in the variant with mineral fertilizers in N60P60K60 dose + backstage willows - 2.35 t/hectare. Perennial herbs used as the main cultures at biological recultivation in the first year of life grow slowly, and large aerial mass with root system are poorly developed, remaining by the end of the vegetative period in tillering phase. The crops of peas in mix with perennial herbs as integumentary culture will allow receiving in the first year of carrying out biological recultivation on restored lands vegetable cover promoting the prevention of developing of water erosion.