The system of soil protection and general balance of main nutrient elements in perennial plantations of semi-desert natural soil zone of Armenia
Scientific Centre of Agriculture, Isi-le-Mulino 1, AM1101 Ejmiatsin, Armavir region, Armenia
The aim of the research is to study the biological removal of the main nutrient elements from the most common technical grape varieties, as well as from apricot and peach plantations in the farms, situated on semi-desert natural soils of Armenia, to identify the extent of their input and losses due to natural factors and to calculate the balance associated with the soil conservation system in the absence of comprehensive fertilization. In the inter-row spaces of all fruit plantations and even vineyards of the republic, grass cover of productive significance has been established (4.5–6.5 t ha-1 yield of air-dry grass), through which the removal of nutrient elements is 2–3 times higher than the biological removal through trees and vines. The research was conducted in 2015–2020, in the grape, apricot and peach plantations of the semi-desert natural zone of Armenia (Armavir region), where the irrigation norm is 5,000 m3 ha-1, and the atmospheric precipitation is 256 mm, through which 40 kg ha-1 N, 2 kg ha-1 P2O5, and 44 kg ha‑1 K2O enter the soil. The losses due to erosion and washing away are N – 12 kg ha-1, P2O5 – 7 kg ha‑1, K2O – 75 kg ha-1. The balance of nutrient elements in all plantations is negative, nitrogen in plantations with industrial grass cover is 154, P2O5 – 52, K2O – 311, and in the system of black fallow – 15, 16 and 85 kg ha-1, respectively. The negative balance of nitrogen in apricot and peach plantations is 121, P2O5 – 44,K2O – 296 kg ha-1.