Change in the soils’ fertility level of tea agrocenoses in the transition to cultivation without mineral fertilizers in the humid-subtropical zone of Russia

Research was carried out on the basis of preserved field multifactor experiment tea crop ( Camellia sinensis (L.) Kuntze) in conditions Sochi Black Sea coast. The application NPK fertilizers different doses and combinations according to experimental scheme annually from 1986 2011. Since 2012, use has been completely discontinued. fertility indicators long-fertilized brown forest acidic soils (in layers 0-20/20-40 cm) were compared with those after 7-8 years fertilizer withdrawal. During period fertilizers’ application, level soils’ nitrogen supply significantly exceeded control (by 30-75/30-56 mg/kg depending fertilizers). After discontinuity, equalization occurred all options. content labile phosphorus previously fertilized high (120 kg P 2 O 5 ha -1 year more), during experiment’s conservation decreased by 450-500/350-450 mg/kg, but 2-2.5 times; low doses, have not changed significantly. In highly supplied potassium, element 70-140 mg/kg. yield 2019-2020 equally (12-26 cwt/ha) options, 2.2-3 times lower than plantations. withdrawal, there a decrease acidity (an average increase pH 0.18-0.24/0.12-0.20 units) agrogenic-acidized an their oppressed respiratory activity (on 1.6 times). These changes reflect tendency soil self-restoration removal load.