Agrocenosis Stability during Long-Term Application of Fertilizers on Soddy-Podzolic Soil

Eurasian Soil Science - In a long-term field experiment in the western part of the nonchernozemic zone of Russia (Smolensk oblast) on sandy loamy soddy-podzolic soil (Albic Glossic Retisol...     

Agroecological Efficiency of Organic and Mineral Fertilizers under Frozen Soil Conditions

Investigations were carried out on permafrost taiga soil in Central Yakutia in a field factorial experiment with a wide range of rates and combinations of cattle manure and mineral fertilizers. The advantage of an organo-mineral fertilizer system in N₆₀P₆₀K₆₀ rates was shown against a background of 40 t of manure per hectare, which provides, under watering conditions, potato tuber yields of 18 t per hectare with starch content of 13.9%, which is 47.8% higher than in the control without fertilizer use. The yield of potatoes under the organic system with annual manure rate of 40 t per hectare was at the same level with the mineral system, but tubers contained more starch, 12.8%. It has also been established that organo-mineral and organic systems have a positive effect on the agrochemical properties of the soil, optimize its humus state and phosphate and potassium regimes. For the mineral fertilizer systems in rates of N₆₀P₆₀K₆₀, the yield increment was significant, but it did not exceed 17.8% with a lower starch content in tubers, 11.5%, and a negative balance of humus, phosphorus, and potassium in the soil.     

Dynamics of the mobile forms of phosphorus and potassium in the soils of prolonged trials

During prolonged field experiments performed with various types of loamy soils, the application of phosphorus and potassium fertilizers increases the content of mobile forms of phosphorus and potassium mainly at the first rotations of field crop rotations only. Later, under positive balance, the content of mobile forms of these elements in soil does not increase and even tends to decrease due to the more intensive transformation. In the case of the negative balance of phosphorus and potassium, plants are supplied with nutrition by immobilization of fixed forms of these elements. In the sandy loam soils, these processes are less pronounced due to the lower absorption capacity of the soils to phosphorus and potassium.     

Growing potatoes above the arctic circle

The possibility of growing potatoes with a yield of 60 cwt/ha by using organomineral and organic fertilization systems has been established on the basis of the results of a field experiment in the Verkhoyansk region of Yakutiya on taiga cryogenic soil.