Investigation and Assessment of Soil Fertility in Agroforest Landscapes
The article presents the research materials of agrochemical properties of soil land use in the agricultural production co-operative ”Kolos”, Oktyabrsky district of the Volgograd region. The studied agroforestry landscape is located on the left bank of the Tsimlyansk reservoir, in the watershed of the Myshkov River. The territory of the farm is typical for the light chestnut sub -- zone of soils in the South of the Volgograd region. The results of the research are data on agrochemical properties of soils, their analysis and relative assessment, as well as proposals for improving fertility. The analysis of soil samples was carried out in accordance with the guidelines for the comprehensive monitoring of soil fertility of agricultural land. The soil sample was taken from an area of 40 hectares and is a mixed sample composed of 20 individual samples taken from the depth of the arable layer (0 -- 0.30 m). The total area of the surveyed arable land is 13.3 thousand hectares. Under laboratory conditions, chemical analyses were carried out and such parameters of soil fertility as humus content, content of macronutrients (NPK), content of water-bearing salts, soil granulometric composition, pH index were determined. Laboratory data are summarized in the table. The analysis of experimental data revealed the ranges of the studied parameters and identified four groups of relative soil fertility: fields with high, medium, low and very low fertility. The grouping of fields based on the account of soil fertility will allow using more differentiated and effective application of the system of measures aimed at increasing the yield and preserving soil fertility.
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