Productivity of slope pastures under the influence of protective forest plantations and mulching in the forest-steppe and steppe of the Volga upland

Establishing the regularities of increasing soil fertility and grass productivity of slope pastures under the influence of protective forest plantations and mulching was the purpose of the study. The experiments were carried out according to the methods of profile research institutes and sci- entists of Russia. Materials of observations were processed by methods of variation statistics with the use of professional versions of standard computer programs. The main indicator of agroland- scape type in slope pastures is the slope slope value, which determines the degree of soil fertility and productivity of slope pastures. The content of humus in soil horizon A decreases from 4.69 to 1.97 % in southern chernozem and from 2.20 to 1.86 % in gray forest soil when the slope value in- creases. Nitrogen, phosphorus and potassium content decreases in all soil types by 1.5–4.0 times, and nitrogen content is rather low – less than 15 mg/kg. The protective forest plantations placed on sloping pastures and the application of mulching of the soil surface in the inter-band spaces, depending on the slope of the sloping pasture, increased the humus content in soils by 0.16– 0.41 % in absolute value, NPK – by 9.1–30.0 %: a greater increase corresponds to the erosion hazardous types of agricultural landscape (slope steepness over 30). Productivity of pastures de- pends on soil fertility level, autumn and winter precipitation, moistening of vegetation period of plants growing. Grassland productivity naturally decreases with increasing slope of southern chernozem soil up to 66.7 %, gray forest soil – up to 92.1 %. Protective plantations and horizontal mulching with straw cuttings and fallen leaves allow increasing grass productivity up to 26.6 % on southern chernozem and up to 28.6 % on gray forest soil. The productivity of pasture grasses is 88–95 % related to the slope slope, the content of humus and nutrients in the soil, and the degree to which the pasture is protected from erosion.