Nutritional Regime of the Soil and Growth Activity of the Apple Tree Root System in Orchards with Legume-Cereal Grass IntercroppingAleksandr Gurin, Svetlana Rezvyakova and Nikolay RevinE3S Web Conf., 247 (2021) 01029DOI: https://doi.org/10.1051/e3sconf/202124701029