Effects of alfalfa and oatgrass on soil nutrients in newly cultivated land on the Loess Plateau, China

Some newly cultivated land formed by "ditch and make land" on the Loess Plateau has poor soil nutrient, low fertility and unsustainable development. Medicago falcata L. and Arena sativa L. were selected as experimental subjects to investigate the effects of different greening plants on the nutrients of newly cultivated land, providing a theoretical reference for the improvement of soil nutrients in newly cultivated lands on the Loess Plateau. The results showed that in the initial stage of planting grasses on newly cultivated land, within the 0-60 cm soil layer, the soil organic matter, total nitrogen, total phosphorus and alkali-hydrolyzed nitrogen contents of alfalfa and oatgrass increased with the increase of soil depth; the soil total potassium, available potassium and available phosphorus of alfalfa and oatgrass did not change clearly with the increase of soil depth. The soil nutrient indexes of alfalfa and oatgrass were analyzed by principal component analysis, in the short-term comprehensive effect of grasses on soil nutrient improvement was alfalfa > oatgrass. Planting alfalfa can improve the soil nutrient status in newly cultivated land in a short time.