Lucerne Proportion Regulates Competitive Uptake for Nitrogen and Phosphorus in Lucerne and Grass Mixtures on the Loess Plateau of China

Mixtures of legume and grass are used worldwide to gain advantages in forage production ecological maintenance. However, competition for nutrients by legumes mixtures has not been fully explored. The aim was determine how the proportion affected nutrient mixtures. Treatments included two species combinations five sowing ratios. Competitive ratios (CR) lucerne nitrogen (N) phosphorus (P) over grasses were assessed analyze competition. Total N P uptake mostly lower under timothy-containing (MPs) than smooth bromegrass-containing (MBs). Proportions both (NM%) (PM%) higher MPs MBs. Higher total found half-lucerne (M5P5 or M5B5) other grasslands. NM% PM% tended be mixtures, although they showed little difference among Lucerne CR greater MBs, when There soil density grasslands same cut, whereas variable. Competitiveness depends largely on initial ratio. High significantly reduce density, leading limitation reduced uptake. On Loess Plateau China, mixing with bromegrass is recommended increase harvest P, specifically at ratio 5:5.