Effects of nitrogen limitation on Leymus Chinensis clonal growth form and bud bank

Abstract

Nitrogen is an important element which affects the growth and clonal growth of plant species in grassland. Leymus chinensis (Trin.) Tzvel is a dominant species in grasslands with a high nutritional quality; however, data on the effects of low nitrogen concentration on L. chinensis clonal growth strategy are limited. The aim of this study is to evaluate the response of clonal growth of L. chinensis to low nitrogen concentrations. The growth form and biomass allocation ratios of L. chinensis under different low nitrogen concentrations were evaluated, and the quantitative characteristics of three bud types were analyzed. The proportion of spreading ramets was favored by low nitrogen supply, indicating that L. chinensis under low nitrogen conditions primarily exhibits a guerrilla growth form, meaning a long mean spacer length and production of spreading ramets. Under limited nitrogen conditions, biomass distribution was mainly concentrated in underground organs (including the roots and rhizomes), while the high proportion of axillary rhizome buds suggested that L. chinensis grows primarily by occupying effective living spaces under low nitrogen conditions. The balance between two clonal growth form and the change in the proportion of different types of buds is an important strategy for L. chinensis to cope with nutrient limitations.