Do heterogeneous nutrient patch scale and distribution order in the habitats always influence on the biophysical characteristics of Zoysia japonica?

摘要

Previous studies have shown that small scale resource heterogeneity may strongly influence plant fitness and many ecological processes. Clonal plant species performed better under various heterogeneous environments compared with homogeneous ones. However, the patch scale and the distribution order in the habitats may affect the clonal growth and has remained unclearly elucidated. We used typical stoloniferous clonal plant Zoysia japonica as study material, through analyzing the performance of its clones in the heterogeneous environments with different patch sizes (where amount of nutrient supply was same to all heterogeneous treatments with different patch levels). Levels of patch soil nutrients and patch distribution orders in the habitats, comparing with the homogeneous ones, aiming to test the hypothesis that patch scale and distribution order in the habitats always affect the performance of clonal growth of Z. japonica . We did not find significant differences ( p ≥0.05) in the total biomass of clonal growth of the species under different heterogeneous conditions, whereas we found significant difference between heterogeneous and homogeneous treatments,total biomass of clonal growth under heterogonous conditions compared with the homogenous nutrient-rich treatment C1 and homogenous nutrient-zero treatment C2 ( p ≤0.05), respectively. The results demonstrated that due to mutual translocation of resources among connected ramets in all heterogeneous treatments increasing heterogeneous patch scale and distribution order in the habitats did not always affect the performance of clonal growth of Z. japonica but the interactive effect of nutrient distribution and patch scale significantly affect the growth of Z. japonica .