What is a Safe Site?: Neighbor, Litter, Germination Date, and Patch Effects

摘要: To investigate some of the factors that determine fate a seedling, censuses seedlings two native grasses, Aristida longiseta and Bouteloua rigidiseta, were made at frequent intervals in Texas grassland for 2 yr. Seedlings both species with neighboring or juvenile plants either within cm had higher rates survival growth than those without such neighbors, implying effects aggregation favorable microsites outweighed competition among these plants. Neighboring adults species, juveniles other positive instances, negative others. Litter, even amounts too small to cover surface, reduced while surface rocks may have increased them. Overall, germinated earlier autumn more successful. The rank order quadrat favorableness varied complex fashion between years, census intervals, germination cohorts. This variation patch must prevent populations from reaching stable spatial distribution age any given patch.