Fire and Temperature Effects on Seed Germination from Burned Plots and Unburned Plots in Sheepgrass Steppe Effects of tourism and recreation on seeds germination rate two herbaceous plants in Langya Mountain scenic area THE TEM PERATURE EFFECT OF LOW-ENERGY ION BEAM IMPLANTATION ON SEED EXPERIMENTAL STUDY ON SEED STORAGE OF POPULUS SIMONII MORPHOLOGICAL AND STRUCTURAL VARIATION OF SEEDS FROM TETRAPLOID Robinia pseudoacacia