Abstract:
Pinus tabulaeformis is one of the important species of plantation on Loess Plateau.In this study,peers planted Pinus tabulaeformis seedlings on four typical growth environments were chosen,analyzed seedling height,correlation between seedling height and base diameter,changes in seedling survival and mortality,and correlation between seedling growth and environmental factors.The results showed that seedling survival rate order is as follows, grassland habitats, bush habitat, weed trees habitat, and birch forest habitats.The seedling mortality peak in the first year after planting and the second year,and the largest number of deaths in the first year which may be related to the conservation measure in the first year.The seedling growth height and base diameter is positively dependant on the following order, grassland habitats,bush habitat,the weed trees habitat,and birch forest habitats. The main environmental factors affecting seedling growth in the region is as follows, soil pH, planting density, light intensity, slope and dominance degrees of other species, the most important factors are soil pH,dominance of other species and planting density, followed by light intensity and slope. The above results indicate that to effectively improve the survival rate of seedlings and promote its healthy growth, pH neutral or near-neutral soil are firstly considered. Taking the lighting conditions into account, addition of planting density should be controlled in the range from 8/10m2 to 10/10m2 ,and other shrubs and weeds should be cleaned also to ensure the required nutritional conditions of seedling growth.Slope of planting ground should be less than 20 degrees planting.Otherwise, it will cause adverse impact to seedling growth.
