The Stand Spatial Structure Of Pinus Sylvestris Var. Mongolica And Its Regeneration Succession Rules In HongHuaerji

Pinus sylvestris var. mongolica which natural distribute in Inner Mongolia Autonomous Region Honghuaerji is the most representative natural Pinus sylvestris var. mongolica forest in china.The fist Pinus sylvestris var. mongolica plantation is introduced from Honghuaerji,thus study of natural Pinus sylvestris var. mongolica forest in Honghuaerji is importance to construction and management of natural and Artificial forests.This paper,based on four samples polts in Inner Mongolia Autonomous Region Honghuaerji,analysed spatial structure of stand by method of mingling,neighborhood comparison and point pattern analysis;analysed regenration of Pinus sylvestris var. mongolica saplings in different forest stand by Hamill & Wright statistic and analysed the intraspecific and interspecific competitions by Hegyi's competition index model.The preliminary results were got as following:(1) Pinus sylvestris var. mongolica was the exclusive dominant population in community,bing in some kind of intermediate or above status meanwhile.Broadleaf trees was suppressed,being inferior. Community structure of mixed stand was more complex and steady than pure Pinus sylvestris var. mongolica forest. (2) Because of intensive intraspecific competition,distribution pattern of Pinus sylvestris var. mongolica adults presented random with the increasing of scale in different forest stand. (3 ) Spatial association between Pinus sylvestris var. mongolica adults and conspecific saplings would be weakened greatly on large scale. Relationgships between Pinus sylvestris var. mongolica adults and broadleaf trees presented positive association,and it were the most significant on scale 4m to 5m.Therefore Pinus sylvestris var. mongolica saplings usually distributed with 4m round broadleaved trees. (4) Pinus sylvestris var. mongolica saplings in coniferous broad-leaved mixed forest grown better than pure Pinus sylvestris var. mongolica forest. Additionally,Pinus sylvestris var. mongolica saplings around broadleaved trees grown better than saplings around Pinus sylvestris var. mongolica adults. (5 ) In coniferous broad-leaved mixed forest intraspecific competition was more intensive than interspcific competition.In pure Pinus sylvestris var. mongolica forest competition stress generated by Pinus sylvestris var. mongolica has severe influence on other population and community succession.This reasearch is crucial to optimize forest spatial structure,promote regeneration,adjust competition relationship of trees,and it will provide scientific basics for utilizing economic benefits and ecological beneits of natural Pinus sylvestris var. mongolica forest.