| The naturally occurring Quercus mogolica forest is widely distributed in the mountain area of Eastern Liaoning and is extremely important in providing excellent material for use and maintaining regional ecological security.Q.mogolica is not only good material,but also has a high starch content of fruits（acorns）and is an important industrial raw material with high economic value.This paper addresses a problem of unjustified forest structure,not high oak production and utilization,and low comprehensive economic value exerting in the current breeding of native Q.mogolica,investigating and analyzing a native Q.mogolica forest typical of the mount region of Liaodong 25 typical sample structure for native Q.mogolica under different local conditions,combined with the existing data on 3 fixed land standard for Q.mogolica Seed setting impact factors and delineation of suitable habitat conditions in the hope of providing the basis and guidance for establishing highly efficient cultivation techniques such as structure control and taxonomic operation of Q.mogolica stands.The main findings were:1)There is an absolute advantage of Q.mogolica in mature forests of native Q.mogolica,affecting renewal and survival of other tree species.The average thoracic high cross-sectional area occupied by Q.mogolica in canopy layer,sub forest layer were 83.6±12.0%,29.8±19.3%,respectively,and less distributed in renewal layer;Q.mogolica was randomly distributed in stands,and the mean angular scale of wood sampled for Q.mogolica was 0.505±0.012;Q.mogolica exhibited a superior potential state in stands with an average size ratio of 0.219±0.025;Non Q.mogolica species in stands were more admixed,with an average of0.670±0.007.The competitive effective radius of Q.mogolica in stands was around 8 m,and the competitive index decreased with increasing DBH,both of which were power functions;The chest diameter of 11 cm and 21 cm were the threshold points for competitive intensity change;The competitive pressure experienced by Q.mogolica was mainly from within species,while the competitive pressure for the other tree species was mainly from Q.mogolica.The competitive index leveled off when the DBH grew to 20 cm.Therefore,for Q.mogolica forests with the goal of cultivating large diameter wood,the target tree retention density was set at 200 trees·hm-2,2)Different site conditions and stand conditions affected oak forest oak yield significantly.The yield influencing factors for oak in Mongolia were ranked according to size as follows:chest diameter>elevation>slope>density>slope>canopy>tree height>soil thickness>slope>depression.The maximum single grain fruit weight of oak was strongly correlated with seed setting per plot area(r=0.614;Oak yield showed a decreasing trend with increasing forest age;With increasing density,the oak yield first increased and then decreased,and reached a higher yield(1216.9 kg·hm-2)at an appropriate density(766-800 trees·hm-2).3)There was a significant difference in the amount of forest tree growth in mature forest trees of native Q.mogolica under different native conditions.The ranking of factors influencing the magnitude of growth volume was:slope>slope>slope>soil thickness;The most suitable set-up conditions for Mongolian Quercus forest growth in the Liaodong mountain region are a mid slope,a slope from 16°to 25°,a Yang slope and a lot with a thicker soil layer;According to these,the type of Quercus mongolicus linli in the Liaodong mountain can be divided into 3 site type groups,16 site types.The results of the present study indicate that for the current Q.mogolica secondary forest,below 11 cm chest diameter,rearing interval is necessary to reduce its intensity of competition;When the chest diameter reaches more than 21 cm,no density control measures are necessary.Q.mogolica forest on a slope,half Yang slope,and mid slope site was suitable for the development of a dual use fruit forest with a density ranging from 766 to 800 trees·hm-2;Whereas in a habitat with a thicker soil layer,a wood forest for broad-leaved admixture of Q.mogolica can be developed,it is advisable for Q.mogolica to retain 200 trees·hm-2. |
