Analysis Of Effects Of Intermediate Felling On Artificially Induced Broad-leaved Korean Pine Forest And Studies On Seedlings Of Pinus Koraiensis With Different Shading Treatments

Base on the fore studies, in view of the existent problems in the course of inducingnatural secondary broad-leaved forest to artificial broad-leaved Korean pine forest in theeastern mountainous area of Liaoning province, the systemic studies were made on the effectsof stands of different intermediate felling intensities with Pinus koraiensis of artificialregeneration understory and the growth of seedlings of Pinus koraiensis with different shadingtreatments. The main conclusions of investigation were summarized as follows:1.The effects of intermediate fellingIntermediate felling hardly affected height but promoted diameter obviously of thebroad-leaved trees reserved, the diameter and volume of individual increased with theintensifying of intermediate felling. The intermediate felling on superstratum improved lightenvironment understory, and promoted the diameter and height of Pinus koraiensis, thegrowth rate increased with the intensity.Intermediate felling promoted the increase rate of broad-leaved stand volume andincreased with the intensity. The volume of middle intermediate felling intensity and slightlyintermediate felling intensity went beyond the CK obviously, and more advanced for themid-intensity in 14 years after intermediate felling. The volume of strongly intermediatefelling intensity was the least because of the fewer leaved-broad trees. The volume increaserate was low and stable in the stand without artificial thinning. Intermediate felling decreasedthe rate of natural thinning, thus reduced the loss of volume.Middle intermediate felling intensity area had the most fallen reserves and the strongestability of keeping water, slightly intermediate felling intensity area took the second place.Intermediate felling promote the soil physical property, from the better to the worse, thesequence was middle intensity, slightly intensity, strongest intensity, CK, entirely cutting.The variety rule of nutrient content in soil was not obvious with the intermediate fellingintensity, but the entirely cutting area has the least.The suitable resource level (light resource mainly) was benefit for the increase of thevegetation's diversity index under canopy in stand of middle intermediate felling intensityarea.2. The effects of shadingRelatively, the LCP of Pinus koraiensis seedling was low, and the LSP was high. Itshowed the biology characteristic that seedling of Pinus koraiensis was able to bear shadingand fond of light. With the enhance of shading treatment, its LCP decreased andφincreased. On conditions of test, the LSP and the Pmax of Pinus koraiensis seedling in treatment of74.2% transmissivity was the highest, but the Rd of it was relatively high too.The diurnal change of Pn curve of Pinus koraiensis seedling has both apexes in full lightand one apex in shading environments. In the different shading treatments, the main restrictfactors on Pn, E, COND, Pn/Ci were different.With the enhance of shading treatment, the LUE of Pinus koraiensis seedling increased,and the sequence of WUE and CUE from higher to lower was 74.2%,CK,38.7%,9.7%.With the enhance of shading treatment, the content of Chla, Chlb and Chl(a+b) of Pinuskoraiensis seedling all increased obviously, especially the proportion of Chlb content.Strong light promoted ramification and diameter growth of Pinus koraiensis seedling,and decreased the angle of ramification, but the seedling height and the length of branch weremost in 74.2% transmissivity treatment. The biomass of seedling from more to less was74.2%, CK, 38.7%, 9.7%. The proportion of leaves biomass increased in shading environment,but the more biomass of roots was accumulated with the increase of light.