The Research Of Larix Principis-rupprechtii Forest Edge Characteristics

This paper compares the light intensity of forest edge, species richness index, soilphysical and chemical properties, the change rules of microorganism quantity and soilenzyme activity of six different density Larix pricipis-rupprechtii plantations in JibeiMountain, aslo analyzes the characteristics of the soil of Larix pricipis-rupprechtiiplantations from different distance of the forest edge, and in dentifies the mainenvironmental factors for planting density rang which can most reflect the forest edgeeffect. And this can provide a reference for reasonable operating the Larixpricipis-rupprechtii plantations in Jibei Mountain.(1) The density of630per/hm2Larix principis-rupprechtii edge herbal Menhinickrichness and relative light intensity increases with distance from the forest edge horizontaldistribution, there is no obvious relationship between the size of the forest edge distance.The remaining density first decrcreased and then tended to be stable. With the increasing ofdistance to the edge, soil bulk density was deeases.(2) Soil pH value, organic matter, total nutrient and available nutrient content wereextremely significant difference at forest edge in different density stands, the nutrientcontent of different distances to the edge were not significantly. This showed that soilnutrient content did not show obvious effect edge with the increase of forest edge distance.(3) Under6kinds of density edge of the Laryix principis-rupprechtii plantation soilmicroorganisms (bacteria, fungi, actinomycetes and the total number of micro-organisms)with significant differences; whereas the same density edge of the Larixprincipis-rupprechtii stands in microbial bacteria have an absolute advantage, threemicroorganisms order of magnitude the number of bacteria> actinomycetes> fungi. Fromthe edge of the Larix principis-rupprechtii plantation at0m to30m at the soilactinomycetes and bacteria were shown a significant increase.(4) In different densities at the edge of the Larix principis-rupprechtii stands soilenzyme activities (soil inverts, unease, acid phosphates, catalane) were significantlydifferent; inverts activity and in addition, other microbial effect and from the stand edge ofthe existence of significant differences in the different distances. (5)6kinds of different densities of the Larix principis-rupprechtii size edge effectscomposite score of1500per/hm2(8.190)>1850per/hm2(4.238)>1180per/hm2(3.612)>2150per/hm2(-5.336)>920per/hm2(-6.875)>630per/hm2(-13.498). High-density edgeeffect larch plantation of larix principis-rupprechtii is the more obvious.