Study On Typical Mixed Needle-leaf Forest Structured Management Technology Of Mountain Xiaolongshan Forest Area

Structured forest management technology is one kind of forest management methodwhich is based on stand spatial structure optimization. It had been applied widely in theresearch and practice of natural forest management, and it also had been paid close attentionby forest managers and researchers. In this thesis, forest structured management theory andtechnology were applied in second subcompartment of secondary oak coniferous andbroadleaf mixed forest which located in Daganzi watershed of west Qinling mountain inBaihua forest farm, Xiaolong mountain Forest Bureau, Gansu Province. Systematic researchwas implemented by the location investigation of whole subcompartment trees, whichincluded the aspects of survey method, stand structure analysis, forest operation design andmanagement effect evaluation. Thus, the main conclusions were obtained as follow:(1) By the location investigation of whole subcompartment trees, we obtained that thearea of the second subcompartment, average DBH (Diametre at breast height), average height,total individuals and total volumes were0.9067hm2,12.0cm,11.1m,1942trees and104.85m3,respectively. Comparing with the whole subcompartment individual investigation, thestatistical results of survey methods included50m×50m—large plot investigation,30m×30m—standard plot investigation and structural unit point sample investigationconsisted of49referenced trees and adjacent trees were approximately equal. The analysisresults using forest structured founding.on sampling theory, with reference to the tree and4strains of adjacent wood five trees constitute the structure of the unit, not to repeat as theprinciple to set up a sampling point, not only can meet survey precision, also reduced thesurvey field intensity, improve work efficiency, at the same time point sampling methodintroduces the survey of the spatial structure parameters, including the Angle scale, size score,mixed degree, a better analysis of the existing spatial structure of forest stand, to determinethe direction of and optimize the structure of space provides a good data to support.(2) The stand type is pine-oak mixed forest in second subcompartment in Daganzi valley.The broad-leaved trees were consisted of sharp tooth oak hardwood dominated in the forest,sumac, lobular camphor, iron wood, linden, birch, maple, elm44species. The coniferousforest mainly covered by pinus tabulaeformis. pinus tabulaeformis are mostly artificialplanting, there is a small amount of natural pinus tabulaeformis and China distribution,floristic composition3oil3sharp and hard, width1China is a typical mixed needle, forestage50years. Forest is given priority to with trail order in the trees, a negative exponentfunction, diameter distribution fitting equation of y=5171e-0.228x(R2=0.960), the mean tree diameter distribution of q is1.364; The average score of0.499size of forest, pinustabulaeformis dominance index was0.445, sharp tooth oak is0.409, the second China is0.305, the advantage of the other trees are below0.20degree; Stand is0.554, the averageAngle of scale in (0.517，1], and between the group that distribution pattern for distribution;the average mingling degree of forest stand is0.667, belonging to the moderate to strengththeir mixed transitional state: Shannon Wiener diversity index of2.(3) Small Lin2layers of1.7layer, vertical structure did not achieve the standard stand;Forests update medium, more than30cm baby fewer; Naturalness of SN value of0.616, rank5, belongs to secondary forest. Business urgency evaluation index is0.56, is very urgent,direction of management is: adjust the Angle of the stand scale, improve the degree ofdominance of climax tree species; Improve the level of maturity and health of trees, at thesame time, need to consider increase the survival rate of seedlings, the quantity and quality.Cultivating goal is stratified to pine oak mixed forest. Logging is given priority to withparenting, design strength of the cutting number552strains was28.4%, the accumulation of19.905m3, intensity control under19%.(4) From the space utilization degree, species diversity, species composition, diameterdistribution, species competition of this a few aspects to evaluate the operation effect of theforest, and to stand before and after the operation of various indexes were compared. Afteroperation stand a small forest canopy density decreased from1.0to0.8; Average angulardimension is0.501, is smaller than before operation, fall in [0.475,0.517] between, belong tothe reasonable state; Tree species composition changes after operation, other hardwood ratioreduce, reduce the three kinds of plants, a slight change of diversity index, but not much value;Average diameter distribution q decrease1.297, belong to the scope of reasonable distributionof different diameter Lin; Operation after the climax tree species China, pinus tabulaeformisdominance respectively from the management before0.3, and0.440.33and0.45, after theoperation,climax tree species and the degree of the advantage of main associated tree speciesare improved and adjusted to a certain extent of tree species. The management has reached thedesign target, by raising five homework.In short, in the western qinling xiaolongshan forest forest structured management theoryand methods, especially with reference to the tree and4strains of adjacent wood five treesstructure unit consisting of survey results, to better evaluate the existing forest stand structurecharacteristics, evaluation of natural state, identifying business urgency and determine thedirection of management, in xiaolongshan forest region is a large needle mixed operationpromotion prospects.