Carbon Storage Of Pinus Yunnanensis And Carbon Loses Of Pinus Yunnanensis Caused By Monochamus Alternatus

In view of the research was gap that forest health dynamics changes especiallyimpact of forest carbon sequestration ability after being xylophagous insects attacked.This paper made Pinus yunnansnsis was research object, Pinus yunnansnsis is a uniquespecies in southwest region. By the method of standard trees, we made a systematicresearch on the difference of biomass and carbon storage and net primary productionbetween healthy and pest of Pinus Yunnanensis in the forest of tianzimiaopo Nanhuacounty and the forest of beishan Yuxi county. Food consumption of Monochamusalternatus and population of Monochamus alternatus and lethal plant by Monochamusalternatus were also researched in this paper. Based on the above researches, thechange of Pinus Yunnanensis carbon losses after being attacked by Monochamusalternatus was analyzed. The results showed that:（1） The biomass and carbon storage of different Pinus Yunnanensis status wereincreased with DBH class. The number were7.579～9.389kg per plant and3.875～4.812Ckg per plant of healthy Pinus Yunnanensis biomass and carbon storage in5～7.5cm DBH class that increased57.991～89.875kg per plant and29.684～46.007Ckg perplant in12.6～17.5cm DBH class. The number were6.174～8.495kg per plant and3.154～4.350Ckg per plant of pest Pinus Yunnanensis biomass and carbon storage in5～7.5cm DBH class that increased38.003～79.533kg per plant and19.455～40.713Ckg per plant in12.6～17.5cm DBH class. The difference of biomass and carbonstorage between healthy and pest wood increased with DBH class. It was no significantdifference in5～7.5cm and7.6～12.5cm DBH class. In12.6～17.5cm DBH class, therewas a significant difference. The difference of biomass and carbon storage were19.988kg per plant and10.229Ckg per plant between health and pest wood in Nanhua.Compared to healthy wood, biomass and carbon storage of pest wood respectivelyreduced34.47%and34.46%. The difference of biomass and carbon storage were 10.342kg perplant and5.294Ckg per plant between health and pest wood in Yuxi.Compared to healthy wood, biomass and carbon storage of pest wood both reduced13.00%.（2） There was a certain change that the proportion of Pinus yunnanensis organbiomass in different DBH class. With the increasing of DBH class, the biomass ofstem and root showed first decreased and then increased, branch and needle showedfirst increased decreased and then decreased and bark expressed relatively stable. Theview from space distribution of various organ biomass, stem and bark was the largestin the layer of0～2m, account for28.06%～28.89%and4.08～5.39%of total aerialparts biomass. The branch and needle were largest in the layer of6～8m by naturalpruning effect and branch age, account for32.01%～47.55%and32.58%～44.97%ofeach totalbiomass. Root biomass rapidly reduced with increasing soil depth.Approximately64.92%～65.98of total root biomass of Pinus yunnanensis distributed inthe surface layer of0～30cm, and only34.02%～35.08%in the other layers. The regression model indicated that Pinus Yunnanensis and its organs biomass had a positivecorrelation withtree height （H） and diameter at breast height （D）. The total biomass hada high correlation coefficient in biomass model.（3） Because of the reduction of leaf biomass by Monochamus alternatus attacked,leaf area of healthy wood was larger than pest in the same DBH class. The researchof NPP showed that Except for5～7.5cm DBH class, NPP of pest Wood was lessthan healthy wood in same DBH class. The difference of NPP increased with DBHclass between healthy wood and pest. In the forest of tianzimiaopo, the difference ofNPP between healthy wood and pest was1.183768kg·a^-1in7.6～12.5cm DBH classand it was1.597264kg·a^-1in12.6～17.5cm DBH class. In the forest of beishan, thedifference of NPP between healthy wood and pest was0.760065kg·a^-1in7.6～12.5cmDBH class and it was1.38545kg·a^-1in12.6～17.5cm DBH class. By regressionanalysis, regression equations were established fitting correlations between carbonstorage and NPP. We achieved the object that calculation of biomass by photosynthetic indexes.（4） Experiment show that, average carbon loss was12.912±0.419g that caused byone generation of Monochamus alternatus feeding. Combined with the research thatdifference of NPP between healthy and pest of Pinus yunnanensis and feeding amountof Monochamus alternatus and lethal wood by Monochamus alternatus,we analyzed thecarbon losses of Pinus Yunnanensis after being Monochamus alternatus attacked. Theresults showed that the carbon losses were concentrated in carbon losses of lethal woodby Monochamus alternatus and carbon losses of NPP. Forest in good health in Nanhua,because of Monochamus alternatus attacked, the carbon loss was0.1214Ct·hm^-2·a^-1.Carbon losses of NPP was0.1210Ct·hm^-2·a^-1which account for99.67%in total carbonlosses and carbon losses caused by Monochamus alternatus feeding only account for0.33%.Forest in poor health in Yuxi, because of Monochamus alternatus attacked, thecarbon loss was3.6465Ct·hm^-2·a^-1. Carbon loss which caused form lethal wood byMonochamus alternatus,account for about91.82%. Because of Monochamus alternatusattacked, carbon losses of NPP was0.2840Ct·hm^-2·a^-1which account for7.79%.Thecarbon losses of feeding by Monochamus alternatus only account for0.39%.（5） Biomass was58.602t·hm^-2.The carbon storage was29.978C t·hm^-2and theleaf NPP were17.243Ct·hm^-2·a^-1in the forest of tianzimiaopo Nanhua county. In theforest of beishan Yuxi county, Yunnan province, the biomass was36.155t·hm^-2and thecarbon storage was18.510C t·hm^-2. The leaf NPP was8.937Ct·hm^-2·a^-1.