Study On The Characteristics Of Litter And Ecological Function Of Different Chinese Fir Forest Management Mode

Chinese fir(杉木)is a timber species which grows quickly and has an important role in southforestry. Ecosystem of Chinese fir artificial forestry is declining seriously because of successiveplantation which restricted sustaining development of Chinese fir artificial forestry.The study onthe decline of soil fertility of Chinese fir plantation started in the eighty’s last century, The problemhas become a deep concern of many scholars with the deepening of the research recent years.From the present situation research report，Chinese fir plantation soil fertility decline and littercomposition, quality, quantity and decomposition conditions have a close relationship. Manyresearches indicated that one of the most important factors which induce soil declining is that thelitter return of Chinese fir is less，The litter decomposition is difficult，Therefore leads to itsnutrient return forest less，The soil nutrient income and expenses resulting imbalance and soilacidification, the ability of self-raising is also limited,. Techniques such as fertilization and scantycutting can improve decomposition condition of forestry litter. But as far as grown forestry isconcerned, these measures are not enough. Therefore, how to pass on ecosystem of Chinese firplantation structure carries on the effective regulation, to try to change the amount of litter, massand composition, promoting litter decomposition, increase litter nutrient return，has become animportant research topic in. the current land degradation of artificial Chinese fir forest pest controlsystem..So，Over the years the task group for Chinese Fir Plantation in the presence of variousecological problems，Based on the importance of digestion and absorption of domestic and foreignscholars on the artificial forest management theory and method，chosing4forest ecosystemmodes—naturally regenerated evergreen broad-leaved forest model, the old-growth Chinese firmodel, abandoned natural regeneration Chiness fir model, the second-generation Chinese firplanted in1993year model—built in Xiqin Teaching Forest Farm in Nanping City as the series ofquadrats, and using located research in the field, Focusing on Chinese fir plantation pattern in thelitter characteristics and ecological function to study. Using artificial simulation method, this paperstudied on Chinese fir forest mode of litter on soil acidification buffering effect and water retention properties, And then tried to reveal the law of the Mechanism of decline of soil fertilityof Chinese Fir Plantation，Establish land degradation of artificial Chinese fir forest pest controlsystems and Restorat Chinese fir Forest Ecosystem and the Chinese fir Reconstruction technique.The results were as follows:（1）The annual litterfall of Chinese fir in various system is2.89～9.56t/hm2，The litterannual Litterfall of various system shows naturally regenerated evergreen broad-leaved forestmodel＞bandoned natural regeneration Chiness fir model＞the old-growth Chinese fir model＞thesecond-generation Chinese fir planted in1993year model. The system of leaf litter litter in apercentage of the maximum，the leaf percentage is53.16%～83.50%，the branch percentage is2.66～18.32%，the fruit percentage is4.57%～36.49%，Other components percentage is1.84%～16.28%. The system of litterfall has obvious seasonal variation. The return of4systems revealssingle-peak type anddouble-peak type. The peak value in the first half of the year occurred mostlyin the May，the second half of the year is in November.（2）The litter amount element nutrient content and volume restitution order basically shows：N＞Ca＞K＞Mg＞P，the old-growth Chinese fir model, abandoned natural regeneration Chinessfir model, the second-generation Chinese fir planted in1993year model have a low nutrientcontent in brand and fruit. Naturally regenerated evergreen broad-leaved forest model has a highNutrient content in leaf and other components，fruit and brand have a low level.4systems of5kinds of elements in the annual return have obvious differences. The5kinds of elements of theabandoned natural regeneration Chiness fir model（173.78kg/hm2）and Naturally regeneratedevergreen broad-leaved forest mode（l147.00kg/hm2）have a large amount of return，The5kindsof elements of the second-generation Chinese fir planted in1993year mode（l65.44kg/hm2）andthe old-growth Chinese fir model（90.69kg/hm2） have a low amount of return.（3）The litter amount trace elements content order basically shows：Mn＞Fe＞Al＞Zn＞Cu，the leaf and other components of the4system have a high trace elements content，the brandand fruit have a low trace elements content. The volume restitution of trace elements contentbasically shows：Mn＞Fe＞Al＞Zn＞Cu.The system of trace elements in return in a year havecertain fluctuation, The return of4systems reveals single-peak type anddouble-peak type. he peakvalue in the first half of the year occurred mostly in the May，the second half of the year is inNovember. （4）The total amout of litterfall on the gurond of naturally regenerated evergreenbroad-leaved forest model is largest. The second-generation Chinese fir planted in1993yearmodel have a lowest amout of litterfall on the gurond. The largest volume of forest litter on theground is naturally regenerated evergreen broad-leaved forest model.The second is the abandonednatural regeneration Chiness fir model, the second-generation Chinese fir planted in1993yearmodel is the lowest.The amout of leaf on the groud in the4system is0.88～2.10t/hm2,brand is0.67～1.33t/hm2,fruit is0.06～1.61t/hm2, Other components is0.09～0.42t/hm2.The litterbiomass peak is the single-peak type,and the peak appeared in the April.（5）The litter amount on the ground element nutrient content and volume restitution orderbasically shows：N＞Ca＞K＞Mg＞P。The4systems of5kinds of elements in the annual returnhave obvious difference. The abandoned natural regeneration Chiness fir model（97.39kg/hm2）、naturally regenerated evergreen broad-leaved forest model（96.24kg/hm2） and the old-growthChinese fir model（76.97kg/hm2） have a high return in nutrient，the second-generation Chinesefir planted in1993year model（37.23kg/hm2） has a low level. The system existing litterfall andnutrient storage model is single peak type（April） except the second-generation Chinese firplanted in1993year model.（6）The litter amount on the ground of trace elements content order basically shows：Mn＞Al＞Fe＞Zn＞Cu.The system existing litterfall and Trace element storage model is single peaktype（April） except the second-generation Chinese fir planted in1993year model.（7）The turnaround time of different system of litter deconmposition were abandonednatural regeneration Chiness fir model（1.25years）, naturally regenerated evergreen broad-leavedforest model （1.74years）, the second-generation Chinese fir planted in1993yearmodel(1.98years),the old-growth Chinese fir model (2.41years).The turnaround time of abandonednatural regeneration Chiness fir model and naturally regenerated evergreen broad-leaved forestmodel were faster than the turnaround time of naturally regenerated evergreen broad-leaved forestmodel and the old-growth Chinese fir model.（8）The totally water capacity of abandoned natural regeneration Chiness fir model wasmaximum of0.39mm; The totally water capacity of naturally regenerated evergreen broad-leavedforest model was minimum of0.21mm; The totally water capacity of another models were0.27mm of the old-growth Chinese fir model and0.22mm of the second-generation Chinese fir planted in1993year model fron large to small. The totally water capacity of abandoned naturalregeneration Chiness fir model was significantly greater than the other models, this is directlyrelated to the highest litter accumulation of abandoned natural regeneration Chiness fir model inthe four models;The totally water capacity of naturally regenerated evergreen broad-leaved forestmodel and the second-generation Chinese fir planted in1993year model was relatively smalldifferences; The totally water capacity of naturally regenerated evergreen broad-leaved forestmodel was minimum, this is directly related to less litter accumulation of naturally regeneratedevergreen broad-leaved forest model than other.（9）The pH value range is4.0~5.0in the4system.The abandoned natural regenerationChiness fir model and the old-growth Chinese fir model have a high pH value than the other2systems. The pH value of the4system is：the old-growth Chinese fir model>abandoned naturalregeneration Chiness fir model>naturally regenerated evergreen broad-leaved forest model, theold-growth Chinese fir model>the second-generation Chinese fir planted in1993year model.Thenaturally regenerated evergreen broad-leaved forest model has the highest conductivity in the4system，and the second is the second-generation Chinese fir planted in1993year model，Theabandoned natural regeneration Chiness fir model is the lowest.The naturally regeneratedevergreen broad-leaved forest model has the highest Inorganic ion content，conductivity，Na+、Mg2+NO、3、K+Extraction volume.The second is abandoned natural regeneration Chiness firmodel，the second-generation Chinese fir planted in1993year model is the lowest.The hesecond-generation Chinese fir planted in1993year mode has the highest Content of Ca2+，thesecond is abandoned natural regeneration Chiness fir model and the old-growth Chinese firmodel，The naturally regenerated evergreen broad-leaved forest model, the old-growth Chinese firmodel is the lowest.