| The study area was selected in the Greater Hinggan Mountains region with the fragile low-quality stand. We reformed Birch coppice and broadleaf mixed secondary forest mainly by adopting banded and massive ways of clear cutting. And we respectively considered modified forest land redistribution of precipitation, litter layer and soil layer of hydro-ecological function as the research object.It analyzed the influence of different clear-cutting reformation to two kinds of low-quality stand on soil physical properties, litter volume, water holding capacity (rate), effectively held (depth) and low-quality forest canopy interception of precipitation amount (rate). The main results were as follows,(1)Bandwidth of6m to18m clear-cutting belt no litter decomposition layer volume accounts for less than half a litter decomposition level of volume in Birch coppice and broadleaf mixed secondary forest,and the same as an area of5m X5m to30m X30m block areas. Birch coppice low-quality stand no litter decomposition volume ranked as banded>massive clear-cutting; Half a litter decomposition volume ranked as banded>massive clear-cutting; Total litter volume ranked as banded>massive clear-cutting, broadleaf mixed secondary forest no litter decomposition volume ranked as banded<massive clear-cutting; Half a litter decomposition volume ranked as banded<massive clear-cutting; Total litter volume ranked as banded<massive clear-cutting.(2)Birch coppice low-quality forest no litter decomposition capacity (rate) ranked as banded> massive clear-cutting; Half a litter decomposition capacity (rate) ranked as banded>massive clear-cutting; Total litter water holding capacity (rate) ranked as banded>massive clear-cutting. Broadleaf mixed secondary forest no litter decomposition capacity ranked as banded>massive clear-cutting., the water holdup ranked as banded<massive clear-cutting; Half a litter decomposition capacity ranked as banded<massive clear-cutting.Water-holding capacity ranked as banded>massive clear-cutting; Litter total capacity ranked as banded<massive clear-cutting, the total litter water-holding rate ranked as banded>massive clear-cutting.(3)Birch coppice low-quality forest no litter decomposition effectively held (depth) ranked as banded>massive clear-cutting; Half amount of litter decomposition effectively held (depth) ranked as banded>massive clear-cutting; Total amount of litter effectively held (depth) sorting: ranked as banded>massive clear-cutting. Broadleaf mixed secondary forest no litter decomposition effectively held (depth) ranked as banded<massive clear-cutting; Half amount of litter decomposition effectively held (depth) ranked as banded>massive clear-cutting; Total amount of litter effectively held (deep) ranked as banded<massive clear-cutting.(4)Two different forest stand with different reformation performed the same change trend of water holding capacity with the immersion time. Forests litter water holding capacity and the soak time meet the logarithmic curve as follows,the relationship could be discribed as S=mln(t)+n. Two different forest stand with different reformation performed the same change trend of litter bibulous rate trend along with the change of immersion time. Forests litter water absorption rate and immersion time meet have been curve as follows,the relationship could be discribed as V=at-1.(5)Contrasting Birch coppice low-quality forest to check plots, the soil water content decreased with soil moisture content ranked as banded<massive clear-cutting; Soil bulk density ranked as banded>massive clear-cutting; Total porosity declined slightly, with the total porosity ranked as banded>massive clear-cutting. Contrasting broadleaf mixed secondary forest to check plots, soil water content decreased with soil moisture content ranked as banded>massive clear-cutting; Soil bulk density ranked as banded>massive clear-cutting; Total porosity declined slightly with the total porosity of ranked as banded>massive clear-cutting.(6)During the observation period, atmospheric precipitation was in the majority with small to moderate rain, and it mainly concentrated in July and August. Low-quality stand reunited a total rainfall of209.81mm. Birch coppice and broadleaf mixed secondary forest canopy intercept total amount was20.10mm and24.56mm respectively with respectively over the same period reunite around9.58%, and9.58%of total rainfall.The average entrapment rate of broadleaf mixed secondary forest was much bigger than Birch coppice low-quality birch. Birch coppice low-quality stand reunite the total amount of rainfall and interception by canopy as follows,the relationship could be discribed as Y=-0.0003X3+0.0142X2-0.142X+1.1525. broadleaf mixed secondary forest outside the total amount of rainfall and interception by canopy as follows,the relationship could be discribed as Y=-0.0004X3+0.004X2-0.0195X+0.9761. Low-quality stand canopy interception rate has an obvious seasonal change with the largest canopy interception rate values for June, and then July, and last August.These forest hydrology regularity could be good to select the rational reformation of function of forest water conservation, but also reveal the relationship between forest and water conservation and forest hydrology ecological function in the Greater Hinggan Mountains. It provided the correct theory basis of the health management to the forest,eological environment construction and promoting the rapid development of local economy of the Greater Hinggan Mountains. |
PDF Full Text Request