Biomass production from naturally growing Melastoma (Melastoma affine, D. Don)

摘要

AstudywasconductedatHoaanFarmingSystemResearchStationofCanthoUniversity,Haugiangprovince,VietnamfromMaytoNovember2004toestimatethebiomassproductionofnaturallygrowingMelastomaaffine,D.Donintheacidsulphatesoilarea.FiveMelastomashrubsof4differentheightclasses(1.0m;1.0-1.9m;2.0-2.9mand2.9m)werecutat15-20cmaboveground.Theediblefoliage(leaves+petioles+40cmofstem)andwoodystemswereharvestedandweighedtomeasurethetotalbiomassyieldsfromshrubsofdifferentheightsandproportionofediblefoliage.Numberofshootsandsub-shoots,averageheightoftheshootsandsub-shootswerecountedandmeasuredoncepermontheachindividualplanttomeasuretheabilityofre-growth.NoMelastomashrubhigherthan2.9mwasfoundinthefields.ThehighestpercentageofedibleDMyieldwasfromMelastomabelow2.0m.Shrubshigherthan2.0mweremoresuitableforfuelwood.Aftercutting,thenumberofshootsandsub-shootswashigherthanthenumberofstumpsandgrewwell.Twentysub-plots(5m*5m)werealsorandomlyselectedandmarkedwithin4mainplots(20m*20m)(5sub-plotspermainplot)forestimatingbiomassproductionperhectareinanareadominatedbyMelastoma.Thetotalfreshbiomassyieldperhawasabout37.2tons.Thebiomassofediblefoliagewas1.5timeshigherthanthebiomassofwoodystems.TheresultsshowedthattheheightofnaturallygrowingMelastomastronglyinfluencedtheyieldofediblefoliageandwoodystems.