摘要
Background:The‘Khasihillsal'forestecosysteminMeghalaya,Indiarepresentstheeasternmostlimitofsaldistribution.Wetestediftreediversityandcompositionalheterogeneityofthisecosystemwashigherthanothersal-dominatedforestsduetomoisterenvironment.Methods:Vegetationwassampledin11transectsof10mwidthandupto500mlengthcovering5.2haarea.Allstems≥10cmgirthatbreastheightwereenumerated.Results:WefoundapatternofmixeddominanceofShorearobusta(sal)andSchimawallichiiandco-dominanceofPinuskesiyaandCareyaarborea.TheShannon'sdiversityindex(H′)was3.395nats.ThisvalueisremarkablyhighandcompetitivetothatofmoistsalforestsofeasternHimalayanfoothillsandsal-dominatedforestsofTripura.AhighvalueofH′wasmanifestedby:a)highspeciesrichness(S=123),b)goodequitability(70.6%),c)‘fair'resourceapportionment,andd)abundanceofrarespecies(84%specieswithlessthanonepercentoftotalindividuals,67%specieswithtwoorlessindividualsha-1and59%specieswithoneorlessindividualsha-1).Thecompositionalheterogeneitywas‘fair'(Whittaker'sβw=3.15).ThepresenceofFagaceaewithsixspeciescommanding4.3%ofimportancevalue(IVI)andofapine(P.kesiya)insalforestwasremarkable.Asmanyas58speciesshowed‘lowdensity(≤10individualsha-1),uniformdispersion',fivespeciesachieved‘higherdensity(>10individualsha-1),uniformdispersion'andsixofthetop10specieswere‘clumped'.Theforestshowedanexponentialdemographiccurveillustrating‘good'regenerationofanexpandingcommunity.Verticalstratificationwassimplewithapoorcanopyandfairsubcanopy,whichtogetherwithlowbasalarea(15.65m2·ha-1forindividuals≥10cmgbh)indicatedloggingofmaturesaltreesinthepast.Conclusions:The‘Khasihillsal'forestecosystemisricherinalphaandbetadiversitythanmostsal-dominatedforests,butpastlogginghasreducedbasalarea.Selectiveremovalofsmal
出版日期
2014年04月14日（中国期刊网平台首次上网日期，不代表论文的发表时间）
