THE CHARACTERS AND EFFECTS OF AVAILABLE PHOSPHORUS IN DAHURIAN LARCH-MANCHURICA ASH MIXED SEEDLING STAND

Dahurianlarch(Larixgmelinii)isamaintreesPeciesinartificialstandsandManchuriaash(Fnainusma:dehurica)isavaluabIehardwoodsPeciesinti1eforestareaofnortheastChina.SomestUdiesrevealedthatthemixedstandbythetwospecieshadpositivemixedeffectSandnutritionrelationshipwasoneofthemaincausesforthepositiveeffects.lnsomeresearches,itwasfoundthatinline-belttwoflarch-ashmixedstand,theconcentra-tionofavailablephosphorusofsoilinlarchbeltwas2ntimesoftl1atinashbelt.Itisdeducedthatinsuchmixedstandtheashcanabsorbmo…

The characters and effects of available phosphorus in dahurian larch-Manchurica ash mixed seedling stand

The characters and effects of available phosphorus in dahurian larch-Manchuria ash mixed stand was analyzed through measuring available phosphorus of rhizosphere-soil, phosphorus of living and withered leaves and tree height The study results showed that the phosphorus of living leaves of larch was equal to or less than that of ash. For 5-year-old larch-ash ndxed seedlings stand,larch has more available phosphorus in soil, which is not caused by the decomposition of leaves, but the acts of root. The root of larch activates available phosphorus by acidoid fme rhisosphere-soil. At the site with a high concentration of available phosphorus (grondg bean before), 5 aged larch grows faster than the same aged ash in pure stand. The ash at the site with a high concentration of available phosphorus at 20 cm soil layer showed a trend to grow over larch, and at the site, with a low concentration of available phosphorus at 20 cm soil layer, had a trend to be suppressed by same aged larch.