Comparison Of Soil Quality Under Pinus Tabulaeformis Monocultures And P. Tabulaeformis And Quercus Mongolica Mixtures In Western Liaoning Province

In this thesis, the forestland of Pinus tabulaeformis and Quercus mongolica mixture,which is very few in western Liaoning Province, is taken as the study object while theadjacent forestland of pure P. tabulaeformis plantation as control to study its directedamelioration of soil quality. The would be very helpful in the sustainable management of thepure P. tabulaeformis plantations.A comprehensive evaluation of the soil quality is made after the soil physical, chemicalproperties and some soil enzyme activities under the mixed-stands of P. tabulaeformis and Q.mongolica are compared with those of P. tabulaeformis pure plantation. The preliminaryresults are as follows:1. Soil physical propertiesMixed-stands of P. tabulaeformis and Q. mongolica is better than pure P. tabulaeformisin bulk density, porosity and soil water content.Compare with P. tabulaeformis pure plantation, mixed-stands of Pinus tabulaeformis andQuercus mongolica is better in improving the soil structure.2. Soil chemical propertiesMixed-stands of P. tabulaeformis and Q. mongolica is better than pure Pinustabulaeformis in soil organic matter, total P, total N, total K and available P. But it not veryevident in total K.3. Soil enzyme activityMixed-stands of P. tabulaeformis and Q. mongolica is better than pure P. tabulaeformisin urease activity, catalase activity and phosphatase activity. Especially in surface, soil qualityof the Mixed-stands of P. tabulaeformis and Q. mongolica is better than pure P. tabulaeformis.The change is more conspicuous in the surface soil. The soil improving effect in surfacesoil depth is better than in lower depth because of litter in plantations mainly concentrated onthe soil surface.4. Analysis and comprehensive evaluation of soil qualityA comprehensive evaluation of the soil quality is made by factor analysis using SPSS.The result is that P. tabulaeformis and Quercus mongolica mixture is better than pure P.tabulaeformis in soil improvement.