Effects of Different Fertilizers on Soil Fertility for Eucalypt Plantations in Leizhou Peninsula

This study examined the effect of organic fertilizer and inorganic fertilizer on soil nutrients and fertility levels.The results showed that in the low fertility soils of Leizhou Peninsula,organic matter content in basalt-latosol soils increased but that in other latosol soils(developed from neritic sediments) declined when Eucalyptus was planted.Significant correlations between soil organic matter content and the growth of Eucalyptus were found,but growth was not significantly influenced by the different levels of the fertilizers applied in this study.As the amount of filtered mud applied increased from 1.5 to 2.5 kg·plant-1,soil organic matter content increased from 0.02% to 0.21% relative to that with a single inorganic fertilizer,and by 0.07% to 0.26% relative to that with no fertilizer.Five years after application of the fertilizers,soil bulk density decreased by 0.01% to 0.22% for the organic fertilizer relative to the inorganic fertilizer;total porosity of the former was increased by 0.1% to 7.1% compared to that of the latter.Overall the results showed that organic fertilizer can improve physical properties of latosol soils and has a significant effect on fertility levels of such soils under eucalypt plantations.