The Potential Minimum Phosphorus Fertilizing for Eucalyptuss camaldulensis,E. grandis and E. tereticornis
- Received Date: 1999-06-01
- Available Online: 2012-03-17
Abstract: A fertilizing experiment was established in March 1989,at Yangxi,Guangdong,China. A randomised block split plot design was employed in which 10 phosphorus rates (0,5,10,15,25,35,50,100,150,200 kg(P)·hm-2 as superphosphate in sub plots randomised within main plots which represented 3 Eucalyptuss species, Eucalyptuss camaldulensis,E. grandis and E. tereticornis . The tree heights were measured at 1,3,6,9,12,21,24,64 months after planting,and DBH at 9,12,21,24,40 and 64 months. The results showed that the tree heights from 1 to 64 months and DBH from 9 to 64 months were significant differences (P 0.01 or P 0.05) between unfertilizing and 9 P treatments,and between 3 Eucalyptuss species. Phosphorus fertilizer can clearly improve the growth of tree heights and DBH,but the improvement was different in phosphorus needs among the 3 tree species,that is,tree heights and DBH measured from 6 to 64 months were significant interaction effect between tree species and phosphorus treatment,and the starting and end of the high effectiveness periods were differences between 3 species. It was suggested that potential lower quantity of phosphorus fertilizer when planting in field,respectively 50~100 kg(P)·hm-2 for E. camaldulensis and E. grandis,and 25~100 kg(P)·hm-2 for E. tereticornis.