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以4年生、8年生、13年生尾巨桉林为研究对象,测定并计算其鲜叶、凋落叶和表层土壤的养分含量、内吸收率及碳氮磷化学计量比(C:N:P).结果显示:叶片C、N、P含量变化范围分别为486.0-508.56、13.31-15.46、0.60-0.84 mg/g,凋落物为462.55-499.9、8.20-11.51、0.29-0.51 mg/g,土壤为1.87-2.78、0.17-0.33、0.12-0.18 mg/g;植物C、N、P含量显著高于土壤,不同林龄间叶片C、N含量差异显著(P<0.05),叶片、凋落叶P含量差异均极显著(P<0.01);尾巨桉N、P内吸收率分别为31.37%、42%,P内吸收率大于N内吸收率;叶片重吸收效率表现出了随林龄增大而呈下降的趋势,且不同林龄尾巨桉N:P>16.研究结果表明该地区尾巨桉的生长限制因子为P元素,有助于为滨海沙地人工纯林植物群落制定合理的营林规划、施肥评估标准提供依据.
The four-year, eight-year-old and 13-year-old Eucalyptus urophylla trees were used as the research object to measure and calculate the nutrient contents, internal absorption rate, carbon and nitrogen phosphorus stoichiometry (C: N: P) The results showed that the contents of C, N and P in leaves varied from 486.0-508.56, 13.31-15.46 and 0.60-0.84 mg / g respectively, litterfalls were 462.55-499.9, 8.12-11.51 and 0.29-0.51 mg / g, 1.87-2.78,0.17-0.33,0.12-0.18 mg / g. The contents of C, N and P in plants were significantly higher than those in soils. The contents of C and N in leaves of different ages were significantly different (P <0.05) (P <0.01). The N and P internal absorption rates of E. grandis were 31.37% and 42%, respectively, and the P internal absorption rate was higher than N internal absorption rate. The leaf reabsorption efficiency exhibited a trend of increasing with increasing age The results showed that the growth limiting factor of E. grandis was P element, which would be helpful to establish a reasonable camp for artificial pure forest in coastal sandy land Forest planning, fertilization evaluation criteria provide the basis.