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本文对印度西部5种热带干落叶林中凋落物里生物元素的季节性变化和它们返回到新鲜叶中季节性变化进行研究.对5个树种:阿拉伯金合欢(Acacia nilotica L.)、金合欢(Acacia leucophloea Roxb.)、柚木(Tectona grandis L.f)、绒毛野独活(Miliusa tomentosa Roxb.)和紫矿(Butea mono-sperma Lam.)中凋落物的成熟叶、枝和再生部分的N、P、Ca、Mg、K和Na的浓度,以及老叶和幼叶中浓度间的关系进行调查.对这些树种的总于物质进行记录,并分析它们所含的N、P、Ca、Mg、K和Na的含量.其中阿拉伯金合欢叶子中N的含量最高,而金合欢的叶子里Ca和Mg含量最高.叶中含P最多的是阿拉伯金合欢、金合欢和紫矿,而含P最少的是柚木和绒毛野独活.K和Na含量在这些树种中没有明显的区别.观察发现,N、P和K的浓度随季节变化大,但Ca和Mg则不然.唯有钾在所有树种中都是最稳定的,吸收N和P可以用于来年新叶的生长.从老叶和凋落物中吸收的营养会支持新叶的生长,并增加土壤的肥力.“,”The Litter nutrient concentrations of N, P, Ca, Mg, K and Na in mature leaves, twigs and reproductive parts and their relationship between senescent and young leaves were investigated in five forest species: Acacia nilotica, Acacia leucophloea. Tectona grandis, Miliusa tomentosa and Butea monosperma in Indian tropical dry deciduous forest in Western India.. Total dry matter of plant species was recorded and analyzed for N, P, Ca, Mg, K and Na. A. Nilotica had the highest concentrations of N in leaf, while A. Leucophloea had the highest concentrations of Ca and Mg in leaf. The highest concentrations of P in leaf were found in A. Nilotica, A. Leucophloea and B. Monosperma where as lowest in T. Grandis and M. Tomentosa. No significant differences in K and Na were registered among the species. A marked seasonal variability was observed in the concentrations of N, P and K, except for Ca and Mg. Potassium is the single element that undergoes leaching and mobilization in all species. Resorped N and P can be used for the production of fresh leaf in the following annual cycle. Nutrient resorption and retranslocation from senescent leaves and litter supports the production of new foliage and increase the fertility of soil.