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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(Tectonagrandis L.f.)、绒毛野独活(Miliusa tomentosa Roxb.)和紫矿(Butea mono-sperma Lain.)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。对这些树种的总干物质进行记录,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最多的是阿托伯金合欢、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。图1表4参30。
In this paper, the seasonal changes of the biological elements in litter in five tropical deciduous forests in western India and the seasonal changes of their return to fresh leaves were studied. Five species of Acacia nilotica L., Acacia leucophloea Roxb., Tectonagrandis Lf, Miliusa tomentosa Roxb. And Butea mono-sperma Lain. The concentrations of N, P, Ca, Mg, K and Na in mature leaves, shoots and regenera- tion fractions of litter were investigated in relation to the concentrations of old leaves and young leaves. The total dry matter of these species was recorded and their contents of N, P, Ca, Mg, K and Na were analyzed. Among them, the content of N in Acacia leaves was the highest, while the content of Ca and Mg in acacia leaves was the highest. Leaves containing the most P is Acacia Acacia, Acacia and purple ore, and P is the smallest of Teak and villi wild only. K and Na content in these species no significant difference. It was observed that concentrations of N, P and K varied greatly with seasons but Ca and Mg did not. Only potassium is the most stable of all tree species, and N and P uptake can be used for new leaf growth in the coming year. Nutrients absorbed from old leaves and litter will support new leaf growth and increase soil fertility. Figure 1 Table 4 Reference 30.