Rain can leach plant elements to the
plantation soil. lt was estimated that 20, 10,
0.5 and 1.5 kg ha-l of K, N, P and Mg were
leached by 2,450 mm rain into the soil.
However, Plant nutrient element that cyclic
in rubber plantation soil also depends on
soils and fertilizer managements. lncreasing
K fertilization rate also increased the K
content in leaf litter fall. Calcium and N as
macro element were the most recycled leaf
nutrients to the soil via litter fall. Whereas
the concentrations of B, Fe and Mn in fall
leaves are higher tilran in 6-month-rubber
leaves. (Table 4.) Potassium, followed by P
was nutrients with the highest retranslocation
rate. Potassium was the most export
nutrient by harvested rubber, and this amount
was higher than that transferred to the soil
by the leaf litter fall