三瓶演習林内の落葉広葉樹林における物質循環に関する研究(V) : 林内の降水量および養分量

This paper deals with the rain fall, through fau and stem flow in a deciduous broad-leaved forest at Sanbe Forest.
1. A high correlation was observed between through fall(y) and rainfall(x) in every plot. The relations may be written by the following regression equations.
P-1:y = 0.719x-0.689 P-2:y = 0.844x-1.658
P-3:y = 0.674x-1.445 P-4:y = 0.731x-3.558
P-5:y = 0.759x-7.223 Watershed:y = 0.766x-1.191
2. The relationship between stem flow and rain fall showed a fairly high correlation. The amount of stem flow became larger with an increase in diameter of tree.
3. The concentrations of potassium, calcium, and magnesium in through fall showed a trend to become higher in a fallen season. The nutrient concentrations in rain fall and stream water were constant during the measuring period.
4. The amount of potassium supplied to forest floor by through fall was 20.95-72.46 kg/ha, which was the largest among those of nutrient elements. The amounts of other nutrient elements were as follow; Ca 12.94-31.31kg/ha, Na 28.81-32.69kg/ha, Mg 8.52-16.00kg/ha, N 2.04-3.24kg/ha, and P 0.59-1.06kg/ha.