抄録
Macropores in soils of agricultural fields make the soils nonuniform and also govern the water movement phenomena occuring there. We examined the pore size which divided macropores from micropores and the sample size when sampling from soils with macropores. The former, we statistically analyzed relationships between saturated hydraulic conductivity and pore characteristics of undisturbed cylindrical soil samples. The latter, we simulated the sample size which represent the crack length in a unit area when sampling soils with cracks. The results of the statistical analysis showed that saturated hydraulic conductivity was correlated best with the porosity for the pores whose equivalent diameter was greater than 0.1〜0.03mm. And, the result of the simulation showed that the representative sample size for the crack length in a unit area had to contain 20〜50 units of mesh. On the basis of such results, we discussed an approach to make clear water movement phenomena in soils with macropores. And, following 3 subjects were proposed to be investigated.
①understanding of macropore system
②water flow in each macropore
③size of block and governing law when averaging water movement phenomena in a field soil.
