Abstract: Taking the cultivated soils in typical black soil region of Northeast China as test objects, and by using dye tracer and double-ring infiltrometer techniques and photograph interpretation method, this paper measured and analyzed the dye-stained width and dye-stained coverage of soil transverse and longitudinal sections as well as the field maximum dye-stained depth, aimed to approach the water flow movement pattern and distribution characteristics in test soils. At soil depth 0-15 cm, matrix flow was the main soil water flow movement pattern; at depth 15-20 cm, lateral flow was observed, and the average dye-stained width and dye-stained coverage reached their maximum, being 23 cm and 20.73 %, respectively. At depth 20-67 cm, the main soil water flow movement pattern was macro-pore flow, with cracks and macro-pores as the main preferential routes. The cracks at depth 20-35 cm made the preferential flow have distinct surrounding characteristics, and the macro-pores at depth 40-67 cm were the main preferential routes. Due to the existence of the preferential routes of cracks and macro-pores, the migration velocity of water in soil increased by 4.5 times, which could not only cause water loss, but also accelerate the migration of pesticides to ground water. It was suggested that these preferential routes should be decreased or eliminated during the cultivation and management on cultivated typical black soils.

Key words: typical black soil, preferential flow, dye tracer, surrounding characteristics, tillage method, quadric sowing soybean, photosynthetic characteristics, economic benefit.