|Budget Amount *help
¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 2000 : ¥400,000 (Direct Cost : ¥400,000)
Fiscal Year 1999 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1998 : ¥2,000,000 (Direct Cost : ¥2,000,000)
Nature is destroyed by disordered development of cities and farmland. The land deprived of vegetable causes soil loss and degradation. And, the muddy water generated from that land brings about secondary environmental destruction such as water pollution in the downstream basin. This paper examines the treatment effects of artificial filter materials and water purification materials on the improvement of the muddy water generated from land development activities. Suspended solids can be removed fairly well by combining artificial filters in various modes. However, the clogged conditions of gaps become a trouble to artificial filter materials. It has been proved that combinations of water purification materials and artificial filter materials have sufficient treatment effects on the purification of muddy water. Furthermore, it is considered that muddy water can be treated more effectively by combining these materials with existing facilities such as a settling basin.
It was experimented
and was examined using the PAC of water purification medicine. The aggregation is promoted the paddy soil by using soil conditioner. And, the soil aggregate destruction by the impulsive force of the raindrop is prevented by the increase of the undrained shear strength of soil. However, there is no rise of the effect, when it is not more effective, as it is done, if the soil conditioner does this concentration thick, and when any fixed concentration is exceeded. Permeability of the soil, improvement of the drainage, improvement on the harrowing can expect that the PAC is added to the paddy soil. In addition, soil aggregate increases on the soil loss by run-off, and it is reduced by the development of the granular structure. In actual field, it is necessary to carry out whether it can expect the effect of the PAC how much and further examination.