Changing Characteristics of Salt Accumulation Patterns in the Soil Surface

Research Project

Project/Area Number	60560241
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	農業土木
Research Institution	University of Tsukuba
Principal Investigator	ABE Yukuo University of Tsukuba, 農林工学系, 講師 (70015808)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥1,800,000 (Direct Cost: ¥1,800,000) Fiscal Year 1986: ¥200,000 (Direct Cost: ¥200,000) Fiscal Year 1985: ¥1,600,000 (Direct Cost: ¥1,600,000)
Keywords	Salt Accumulation In The Soils / Curves Of Drying Rate Of Soils / Solution Movement In The Soils / 土壌物理
Research Abstract	It was recognized that salt accumulation curves represented relation between evaporation from soil surface and concentration of soil suspension at each divided layers have the remarkable inflection point named point of A by the study which was performed to determine the salt accumulationpatterns in the frying process of soil specimens saturated with NaCl solution. In order to explain this phenomenon additional experiments for salt accumulation were performed at the different drying conditions. And some kinds of experiments related with salt accumulation were tried; i.e. patterns of drying rate curves to soil solution and movement characteristics of soil solution. The following results were obtained. 1. Volume of evaporation decreased in the increase of drying temperature at the inflection point of A. But, the difference of concentration of soil solution did not have an effect on the volume of evaporation. 2. The effect of differnces in the kinds of soils and concentration of soil solution on the drying characteristics of soil s during the process of salt accumulation was studied experimentally using soil columns. It was recognized that the configuration of curves of the drying characteristics of soils varied with the differnce in these parameters. 3. The movement of soil solution was studied by four kinds of curves; i.e. water content distribution at the different divided layers and at the different drying levels, and relation between accumulated drying velocity of divided layers and drying level, and relation between drying velocity at each divided layer and drying level. It was recognized that these curves were effective to study the salt accumulation and that experimental accuracy is need to increase.