Characteristics Of Soil Water And Salt Movement Of Greenhouse Soil

Some research about greenhouse soil of Shuangliu in Sichuan province was studied. The soil column experiment by different infiltration process with different water qualities and different irrigation modes in laboratory was conducted. The variations in the characteristics of the content of water, salt ions and the change regularity of electrical conductivity (EC) value were analyzed. And Soil water characteristics under the condition of protected cultivation were analyzed by measuring soil water constant. And the influence of Soil Water movement by Protected cultivation were analyzed by Soil hydraulic properties. The main results were as the bellowing:1. Soil capillary porosity and available water content increased in 0-40cm soil layer under the condition of protected cultivation. The physical property of soil water differences in profile in greenhouse soil was bigger than in the open-air soil. Soil total porosity in 20-40cm soil layer was 52.72% (greenhouse soil) and 46.87% (open-air soil) respectively, and the difference was significant at the 99% confidence level. And in 0-20cm, 40-60cm soil layer were 54.94% (greenhouse soil) and51.35% (open-air soil), 43.29% (greenhouse soil) and 46.18% (open-air soil) respectively, and the difference was significant at the 95% confidence level. Soil capillary porosity and field capacity in 0-20cm soil layer were 44.08% (greenhouse soil) and 41.31% (open-air soil), 42.08% (greenhouse soil) and 39.31% (open-air soil) respectively, and there was no significant difference; And in 20-40cm and 40-60cm soil layer were 43.57% (greenhouse soil) and 39.15% (open-air soil), 41.57% (greenhouse soil) and 37.15% (open-air soil),31.30% (greenhouse soil) and 38.00% (open-air soil) respectively, and the difference was significant at the 99% confidence level. Wilting water level in 0-20cm, 20-40cm, 40-60cm soil layer were 9.64% (greenhouse soil) and 16.35% (open-air soil), 12.61% (greenhouse soil) and 16.69% (open-air soil), 12.44% (greenhouse soil) and 17.64% (open-air soil) respectively, and he difference were significant at the 99% confidence level. Available soil water amount in 0-20cm and 20-40cm soil layer were 32.44% (greenhouse soil) and 22.96% (open-air soil), 28.96% (greenhouse soil) and 20.46% (open-air soil) respectively, and the difference was significant at the 99% confidence level. And in 40-60cm soil layer was 18.86% (greenhouse soil) and 20.36% (open-air soil) respectively, and there was no significant difference.2. The soil moisture diffusivity in greenhouse were changeable from 0.02 to 3.78cm²/min. There was spatial variability in soil moisture diffusivity. The highest soil moisture diffusivity occurred in 20-40cm soil layer, while the lowest in 40-60cm soil layer in greenhouse soil. The relationship between soil moisture diffusivity and soil water content in every soil layer was sharp positive exponential function, and these relationships were significant by statistical analysis(p<0.01). The relationship between Boltzmann parameters and soil water content in every soil layer was sharp positive qudratic function. Hydraulic conductivity was differences in profile in greenhouse soil, and the hydraulic conductivity was higher in the surface(0-20) than lower layer(20-40cm, 40-60cm)3. The variation of the water in the soil profile mainly focused on 0-20cm soil layers after irrigation, which was especially strong in the beginning 5 days of the irrigation. The water content in the soil profile was significantly affected by different quantity of irrigation and with small variation with ascending quantity of irrigation. The desalting region was formed in 0-20cm soil layers, while collection salt region was in 20-30cm soil layers. The quantity of irrigation had little effect on the depth of soil cumulative.4. The influence of irrigation quantity for soil salt ions in greenhouse was difference. And the influence of irrigation quantity for main soil salt ions about greenhouse soil of Shuangliu in Sichuan province was shown as: the content of Ca²⁺ was also affected by the quantity of irrigation, which in 10-40cm soil layers increased firstly and then decreased, while a reverse tendency was manifested in 50cm soil layer. However, the content of SO4 "was scarcely affected by the quantity of irrigation.