Study On The Evaporation And Transpiration In Dry Land In The Middle Of Shanxi

To study on the characteristics and influencing factors of water use structure and the mechanism of high yield and water use efficiency in dry land, the experiment of the soil evaporation and transpiration was conducted in Shouyang of Shanxi province from 2013 to 2014. Through 2 years’ experiment, we obtained the following conclusions.1. Plastic mulching, fertilization and subsoiling increased evapotranspiration of maize field. The evapotranspiration of maize field with plastic mulching was 2.73% to 4.13% higher than that without mulching. The evapotranspiration increased with the increase of fertilizing amount. There was no significantly different between maize field with organic fertilizer applying and that with chemical fertilizer applying when the amount of nitrogen was equal. The evapotranspiration of maize field in subsoiling was 6.68% to 7.29% higher than that of convention. Compared with maize field without mulching, the evapotranspiration of that with straw mulching had no significant difference. The planting density had no significant effect on evapotranspiration.2. Mulching, fertilization and the increase of planting density reduced the soil evaporation obviously in dry land. Compared with maize field without mulching, the soil evaporation of that with plastic mulching and straw mulching decreased by 35.4% to 39.7% and 17% to 57.52% respectively. And with the increase of straw mulching amount, the soil evaporation decreased. Fertilization could significantly promote crop growth and reduce soil evaporation. The soil evaporation of maize field with organic fertilizer applying was lower than that with chemical fertilizer applying when the amount of nitrogen was equal. Compared with conventional planting, the increase of planting density reduced soil evaporation of maize field by 2.68% to 15.38%. And the soil evaporation increased with the raise of planting density. The soil evaporation of maize field in subsoiling was 2.99% to 6.1% lower than that of convention. Correlation analysis indicated that the soil evaporation showed positively correlations with surface temperature and soil moisture and showed a negative correlation with leaf area index.3. Mulching, fertilization and the increase of planting density improved the transpiration and the ratio of transpiration and evaporation(E/T) of maize field. The transpiration and E/T of maize field with plastic mulching were 31.99% to 33.47% and 106.59% to 118.75% higher than that without mulching respectively. The transpiration and E/T of maize field with straw mulching were 10.75% to 27.13% and 33.44% to 175.97% higher than that without mulching respectively. Compared with maize field without fertilizer, the transpiration and E/T of maize field with chemical fertilizer applying improved by 4.44% to 26.57% and 6.33% to 52.08% respectively and the transpiration and E/T of maize field with organic fertilizer applying that were higher than maize field with chemical fertilizer when the amount of nitrogen was equal improved by 7.12% to 41.93 % and 11.92% to 127.41% respectively. Compared with conventional planting, the increase of planting density improved the transpiration and E/T of maize field by 4.02% to 14.15% and 6.89% to 34.9% respectively. Subsoiling maize field also increased the transpiration by 2.99% to 6.1%.4. Mulching and fertilization could significantly improve the yield and water use efficiency(WUE) by effectively suppressing soil invalid evaporation and increasing the productive water use(the transpiration). The yield and WUE of maize field with plastic mulching were respectively.57.43% to 76.76% and 51.22% to 71.99% higher than that without mulching. The yield and WUE of maize field with straw mulching were 15.83% to 36.39 % and 15.9% to 45.89% higher than that without mulching respectively. Straw mulching amount, the increase of which led to raise of WUE, had no significant influence on the yield. The yield and WUE improved with the increase of fertilizer amount. The yield and WUE of maize field with organic fertilizer applying were higher than that with chemical fertilizer applying when the amount of nitrogen was equal. Subsoiling maize field increased the yield and WUE by 10.17% to 34.44% and 3.27% to 25.3% respectively. Increase the planting density appropriately can improve the yield and WUE of maize field. The yield and WUE were highest when plant 67500 maize per hectare in conventional tillage and were 3.29% and 2.25% higher than that of convention.