| Abstrakt: |
This scientific research has determined the water demand of soybean in different hydrological years to overcome problems such as the lack of water for the growth and development of grain crops. Water shortage is caused by low precipitation in the western part of Heilongjiang Province and the high incidence of drought. Drip irrigation, sprinkler irrigation and other irrigation models and irrigation systems were established and the impact of climate change on the water demand law of soybean growth was analyzed in the semi-arid areas in the western part of Heilongjiang Province. According to the meteorological data of Heshan Farm of Heilongjiang Province's Jiusan Administration Bureau from 1951 to 2018, the main parameters of soybean crop growth and the field soil layer data, the Mann-Kendall development trend test method was used to analyze the change trend of climate factors during the soybean growth period, and the CROPWAT model was used to analyze the change trend of water demand, effective rainfall and irrigation water flow throughout the year and each growth period. On this basis, the coupling degree of effective rainfall and soybean growth demand in different hydrological years was compared, and the corresponding irrigation scheme was determined. The results showed that the monthly average temperature in the whole growth period of soybean increased significantly, while the monthly average wind speed decreased significantly, and the demand for soybean decreased with the rate of 9.15 mm/10 years. The water consumption in the wet year was 396.06 mm, the water consumption in the normal year was 390.65 mm, the water consumption in the dry year was 420.21 mm, and the water consumption in the dry year was 459.96 mm. In different hydrological years, the coupling degree of local effective rainfall and soybean water demand shows a trend of increasing first and then decreasing. Under sprinkler irrigation conditions, the irrigation quota was 68.4 mm in the normal year, 121.1 mm in the dry year and 175.9 mm in the extremely dry year. Under the condition of drip irrigation, the irrigation quota in the normal year was 66.3 mm, the irrigation quota in the dry year was 111.6 mm, and the irrigation quota in the extremely dry year was 151.5 mm. According to the irrigation quota under different irrigation conditions, the effective rainfall in other hydrological years in the region is difficult to meet the water demand for soybean growth, except for the wet and flat years. Therefore, in different hydrological years, proper irrigation should be carried out at the flowering and podding stages of soybean to ensure high and stable yield. [ABSTRACT FROM AUTHOR] |
