Characteristics Of Soil Moisture-Salt-Heat Transfer And Evaluation Of Irrigation Effect Under Intercropping And Border Furrow Irrigation Pattern

With the development and progress of agricultural production, the traditional agriculture of resource consumption type has begun to gradually transform and forward to the technical efficiency. Therefore, the efficient use of agricultural resources has become the focus of agricultural production. Aimed at the present situation including serious waste of irrigation water for conventional irrigation pattern of wheat/maize intercropping, soil salinization and crop water use efficiency is too low and so on in Hetao Irrigation District of Inner Mongolia. This study integrates wheat/maize intercropping for border furrow irrigation technology with ridge furrow irrigation technology. The characteristics of soil moisture-salt-heat transfer during freezing and thawing period after autumn irrigation were studied. The suitability of soil moisture, salt and heat conditions in the spring sowing period for planting wheat and maize was systematically evaluated,also the suitable autumn water quantity was determined. Comparative study on soil moisture-salt-heat transfer characteristics and crop growth indexes, yield and water use efficiency for conventional intercropping and border furrow irrigation technology. Based on field measured datas, the soil infiltration parameters and irrigation quality of different irrigation pattern were studied by the SIRMOD model, also the irrigation effect of border furrow irrigation technology was evaluated. The main conclusions are as follows:(1) Study on characteristics of soil moisture-salt-heat transfer during freezing and thawing period under autumn irrigation and the soil conditions at spring sowing period, 1500m3·hm-2 autumn irrigation quota can meet the required for spring sowing and seedling growth for spring wheat and maize ditching film, reached the effect of water saving to the maximum extent.(2) The soil surface of 0-10cm has been in a state of salt accumulation during the whole growth period, and there was no significant difference in deeper soil salt content between maize furrow irrigation and border irrigation under the irrigation water leaching, and no stress on normal growth of maize. The soil water potential reduced by salt after irrigation, and the soil moisture content of 0-60cm was significantly higher than border irrigation, which was conducive to the growth of maize.The border furrow irrigation wheat soil salt content of 0-40cm was significantly lower than conventional irrigation at intercropping symbiosis period. The soil moisture content of 0-60cm was less than conventional border after jointing stage, which also contributed to the reduction in wheat yield of the main factor.(3) Soil moisture content was an important factor affecting the soil temperature,the pattern of border furrow irrigation effectively improving the soil temperature at the early growth stage of maize, accelerating the process of maize growth, at the same time, the soil was dry, making the root get drought hardening development more developed, which laied the foundation for maize yield of furrow irrigation.(4) Growth effect of crop edge was affected by the growth distribution of root.Furrow maize root distribution of level and vertical content were significantly greater than border irrigation, and wheat root content of conventional border irrigation was significantly greater than border furrow irrigation at growth stage.It was significantly influenced by edge effects limit for maize border irrigation at early growth stage, and with the rising of temperature and termination of wheat boundary line competitive advantage, the maize growth index for two irrigation patterns reached a similar level.Border furrow irrigation wheat growth process affected significantly by edge effect for negative, after heading stage, the edge advantage was obvious for conventional border wheat, and each growth index was significantly higher border furrow irrigation.(5) Compared with conventional irrigation,the border furrow irrigation significantly increased the water use efficiency of crops,and irrigation water saved more than 30%, and average yield of maize increased by about 14%, wheat yield decreased by about 7%.Comprehensive consideration, in the tense situation of agricultural water in Hetao Irrigation District, the application for wheat/maize intercropping border furrow irrigation was recommend.(6) Based on field measured datas, the soil infiltration parameters and irrigation quality of different irrigation pattern were studied by the SIRMOD mode. Results showed that border furrow irrigation technology optimized the parameters of the irrigation,and significantly improved the irrigation efficiency and irrigation uniformity.