| Based on the agroforestry system positioning experiment research of Liaoning modern agricultural park "chapter ancient efficient modern ecological agriculture demonstration zone" for years, the article carried out the research of yield, land productivity, crop response, water use efficiency, water productivity, water distribution, model building and validation in apricot and peanuts, millet, sweet potato intercropping system. The purpose is to provide the theoretical reference and technical support on increase production mechanism, water resources efficient utilization and agriculture sustainable development in northeast sandstorm semi-arid region agroforestry system different interplanting mode. The conclusion is as follows:(1) Agroforestry system can improve land productivity. The apricot and millet intercropping's land equivalent ratio (LER) is the largest, which due to the enhance of system light energy utilization system.The intercropping crop output and monoculture crop output reaches a significant level, but intercropping apricot output and monoculture apricot output has not a significant difference. In the intercropping apricot and peanut, millet or sweet potato, apricot is the dominant crop and production is not affected, three kinds crops is disadvantage crop, intercropping obvious effect on crop yield. The reduced production of millet is the least, peanut is second and sweet potato is the most. It shows that the intercropping has the greatest influence on sweet potato, the least influence on millet. The main reason of crop yield reduction is that the boundary line is affected. The three kinds intercropping system has obvious advantages, the land equivalent ratio are all higher than 1.00. The land equivalent ratio of apricot and millet intercropping amplitude range is 1.35?1.52 in 3 years, with a mean of 1.43, the obvious advantages in the intercropping modes.Through the land production capacity mechanism study, it finds that three kinds intercropping system light energy utilization efficiency are 41.27%?53.39% higher than monoculture system, which means apricot and crops intercropping can improve the utilization efficiency of light energy. Among them, apricot and millet intercropping's light energy utilization efficiency is the biggest, and are increased by 106.18%(apricot and peanut)and 33.94%(apricot and sweet potato). It shows that higher light energy utilization efficiency of apricot and millet intercropping improves the corn yield and land productivity. Using the international general accumulation of dry matter dynamic equation on crop growth and development situation is simulated, in the three kinds of intercropping system, shows the advantage in four parameters, it is also the reasons that apricot and millet intercropping has showed higher land equivalent ratio.The apricot and millet intercropping's leaf area index and SPAD value are less affected by intercropping, which provides the basis for improving energy efficiency and the land equivalent ratio(2) Agroforestry system can improve water production capacity. The apricot and millet intercropping's water equivalent ratio (WER) is the largest, which due to the less water competition.The study finds that monoculture crop water use efficiency is higher than apricot and crop intercropping, but the intercropping system's water equivalent ratio (LER) increases significantly. The three kinds of intercropping system water equivalent ratio all higher than 1, among them, apricot and peanut intercropping, apricot and millet intercropping, apricot and sweet potato intercropping reaches 1.34,1.45and 1.32. The apricot and millet intercropping has the highest water equivalent ratio, in line with land equivalent ratio performance. The apricot and millet intercropping has the lowest actual transpiration (493 mm), and monoculture sweet potato has the highest actual transpiration (528 mm). The reason may be that millet has strong drought resistance, and sweet potato has higher water consumption. From the analysis on the dynamic change of soil moisture content in different levels, different soil water advantage of intercropping patterns are apricot and millet intercropping> apricot and peanut intercropping> apricot and sweet potato intercropping. Taking advantage of Surfer software on apricot and crops intercropping growth period soil water spatial interpolation's analysis results shows that the crop early stage can meet the need of seed germination moisture, apricot and crops intercropping has not water competition, intercropping peanut 0?20 cm soil moisture content is low, it may be associated with peanut seed germination need more moisture content. Exuberant growth period of plants, and due to the blade sealing ridge, the surface evaporation is small. Although apricot and crops intercropping has a moisture competition in this stage, but due to large rainfall, competition is not obvious. Plant reproductive growth period, due to the cumulative rainfall is less, and crop storage capacity is more, leads to moisture competition obviously. To sum up, apricot and millet intercropping, apricot and peanut intercropping are water to promote the performance, apricot and sweet potato intercropping is water to compete the performance, and different levels promotion and competition between different modes.(3) FST model can simulate the agroforestry system's light intercepting rate, transpiration, soil moisture dynamic change and water stress coefficient index.Agroforestry system simulate the light water results are good based on FST model, apricot and millet intercropping system accumulated light interception quantity is higher than monoculture crop and monoculture apricot significantly, it suggests that intercropping system shows obvious advantages in light interception, and this advantage is also a main reason for the high productivity of intercropping system. The transpiration increases with plant leaves and root growth, transpiration is lower at the beginning of plant growth, the transpiration increases with the growth of leaf and root. And crop transpiration and soil moisture conditions have great relevance, in the early part of the plant growth, due to the lower leaf area index and the roots of the small, small water is demand, water supply is adequate, plant has light water stress, or not receives the effect of water stress, water stress coefficient remain at around 1, the gap between actual transpiration and evaporation potential is small. With the growth of crops, water demand increases, the precipitation is not fully meet the demand for water, soil moisture reduces quickly, the water stress of crop root system isgradually aggravate, bibulous rate is affected, transpiration reduces. In actual transpiration simulation, we can see obviously crops water stress are largely remitted after rainfall, transpiration are increasing rapidly. |
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