Effect Of Spring Maize Yield Improvement Under Film Mulching Condition And Mechanism In Drylad

The film mulching cultivation can effectively improve the efficiency of crop water and fertilizer utilization.The spatial and temporal distribution of root system was affected by changing the soil micro-environment,water,fertilizer,air and heat condition.In this study,using Xianyu 335 spring corn as the test material,we set up film mulching and bare ground for two treatments.This experiment was conducted in April 2016 to September 2016 in the Chinese Academy of Sciences Changwu Loess Plateau Agricultural Ecological Experimental Station.The soil water content,soil water storage,soil available nitrogen content in 0-200 cm soil layer,temporal and spatial distribution of root system and soil available nitrogen content were measured by detecting the soil temperature,the biomass of each growth period,The relationship between temporal and spatial distribution of maize roots and soil moisture,nutrients and temperature,and the changing regulation of maize yield and water use efficiency.The following conclusions were drawn from the study;(1)During the early growth period and harvest period of spring maize,the soil water content of double-ridge mulched cultivation was higher,and in the period of R3,the treatment of film mulching was lower.In the year with sufficient precipitation(precipitation in the 2016 growth period is 390mm),the film mulching can increase the soil water storage capacity.(2)the surface soil temperature changes violently,the lower is more stable.When the surface temperature is lower than 22.6?,the film mulching will improve the soil temperature.When the surface temperature is higher than 22.6?,the film mulching will reduce the soil temperature.(3)The film mulching has lower soil available N in the whole growth period.During the V12 period,the content of available N in the broad row(and narrow row)was higher,and the soil available N in intra-row was the highest in the later growth period.(4)In the V12 and R5 periods,the root length density of the soil surface layer(0-20cm)was relatively large with bare flat surface treatment,while in the R1 and R3 periods,the root length density of the film mulching was larger.In the period of R3,the root length density of the film mulching was larger in the deeper soil layer.In the period of V12,there are more thick root in the surface layer of 0-10 cm with the film mulching,while in the period of R3,there are more fine-root in the surface layer of 0-20 cm with film mulching.Root lengthdensity showed a radial distribution from the plant site,which was the most distributed in the plant site.Root length density is larger in the wide rows than the narrow rows.(5)The film mulching can increase yield by about 35% compared with the bare land,which is mainly by increasing the grain weight.In view of the above,film mulching can effectively improve the efficiency of water and fertilizer,effectively cut off the precipitation,increase the soil water content,ease the soil temperature fluctuation,protect the root growth space,provide a good micro-environment for root growth and development.