Effects Of Different Film Mulching And Irrigation Patterns On Growth Physiology And Water And Nitrogen Leaching Of Spring Maize

Hetao Irrigation Area is an important food production base in our country.Water shortage and soil salinization are important factors restricting the sustainable development of agriculture in this area.Therefore,it is of great significance to local agricultural production to explore scientific agronomic and water-salt management measures to alleviate water resource tension and soil salinization hazards.This study took spring maize as the research object,set up different irrigation modes and film mulching types,and explored the effects of different treatments on the growth physiological indicators,soil water,salt and inorganic nitrogen of spring maize.The main conclusions are as follows:（1）Irrigation method,film mulching treatment and irrigation amount treatment significantly affected crop growth and yield.Compared with bare field treatment,PE film,reinforced film and biofilm mulching treatment significantly increased the plant height,stem diameter and aboveground dry matter mass of spring maize at seedling stage and tasseling stage.The stem diameter at the seedling stage and the tasseling and silking stage increased significantly when the irrigation amount was high and the irrigation amount was lower.Compared with ground irrigation,the average yield of drip irrigation increased by 846 kg/hm²,an increase of 6.49%.Under the treatment of ground irrigation and drip irrigation,the average yield of the mulching treatment was 8.97%and 8.87%higher than that of the bare field treatment.（2）Irrigation method,film mulching treatment and irrigation amount all significantly affected leaf gas exchange parameters.Film mulching and irrigation significantly affected the net photosynthetic rate,intercellular CO₂concentration,transpiration rate and stomatal conductance of spring maize at jointing stage.Under ground irrigation,the intercellular CO₂concentration,transpiration rate and stomatal conductance of spring maize at jointing stage were significantly increased in PE film and biofilm mulching treatment compared with bare soil;the photosynthetic rate,transpiration rate and stomatal conductance were significantly increased.Under drip irrigation,the net photosynthetic rate of spring maize at jointing stage was significantly increased in the biofilm mulching treatment compared with the bare field;the net photosynthetic rate,intercellular CO₂concentration,transpiration rate and stomatal conductance were significantly increased in the middle irrigation with lower irrigation amount.The transpiration rate and water use efficiency of spring maize in drip irrigation were higher than those in ground irrigation.（3）Irrigation methods and film mulching treatments had certain effects on soil water,salt and inorganic nitrogen content.After irrigation,the changes of water,salt and inorganic nitrogen content in drip irrigation were smaller than those in ground irrigation.The salinity,inorganic nitrogen and total nitrogen contents in the drainage ditch water samples showed an increasing trend,and the contents gradually increased with the increase of irrigation times.