Effect Of Ground Cloth Cover On Soil Water Heat And Spring Maize Growth In Loess Hilly And Gully Region

As water resources are scarce in the loess hills and ravines,it is significant to explore the dual-monopoly cover film-side planting technology for the efficient use of water resources and the development of dry farming.In this paper,we selected typical experimental sites in the loess hilly gully area,laid out three treatments of plastic membrane-geotextile cloth mulching on the ridge(MB),geotextile cloth mulching on the ridge(DB),bare soil ridge(CK),and carried out research on soil water heat and spring maize growth with duopoly mulching.The following main conclusions were achieved:(1)The mulching treatment could significantly increase soil moisture from 0 to 30 cm,and there were significant differences in soil moisture between treatments(P<0.05),and soil moisture under MB treatment conditions was significantly higher than DB and CK treatments,and soil moisture changes throughout the reproductive period showed a trend of first decreasing and then increasing,with maximum water consumption during the filling period;The daily dynamic variation of soil moisture decreases with increasing depth,and overall the daily dynamic variation is more pronounced in summer,followed by spring and the least in autumn;The daily average value of soil moisture in 15 cm soil layer of MB treatment was the highest in all seasons,followed by 30 cm and the lowest in 5 cm.The daily average value of soil moisture in 5,15,and 30 cm underground of MB treatment increased by 13.4%,32.1%,and 34.5%,respectively,compared with CK throughout the monitoring period.This shows that the MB treatment can make the water penetrate the deeper soil layer better and has a good effect on rainwater collection and moisture retention.(2)Soil temperature varied in a"sinusoidal"curve throughout the maize reproductive period,and the variation of soil temperature in different treatments at the same depth was close to each other without significant difference(P<0.05),and the variation of soil temperature decreased with increasing depth,with the shortest lag time in MB treatment and the longest lag time in CK treatment;The mulching treatments(MB,DB)showed good thermal insulation effect throughout the growth stage,and the effective soil temperature in0-30 cm from seedling to maturity showed a trend of increasing,then decreasing and then increasing again,and the effective soil temperature in 0-30 cm in MB treatment increased the most in the spike stage(plucking to stalking),and the least in CK treatment,and the opposite in the flowering stage(stalking to maturity)and the spike stage.(3)The overall increase in soil moisture under the influence of typical rainfall showed MB>DB>CK,and the depth of influence gradually deepened with the increase in rainfall.The small rainfall(LR)and medium rainfall(MR)events had a greater influence on the subsurface 5 and 15 cm soil moisture,and the 30 cm soil moisture fluctuated after the heavy rainfall(HR)event,and the S event caused the 5 and 15 cm soil moisture to basically reach saturation,and the 30 cm soil moisture showed a significant increase.There are certain fluctuations in soil temperature in each layer under the influence of rainfall,but it is mainly influenced by the air temperature obviously,with the largest variation of the soil temperature at 5cm underground and the smallest influence on soil temperature at 30cm.With the increase in rainfall,the larger the decrease in air temperature,the larger the decrease in soil temperature in each layer,and the longer the duration of cooling.(4)The mulching treatment as a whole increased the agronomic traits of spring maize plant height,ear length,ear thickness,and stalk thickness,the DB treatment increased the protein content and oil content and decreased the starch content of spring maize,and the MB treatment decreased the oil content of spring maize;the mulching treatments(MB and DB)had good water saving and yield increase effects relative to CK,with the average water-saving rate of 11.35%and 5.57%for MB and DB in two years and average yield increases of 25.53%and 17.18%;In the long term,the mulching treatment had better ecological and economic benefits,with the highest average yield-to-input ratio for the MB treatment,followed by DB and the lowest for CK,and the two-year average net income increased by2416 RMB/hm~2 and 1109 RMB/hm~2,respectively,compared with CK.