Effects of Plastic Mulch Film Color on Moisture-heat-salt and Water Use Efficiency of Sunflower in Saline-alkali Land

Abstract

【Objective】 Utilization of plastic-film mulching is a widespread practice in regions with limited water resources. However, the impact of mulch film color on soil thermal condition, moisture level, salinity, as well as their implications for crop growth in saline-alkali soil remains elusive. This paper aims to bridge this knowledge gap through experimental investigation. 【Method】 The field experiment was carried out a sunflower field in the Hetao Irrigation District of Inner Mongolia with three treatments: black plastic film (BM), transparent plastic film (TM); no-mulching was taken as the control (NM). 【Result】 Both BM and TM mulching films significantly increased the temperature of the 0~15 cm soil layer at the seedling and budding stages of the sunflower by 2.9~5.8 ℃and 5.3~9.0 ℃, respectively. When the soil water matric potential was close to -20 kPa, BM and TM mulching increased the soil moisture content in the 0~20 cm soil layer by 21.3% and 10.6%, respectively, over the NM. Compared to NM, BM and TM mulching reduced soil salinity in the 0~10 cm soil layer by 51.6%~81.7% and 28.9%~80.5%, respectively, over the whole growing season; they also increased the seed yield by 51.8% and 50.1%, and water use efficiency by 49.7% and 48.9%, respectively. Black film mulching affected soil moisture, salt content and crop yield slightly more than the transparent film mulching, but the differences were not significant. 【Conclusion】 Compared with NM, black and transparent film mulching both improved soil moisture in the root zone and reduced salt accumulation in the soil surface, thereby improving yield and water use efficiency of the sunflower. Black film mulching worked slightly better than transparent film mulching though no significant difference was found between them.

Keywords

• film
• saline-alkali soil
• salinity
• temperature
• sunflower