玉米膜下滴灌对农田土壤氧化还原电位的影响

Effect of Plastic-film Mulching on Soil Redox Potential in MaizeField under Drip Irrigation

为了研究滴灌条件下覆膜对土壤通气性的影响,于东北半湿润区开展了玉米田间试验,设置不覆膜+施肥(NM)、覆膜+施肥(PFM)、不覆膜+不施肥(CNM)和覆膜+不施肥(CPFM)共4个处理,对滴灌条件下土壤氧化还原电位(Eh)进行了观测和分析。结果表明:在小时尺度下,与不覆膜相比,覆膜可提高表层(0~10 cm)土壤氧化还原电位,表现为NM>PFM,差值为2.7~10.0 mV,提高了0.5%~2.0%。在耕作层(0~30 cm)内,覆膜措施对土壤氧化还原电位的分布均无明显影响,各处理土壤氧化还原电位的变化趋势一致,均随深度的增加而增大。覆膜与不覆膜条件下土壤氧化还原电位的生育期变化规律基本一致,随着生育期的发展逐渐降低。地膜覆盖可显著提高玉米生育前期耕作层的氧化还原电位,在拔节期和抽穗期,覆膜处理的Eh均明显高于不覆膜处理,差值为59.5~122.9 mV,提高了9.7%~22.8%。

In order to explore the effect of mulching on soil aeration under drip irrigation,field experiment was carried out in the sub-humid area of Northeast China.In the experiments,four treatments,including mulched+fertilized,non-mulched+fertilized,mulched+unfertilized and non-mulched+unfertilized drip irrigation were tested.The results showed that soil redox potential in surface layer(0-10 cm)was increased by plastic film mulching with a difference of 2.7-10.0 mV(increasing by 0.5%-2.0%)compared with no plastic film mulching.Plastic film mulching had no significant effect on the distribution of soil redox potential in 0-30 cm layer,and the redox potential of each treatment increased with the increase of depth in the range of 0-30 cm.During the maize growth period,the soil under drip irrigation belonged to strong oxidizing soil with good aeration,and the redox potential of each treatment was higher than 500 mV.Plastic film mulching significantly improved soil aeration in the early growth stage,and the soil redox potential for mulching increased by 59.5-122.9 mV(9.7%-22.8%)compared with no mulching.