全生物降解地膜对渭北台塬土壤水热和作物经济效益的影响

为研究不同地膜覆盖对渭北台塬土壤水热环境及作物经济效益的影响，以甘薯品种‘济薯26’作为试验材料，通过设置全生物降解黑色地膜(M1)、全生物降解透明地膜(M2)和普通聚乙烯透明地膜(M3) 3个处理，研究不同处理对甘薯全生育期土壤温度、土壤湿度和甘薯产后经济收益的影响。结果表明：在甘薯生长前期，M2和M3处理下土壤温度高于M1，随着甘薯生长时间增加，M3处理下土壤温度高于M1和M2处理。甘薯全生育期，M3处理下土壤温度平均值较M1和M2处理分别高0.19℃和0.51℃。覆膜处理对土壤温度和水分的影响效果随土层深度增加而逐渐减弱。甘薯全生育期，M1和M2处理下土壤水分较M3处理分别降低0.67%和2.23%。M2处理下甘薯产量、商品率和总收入最高，其投入产出比最低，经济效益最佳。综上所述，考虑到地膜覆盖栽培技术长期应用对农田生态环境和耕地土壤质量的影响，结合不同地膜覆盖对增温、保墒和投入产出比的影响，全生物降解地膜有利于农业生态系统的可持续发展，以M2处理经济效益最佳，适宜在该地区持续应用。

Influence of Fully Biodegradable Mulching Film on Soil Hydrothermal Environment and Crop Economic Benefit in the Weibei Tableland Area

The sweet potato variety ‘Jishu 26’ was used as the test material to investigate the influence of different mulching films on soil hydrothermal environment and crop economic benefit in the Weibei tableland area. The effects of different treatments on soil temperature and soil moisture during the whole growth period of sweet potato and post-harvest economic benefits were investigated by setting up three treatments, including fully biodegradable black mulching film (M1), fully biodegradable transparent mulching film (M2) and common polyethylene transparent mulching film (M3). The results showed that the soil temperature under M2 and M3 was higher than that under M1 in the early stage of sweet potato growth. The soil temperature under M3 was higher than that under M1 and M2 with the increase of sweet potato growth time. The average soil temperature under M3 was 0.19℃ and 0.51℃ higher than that under M1 and M2, respectively, during the whole growth period of sweet potato. The influence of mulching treatment on soil temperature and moisture gradually decreased with the increasing of soil depth. The soil moisture content was reduced by 0.67% and 2.23% under M1 and M2, respectively, compared with that under M3 during the whole growth period of sweet potato. The yield, commodity rate and total income of sweet potato were the highest under M2, which had the lowest input-output ratio and the best economic benefit. In summary, taking into account the influence of long-term application of mulching cultivation technology on farmland ecological environment and soil quality, and the impact of different mulching films on temperature increase, moisture retention and input-output ratio, the fully biodegradable mulching film is beneficial to the sustainable development of agroecosystem, and M2 has the best economic benefit and is suitable for sustainable application in this area.