青海东部旱地玉米覆膜对产量及水热效应的影响

Effects of Plastic Film Mulching on Yield, Water and Heat Effect of Dry Land Maize in Eastern Qinghai

为研究地膜覆盖对旱地春玉米土壤水热效应和玉米产量的影响,对青海省海东市民和县旱地春玉米全膜覆盖栽培与传统露地栽培进行比较研究,以期为当地旱地玉米覆膜栽培的可持续性提供理论依据。研究结果表明,春玉米采用覆膜技术能显著增加耕层土壤(0~20 cm)贮水量,相比于无膜处理提高了13.9%,使耕层土壤能够在生育期保持湿润状态。覆膜处理极显著提高了玉米水分利用效率,相比于无膜处理增加了9.53 kg/(mm·hm^(2)),提高了48.1%。整个生育期,覆膜处理耕层平均土壤温度比无膜处理高4.9℃,覆膜措施的增温效果主要体现在玉米生育前期,随着生育时期的推移,覆膜处理对耕层土壤温度的增温效果逐渐减小。覆膜处理可显著改善玉米百粒重和穗粒重等经济性状,相比无膜处理增产达50.6%。地膜覆盖可以较好地改善浅层土壤水热状况,促进玉米增产。同时,覆膜栽培技术存在加剧玉米对深层土壤水分消耗的风险,随着种植年限的增加可能会对土壤水分的年际平衡产生不利的影响,故如何高效调控干旱地区覆膜栽培方式下土壤水分状况还需进一步研究。

To study the effect of plastic film mulching on soil water and heat effect and yield of dry land spring maize, this study compared the whole film mulching cultivation with traditional open field cultivation in Minhe County of Haidong, Qinghai Province, so as to provide a theoretical basis for the sustainability of plastic film mulching cultivation of local dry land maize. The results show that: the application of plastic film mulching technology to spring maize cultivation could significantly increase the soil water storage(0-20 cm),which is 13.9% higher than that of non-film treatment, so the topsoil could keep moist during the growth period. Compared with the treatment without plastic film, the water use efficiency of maize is increased by9.53 kg/(mm · hm^(2)), which is 48.1% more. During the whole growth period, the average soil temperature of plastic film mulching treatment is 4.9℃ higher than that of non-mulching treatment. The warming effect of plastic film mulching is mainly observed in the early growth stage of maize, and the warming effect of film mulching treatment on soil temperature of plough layer gradually decreases with the development period.Plastic film mulching could significantly improve the economic traits of maize, such as 100 grain weight and ear grain weight,compared with the non-film treatment, the yield is increased by 50.6%. Plastic film mulching could improve the water and heat status of shallow soil and promote the yield of maize. At the same time, the plastic film mulching cultivation technology has the risk of aggravating the consumption of deep soil water by maize, and with the increase of planting years, it might have adverse effects on the annual balance of soil water.Therefore, how to effectively regulate and control the soil water status under mulching cultivation mode in arid areas still needs further research.