沟垄二元覆盖对旱作马铃薯耗水特征、产量及水分利用效率的影响

为探讨旱作区沟垄二元覆盖模式下土壤水分、阶段耗水特性及对马铃薯产量和水分利用效率的影响效果,于2016年在宁夏南部山区通过设置垄覆地膜,沟内分别覆盖普通地膜(DD)、秸秆(DJ)、生物降解膜(DS)、液态地膜(DY)、麻纤维地膜(DM)和沟不覆盖(DB)等6种沟垄二元覆盖模式,以传统平作为对照(CK)。结果表明,DJ处理的马铃薯整个生育期土壤蓄水量最高,明显改善了马铃薯生育期土壤水分状况。在马铃薯整个生育期0~200 cm土层土壤含水量以DJ处理最高,尤其耕层(0~40 cm)土壤含水量最为显著。各处理阶段耗水量、耗水强度、耗水模系数在马铃薯各生育阶段表现不同,总体呈生育前期较低、中期增加、后期降低的趋势。在播种-苗期阶段、块茎形成-块茎膨大期阶段以DS处理的马铃薯耗水量、耗水强度和耗水模系数最大,DJ处理最低;苗期-现蕾期阶段以DD处理的耗水量、耗水强度和耗水模系数最大,其次为DM处理,DS处理最小;现蕾期-块茎形成期阶段以DY处理的耗水量、耗水强度和耗水模系数最大,DJ处理次之,DM处理最小。沟垄二元覆盖模式能够提高马铃薯产量和水分利用效率,以DJ和DD处理的增产效果最显著,分别较CK增产47.77%、44.84%;DJ处理的水分利用效率最高(68.2 kg·hm^-2·mm^-1),较CK显著提高58.97%。综上可知,垄覆地膜沟覆秸秆种植模式可显著改善马铃薯中后期0~200 cm土层土壤水分状况,使前期耗水少,中后期耗水增多,且能显著提高产量和水分利用效率。本研究结果为宁南旱作马铃薯覆盖种植高产技术提供了科学依据。

Effect of Dual-mulching of Ridge-and-Furrow on Water Consumption Characteristics,Yield and Water Use Efficiency of Potato in Dryland Farming

In order to study the effect of dual mulching of furrow and ridge patterns in dry farming area on soil moisture, soil water consumption characteristics in different stages, potato yield and water use efficiency in dry farming areas, six kinds of dual-mulching of furrow-and-ridge patterns were conducted in the mountainous area of southern Ningxia in 2016. Ridges were mulched with plastic film, while furrows were covered with common mulching film (DD), straw mulching (DJ), biodegradable film (DS), liquid mulching film (DY), hemp fiber mulching film (DM) and furrow without mulching (DB), and traditional flat (CK) was used as control. The results showed that, the DJ treatment had the highest soil water storage capacity during the whole growth period of potato, and the soil water status during the growing period of potato was obviously improved. During the whole growth period of potato, the soil water content with DJ treatment in the 0-200 cm layer was the highest, especially for the soil moisture content in 0-40 cm layer. The water consumption, water consumption intensity and water consumption mold coefficient under the dual-mulching of furrow-and-ridge patterns were different during the growing stage of potato. The overall trend in the water consumption, water consumption intensity and water consumption mold coefficient was lower in early growth stage and increase in middle of stage but decreasing in the late stage. In the sowing~seedling and tuber formation~ expansion stage, the water consumption, water consumption intensity and water consumption modulus of potato with DS treatment reached the maximum, and the DJ treatment was the lowest. In seedling~budding stage, the DD treatment had the largest water consumption, water consumption intensity and water consumption modulus, followed by DM treatment, and the DS treatment was the lowest. In budding~tuber forming stage, water consumption, water consumption intensity and water consumption modulus with DY treatment were the highest, followed by DJ treatment, and the DM treatment was the lowest. The dual-mulching of furrow-and-ridge patterns could increase potato yield and water use efficiency, the DJ and DD treatments were the most significant in increasing production. Compared with CK, the yields of potato under DJ and DD were increased by 47.77% and 44.84%, respectively. The DJ treatment had the highest water use efficiency (68.2 kg·hm^-2·mm^-1), which was 58.97% higher than CK. It can be seen that the plastic film mulched ridges and maize straw mulched furrows can significantly improve the soil water status at 0-200 cm layer in the middle and late stages of potato, with less water consumption in the early stage and more water consumption in the middle and late stages, and significantly improve the yield and water use efficiency. This study provides scientific evidence for the high-yield mulching cultivation technology of dry-farming potato in southern Ningxia.