膜下滴灌不同灌水定额及水氮耦合对打瓜耗水规律的影响

为研究不同灌水定额和不同施氮量对北疆打瓜耗水规律的影响,2016-2017年在新疆阿勒泰地区灌溉试验站陆续开展2 a大田打瓜灌水试验,讨论连续2 a不同灌水定额及水氮互作下打瓜耗水规律。2016年试验设置5个不同的灌水定额分别为300、375、450、525、600 m~3/hm~2。2017年设置3个不同灌水定额分别为300、450、600m~3/hm~2,3个不同施氮量分别为0、138、276 kg/hm~2,共9个处理。研究结果表明:不同灌水定额和水氮互作下打瓜旬均耗水量变化规律均呈先增大后减小变化规律;耗水量、耗水强度和果实膨大期的耗水模数随着灌水定额增加而呈"增大-平缓"态势;打瓜作物系数随灌水定额增加而增大,且在0. 360～0. 431间变化,其中600 m~3/hm~2灌水定额耗水量、耗水强度和作物系数最大;合适的水氮供给量有利于打瓜耗水模数、作物系数、耗水量和耗水强度增大,作物系数在0. 317～0. 445间变化;与其他生育阶段相比,不同灌水定额和水氮互作均在果实膨大期对打瓜耗水量、耗水强度和作物系数的影响最大。研究可为理解大田打瓜的耗水特性和当地打瓜节水高效生产提供依据。

Effects of different irrigation quota and water and nitrogen coupling on water consumption of seeding-watermelon under mulch drip irrigation

In order to study the effects of different irrigation quotas and nitrogen application rates on water consumption of melon in northern Xinjiang, a 2-year field experiment of melon irrigation was carried out at Altay Irrigation Experimental Station from 2016 to 2017.In 2016, five different irrigation quotas were set at 300 m³/hm², 375 m³/hm², 450 m³/hm², 525 m³/hm² and 600 m³/hm² respectively. In 2017, three different irrigation quotas were set up to 300 m³/hm², 450 m³/hm² and 600 m³/hm² respectively. Three different nitrogen rates were 0, 138 kg/hm² and 276 kg/hm², respectively. The results showed that: Under different irrigation quotas and water-nitrogen interaction, the change law of average water consumption in ten days of watermelon-beating showed the law of first increasing and then decreasing. Water consumption, water consumption intensity and water consumption modulus during fruit expansion increased with the increase of irrigation quota. The crop coefficient increased with the increase of irrigation quota, and changed from 0.360 to 0.431, among which 600 m³/hm² irrigation quota had the largest water consumption, water consumption intensity and crop coefficient. Suitable water and nitrogen supply increased water consumption modulus, crop coefficient, water consumption and water consumption intensity, and crop coefficient varied from 0.317 to 0.445. Compared with other growth stages, different irrigation quotas and water-nitrogen interaction had the greatest impact on water consumption, water consumption intensity and crop coefficient during fruit expansion stage. The study can provide a basis for understanding the water consumption characteristics of the field and the water-saving and efficient production of local melon.