周乾 徐利岗 汤英 刘燕茹

摘要 [目的]研究宁夏干旱风沙草原区紫花苜蓿固定喷灌水肥协同效应和水肥管理制度。[方法]以苜蓿为试验材料，通过大田试验对不同水肥组合下固定喷灌紫花苜蓿株高、土壤水分、产量及水分生产效率等指标进行综合分析。[结果]苜蓿株高随灌水量的增加而增加，现蕾期和分枝期耗水量显著大于其他生育阶段;处理T4和T10苜蓿产量和水分利用效率均较高，且均无显著差异（P>0.05）。[结论]宁夏干旱风沙草原区苜蓿固定喷灌水肥耦合灌溉制度为灌溉定额3 600 m3/hm2，灌水次数为9次;施肥量为N 75 kg/hm2、P2O5 105 kg/hm2、K2O 90 kg/hm2。

关键词 干旱风沙草原区;紫花苜蓿;固定喷灌;灌溉制度;水肥耦合

中图分类号 S275.5 文献标识码 A 文章编号 0517-6611（2021）17-0195-06

doi：10.3969/j.issn.0517-6611.2021.17.051

Key words [Objective] To study the synergistic effects and management system of water and fertilizer of alfalfa with fixed spray irrigation in arid sand savanes of Ningxia. [Method]Taking alfalfa as test materials， the plant height， soil moisture content， yield， water production efficiency and other indices of alfalfa with fixed spray irrigation under different water and fertilizer combinations were analyzed through field experiment.[Result]The plant height of alfalfa increased with the increase of water irrigation amount. Water consumption in budding stage and branching stage was significantly higher than that in other growth stages. Treatment T10 and T4 had higher yield and water use efficiency， and there was no significant difference between the two treatments.[Conclusion] The water-fertilizer coupling irrigation system of alfalfa with fixed spray irrigation in arid sand savanes of Ningxia was as follows： the irrigation quota was 3 600 m3/hm2， irrigation times was 9 times; the fertilization amount of N， P2O5 and K2O were 75， 105 and 90 kg/hm2 respectively.

Key words Arid sand savanes;Alfalfa;Fixed spray irrigation;Irrigation system;Coupling of water and fertilizer

我國是一个干旱缺水极为严重的国家，淡水资源总量虽然有2.8万亿m3，占世界水资源总量的6%，居世界第4位，但人均水资源占有量仅为世界平均水平的25%左右，是全球人均水资源最贫乏的国家之一[1]。我国水资源分布极不均匀，宁夏是我国水资源严重短缺的省区之一，当地水资源量少质差，多年平均降水量289 mm，70%的降水量集中在汛期，北部引黄灌区不足200 mm，最小的地区仅几十毫米，多年平均蒸发量为2 200 mm左右，全区水资源总量11.63 亿m3，人均占有量190 m3，只有全国平均值的1/12，水资源可利用量少且开发利用难度大。宁夏农业用水量占总用水量的85%，且农业用水水平和用水效率低于全国平均水平，农业节水将是缓解水资源供需矛盾的主要途径。水肥一体化技术是同时进行灌溉与施肥，适时并适量满足农作物对水分和养分的需求，实现水肥协同管理和高效利用的农业技术[2-3]。大……