浅埋滴灌水肥耦合对辽西半干旱区春玉米产量的影响

为揭示辽西半干旱区浅埋滴灌水肥耦合春玉米的产量效应,采用水、氮、钾三因子五水平二次回归正交设计,于2017—2018年开展了田间试验。研究以产量(Y)为因变量,以灌溉量(W)、施氮量(N)、施钾量(K)为自变量,建立二次回归模型,分析Y与W、N、K之间的耦合关系。结果表明: 浅埋滴灌水肥耦合对产量有显著影响。W、N、K单因子对Y的提高均有促进作用,影响程度为W>N>K;二因子交互作用对产量的影响呈先提高后降低的变化趋势,交互作用的大小顺序为WN>WK>NK;三因子耦合产量效应表现为丰水丰氮丰钾配合处理最高,高水高氮高钾次之,低水低氮低钾最低。利用模型寻优,得到较高产量8000～8810 kg·hm^-2的浅埋滴灌适宜水肥配比范围,即在自然降雨条件下,灌溉量43～61 mm、施氮量138～343 kg·hm^-2、施钾量79～163 kg·hm^-2。研究结果可为北方半干旱区浅埋滴灌水肥一体化种植模式的应用推广提供依据。

Effects of water-fertilizer coupling on the yield of spring maize under shallow-buried drip irrigation in semi-arid region of western Liaoning Province

To reveal the coupling effect of water and fertilizer on the yield of spring maize under shallow-buried drip irrigation in semi-arid area of western Liaoning, a field experiment was conducted with the quadratic regression orthogonal design of three factors (water, nitrogen and potassium) crossed with five levels in 2017-2018. A quadratic regression model was established with yield (Y) as the dependent variable and irrigation amount (W), nitrogen (N) and potassium (K) application amounts as independent variables to analyze the coupling relationships between Y and W, N and K, respectively. The results showed that the shallow-drip irrigation water-fertilizer coupling had significant impact on yield. The single factor of W, N and K promoted the yield, with their effects ranking as W>N>K. The effect of two-factor interaction on yield increased first and then decreased which ranked as WN>WK>NK. Considering the three-factor coupling effect on yield, the combination of abundant water, nitrogen and potassium was the highest, followed by high water, nitrogen and potassium, and low water, nitrogen and potassium the lowest. As the optimal treatments found by the model, we obtained the suitable water-fertilizer application range of shallow-buried drip irrigation with higher target yield of 8000-8810 kg·hm^-2, that was, the irrigation amount was 43-61 mm, nitrogen 138-343 kg·hm^-2 and potassium 79-163 kg·hm^-2 under the ambient natural rainfall. The results provided a referable basis for application of water-fertilizer integrated cropping pattern under shallow-buried drip irrigation in semi-arid area of northern China.