双目标条件下玉米水肥耦合效应分析及配施方案优化研究

[目的]探究玉米产量和水分利用率的水肥耦合效应以及求出生育期最佳水肥方案。[方法]首先利用二元二次回归分析建立了玉米产量与水分利用率的水肥耦合模型,分析水、肥二因子的耦合效应;随后建立产量和水分利用率的双目标优化模型,采用快速非支配排序遗传算法Ⅱ(NSGA-Ⅱ)对模型进行求解。[结果]玉米产量和水分利用率随着水肥二因子的增加呈先增后减趋势;灌水对玉米产量和水分利用率的影响程度大于施肥;水肥耦合对玉米产量和水分利用率有正交互作用。[结论]提出的水肥配施方案:灌水量为848.24 m3/hm2,施肥量为192.66 kg/hm2的水肥组合较优玉米产量为10 667.52 kg/hm2,水分利用率为3.11 kg/m3。

基于丹参优质高产的有机无机肥最佳配施方案研究

探究锌、钼、氮磷钾和有机肥对丹参产量以及丹酚酸和丹参酮含量的影响,找出适合四川省中江县丹参种植的最佳有机无机肥配施方案。采用4因素5水平二次正交旋转组合设计,建立各因素与目标函数的函数模型,在单因素效应、互作效应分析的基础上,应用频数选优法,得到丹参优质高产的施肥方案。低锌、低氮磷钾、高钼肥水平有利于产量提高,有机肥对丹参产量的影响不显著;低氮磷钾、高有机肥有利于丹酚酸积累,锌、钼肥对丹酚酸的积累影响不显著;低锌、低钼、高氮磷钾、高有机肥有利于丹参酮积累。不同肥料的交互作用对产量、丹酚酸、丹参酮含量的影响能力及大小不同。在置信区间内,对丹参产量、丹酚酸含量、丹参酮含量分别达到最高的组合综合取交集,得到优质高产的有机无机肥最佳配施方案。锌、钼、氮磷钾与有机肥的合理配施能够提高丹参产量和丹酚酸、丹参酮的含量,其最佳组合的范围为:锌肥41.96~48.04 kg/hm^(2);钼肥0.84~0.96 kg/hm^(2);氮肥210.49~239.51 kg/hm^(2);磷肥111.26~127.74 kg/hm^(2);钾肥140.33~159.68 kg/hm^(2);有机肥1755.90~1844.10 kg/hm^(2)。

Optimization of construction scheme and supporting technology for HJS soft rock tunnel

For a soft rock tunnel under high stress in jointed and swell soft rock （HJS）, two construction schemes pilot-tunneling enlarging excavation and step-by-step excavation were optimized using FLAC20, and the deformation effects of the two construction schemes were verified by field tests. Based on engineer- ing geological investigation and mechanical analysis of large deformations, the complex deformation mechanisms of stress expansion and structural deformation of the soft rock tunnel were confirmed, and support countermeasures from the complex deformation mechanism converted to a single type were proposed, and the support parameters were optimized by field tests. These technologies were proved by engineering practice, which produced significant technical and economic benefits.