暗管排水条件下有机无机肥配施对向日葵产量品质与盐碱土改良效果的影响

The Effects of Organic and Inorganic Fertilizer Application on the Sunflower Yield,Quality and Saline Alkali Soil Improvement under the Subsurface Drainage

为揭示生物措施和工程措施协同改良盐碱土的效果,明确滨海农区向日葵生产适宜暗管埋设间距和有机-无机肥配施比例,研究设计10 m(S1)、15 m(S2)和20 m(S3)3种不同暗管间距和100%有机肥(100%OF)、75%有机肥+25%无机肥(75%OF)、50%有机肥+50%无机肥(50%OF)、25%有机肥+75%无机肥(25%OF)、100%无机肥(0%OF)和不施肥(CK)6种施肥处理,观测向日葵产量、品质、氮素利用和土壤速效养分、有机质、全盐含量的响应规律。结果表明:相同暗管间距下,25%OF施肥处理增产效应最为明显,而相同施肥处理下,S2间距向日葵产量处于较高水平,不同处理以S2条件下25%OF施肥处理向日葵产量最高,达到3.82 t/hm^(2);有机肥施用比例提升有利于增加向日葵籽粒粗脂肪、油酸和亚油酸含量;施肥处理明显增加了向日葵植株氮素吸收量,S1、S2和S3间距下较CK处理分别增加了18.1%~47.2%、8.6%~40.5%和8.8%~34.5%;向日葵氮素利用效率随有机肥比例的升高呈先增加后降低趋势,其中S2-25%OF和S1-25%OF处理处于较高水平,分别达到44.2%和43.9%;土壤速效氮、速效磷和速效钾含量与有机肥施用比例呈正相关,S1-S3间距下有机肥处理速效氮、速效磷和速效钾含量较CK平均高22.0%、2.4%和26.4%。暗管间距越小、有机肥施用比例越高,耕层土壤盐分消减率越高,S1间距下100%OF处理盐分消减率达42.6%。综合产量、品质、氮肥利用效率等因素,推荐以15 m暗管间距下25%有机肥施用比例作为盐碱地向日葵生产的最优方案。

In order to reveal the synergistic effect of biological and engineering measures on improving saline-alkali soil,and to clarify the suitable buried spacing and organic-inorganic fertilizer application ratio for sunflower production in coastal agricultural areas,this paper designs three different hidden pipe spacing of 10 m(S1),15 m(S2),and 20 m(S3),as well as six fertilization treatments of 100%organic fertilizer(100%OF),75%organic fertilizer+25%inorganic fertilizer(75%OF),50%organic fertilizer+50%inorganic fertilizer(50%OF),25%organic fertilizer+75%inorganic fertilizer(25%OF),100%inorganic fertilizer(0%OF)and no fertilization(CK).The response of sunflower yield,quality,nitrogen utilization,and soil available nutrients,organic matter,and total salt content is observed.The results show that under the same distance between tubes,the 25%OF fertilization treatment has the most significant yield increase effect,while under the same fertilization treatment,the S2 spacing is at a higher level in sunflower yield.Under different treatments,the 25%of fertilization treatment has the highest sunflower yield under S2 condition,reaching 3.82 t/hm^(2).Increasing the proportion of organic fertilizer application is beneficial for increasing the content of crude fat,oleic acid,and linoleic acid in sunflower seeds.Fertilization treatment significantly increases the nitrogen uptake amount of sunflower plants,with an increase of 18.1-47.2%,8.6-40.5%,and 8.8-34.5%under S1,S2,and S3 spacing compared with CK treatment,respectively.The nitrogen utilization efficiency of sunflowers shows a trend of first increasing and then decreasing with the increase in organic fertilizer proportion,S2-25%OF and S1-25%OF treatments at a higher level,reaching 44.2%and 43.9%,respectively.The content of available nitrogen,available phosphorus,and available potassium in soil is positively correlated with the proportion of organic fertilizer application.Under S1-S3 spacing,the content of available nitrogen,available phosphorus,and available potassium in organic fertilizer treatment is on average 22.0%,2.4%,and 26.4%higher than CK.The smaller the distance between hidden pipes and the higher the proportion of organic fertilizer application will lead to the higher the salt reduction rate of the topsoil.The salt reduction rate of the 100%of treatment under S1 spacing has reached 42.6%.Considering the factors such as yield,quality,and nitrogen fertilizer utilization efficiency,this paper recommends using a 25%organic fertilizer application ratio under 15 m dark tube spacing as the optimal plan for sunflower production in saline alkali soil.