不同种类夏绿肥对设施土壤的改良效应

Effect of different kinds of summer green manure on improvement of protected soil

通过盆栽试验研究了3种夏绿肥(羊角豆、柽麻、决明)种植和翻压对设施土壤养分和盐基离子含量的影响,旨在为温室大棚夏季休闲期种植绿肥改良土壤提供科学依据。结果表明:1)种植羊角豆、决明、柽麻60 d后,与对照处理相比,羊角豆、决明、柽麻处理均显著增加了土壤的有效磷含量,增加比例分别为8.6%、13.2%、25.7%;羊角豆和决明处理显著降低了土壤电导率,降低比例分别为25.0%和33.3%,对设施土壤次生盐渍化具有显著的改良趋势。决明、柽麻处理显著降低了(K^(+)+Na^(+))/(Ca^(2+)+Mg^(2+)),降低比例分别为17.0%、35.6%,有助于土壤胶体的凝聚和土壤团粒结构的形成。2)绿肥翻压110 d后,与对照处理相比,羊角豆和决明处理电导率变化不显著,柽麻处理显著增加了电导率,增加比例为50.0%。羊角豆、决明、柽麻均显著增加了土壤的速效钾含量,增加比例分别为23.7%、5.7%、9.4%;羊角豆和决明处理显著增加了土壤全氮含量,增加比例分别为17.8%和26.0%;决明、柽麻均显著降低了(K^(+)+Na^(+))/(Ca^(2+)+Mg^(2+)),降低比例分别为24.1%、18.5%,表明3种绿肥翻压后,培肥效果显著。3)综合来看,种植绿肥有显著改良土壤次生盐渍化的趋势,而绿肥翻压后培肥效果更为显著。因此,温室大棚夏季休闲期,可通过种植生长周期短、吸附能力强的夏绿肥降低土壤的盐基离子总量,改良土壤,但不宜翻压。3种夏绿肥中,推荐决明作为设施大棚夏季休闲期改良土壤的填闲作物。

In this paper,pot experiments were carried out to study the effects of three kinds of summer green manure(Hibiscus esulentus L.,Crotalaria juncea L. and Cassia tora Linn.)on soil nutrient and base ion content in greenhouse,in order to provide a scientific basis for planting green manure to improve the soil during the summer fallow period of the greenhouse.The results showed that:1)after 60 days of planting Hibiscus esulentus L.,Cassia tora Linn. and Crotalaria juncea L.,compared with the control treatment,Hibiscus esulentus L.,Cassia tora Linn. and Crotalaria juncea L. significantly increased the available phosphorus content of soil,the increased proportion was 8.6%,13.2% and 25.7%,respectively.The treatments of Hibiscus esulentus L. and Cassia tora Linn. significantly reduced the soil electrical conductivity,and the reduction ratio was 25.0% and 33.3%,respectively,which had a significant improvement trend and effect on the secondary salinization of protected soil.Cassia tora Linn. and Crotalaria juncea L. significantly reduced(K^(+)+Na^(+))/(Ca^(2+)+Mg^(2+))by 17.0% and 35.6% respectively,which contributed to the formation of soil colloid and soil aggregate structure. 2)After 110 days of pressing the green manure,compared with the control treatment,the conductivity of Hibiscus esulentus L. and Cassia tora Linn. treatment did not change significantly,but Crotalaria juncea L. treatment increased the conductivity by 50.0%.Hibiscus esulentus L.,Cassia tora Linn. and Crotalaria juncea L. all significantly increased the content of available potassium in the soil,with an increase rate of 23.7%,5.7% and 9.4%,respectively.The treatments of Hibiscus esulentus L. and Cassia tora Linn. significantly increased the total nitrogen content of soil,with the increasing proportion of 17.8% and 26.0% respectively.Both Cassia tora Linn. and Crotalaria juncea L. significantly reduced(K^(+)+Na^(+))/(Ca^(2+)+Mg^(2+))by 24.1% and 18.5% respectively,indicating that the effect of fertilization was significant after three green fertilizers were turned over.3)On the whole,planting green manure has the trend of significantly improving the secondary salinization of soil,which is beneficial to improving the secondary salinization of soil,and the effect of green manure is more significant after turning over.There fore,in the summer fallow period of the greenhouse,the total amount of soil base ions could be reduced by planting summer green manure with short growth cycle and strong adsorption capacity,but it is not suitable to turn over.Among the three kinds of summer green manure,Cassia tora Linn. is recommended as a filling crop to improve the secondary salinization of soil during summer leisure period in greenhouse.