不同牧草品种用作绿肥对盐碱地土壤养分的影响

通过对国内外9个不同牧草品种在盐碱地进行单播及2个混播处理,测定孕穗期(孕蕾期)和压青后不同牧草品种对土壤有机质、全氮、全磷、全钾、速效氮(碱解氮)、速效钾以及pH值的影响,进而评价遴选适合在盐碱地栽培种植的牧草品种作为备选绿肥。试验结果表明:不同牧草品种均可有效提高土壤有机质含量,效果由高到低依次为甜燕2号+草原224饲用豌豆、新疆毛苕子、当地白豌豆和Savane毛苕子,分别比对照组提高了4.76倍、4.00倍、3.44倍和3.14倍;不同绿肥对土壤N、P、K的提高程度不同,以Nacre箭筈豌豆、草原224饲用豌豆、当地黑豌豆和当地白豌豆表现较好,都显著高于对照(P<0.05);速效氮和速效钾含量在绿肥处理后都有不同程度的提高,其中新疆毛苕子、当地白豌豆和Savane毛苕子等都表现较好。不同牧草在压青后对土壤pH值有不同的影响,但Savane毛苕子、新疆毛苕子和当地白豌豆压青后均有显著降低(P<0.05)。综合各项指标来看,新疆毛苕子、当地白豌豆和Savane毛苕子比较适合作为在盐碱地种植的绿肥作物。

Effects of Different Forage Varieties Used as Green Manure on Saline-alkali Soil Nutrients

In this study, a total of 9 different forage varieties collected from domestic and foreign countries were planted in saline-alkali soils with single-sowing and two mixed sowing treatments. To select the suitable green manure varieties for cultivation in saline-alkali land, soil organic matter, total nitrogen, total phosphorus, total potassium, available nitrogen （alkali nitrogen）, available potassium and soil pH value were determined in two different period （booting stage and green manuring period） after planting. The results showed that different forages effectively increased the soil organic matter contents, and the groups of Avena sativa L. cv. Tianyan 2 + Pisum sativum L. cv. Caoyuan 224, Vicia villosa Roth. cv. Xinjiang, Pisum sativum L. cv. Dangdibai, and Vicia villosa Roth. cv. Savane were more effective, which were 4.76, 4.00, 3.44 and 3.14 times higher than that of the control group. In addition, different forages had different degrees of improvement in soil N, P and K, and Vicia sativa L. cv. Nacre, Pisum sativum L. cv. Caoyuan 224, Pisum sativum L. cv. Dangdihei and Pisum sativum L. cv. Dangdibai performed better, all of which were significantly higher than that of the control （P<0.05）group. The contents of available nitrogen and available potassium were increased after different green manure treatment, among which Vicia villosa Roth. cv. Xinjiang, Pisum sativum L. cv. Dangdibai and Vicia villosa Roth. cv. Savane performed better. Different forages had different effects on soil pH value after green manuring treatment, but the treatments of Vicia villosa Roth. cv. Savane, Vicia villosa Roth. cv. Xinjiang and Pisum sativum L. cv. Dangdibai showed significantly reduction （P<0.05）. In conclusion, Vicia villosa Roth. cv. Xinjiang, Pisum sativum L. cv. Dangdibai and Vicia villosa Roth. cv. Savane are more suitable as green manure crops grown on saline-alkali land.