陕北旱地毛叶苕子不同翻压量下腐解速率及养分变化特征  

Decomposition and nutrient release characteristics of different Vicia villosa green manure applications in uplands of northern Shaanxi

作　　者：段志龙 王晨光 马欣 王辉 DUAN Zhi-long;WANG Chen-guang;MA Xin;WANG Hui(Yan’an Institute of Agricultural Sciences,Yan’an Shaanxi 716000;Shaanxi Agricultural Technology Extension Center,Xi’an Shaanxi 710003)

机构地区：[1]延安市农业科学研究所,陕西延安716000 [2]陕西省农业技术推广中心,陕西西安710003

出　　处：《中国土壤与肥料》2022年第6期182-187,共6页Soil and Fertilizer Sciences in China

基　　金：国家绿肥产业技术体系(CARS-22);陕西省农业科技创新项目(NYKJ-2019-YA-03)。

摘　　要：采用尼龙网袋法在陕北旱地进行田间腐解试验,研究了低(30000 kg/hm^(2))、中(45000 kg/hm^(2))、高(52500 kg/hm^(2))3个翻压量下毛叶苕子的干物质腐解规律和养分释放率,为合理确定绿肥翻压量和化肥配施量提供理论依据。结果表明:随着翻压时间的推移毛叶苕子腐解率呈前期迅速增加、后期缓慢的变化趋势,至试验结束时(75 d)各处理干物质的最终腐解率为61.98%~65.32%。氮、磷、钾均在翻压后的前10 d大量释放,至试验结束时氮累积释放率为69.10%~75.23%,磷累积释放率为72.25%~78.24%,钾累积释放率达81.62%~90.02%。不同翻压量下毛叶苕子氮、磷、钾的释放率和释放速率分别可用幂函数y=ax^(b)和指数衰减模型v=v_(0)e^(-kx)进行拟合,回归分析表明,不同翻压量下各养分最易达到的释放率均随翻压量的增大而降低,随着翻压量的增加,氮养分最大释放速率呈先增加后减小的趋势,磷的最大释放速率逐渐提升,钾的最大释放速率逐渐减少。增加翻压量对毛叶苕子磷完全释放的延缓效应最大(延缓145~167 d)、氮次之(延缓31~49 d)、钾最小(延缓26~38 d)。增加翻压量不会改变毛叶苕子整体的腐解及养分释放规律,但会对养分的释放率和释放速率产生影响,在实际生产中应充分结合作物需肥特性,确定毛叶苕子合理的翻压量。To provide the theoretical basis for reasonable determination of green manure turnover rate and chemical fertilizer application rate,a study was undertaken in uplands of northern Shaanxi.The decomposition and nutrient release characteristics of Vicia villosa were tested with different application amounts.Nylon net bags were used and three treatments were set up:low rate(30000 kg/hm^(2)),medium rate(45000 kg/hm^(2))and high rate(52500 kg/hm^(2)).The results showed that in all three treatments,the V.villosa decomposed rapidly in the early stage and slowly in the late stage,and the final decomposition rate of dry matter reached 61.98%~65.32%by the end of the experiment(75 d).Nitrogen,phosphorus and potassium released rapidly in the first 10 days,and nutrient release rates reached 69.10%~75.23%,72.25%~78.24%and 81.62%~90.02%,respectively,by the end of the experiment.The release rates and speeds of nitrogen,phosphorus and potassium in the different applications fitted well with the power function formula y=ax^(b) and the exponential decay model v=v_(0)e^(-kx),respectively.Regression analysis showed that the release rates of the most readily available nutrients under different turnover rates decreased with the increase of turnover rate.With the increase of turnover rate,the maximum release rate of nitrogen nutrients increased first and then decreased,the maximum release rate of phosphorus gradually increased,and the maximum release rate of potassium gradually decreased.The delay effects of nutrient release caused by increasing application amounts were phosphorus>nitrogen>potassium,with 145~167,31~49 and 26~38 d for their full release,respectively.The general rules of decomposition and nutrient release did not change significantly with the increasing application amounts,but it affected the nutrient release rate and release speed.Therefore,the reasonable application amounts of Vicia villosa should be determined by nutrient requirements of crops.

关 键 词：毛叶苕子 腐解速率 养分释放速率 

分 类 号：S142[农业科学—肥料学]