氮肥施用量和种植年限对苜蓿产量和品质影响的Meta分析

Meta-Analysis of Effects of Nitrogen Fertilizer Application Rate and Planting Years on Yield and Quality of Alfalfa

为探究氮肥施用量和种植年限对苜蓿(Medicago sativa L.)产量和品质的影响,确定最佳氮肥施用量和最适宜种植年限,以中国为研究区域,通过检索文献收集整理田间数据,将数据按照氮肥添加量(不施氮;0<施氮量≤50 kg/hm^(2),低氮;50<施氮量≤100 kg/hm^(2),中氮;施氮量>100 kg/hm^(2),高氮)和种植年限(1年、2年、3年和3~5年)进行分组,采用整合分析(Meta-analysis)方法系统研究氮肥施用量和种植年限对苜蓿产量和品质(粗脂肪、粗蛋白、酸性洗涤纤维和中性洗涤纤维)的影响。结果表明:随施氮量增加,苜蓿产量和品质指数提高效应呈先升高后降低趋势,中氮水平下产量和品质指数提高效应均最高;施氮显著影响苜蓿品质指标(中性洗涤纤维除外);与低氮和高氮相比,中氮下苜蓿粗蛋白含量提高效应最高、酸性洗涤纤维降低效应最高(P<0.05)。随种植年限延长,苜蓿产量提高效应呈先升高后降低趋势,种植3年苜蓿产量提高效应最高。综上所述,从区域尺度上来看,为获得高产优质的苜蓿,建议最佳氮肥施用量为50~100 kg/hm^(2),最适宜种植年限为3年。在实际生产中,应基于生产目标,结合当地气候特征、土壤特性和苜蓿品种等实际情况,确定适宜氮肥施用量和种植年限。

ed included data on nitrogen fertilizer application,planting years,yield and quality(crude fat,crude protein,acid detergent fiber and neutral detergent fiber).Site nitrogen fertilizer application rate was classified as 0 kg/hm^(2)(no nitrogen application),0>nitrogen application rate≥50 kg/hm^(2)(low nitrogen application),50>nitrogen application rate≥100 kg/hm^(2)(medium nitrogen application),>100 kg/hm^(2)(high nitrogen application).Site alfalfa planting years were classified as 1 year,2 years,3 years and 3-5 years.The results showed that as nitrogen application rate increases,the yield and quality index of alfalfa showed first increase and then decrease,with the highest per⁃formance at medium nitrogen levels;nitrogen application significantly affected the quality indicators of alfalfa(except neutral detergent fiber);compared with low and high nitrogen,alfalfa under medium nitro⁃gen showed the highest raising effect of crude protein content and the highest reduction effect of acid deter⁃gent fiber(P<0.05).As planting years increase,the raising effect of yield of alfalfa increased firstly and then decreased,with the highest performance at 3 years.Based on the forage yield and quality data exam⁃ined in this study,peak performance occurs in 50~100 kg/hm^(2) nitrogen application rate and 3 year old stands.However,in actual production,the appropriate amount of nitrogen fertilizer application and plant⁃ing years should be selected based on production goals,combined with actual conditions such as local cli⁃mate,soil conditions,and alfalfa varieties.