沼液施用对石灰性土壤紫花苜蓿品质影响评价

Evaluation of Effect of Biogas Slurry Application on Quality of Alfalfain Calcareous Soil

为探究沼液施用比例对石灰性土壤紫花苜蓿(Medicago sativa)品质的影响,以紫花苜蓿5010为供试材料,共设置不施肥(处理1)、常规施氮量(处理2)、氮质量分数为20%常规施氮量的沼液+80%常规施氮量(处理3)、氮质量分数为50%常规施氮量的沼液+50%常规施氮量(处理4)、氮质量分数为常规施氮量的沼液(处理5)、氮质量分数为常规施氮量2倍的沼液(处理6)等6个处理,对不同施肥处理紫花苜蓿品质指标开展分析。结果表明:相较于单施化肥,第1茬酸性洗涤纤维(ADF)、粗纤维(CF)、中性洗涤纤维(NDF)和钙(Ca),第2茬粗蛋白(CP)、Ca和糖(Sugar),第3茬CP和第5茬CP、CF质量分数在各沼液处理时均有所增加。第1茬钾(K)、CF、ADF和Ca,第2茬CP、ADF、灰分(Ash)、Ca和钾(K),第3茬CP、CF和NDF,第4茬CP、K和第5茬CP、CF、ADF质量分数在100%沼液替代时较50%沼液替代有所下降。各品质指标间多表现为极显著正相关与极显著负相关(P<0.01)。紫花苜蓿品质相关指标第一主成分为ADF、Ca、K和Sugar。基于化肥氮50%用量的沼液和50%氮肥配合施用为影响苜蓿品质的优选施肥方式。

To explore the effect of application ratio of biogas slurry on quality of alfalfa(Medicago sativa)in calcareous soil,the alfalfa 5010 was used as test material,and a total of 6 treatments were set up:no fertilization(treatment 1),conventional nitrogen application(treatment 2),biogas slurry with 20%(mass fraction,the same below)conventional nitrogen application+80%conventional nitrogen application(treatment 3),biogas slurry with 50%conventional nitrogen application+50%conventional nitrogen application(treatment 4),biogas slurry with conventional nitrogen application(treatment 5),biogas slurry with twice the conventional nitrogen application(treatment 6),and the quality indexes of alfalfa under different fertilization treatments were analyzed.The results show that compared with chemical fertilizer alone,the mass fractions of acid detergent fiber(ADF),crude fiber(CF),neutral detergent fiber(NDF)and calcium(Ca)in the first crop,crude protein(CP),Ca,and sugar in the second crop,CP in the third crop and CP,CF in the fifth cropare increased under each biogas slurry treatment.The mass fractions of potassium(K),CF,ADF,and Ca in the first crop,CP,ADF,Ash,Ca,and K in the second crop,CP,CF,NDF in the third crop,CP,K in the fourth crop and CP,CF,ADF in the fifth crop are decreased when 100%biogas slurry was substituted compared with 50%biogas slurry.Most of the quality indexes show significant positive correlation and significant negative correlation(P<0.01).The first principal components of alfalfa quality indexesare ADF,Ca,K and Sugar.The application of 50%biogas slurry and 50%nitrogen fertilizer is the optimized fertilization pattern to affect the quality of alfalfa.