摘要
为了明确施肥对混播草地产量稳定性的影响,在旱作基础上研究氮磷添加对内蒙古中西部轻度盐碱地紫花苜蓿-羊草人工混播草地群落特征的影响。结果表明:(1)氮磷添加显著提高了混播草地中紫花苜蓿和羊草的产量,2021年9月和2022年6月混播草地豆禾总产量在施肥处理下均显著高于对照(P<0.05),且均为氮磷处理下的豆禾总产量最高,分别为3.57 t/hm2和4.55 t/hm2,较对照分别提高了59.38%和85.71%。(2)氮磷添加改变了混播草地中紫花苜蓿和羊草的产量占比。2021年6月,氮添加处理下羊草产量占比为56%;磷添加处理和氮磷添加处理下苜蓿产量占比高于羊草,分别为56%和54%。苜蓿的再生速度高于羊草,使得刈割后混播草地的产量占比发生明显改变。2021年9月,苜蓿产量占比在各处理中均超过76%。2022年6月,苜蓿产量占比在各处理中均超过87%。综上所述,氮磷添加可促使苜蓿-羊草混播草地产量增加。苜蓿作为优势种主导了混播草地的生物量,决定了混播草地产量的稳定性。
A field experiment was conducted in mildly saline-alkaline areas of central and western Inner Mongolia to investigate the effects of nitrogen and phosphorus fertilization on yield stability of Medicago sativa-Leymus chinensis mixed grassland,relevant to dryland agriculture.The study aimed to elucidate how fertilization influences the plant community characteristics of the mixed grassland.The results showed that:(1)Nitrogen and phosphorus addition significantly increased the yield of both M.sativa and L.chinensis in the mixed grassland.In both September 2021 and June 2022,the total yield of M.sativa and L.chinensis in the mixed grassland under fertilization treatments was significantly higher than that in the control group(P<0.05).The highest total yield was observed under combined nitrogen and phosphorus addition,with the total yield of M.sativa and L.chinensis reaching 3.57 t/hm²and 4.55 t/hm²,respectively,representing increases of 59.38%and 85.71%compared to the control.(2)Fertilization treatments altered the relative yield contribution of M.sativa and L.chinensis.In June 2021,L.chinensis exhibited a higher yield proportion(56%)than M.sativa under nitrogen addition alone.However,under phosphorus addition and combined nitrogen and phosphorus addition,M.sativa became the dominant species,contributing 56%and 54%of the total yield,respectively.(3)The faster regrowth rate of M.sativa compared to L.chinensis resulted in a significant shift in yield proportion following harvest.By September 2021,M.sativa exceeded 76%of the total yield in all treatments,and this dominance further increased to over 87%by June 2022.In conclusion,nitrogen and phosphorus fertilization promoted yield increases in M.sativa and L.chinensis mixed grassland.Notably,M.sativa emerged as the dominant species,influencing overall biomass production and potentially contributing to yield stability in the mixed grassland.
作者
齐非
李海港
陈薇薇
李轲
刘锦昉
QI Fei;LI Haigang;CHEN Weiwei;LI Ke;LIU Jinfang(College of Grassland,Resources and Environment,Inner Mongolia Agricultural University,Hohhot 010011,China)
出处
《中国草地学报》
CSCD
北大核心
2024年第6期49-56,共8页
Chinese Journal of Grassland
基金
内蒙古农业大学引进人才科研启动项目(DC1900007057)。
关键词
人工草地
施肥
牧草产量
混播
盐碱地
Artificial grassland
Fertilization
Forage yield
Mixed sowing
Saline-alkali land
