CAJ | 학술논문

禾本科与豆科牧草的混播，是人工草地建植的最主要方式之一，研究氮肥对豆禾混播草地影响对维持混播草地的持续稳定生产具有重要意义。试验在温室栽培条件下研究了3个氮肥梯度（0，75，150 kg N／hm2，记作 N0， N75，N150）对无芒雀麦单播，紫花苜蓿单播以及它们混播（分别记作 G-G，L-L，G-L）生物量的影响。研究结果表明，1）在单播时，无芒雀麦对氮肥的响应较敏感，施入氮肥显著地提高无芒雀麦的生物量（P ＜0．05），而对紫花苜蓿的生物量无显著影响（P ＞0．05）。在混播时，无芒雀麦对有效氮的竞争胜过紫花苜蓿，施氮能显著地增加混播中无芒雀麦牧草的生物量（P ＜0．05），间接地抑制了紫花苜蓿生物量的发展。2）无芒雀麦和紫花苜蓿混播的总生物量介于它们单播时生物量之间，却高于它们单播时生物量的平均值。3）无芒雀麦单株地上生物量在混播时显著高于单播（P ＜0．05）。相反，紫花苜蓿的单株地上生物量单播显著高于混播（P ＜0．05）。这说明在混播系统中，无芒雀麦混播效应表现为积极的促进作用，紫花苜蓿混播效应表现为消极的抑制作用。4）在无芒雀麦和紫花苜蓿的混播中，无芒雀麦和紫花苜蓿的生长处于动态的消长中，这种变化通过土壤无机氮的水平来调控。
화본과여두과목초적혼파，시인공초지건식적최주요방식지일，연구담비대두화혼파초지영향대유지혼파초지적지속은정생산구유중요의의。시험재온실재배조건하연구료3개담비제도（0，75，150 kg N／hm2，기작 N0， N75，N150）대무망작맥단파，자화목숙단파이급타문혼파（분별기작 G-G，L-L，G-L）생물량적영향。연구결과표명，1）재단파시，무망작맥대담비적향응교민감，시입담비현저지제고무망작맥적생물량（P ＜0．05），이대자화목숙적생물량무현저영향（P ＞0．05）。재혼파시，무망작맥대유효담적경쟁성과자화목숙，시담능현저지증가혼파중무망작맥목초적생물량（P ＜0．05），간접지억제료자화목숙생물량적발전。2）무망작맥화자화목숙혼파적총생물량개우타문단파시생물량지간，각고우타문단파시생물량적평균치。3）무망작맥단주지상생물량재혼파시현저고우단파（P ＜0．05）。상반，자화목숙적단주지상생물량단파현저고우혼파（P ＜0．05）。저설명재혼파계통중，무망작맥혼파효응표현위적겁적촉진작용，자화목숙혼파효응표현위소겁적억제작용。4）재무망작맥화자화목숙적혼파중，무망작맥화자화목숙적생장처우동태적소장중，저충변화통과토양무궤담적수평래조공。
It is essential to understand the effect of nitrogen (N)fertilizer in maintaining stable biomass produc-tion in mixed legume-grass grasslands.In this study,the effects of three N levels (0,75 and 150 kg N/ha;de-noted as N0 ,N75 and N150 )on the biomasses of smooth brome and alfalfa in mono-culture and mixed-culture were investigated in greenhouse cultivation conditions.In mono-culture,N fertilizer significantly improved smooth brome biomass but had no significant effect on alfalfa biomass.In mixed-cultures,applying N signifi-cantly improved smooth brome biomass and indirectly inhibited the growth of alfalfa.In mixed-cultures,the biomass of smooth brome and alfalfa fell between the mono-culture values but was higher on average.The bio-mass of a single plant of smooth brome was significantly higher in mixed grassland than in mono-culture.The biomass of single alfalfa plants was significantly higher in mono-culture than in mixed grasslands.The study thus suggests that in mixed grasslands nitrogen positively stimulates smooth brome and suppresses alfalfa.In mixed grasslands,the growth of smooth brome and alfalfa changed dynamically and was regulated by inorganic N levels in the soil.