【摘要】 以紫花苜蓿(Medicago sativa)与无芒雀麦(Bromus inermis)、垂穗披碱草(Elymus nutans)、虉草(Phalaris arundinacea)和猫尾草(Phleum pratense)二组分间行(豆禾间行比:0∶1、1∶0、1∶1、2∶2、1∶2、2∶1)混播草地为研究对象,通过测定播种当年混播组分根系C、N、P含量,计算C∶N、C∶P和N∶P比值,探讨禾草种类和混播比例对混播组分根系C、N、P化学计量特征的影响规律。结果表明:不同禾草种类根系C、N、P含量及C∶P和N∶P差异极显著(P<0.01)。虉草根系C、N、P含量显著高于无芒雀麦、披碱草(N除外)和猫尾草(P<0.05)。混播禾草种类对苜蓿根系C含量有显著(P<0.05)影响,而对N、P含量和C∶N、C∶P和N∶P影响不显著。混播比例对禾草根系C、N含量、C∶N、C∶P、N∶P以及苜蓿C含量、C∶N、C∶P影响极显著(P<0.01),而对禾草P含量和苜蓿N、P含量、N∶P没有显著影响。当禾草种类相同时,豆禾1∶2混播禾草和苜蓿根系C含量最高,2∶2混播次之,与其他混播比例间差异显著(P<0.05)。更多还原

【Abstract】 A grassland of Medicago sativa binary mixed with Bromus inermis,Elymus nutans,Phalaris arundinacea,Phleum pratense was taken as the research object.Contents of C,N,P in roots of mixture species were measured,as well as the corresponding C∶N,C∶P,and N∶P ratios in the sowing year during the end of growing season to better understand the influence of grass species and mixed sowing ratio on the C,N,and P ecological stoicheiometry in root of plants on mixture grassland.The results showed that grass species had significant impacts on the C,N,P concentration,C∶P ratios and N∶P ratios in roots of grasses(P<0.01).C,N,P concentration in P.arundinacea was much higher than those of B.inermis,E.nutans and P.pratense(P<0.05).Grass species had significant impacts on C concentration and no significant impacts on N,P concentration and C∶N,C∶P,N∶P ratios in alfalfa roots(P<0.05).The ratios of alfalfa-grass mixture had a significant effect on the C,N,P concentration and C∶N,C∶P,N∶P ratios in grasses roots and C concentration and C∶N,C∶P ratios in alfalfa roots(P<0.01),and had no significant effect on the P concentration in roots of grasses and N,P concentration and N∶P ratios in alfalfa roots.When the grass species was the same,C contents in grass and alfalfa roots were the highest on the mixture grassland at ratio 1∶2 of alfalfa to grass,the second was on mixture grassland at ratio 2∶2 of alfalfa to grass,and the difference with the other mixing ratios was significant(P<0.05).更多还原