丝茅草侵入量与高羊茅相对竞争力及对幼坪性状影响的分析

通过取代试验设计,模拟丝茅草入侵高羊茅幼坪形成的混生群落,测定丝茅草与高羊茅单株的分蘖数、根系深度、分生能力及生物量,研究两者地上、地下竞争力及对草坪性状的影响。结果表明,丝茅草侵入量对高羊茅地上、地下相对产量、相对产量总和及攻击力指数均有极显著影响(P<0.01);两物种间有拮抗作用,根系存在着对相同资源的直接竞争;丝茅草地上、地下攻击力为正,竞争优势明显;高羊茅分蘖数、根系、株高显著受入侵丝茅草的影响;草坪品质与丝茅草侵入量呈极显著负相关,与株高外的其他指数呈显著正相关。防除杂草、抑制株高、促进分蘖,增加竞争力是提高高羊茅草坪品质的基本要求与必然途径。

Effect of intrusion volume of Imperata koenigii on relative competitiveness and traits of young Festuca arundinacea turf

Imperata koenigii was artificially planted into young tall fescue (Festuca arundinacea) turf. The tillering, depth and meristematic capacity of roots, and biomass were determined. Root and shoot competitiveness of the two species and traits of young tall fescue were studied. The intrusion volume of I. koenigii had a significant effect on the relative yield of root and shoot, total relative yield, and attack index of F. arundinacea. There was an antagonism between the two species. Direct competition for the same resources existed between the roots. I. koenigii had obvious competitive advantages because of its positive attack power of roots and shoots. The invasion of I. koenigii significantly affected the tillers and height of F. arundinacea. There was a significant negative correlation between turf quality of F. arundinacea and intrusion volume of I. koenigii, and a significant positive correlation between turf quality of F. arundinacea and other indexes except plant height. Weed control, inhibition of plant height, meristem promotion and competitiveness increment were basic requirements and necessary means to improve the quality of tall fescue turf.