【摘要】 在适度放牧条件下开展了白三叶与多年生黑麦草、紫羊茅、草地早熟禾和无芒雀麦的两两豆禾混播群落的种间相容性、群落生产力和稳定性的研究。17年的研究结果表明,白三叶+紫羊茅组合的年均干物质产量502g/m2,显著高于其他组合(P<0.05),但前期以白三叶+多年生黑麦草最高(P<0.05)。在时间序列混播比例的变化上,白三叶逐渐增加,然后维持在一定的范围;多年生黑麦草第1年最高,后逐渐下降;紫羊茅和草地早熟禾变化不大,而无芒雀麦减少最快,并最终消失;白三叶+紫羊茅组合的比例动态变化最小,组分稳定,而且群落抵抗力最强,年均杂草侵入量仅为2.4 g/m2,极显著地低于其他处理(P<0.01)。参试禾本科牧草与白三叶的种间相容性为紫羊茅>多年生黑麦草≥草地早熟禾>无芒雀麦。种间相容性是混播群落长期稳定性的重要决定因素。时间梯度上的群落生产力变化趋势,白三叶+紫羊茅和白三叶+草地早熟禾呈平稳略升,而白三叶+多年生黑麦草和白三叶+无芒雀麦呈前高后低模式。对混播群落稳定性的判断存在时间尺度和空间尺度。更多还原

【Abstract】 Under moderate grazing,the interspecific compatibility,primary production and stability of mixed-communities comprising Trifolium repens plus Lolium perenne(WP),Festuca rubra(WR),Poa pratensis(WK) and Bromus inermis(WB) were studied.The 17 year results showed that: there was significantly more WP in the first four years,but that WR produced a significantly(P<0.05) higher average dry matter(DM) yield(502 g/m~2·yr) than the others.In terms of the temporal dynamic pattern of the grassland components,numbers of T.repens were low at first,increased to a larger number by the third year,then fluctuated about that level.L.perenne dominated in the first year then gradually declined.F.rubra and P.pratensis fluctuated but were relatively insignificant whereas B.inermis numbers dropped rapidly and eventually disappeared from the community.Both the components of T+F were stable,and as a consequence,resulted in the strongest resistance to weed invasion with only 2.4 g/(m~2·yr)(P<0.01) in terms of weed DM.The sequence of long-term compatibilities of companion grasses was T.repens>F.rubra>L.perenne≥P.pratensis>B.inermis.Compatibility is critical to long-term stability of mixed-pasture communities.In terms of the patterns of primary yields over the 17 year study,both WR and WK showed a relatively stable community whereas both WP and WB decreased in importance.There are both spatial and temporal scales to consider when evaluating the stability of a mixed community.更多还原