施肥和刈割对紫茎泽兰和黑麦草苗期竞争的研究(简报)

通过种植牧草抑制外来入侵种紫茎泽兰是一条重要的替代控制途径。为探究施肥和黑麦草刈割等管理措施对紫茎泽兰与多年生黑麦草竞争的影响,运用de Wit取代系列设计,设置不施肥与施肥2个肥力水平、黑麦草不刈割与刈割2个干扰水平,对紫茎泽兰和黑麦草苗期的相对竞争表现进行了研究,同时观察了紫茎泽兰苗期的形态特征变化。结果表明,施肥和黑麦草刈割2个因素对紫茎泽兰的相对产量(RY)有显著互作效应,但对黑麦草RY没有互作效应。施肥能提高紫茎泽兰的相对竞争力,而刈割黑麦草可以降低紫茎泽兰的竞争力;在所有管理处理下,黑麦草的竞争强度均大于紫茎泽兰。紫茎泽兰的株高、分枝数和生物量在施肥和不刈割黑麦草处理下达到最大,而在不施肥和刈割黑麦草处理下最小。建议在与本试验地类似的土壤中,不施或少施肥并增加黑麦草的刈割次数,来降低紫茎泽兰的竞争力,以提高黑麦草的替代控制效果。

Effects of fertilization and grass-cutting on competition between Lolium perenne and the invasive exotic Eupatorium adenophorum at seedling stage

One ecological restoration approach to replace the invasive alien Eupatorium adenophorum has been to uproot it and re-vegetate with competent forage grasses.This study investigated the relative competitive ability between perennial L.perenne and E.adenophorum at different nitrogen and phosphorus levels in the seedling stage.The competition regime was manipulated as full competition,above-ground competition only,and below-ground competition only.The relative competition(measured as the relative yield) of E.adenophorum decreased by half at the high and medium nitrogen levels compared with that at the low level,whereas phosphorus levels had no impact on competition.The relative competition of the L.perenne declined by half at the high nitrogen level compared with that at the medium and low levels.The above-ground relative yield of E.adenophorum increased 40%-100% more than the below-ground at all nitrogen levels,whereas it was not affected by phosphorus levels.Among the plant growth parameters,reducing nitrogen diminished above-ground biomass only of E.adenophorum,whereas reducing phosphorus decreased all growth parameters including plant height,root length,below and above-ground biomass.