留茬高度对黑麦草╋白三叶草地植物补偿性生长的影响  

Compensatory growth of plant in Trifolium repens and Lolium perenne grassland under different stubble heights

作　　者：付秀琴[1] 王梅[2] 

机构地区：[1]成都农业科技职业学院,四川温江611130 [2]中国科学院成都生物研究所,四川成都610041

出　　处：《草业科学》2014年第5期927-934,共8页Pratacultural Science

基　　金：中国科学院战略先导性专项(XDA05050307);四川省科技厅项目(2011HH0011)

摘　　要：以我国南方广泛分布的黑麦草（Lolium perenne）＋白三叶（Trifolium repens）退化草地为研究对象,探讨了不同留茬高度刈割处理下草地群落、功能群和主要优势物种补偿性生长的响应模式。研究表明,刈割能提高黑麦草＋白三叶草地地上生物量,高茬（12cm,HC）和低茬（6cm,LC）刈割均能实现群落地上生物量正补偿性生长;禾草和杂类草在低茬和中茬（9cm,MC）等较大刈割强度下仍能获得较高补偿性生长;豆科牧草地上生物量在高茬及中茬等适度刈割处理下为超补偿生长模式,补偿指数G/C分别为1.20和1.23,在低茬刈割下为低补偿模式（G/C=0.98）。表明豆科牧草的补偿性生长受刈割强度影响较大,在草地管理过程中可通过合适的留茬高度来提高豆科牧草的产量。而菊科类植物在3种留茬高度下均表现为G/C〈1（介于0.31～0.48）,显示出明显的欠补偿特征。通过对不同留茬高度处理地上生物量与根系生物量分配关系分析发现,禾草类地上补偿性生长有可能是通过改变植株的生物量分配模式来实现的;杂类草和菊科植物则是由地上部分生长与根系协同生长完成;刈割对豆科植物的影响主要体现在地上部分,其根系生长具有相对独立性。群落和功能群水平的地上生物量补偿性生长最终都是由各优势物种不同响应模式来实现的。该研究结果对于解释放牧和刈割等利用方式对黑麦草＋白三叶混播草地的种群结构变化、生物量构成和再生特性影响等具有一定的参考价值。The compensatory growth of plant, which can be affected by the grazing and clipping directly, is an important character to maintain stability of grassland. Clipping is one of the main ways to use grassland in Southern China and clipping intensity （stubble height） on compensatory growth of grassland has become the core matter in grassland management to achieve the sustainable development of grassland. In this study, clipping treatments （with stubble height of 6, 9, 12 cm and unclipping） on the compensatory growth of the whole community, component functional groups and dominant species was carried out in the typical degraded grasslands dominated by Trifolium repens and Lolium perenne. At the community level, the results showed that clipping increased the aboveground biomass and over-compensatory growth was found in both high and low stubble clipping treatments, probably owning to the advantageous precipitation andtemperature in grassland of Southern China. At the functional group level, grass and forbs can achieve over-compensation even under clipping with middle and low stubble. Over-compensation of Fabaceae was only found in clipping with high and middle stubble, indicating that Fabacea species were sensitive to clipping intensity and proper clipping intensity should be adopted in grassland management to improve their production. However, clipping affected the aboveground biomass of Asteraceae negatively and the com- pensation index ranged from 0.31 to 0.48. The relationship between the aboveground and root biomass showed that the aboveground over-compensation of grass was achieved probably by sacrificing its root biomass, while the aboveground compensatory growth of forbs and Asteraceae were not related to their root biomass. The aboveground compensatory growth patterns of dominant species were mainly obtained with out reducing their root biomass. The compensatory growth patterns of community and functional groups were determined by the compensatory pattern of component species essentially. The result in

关 键 词：刈割 留茬高度 补偿性生长 黑麦草+白三叶草地 功能群 

分 类 号：S812[农业科学—草业科学]