植物地上竞争与地下竞争研究进展

植物地上光竞争和地下水分与营养的竞争过程十分复杂,并且与竞争机制密切相关。从地上和地下竞争理论、两种竞争过程的相互作用机制以及分离地上和地下竞争的研究方法和表达指标等几个方面综述和分析目前的研究状况,以期为国内研究者在本领域进一步展开实验提供理论依据和实验设计参考。总结了与地上、地下相对竞争强度有关的优化分配理论,地上、地下竞争随生产力梯度的变化,资源异质性对地上、地下竞争机制的影响。介绍了地上竞争和地下竞争相互作用类型以及目前提出的两种作用机制。对常用的3种分离地上、地下竞争的方法:盆分隔、间植分隔和目标植分隔法以及表达竞争强度和竞争重要性的指标和公式进行了归纳。提出未来的研究内容,认为在开展此类研究时,应考虑到实验植物的生理学特性、发育状况、立地生产力跨度范围以及竞争持续时间等方面因素,并认为发展地下竞争研究、深入探讨根系间相互作用的影响因子和过程是当前的研究热点。

A literature review on the above- and below-ground competition

Plants competes for both above-ground and below-ground resources.However,there are so many conflicting reports regarding the mechanisms of competition in both natural plant population and agricultural plant communities.In this paper,we reviewed some existing literatures dealing with above-and below-ground competitions,including their experimental methodologies as well as the various indices employed in the interpretation of the intensity of both above-and below-ground competitions.It is hoped that this review will serves as a further reference point in which researchers can consider the potential directions for future research in competition studies.Optimal allocation models and theories for both under above-and below-ground competitions,and the variations as well as the trade-off between above-and below-ground competitions,including the effect of heterogeneous resources on these two different spatially competitive environments were compared.Furthermore some of the experimental methodologies in the study of competition such as the divided pot technique,row technique and target technique were reviewed with particular emphasis being placed on their advantages and limitations.In conclusion we suggested that,the following factors viz.the physiological characteristics and developmental status of experimental plants,environmental productivity range and length of competition persistence,should be considered in future studies of competition.Researches on the below-ground competition,process of root interaction and influence are now booming.