Abstract
Invasion by alien plants is frequently attributed to increased resource availabilities. Still, our understanding is mainly based on effect of single resource. Despite the fact that plants rely on many resources, little is known about how multiple resources affect success of alien plants. Here, with two common garden experiments, one in China and one in Germany, we tested whether nutrient and light availabilities affected the competitive outcomes between alien and native plants. We found that under low resource availabilities or with addition of only one type of resources aliens were not more competitive than natives. However, with a joint increase of nutrients and light intensity, aliens outcompeted natives. Our finding indicates that addition of multiple resources could greatly reduce the number of limiting factors (i.e. niche dimensionality), and that this favors the dominance of alien species. It also indicates that habitats experiencing multiple global changes might be more vulnerable to plant invasion.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Emails: Zhijie Zhang, zhijie.zhang{at}uni-konstanz.de Yanjie Liu, liuyanjie{at}iga.ac.cn, Angelina Hardrath, angelina.hardrath{at}uni-konstanz.de Huifei Jin, jin_hui_fei{at}163.com, Mark van Kleunen, mark.vankleunen{at}uni-konstanz.de
Data and code accessibility: Should the manuscript be accepted, the data and code of the study will be archived in Figshare and the DOI will be included at the end of the article.