| 摘 要： |
Eutrophication generally promotes but destabilizes grassland productivity. Under eutrophication, plants tend to de-crease biomass allocation to roots but increase aboveground allocation and light limitation, likely affecting community stability. However, it remains unclear to understand how shifting plant biomass allocation and light limitation regulate grassland stability in response to eutrophication. Here, using a 5-yr multiple nutrient addition experiment in an alpine meadow, we explored the role of changes in plant biomass allocation and light limitation on its community stability under eutrophication as well as traditionally established mechanisms (i.e., plant Shannon diversity, species asyn-chrony and grass subcommunity stability). Our results showed that nitrogen (N) addition, rather than phosphorus (P) or potassium (K) addition, significantly reduced the temporal stability of the alpine meadow. In accordance with previous studies, we found that N addition decreased plant Shannon diversity, species asynchrony and grass subcom-munity stability, further destabilizing meadow community productivity. In addition, we also found the decrease in bio-mass allocation to belowground by N addition, further weakening its community stability. Moreover, this shifts in plant biomass allocation from below-to aboveground, intensifying plant light limitation. Further, the light limitation reduced plant species asynchrony, which finally weakened its community stability. Overall, in addition to traditionally established mechanisms, this study highlights the role of plant biomass allocation shifting from belowground to above-ground in determining grassland community stability. These unseen mechanisms might improve our understanding of grassland stability in the context of ongoing eutrophication. |
在线留言
联系我们
所长信箱