Community rescue in experimental phytoplankton communities facing severe herbicide pollution

Data for:<br><br>Fugère V, Hébert MP, Costa NB, Xu CCY, Barrett RDH, Beisner BE, Bell G, Fussmann GF, Shapiro BJ, Yargeau V, Gonzalez A. (2020) Community rescue in experimental phytoplankton communities facing severe herbicide pollution.<br><br>Abstract: Community rescue occurs when ecological or evolutionary processes restore positive growth in a highly stressful environment that was lethal to the community in its ancestral form, thus averting biomass collapse in a deteriorating environment. Laboratory evidence suggests that community rescue is most likely in high-biomass communities that have previously experienced moderate doses of sublethal stress. We assessed this result under more natural conditions, in a mesocosm experiment with phytoplankton communities exposed to the ubiquitous herbicide glyphosate. We tested whether community biomass and prior herbicide exposure would facilitate community rescue after severe contamination. We found that prior exposure to glyphosate was a very strong predictor of the rescue outcome while high community biomass was not. Furthermore, although glyphosate had negative effects on diversity, it did not influence community composition significantly, suggesting a modest role for genus sorting in this rescue process. Our results expand the scope of community rescue theory to complex ecosystems and confirm that prior stress exposure is a key predictor of rescue.

数据来源：<br><br>Fugère V、Hébert MP、Costa NB、Xu CCY、Barrett RDH、Beisner BE、Bell G、Fussmann GF、Shapiro BJ、Yargeau V、Gonzalez A.（2020）《面临重度除草剂污染的实验性浮游植物群落中的群落拯救》<br><br>摘要：群落拯救（community rescue）指在对祖先状态下的群落具有致死性的极端胁迫环境中，通过生态过程与进化过程恢复群落正向生长，从而避免恶化环境中生物量崩溃的现象。已有实验室证据表明，群落拯救最易发生在曾经历过中等剂量亚致死胁迫的高生物量群落中。本研究在更贴近自然的条件下，通过开展浮游植物（phytoplankton）群落暴露于广布性除草剂草甘膦（glyphosate）的中宇宙实验（mesocosm），验证前述结论——即探究群落生物量与既往除草剂暴露史能否促进重度污染后的群落拯救。研究发现，既往草甘膦暴露是群落拯救结果的极强预测因子，而高群落生物量则无此预测效力。此外，尽管草甘膦对群落多样性具有负面影响，但并未显著改变群落组成，这表明属级物种分选在本次拯救过程中仅发挥有限作用。本研究结果将群落拯救理论的适用范围拓展至复杂生态系统，并证实既往胁迫暴露是群落拯救的关键预测因子。