Data from: Producer diversity enhances consumer stability in a benthic marine community

1. The diversity of many communities is changing due to local extinctions and invasions. Understanding the consequences of these changes is vital to their successful conservation, yet few studies have experimentally investigated how producer diversity affects the stability of higher trophic levels. Here we show that producer diversity, when manipulated as the only independent variable in the presence of natural top-down forces, increases the stability of consumer abundance, biomass, and diversity in a benthic marine community. 2. Using four macroalgal species (Codium fragile, Gracilaria tikvahiae, Gracilaria vermiculophylla, Gymnogongrus griffithsiae), we manipulated producer diversity (identity and richness) in a substitutive design to create seven treatments. Our treatments included four monocultures, two 3-species mixtures that differed only by including either the native or invasive Gracilaria, and the complete four species mixture. We followed the week-to-week dynamics of producer and consumer communities in each treatment concurrently for 12 weeks and quantified their temporal stability. 3. We found that higher producer diversity increased the stability of a diverse, productive consumer community. Producer biomass production did not affect consumer production or diversity, suggesting that producer diversity was solely responsible for driving the mechanisms underlying the observed multitrophic diversity–stability relationships. Taken together, our results indicate that higher producer diversity directly increased consumer diversity by increasing overyielding and decreasing the temporal variance of this response variable, and that this increased consumer diversity enhanced consumer stability via increased asynchrony among consumers. 4. Synthesis. Our results suggest that the effects of producer diversity propagate upwards to maintain diversity and productivity at higher trophic levels, and thereby enhance the overall stability of food webs.

1. 诸多群落的多样性正因本地物种灭绝与生物入侵发生改变。明晰这类变化所带来的生态效应，对群落的有效保护至关重要；然而目前鲜有研究通过实验探究初级生产者（producer）多样性如何影响更高营养级的群落稳定性。本研究表明，在存在自然下行调控力（top-down forces）的前提下，将初级生产者多样性作为唯一自变量进行操控时，可显著提升底栖海洋群落中消费者（consumer）的丰度、生物量及多样性的稳定性。
2. 本研究选取4种大型藻类（Codium fragile、Gracilaria tikvahiae、Gracilaria vermiculophylla、Gymnogongrus griffithsiae），采用替代实验设计（substitutive design）操控初级生产者的多样性（物种组成与物种丰富度），共设置7组实验处理：4个单种栽培组、2个仅差异为分别包含本地江蓠与入侵江蓠的3物种混合组，以及完整的4物种混合组。我们对各组的初级生产者与消费者群落进行了连续12周的每周动态监测，并量化了二者的时间稳定性。
3. 研究结果显示，更高的初级生产者多样性可提升结构多样、生产力旺盛的消费者群落的稳定性。初级生产者的生物量产出并未对消费者的生产力或多样性产生影响，这表明初级生产者多样性是驱动观测到的多营养级多样性-稳定性关系背后机制的唯一因素。综合来看，本研究结果表明：更高的初级生产者多样性可通过提升超产效应（overyielding）并降低该响应变量的时间方差，直接提升消费者多样性；而消费者多样性的提升则通过增强消费者类群间的异步性，强化了消费者群落的稳定性。
4. 综合分析。本研究结果表明，初级生产者多样性所带来的生态效应可沿食物链向上传递，以维持更高营养级的群落多样性与生产力，进而提升食物网的整体稳定性。