Turnbull Lindsay A, Isbell Forest, Purves Drew W, Loreau Michel, Hector Andy
Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
Department of Ecology, Evolution and Behavior, University of Minnesota, Minneapolis, MN 55108, USA.
Proc Biol Sci. 2016 Dec 14;283(1844). doi: 10.1098/rspb.2016.0536.
Biodiversity experiments have generated robust empirical results supporting the hypothesis that ecosystems function better when they contain more species. Given that ecosystems provide services that are valued by humans, this inevitably suggests that the loss of species from natural ecosystems could diminish their value. This raises two important questions. First, will experimental results translate into the real world, where species are being lost at an alarming rate? And second, what are the benefits and pitfalls of such valuation exercises? We argue that the empirical results obtained in experiments are entirely consistent with well-established theories of species coexistence. We then examine the current body of work through the lens of niche theory and highlight where closer links with theory could open up opportunities for future research. We argue that niche theory predicts that diversity-functioning relationships are likely to be stronger (and require more species) in the field than in simplified experimental settings. However, we caution that while many of the biological processes that promote coexistence can also generate diversity-function relationships, there is no simple mapping between the two. This implies that valuation exercises need to proceed with care.
生物多样性实验已经产生了有力的实证结果，支持了这样一种假设，即当生态系统包含更多物种时，其功能会更好。鉴于生态系统提供了为人类所重视的服务，这不可避免地表明，自然生态系统中物种的丧失可能会降低其价值。这就引出了两个重要问题。第一，实验结果能否转化到现实世界中，而在现实世界里物种正在以惊人的速度消失？第二，这种估值活动的好处和陷阱是什么？我们认为，实验中获得的实证结果与已确立的物种共存理论完全一致。然后，我们通过生态位理论的视角审视当前的研究工作，并强调与理论建立更紧密联系可为未来研究带来机遇的方面。我们认为，生态位理论预测，与简化的实验环境相比，在野外多样性与功能的关系可能更强（且需要更多物种）。然而，我们提醒，虽然许多促进共存的生物过程也能产生多样性与功能的关系，但两者之间并没有简单的对应关系。这意味着估值活动需要谨慎进行。
