Predicting temperature impacts on aquatic productivity: questioning the Metabolic Theory of Ecology’s “canonical” activation energies
Predicting temperature impacts on aquatic productivity: questioning the Metabolic Theory of Ecology’s “canonical” activation energies
复制标题
预测温度对水生生产力的影响：质疑生态学代谢理论的“规范”活化能
DOI：
10.1002/lno.11105
复制
发表时间：
2018
影响因子：
4.5
通讯作者：
Montagnes D
中科院分区：
文献类型：
--
作者：
Wang Q;Lyu Z;Omar S;Cornell S;Yang Z;Montagnes D
微藻占全球初级生产量的50%左右，其中大部分被原生动物消耗。因此，确定这种营养相互作用的温度敏感性是预测气候变化影响的基础。在这里，我们对当前预测性方法的应用提出质疑。热响应通常用Arrhenius函数来描述：，其中是速率(例如，生长)，a是标度因子，Ea是活化能，k是玻耳兹曼常数，T是绝对温度。影响代谢生态学理论提出，异养生物和自养生物的Ea估计值分别为0.65 eV和0.32 eV；当应用于藻类和原生动物的特定生长率时，这一差异具有显著的预测意义。通过文献回顾和统计评估，我们发现MTE预测不适用于原生动物(n= 103)和藻类(n= 183)的分类群特异性响应，其平均值分别为0.71 EV(95%可信区间：0.69-0.74)和0.61 EV(95%可信区间：0.58-0.63)。为了获得这些，我们拟合了一系列模型，其中Ea在定义的组(例如原生动物)内是恒定的，并且幅度取决于组内的个体反应。然后，通过将MTE和我们的预测应用于一个通用的原生动物-藻类捕食-被捕食模型，我们表明：(1)“规范的”MTE值导致对生产力的数倍错误描述；(2)包含两组的一般响应(0.69 EV)应该足以满足这样的模型；以及(3)应用我们的新响应对~ 5°C的温度变化上的藻类-原生动物种群动态有实质性的影响。
Microalgae contribute ~ 50% to global primary production, most of which is consumed by protozoa. Determining the thermal‐sensitivity of this trophic interaction is, therefore, fundamental to predicting impacts of climate change. Here, we question the application of current predictive approaches. Thermal responses are commonly described by the Arrhenius function: , whereris a rate (e.g., growth),Ais a scaling factor,Eais the activation energy,kis the Boltzmann‐constant, andTis absolute temperature. The influential metabolic theory of ecology (MTE) proposes that estimates ofEafor heterotrophs and autotrophs are 0.65 eV and 0.32 eV, respectively; when applied to specific growth rate of algae and protozoa, this difference has significant predictive consequences. Through literature review and statistical evaluation, we show that the MTE predictions do not apply to taxon‐specific responses of protozoa (n= 103) or algae (n= 183), with meanEaof 0.71 eV (95% confidence interval [CI]: 0.69–0.74) and 0.61 eV (95% CI: 0.58–0.63), respectively. To obtain these, we fitted a series of models whereEawas constant within a defined group (e.g., protozoa), and the amplitudeAdepended on the individual responses within the group. Then, by applying the MTE and our predictions to a generic protozoan‐algal, predator‐prey model we show that: (1) the “canonical” MTE values lead to misrepresenting productivity by several fold; (2) a general response encompassing both groups (0.69 eV) should suffice for such models; and (3) applying our new responses has substantial effects on algal‐protozoan population dynamics over temperature shifts of ~ 5°C.