Global patterns of light saturation and photoinhibition of lake primary production
Global patterns of light saturation and photoinhibition of lake primary production
复制标题
湖泊初级生产力的光饱和和光抑制的全球模式
DOI：
10.1080/iw-6.4.888
复制
发表时间：
2016
期刊：
影响因子：
3.1
通讯作者：
K. Rose
中科院分区：
文献类型：
--
作者：
P. Staehr;L. S. Brighenti;M. Honti;J. Christensen;K. Rose
摘要光照对湖泊初级生产力的影响取决于湖泊的物理环境、气象条件和化学条件。虽然人们早就认识到，外部和湖内条件之间的复杂相互作用会影响整个湖泊的全球初级生产力，但很少有研究评估不同类型湖泊的全球初级生产力每日和季节变化的不同驱动因素的重要性。在这项研究中，我们使用了一个独特的数据集，涵盖了广泛的湖泊的大小，营养负荷，浮游植物生物量，结合高频气象，溶解氧（DO），和光数据，以确定湖泊的GPP和调查的程度光限制和光抑制的GPP在多个时间尺度。采用贝叶斯建模方法将DO中的昼夜变化建模为光和温度的非线性函数，从而可以确定描述原位条件下每小时GPP速率的光依赖性的参数。在900天的分析，43%的中度到强烈的光饱和GPP在夏季中午的条件下，光抑制发生在这些天的77%。随着营养盐和浮游植物浓度的增加，GPP变得越来越光限制，条件也减少了光抑制的可能性。夏季最高的GPP率被发现在光限制，nonphotoinhibited湖泊营养盐浓度和浮游植物生物量升高，虽然在这些系统的年利率低得多。我们的研究结果表明，在湖泊生态系统中，光和营养盐的相互作用会影响GPP的大小和时间变异性。
Abstract The effect of light availability on lake gross primary production (GPP) depends on the physical setting and meteorological and chemical conditions characterizing the lake. Although it has long been recognized that complex interactions between external and in-lake conditions affect whole-lake GPP, few studies have evaluated the importance of different drivers of daily and seasonal variability in GPP for a diverse set of lake types. In this study, we used a unique dataset covering a wide spectrum of lakes in terms of size, nutrient loading, and phytoplankton biomass, combined with high-frequency meteorology, dissolved oxygen (DO), and light data to determine the GPP of the lakes and to investigate the degree of light limitation and photoinhibition of GPP over multiple time scales. A Bayesian modeling approach was employed to model diel changes in DO as a nonlinear function of light and temperature, making it possible to determine the parameters describing the light dependency of hourly GPP rates under in situ conditions. Of the 900 days analyzed, 43% had moderate to strongly light-saturated GPP during midday summer conditions, and photoinhibition occurred on 77% of these days. GPP became increasingly light-limited with increasing nutrient and phytoplankton concentrations, conditions that also reduced the likelihood of photoinhibition. The highest summer rates of GPP were found in the light-limited, nonphotoinhibited lakes with elevated nutrient concentrations and phytoplankton biomass, although annual rates were much lower in these systems. Our results show that the interaction of light and nutrients affects the magnitude and temporal variability of GPP in lake ecosystems.