Predicting Light Regime Controls on Primary Productivity Across CONUS River Networks
Predicting Light Regime Controls on Primary Productivity Across CONUS River Networks
复制标题
预测光照制度对美国大陆河网初级生产力的控制
DOI：
10.1029/2020gl092149
复制
发表时间：
2021
影响因子：
5.2
通讯作者：
J. Harvey
中科院分区：
文献类型：
--
作者：
P. Savoy;J. Harvey
太阳辐射是生态系统生产力的基本驱动力，但缺乏对河流初级生产者可获得的光的广泛估计。我们开发了一个模型来预测河流初级生产者的可用光量，并用它来估计美国相邻地区（CONUS）的河流初级生产量。相继计算了河岸和水柱过程，改进了作为光函数的初级产量的预测。我们计算了河流宽度与河岸树木高度的比率，并使用该指标来预测超过200万河段的河岸带或水柱过程是否最限制生产力。水柱过程限制了全国50%的河流长度和80%的地表面积的生产力，不同生态区域的差异与河岸森林覆盖有关。我们的研究结果有助于大规模预测河流和河流生态系统的生产力，以及了解跨网络控制生产力的过程。
Solar radiation is a fundamental driver of ecosystem productivity, but widespread estimates of light available for primary producers in rivers are lacking. We developed a model to predict light available for river primary producers and used it to estimate river primary production across the contiguous United States (CONUS). Successively accounting for riparian and water column processes improved predictions of primary production as a function of light. We calculated the ratio of river width to riparian tree height and used this metric to predict whether riparian zones or water column processes most limit productivity for over 2 million reaches. Water column processes limited productivity for 50% of the nation's river length and 80% of its surface area, with variations across ecoregions related to riparian forest cover. Our findings facilitate large‐scale predictions of stream and river ecosystem productivity, as well as understanding the processes controlling productivity across networks.