We cannot shrug off the shoulder seasons: addressing knowledge and data gaps in an Arctic headwater
We cannot shrug off the shoulder seasons: addressing knowledge and data gaps in an Arctic headwater
复制标题
DOI：
10.1088/1748-9326/ab9d3c
复制
发表时间：
2020-10-01
影响因子：
6.7
通讯作者：
Bowden, William B.
中科院分区：
文献类型：
--
作者：
Shogren, Arial J.;Zarnetske, Jay P.;Bowden, William B.
随着北极环境变化的加速，越来越需要准确量化北极生态系统全年的响应。为了评估碳和养分通量观测的时间覆盖范围，我们使用了文献综合、定量荟萃分析以及对来自记录最齐全的北极生态系统之一：阿拉斯加北部库帕鲁克河源头的新型生物地球化学数据集的探索。对 204 项同行评审研究的荟萃分析显示，库帕鲁克河生物地球化学和水文学的观测存在很大的时间差距，解冻季节早期和晚期“肩膀”（定义为融雪之前或植物衰老之后的时期）的观测结果要少得多。为了测试和说明这种偏差可能对基本生态系统水平测量（例如河流碳和养分通量）产生多大影响，我们使用高频原位水化学传感器来估算整个解冻季节库帕鲁克源头水中溶解有机碳（DOC）和硝酸盐（NO3-）的河流出口预算。通过这个新颖的数据集，我们发现 DOC 和 NO(3)(-) 的年度出口量的很大一部分（约 30%）发生在平季，即使对于这个有详细记录的北极系统，也没有很好地描述这一点。这些分析提出了一个更广泛的问题：由于对这些季节的“冷遇”，我们错过了哪些生态信息？随着气候变化改变季节性，填补平季的这一主要数据空白对于了解北极生态系统的反应至关重要。
As environmental change in the Arctic accelerates, there is a growing need to accurately quantify the response of Arctic ecosystems throughout the year. To assess the temporal coverage of observations of carbon and nutrient fluxes, we used literature synthesis, quantitative meta-analysis, and exploration of a novel biogeochemical dataset from one of the best-documented Arctic ecosystems: the headwaters of the Kuparuk River in Northern Alaska. The meta-analysis of 204 peer-reviewed studies revealed a strong temporal gap in observations of biogeochemistry and hydrology of the Kuparuk River, with substantially fewer observations from the early and late 'shoulders' of the thaw season (defined as the period before snowmelt or after plant senescence). To test and illustrate how much this bias might influence fundamental ecosystem level measurements, such as riverine carbon and nutrient fluxes, we used high-frequency,in-situwater chemistry sensors to estimate riverine export budgets across the thaw season for dissolved organic carbon (DOC) and nitrate (NO3-) in the Kuparuk headwaters. With this novel dataset, we found that a large proportion (similar to 30%) of the annual export of DOC and NO(3)(-)occurred during the shoulder seasons, which are not well characterized even for this well-documented Arctic system. These analyses raise the broader question:what ecological information are we missing by giving these seasons the 'cold shoulder'?As climate change alters seasonality, filling this major data gap in the shoulder seasons is crucial to understand the response of Arctic ecosystems.