Long-term data reveal highly-variable metabolism and transitions in trophic status in a montane stream
Long-term data reveal highly-variable metabolism and transitions in trophic status in a montane stream
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长期数据揭示了山地河流中高度可变的代谢和营养状态的转变
DOI：
10.1086/708659
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发表时间：
2020
影响因子：
1.8
通讯作者：
Compton, T. Scott
中科院分区：
文献类型：
--
作者：
Summers, Betsy M.;Horn, David J.;González-Pinzón, Ricardo;Bixby, Rebecca J.;Grace, Michael R.;Sherson, Lauren R.;Crossey, Laura J.;Stone, Mark C.;Parmenter, Robert R.;Compton, T. Scott
在溪流中，总初级生产力（GPP）和生态系统呼吸（ER）（即，河流代谢）控制营养物和有机碳的运输和归宿，反之亦然。短期和当地因素在推动这些进程中的重要性在文献中是众所周知的。然而，很少有信息存在的流代谢的时间变化的程度，以及如何当地的物理化学和大尺度的气候驱动因素影响这种变化。我们使用了7年的现场数据，从一个开放的冠层源流生态系统在美国西南部的流代谢（GPP，ER，和净生态系统生产[NEP]）的季节性和年际变化的程度进行量化，并评估这些过程中的时间变化是否与融雪径流的大小。在春季，季节平均ER（p= 0.025，r2 = 0.67）和NEP（p= 0.004，r2 = 0.83）与流量（Q）的相关性比GPP（p= 0.19，r2 = 0.32）更强，这可能是因为在融雪径流量较高的年份，营养物质和有机碳的流入量增加。季节平均GPP与Q、光照、温度、浊度和电导率之间没有很强的相关性（p≥ 0.27，r2 ≤ 0.18）。我们的长期数据显示，在几年内和几年内，从自养到异养状态的意外变化。然而，这种变异性与当地的环境因素没有很强的相关性（即，Q或光合有效辐射）或全球（即，厄尔尼诺-南方涛动）尺度。先前的范例认为，由地理和景观定位（例如，光和温度制度）控制溪流的营养状态，但我们的研究结果表明，时空可变因素的复杂组合，如积雪和融化，以及它们在连接陆地和水生生态系统中的作用，可以导致大量的流内变化的自养或异养状态。
In streams, gross primary production (GPP) and ecosystem respiration (ER) (i.e., stream metabolism) control the transport and fate of nutrients and organic carbon and vice versa. The importance of short-term and local factors in driving these processes is well known in the literature. However, little information exists regarding the extent of temporal variability of stream metabolism and how both local physicochemical and broad-scale climatic drivers affect this variability. We used 7 years of field data from an open-canopy headwater stream ecosystem in the southwestern United States to quantify the extent of seasonal and inter-annual variability in stream metabolism (GPP, ER, and net ecosystem production [NEP]) and to assess if temporal variation in these processes was related to the magnitude of snowmelt runoff. In spring, seasonal mean ER (p= 0.025,r2= 0.67) and NEP (p= 0.004,r2= 0.83) were more strongly related to discharge (Q) than GPP (p= 0.19,r2= 0.32), potentially because of an increased influx of nutrients and organic carbon during years with higher snowmelt runoff. There were no strong relationships between seasonal mean GPP andQ, light, temperature, turbidity, and specific conductance (p≥ 0.27,r2≤ 0.18). Our long-term data revealed unanticipated shifts from autotrophic to heterotrophic status within and across years. However, this variability was not strongly associated with environmental factors at either local (i.e.,Qor photosynthetically-active radiation) or global (i.e., El Niño-Southern Oscillation) scales. Previous paradigms hold that local attributes dictated by geographic and landscape positioning (e.g., light and temperature regimes) control the trophic status of streams, but our findings suggest that complex combinations of spatiotemporally-variable factors, such as snow accumulation and melting, and their role in connecting terrestrial and aquatic ecosystems can lead to substantial within-stream variation in autotrophic or heterotrophic status.
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影响因子：
11.4
作者：
Jones, Timothy D.;Chappell, Nick A.;Tych, Wlodek
通讯作者：
Tych, Wlodek
影响因子：
4.8
作者：
Hotchkiss, Erin R.;Hall, Robert O., Jr.
通讯作者：
Hall, Robert O., Jr.
影响因子：
2.7
作者：
Dahm, Clifford N.;Candelaria-Ley, Roxanne I.;van Horn, David J.
通讯作者：
van Horn, David J.
探索全流代谢：空间异质性对速率估计的影响
DOI：
--
发表时间：
2017
期刊：
影响因子：
--
作者：
Adam C. Siders;D. Larson;Janine Rüegg;W. Dodds
通讯作者：
W. Dodds
全球变化对河流生态系统的影响：埃布罗河代谢的高分辨率流域研究。
影响因子：
9.8
作者：
Jonatan Val;D. Chinarro;M. R. Pino;E. Navarro
通讯作者：
E. Navarro