Inland waters and their role in the carbon cycle of Alaska

Stackpoole, S. M.; Butman, David; Clow, David W.; Verdin, Kristine L.; Gaglioti, Benjamin V.; Genet, Hélène; Striegl, Robert G.

doi:10.1002/eap.1552

Cited by 89 publications

(111 citation statements)

References 148 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In comparison to global models of DOC export (Mayorga et al, 2010) and DOC exports quantified for southeastern Alaska (D'Amore et al, 2015a(D'Amore et al, , 2016Stackpoole et al, 2017), our estimates of freshwater DOC yield from Calvert and Hecate island watersheds are in the upper range predicted for the perhumid rainforest region. When compared to watersheds of similar size, DOC yields from Calvert and Hecate island watersheds are some of the highest observed (see reviews in Hope et al, 1994;Alvarez-Cobelas et al, 2012), including DOC yields from many tropical rivers, despite the fact that tropical rivers have been shown to export very high DOC (e.g., Autuna River, Venezuela, DOC yield: 56 946 kg C km −2 yr −1 ; Castillo et al, 2004) and are often regarded as having disproportionately high carbon export compared to temperate and Arctic rivers (Aitkenhead and McDowell, 2000;Borges et al, 2015).…”

Section: Doc Export From Small Catchments To the Coastal Oceanmentioning

confidence: 88%

A global hotspot for dissolved organic carbon in hypermaritime watersheds of coastal British Columbia

et al. 2017

View full text Add to dashboard Cite

Abstract. The perhumid region of the coastal temperate rainforest (CTR) of Pacific North America is one of the wettest places on Earth and contains numerous small catchments that discharge freshwater and high concentrations of dissolved organic carbon (DOC) directly to the coastal ocean. However, empirical data on the flux and composition of DOC exported from these watersheds are scarce. We established monitoring stations at the outlets of seven catchments on Calvert and Hecate islands, British Columbia, which represent the rain-dominated hypermaritime region of the perhumid CTR. Over several years, we measured stream discharge, stream water DOC concentration, and stream water dissolved organic-matter (DOM) composition. Discharge and DOC concentrations were used to calculate DOC fluxes and yields, and DOM composition was characterized using absorbance and fluorescence spectroscopy with parallel factor analysis (PARAFAC). The areal estimate of annual DOC yield in water year 2015 was 33.3 Mg C km −2 yr −1 , with individual watersheds ranging from an average of 24.1 to 37.7 Mg C km −2 yr −1 . This represents some of the highest DOC yields to be measured at the coastal margin. We observed seasonality in the quantity and composition of exports, with the majority of DOC export occurring during the extended wet period (September-April). Stream flow from catchments reacted quickly to rain inputs, resulting in rapid export of relatively fresh, highly terrestrial-like DOM. DOC concentration and measures of DOM composition were related to stream discharge and stream temperature and correlated with watershed attributes, including the extent of lakes and wetlands, and the thickness of organic and mineral soil horizons. Our discovery of high DOC yields from these small catchments in the CTR is especially compelling as they deliver relatively fresh, highly terrestrial organic matter directly to the coastal ocean. Hypermaritime landscapes are common on the British Columbia coast, suggesting that this coastal margin may play an important role in the regional processing of carbon and in linking terrestrial carbon to marine ecosystems.

show abstract

Section: Doc Export From Small Catchments To the Coastal Oceanmentioning

confidence: 88%

A global hotspot for dissolved organic carbon in hypermaritime watersheds of coastal British Columbia

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Furthermore, because Arctic-Boreal lakes are net sources of CO 2 and CH 4 (Hastie et al, 2018), fluctuations in lake area impact freshwater trace gas emissions to the atmosphere (Bastviken et al, 2011;Raymond et al, 2013). Quantifying the subseasonal variability of Arctic-Boreal lake areas is therefore critical for improving estimates of trace gas flux (Kirschke et al, 2013;Stackpoole et al, 2017) and understanding the hydrological sensitivity of lakes to geological substrate, water balance, fluvial activity, thawing permafrost, landscape disturbance, and climatic change (Bring et al, 2016). Quantifying the subseasonal variability of Arctic-Boreal lake areas is therefore critical for improving estimates of trace gas flux (Kirschke et al, 2013;Stackpoole et al, 2017) and understanding the hydrological sensitivity of lakes to geological substrate, water balance, fluvial activity, thawing permafrost, landscape disturbance, and climatic change (Bring et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Arctic‐Boreal Lake Dynamics Revealed Using CubeSat Imagery

Cooley

Smith

Ryan

et al. 2019

Geophysical Research Letters

100

View full text Add to dashboard Cite

Fine‐scale, subseasonal fluctuations in Arctic‐Boreal surface water reflect regional water balance and modulate trace gas emissions to the atmosphere but have eluded detection using traditional satellite remote sensing. We use high‐resolution (~3–5 m), high‐frequency CubeSat sensors to measure near‐daily changes in lake surface area through an object‐based tracking method that incorporates machine learning to overcome notable limitations of CubeSat imagery. From ~76,000 images we obtain >2.2 million individual observations of changing surface areas for 85,358 lakes in Northern Canada and Alaska between 1 May and 1 October 2017. We find broad‐scale lake area declines across diverse climatic, hydrologic, and physiographic terrains. Localized exceptions reveal lowland flooding and aquatic vegetation phenology cycles. Cumulative small shoreline changes of abundant lakes on the Canadian Shield exceed total inundation variations of better‐studied lowland environments, revealing a surprisingly dynamic landscape with respect to subseasonal variations in surface water extent and trace gas emissions.

show abstract

“…Corresponding observations of composition indicate that the DOM pool of these rivers contains a high proportion of hydrophilic compounds and a low DOC : dissolved organic nitrogen (DON) ratio in winter (Striegl et al ; O'Donnell et al ), characteristics positively correlated with biolability in some studies (Wickland et al ; Kiikkilä et al ). Most estimates of biolability in high‐latitude rivers have been made during summer, but many of the climate‐induced changes to DOM availability and processing might occur outside of the growing season, including more rapid soil thaw, earlier snowmelt, and reduced ice cover (Stone et al ; Brabets and Walvoord ; Euskirchen et al ; Stackpoole et al ).…”

mentioning

confidence: 99%

Regional and intra‐annual stability of dissolved organic matter composition and biolability in high‐latitude Alaskan rivers

Mutschlecner

Guerard

Jones

et al. 2018

Limnology & Oceanography

View full text Add to dashboard Cite

Nutrient availability and molecular composition of dissolved organic matter (DOM) determine whether the carbon (C) associated with DOM is respired during decomposition or exported from stream networks. High‐latitude ecosystems are changing rapidly due to permafrost thaw, shifts in vegetation, and increasing runoff, which alter sources of DOM and nutrients to rivers. To address how changes in the composition of riverine DOM and nutrients may influence C cycling, we quantified biolability of DOM across a latitudinal gradient in Alaska and assessed temporal patterns associated with intra‐annual variation in hydrology. We measured biolability under ambient and fertilized conditions and characterized optical and chemical properties of DOM to determine the relative influence of nutrients and molecular composition of DOM on its fate in rivers. Biolability was low, comprising 4% of the DOM pool on average and 0–42% across all sites and seasons. Optical indicators of the molecular composition of the DOM pool were more constant in space and time than bulk concentrations of dissolved C and nutrients, and described a DOM pool dominated by humic‐like functional groups. Phosphorus limited biolability at freshet, but biolability was not linked to DOM composition. Strong hydrologic connection of high‐latitude rivers to a large pool of soil organic matter likely results in export of recalcitrant DOM to receiving rivers and coasts in this region, contributing to stability of the high‐latitude C cycle. However, increased inputs of phosphorus or DOM of greater biolability will likely cause increased respiration of riverine DOM and flux of CO2 to the atmosphere.

show abstract

Inland waters and their role in the carbon cycle of Alaska

Cited by 89 publications

References 148 publications

A global hotspot for dissolved organic carbon in hypermaritime watersheds of coastal British Columbia

A global hotspot for dissolved organic carbon in hypermaritime watersheds of coastal British Columbia

Arctic‐Boreal Lake Dynamics Revealed Using CubeSat Imagery

Regional and intra‐annual stability of dissolved organic matter composition and biolability in high‐latitude Alaskan rivers

Contact Info

Product

Resources

About