دورية أكاديمية

The role of watershed characteristics, permafrost thaw, and wildfire on dissolved organic carbon biodegradability and water chemistry in Arctic headwater streams

التفاصيل البيبلوغرافية
العنوان: The role of watershed characteristics, permafrost thaw, and wildfire on dissolved organic carbon biodegradability and water chemistry in Arctic headwater streams
المؤلفون: J. R. Larouche, B. W. Abbott, W. B. Bowden, J. B. Jones
المصدر: Biogeosciences, Vol 12, Iss 14, Pp 4221-4233 (2015)
بيانات النشر: Copernicus Publications, 2015.
سنة النشر: 2015
المجموعة: LCC:Ecology
LCC:Life
LCC:Geology
مصطلحات موضوعية: Ecology, QH540-549.5, Life, QH501-531, Geology, QE1-996.5
الوصف: In the Alaskan Arctic, rapid climate change is increasing the frequency of disturbance including wildfire and permafrost collapse. These pulse disturbances may influence the delivery of dissolved organic carbon (DOC) to aquatic ecosystems, however the magnitude of these effects compared to the natural background variability of DOC at the watershed scale is not well known. We measured DOC quantity, composition, and biodegradability from 14 river and stream reaches (watershed sizes ranging from 1.5–167 km2) some of which were impacted by permafrost collapse (thermokarst) and fire. We found that region had a significant impact on quantity and biodegradability of DOC, likely driven by landscape and watershed characteristics such as lithology, soil and vegetation type, elevation, and glacial age. However, contrary to our hypothesis, we found that streams disturbed by thermokarst and fire did not contain significantly altered labile DOC fractions compared to adjacent reference waters, potentially due to rapid ecosystem recovery after fire and thermokarst as well as the limited spatial extent of thermokarst. Overall, biodegradable DOC ranged from 4 to 46 % and contrary to patterns of DOC biodegradability in large Arctic rivers, seasonal variation in DOC biodegradability showed no clear pattern between sites, potentially related to stream geomorphology and position along the river network. While thermokarst and fire can alter DOC quantity and biodegradability at the scale of the feature, we conclude that tundra ecosystems are resilient to these types of disturbance.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1726-4170
1726-4189
Relation: http://www.biogeosciences.net/12/4221/2015/bg-12-4221-2015.pdf; https://doaj.org/toc/1726-4170; https://doaj.org/toc/1726-4189
DOI: 10.5194/bg-12-4221-2015
URL الوصول: https://doaj.org/article/822ed64da60a452e983663fad4da350e
رقم الأكسشن: edsdoj.822ed64da60a452e983663fad4da350e
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:17264170
17264189
DOI:10.5194/bg-12-4221-2015