2024-03-29T09:24:11Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1369542020-05-18T11:43:44Zcom_10261_88com_10261_8col_10261_341
2016-09-19T10:47:25Z
urn:hdl:10261/136954
Stream drying drives microbial ammonia oxidation and first-flush nitrate export
Merbt, S.
Proia, Lorenzo
Prosser, James I.
Martí, Eugènia
Casamayor, Emilio O.
Von Schiller, D.
Semiarid ecosystems
Stream
Ammonia oxidation
Ammonia oxidizing archaea (AOA)
Ammonia oxidizing bacteria (AOB)
Dry riverbed
Intermittent flow
Nitrification
7 páginas, 3 figuras
Stream microbial communities and associated processes are influenced by environmental
fluctuations that may ultimately dictate nutrient export. Discharge fluctuations
caused by intermittent stream flow are increasing worldwide in response to global change. We
examined the impact of flow cessation and drying on in-stream
nitrogen cycling. We determined
archaeal (AOA) and bacterial ammonia oxidizer (AOB) abundance and ammonia oxidation
activity in surface and deep sediments from different sites along the Fuirosos stream
(Spain) subjected to contrasting hydrological conditions (i.e., running water, isolated pools,
and dry streambeds). AOA were more abundant than AOB, with no major changes across
hydrological conditions or sediment layers. However, ammonia oxidation activity and sediment
nitrate content increased with the degree of stream drying, especially in surface sediments.
Upscaling of our results shows that ammonia oxidation in dry streambeds can contribute considerably
(~50%) to the high nitrate export typically observed in intermittent streams during
first-flush
events following flow reconnection. Our study illustrates how the dry channels of
intermittent streams can be potential hotspots of ammonia oxidation. Consequently, shifts in
the duration, spatial extent and severity of intermittent flow can play a decisive role in shaping
nitrogen cycling and export along fluvial networks in response to global change.
2016-09-19T10:47:25Z
2016-09-19T10:47:25Z
2016
artículo
Ecology 97(9) : 2192-2198 (2016)
0012-9658
http://hdl.handle.net/10261/136954
10.1002/ecy.1486
eng
http://dx.doi.org/10.1002/ecy.1486
Sí
openAccess
Ecological Society of America