By understanding the scaling nature of production along riverine networks, our framework facilitates predictions of riverine emissions globally using widely accessible chemical and hydromorphological datasets and thus, quantifies the effect of human activity and natural processes on production.Ĭarbon emissions to the atmosphere from inland waters are globally significant and mainly occur at tropical latitudes. This analysis reveals that production is bounded between two emission potentials: the upper emission potential results from production within the benthic-hyporheic zone, and the lower emission potential reflects the production within the benthic-water column zone. We show that the primary source of emissions varies with stream and river size and shifts from the hyporheic-benthic zone in headwater streams to the benthic-water column zone in rivers. Here, we analyze emissions from streams and rivers worldwide of different sizes, morphology, land cover, biomes, and climatic conditions. Our limited understanding of the relative roles of the near-surface streambed sediment (hyporheic zone), benthic, and water column zones in controlling production precludes predictions of emissions along riverine networks. Riverine environments, such as streams and rivers, have been reported as sources of the potent greenhouse gas nitrous oxide () to the atmosphere mainly via microbially mediated denitrification. Research initiatives assessing anthropogenic perturbation of the Sabaki Of material fluxes from the Sabaki River provide base-line data for future Rivers, as well as the planned damming of the Athi River, these first estimates Recent projections for increasing dissolved nutrient export from African hippopotami) may mediate theĭelivery of C4 organic matter to the river during the dry season. Suggesting that large mammalian herbivores (e.g. Of heavily 13C-enriched POC coincided with peak concentrations of PN,Īmmonium, CH4 and low dissolved oxygen saturation, Than reported yields for the neighbouring dammed Tana River. Regardless, sediment and OC yields were all at least equivalent or greater Yield of ∼ 630 Mg km−2 yr−1 for African river basins.
Scale and is considerably less than the recently reported average sediment Sediment yield (85 Mg km−2 yr−1) is relatively low on the global Phosphorus (TPP ∼ 82 %), with > 50 % of eachįraction exported during the long wet season (March–May). (∼ 89 %), dissolved organic carbon (DOC ∼ 81 %), PN (∼ 89 %) and particulate When discharge is 80 % of the total load for TSM (∼ 86 %), POC OC poor (0.3 %) to OC rich (14.9 %), with the highest %POC occurring TSM pool indicates a wide biannual variation in suspended sediment load from The contribution of particulate organic C (POC) to the ∼ 3.8 g L−1), peak concentrations of TSM rarely coincided High total suspended matter (TSM) concentrations are reported here (up to Stable isotope values of C (δ13C) and N (δ15N). Generally poor correlation between discharge and material concentrations, and Erratic seasonal variation was typical for most parameters, with Sabaki River under pre-dam conditions, and in light of the approvedĬonstruction of the Thwake Multipurpose Dam on its upper reaches (Athi
Here, we present a 2-year biogeochemical record (October 2011–December 2013) atīiweekly sampling resolution for the lower Sabaki River, Kenya, and provideĮstimates for suspended sediment and nutrient export fluxes from the lower Subsequent flux of these nutrients to the marine and atmospheric domains. Resources, are undoubtedly modulating the flux of carbon (C), nitrogen (N)Īnd phosphorus (P) between terrestrial biomes to inland waters, and the Pressures, such as rising populations and the appropriation of land and water
Inland waters impart considerable influence on nutrient cycling and budgetĮstimates across local, regional and global scales, whilst anthropogenic
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