Title | Climate and human influences on global sediment transfers during the past 10,000 years |
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Author | Jenny, J -P; Carvalhais, N; Francus, P; Koirala, S; Gregory-Eaves, I; Niemann, C; Arhens, B; Baud, A; Ojala, A E K; Normandeau, A ; Zolitschka, B |
Source | IPA-IAL 2018 Joint Meeting: Unravelling the Past and Future of Lakes, abstract book; 2018 p. 4 |
Links | Online - En ligne (complete volume - volume complet, pdf, 20.7
MB)
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Image |  |
Year | 2018 |
Alt Series | Natural Resources Canada, Contribution Series 20180264 |
Publisher | Stockholm University |
Meeting | IPA-IAL 2018 Joint Meeting: Unravelling the Past and Future of Lakes; Stockholm; SE; June 18-21, 2018 |
Document | book |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Canada; British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut;
Canada |
NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
Area | Northern Hemisphere |
Lat/Long WENS | -180.0000 180.0000 90.0000 0.0000 |
Subjects | environmental geology; surficial geology/geomorphology; soils science; geochronology; Agriculture; Nature and Environment; Holocene; sediment transfer; erosion; erosion rates; sedimentation rates;
surface waters; lakes; watersheds; carbon; paleoclimatology; radiometric dating; radiocarbon dating; carbon-14 dates; palynological analyses; pollen; models; Climate change; paleolimnology; Phanerozoic; Cenozoic; Quaternary |
Program | GSC Atlantic Division |
Released | 2018 06 01 |
Abstract | Accelerated soil erosion has substantial implications for land productivity, downstream lake ecosystems and biogeochemical cycles1,2. However, the lack of long-term instrumental data and the scarcity of
large-scale paleolimnological synthesis are limiting our understanding on the timing, the amplitude and the extent of soil erosion for the last millennia3. As such, the responses of soil erosion to long-term climate and land cover changes, the
effects on lakes C accumulation and the feedbacks on the climate system are still unclear today4. Here, we reconstruct sedimentation rates based on 14C chronologies for 651 lakes to assess the relative changes in lake-watersheds erosion over the
period 12,000 B.C. to A.D. 2000. Estimated soil erosion dynamics are then complemented with land cover reconstructions inferred from pollen records and with JSBACH-model climate reconstructions. We find a constant trend in our global signal of
inferred-erosion during the Holocene until trends started to increase at the continental scale beginning around 3,000 years ago, with large spatial heterogeneity between local trends. In particular, increased inferred soil erosion is recorded in
35.1% watersheds, and most of these sites show a decrease in arboreal pollen that is congruent with the erosion rate changes. Further analysis reveals that land cover change is the main driver of soil erosion in 70% of all studied watersheds. Most of
erosion variations in the last 50 years are related to agricultural intensification rather than land clearance or predominance of agricultural lands5. In contrast our synthesis strongly suggests that - at least in the Northern Hemisphere - human land
cover change has been the primary driver of accelerated erosion during the Holocene. |
Summary | (Plain Language Summary, not published) We reconstructed sedimentation rates based on 14C chronologies for 651 lakes to assess the relative changes in lake watersheds erosion over the period
12,000 B.C. to A.D. 2000. We find a constant trend in our global signal of inferred erosion during the Holocene until trends started to increase at the continental scale beginning around 3,000 years ago. |
GEOSCAN ID | 313024 |
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