| 1. |
- Lobo, José, et al.
(author)
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A convergence research perspective on graduate education for sustainable urban systems science
- 2021
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In: npj Urban Sustainability. - : Springer. - 2661-8001. ; 1
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Journal article (peer-reviewed)abstract
- Sustainable urban systems (SUS) science is a new science integrating work across established and emerging disciplines, using diverse methods, and addressing issues at local, regional, national, and global scales. Advancing SUS requires the next generation of scholars and practitioners to excel at synthesis across disciplines and possess the skills to innovate in the realms of research, policy, and stakeholder engagement. We outline key tenets of graduate education in SUS, informed by historical and global perspectives. The sketch is an invitation to discuss how graduates in SUS should be trained to engage with the challenges and opportunities presented by continuing urbanization.
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| 2. |
- Sanders, Luciana M., et al.
(author)
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Carbon accumulation in Amazonian floodplain lakes : A significant component of Amazon budgets?
- 2017
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In: Limnology and Oceanography Letters. - : Wiley. - 2378-2242. ; 2:1, s. 29-35
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Journal article (peer-reviewed)abstract
- The Amazon floodplains cover approximately 10% of the Amazon Basin and are composed of predominantly anoxic sediments that may store large amounts of carbon. Our study combines Pb-210 derived sedimentation rates from four recently analyzed sediment cores (n = 4) with previously published organic carbon (OC) burial estimates (n = 18) to provide a broad, first order estimate of carbon accumulation in Amazon floodplain lakes. The OC burial rates were 266 +/- 57 g C m(-2) yr(-1). This rate is several folds greater than those reported for lakes in arctic, boreal, temperate, and tropical regions. The large amount and spatial variation of OC burial rates in these floodplain lakes highlights the need for increased sampling efforts to better measure these potentially important components of the Amazon Basin carbon budget.
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| 3. |
- Sanders, Luciana M., et al.
(author)
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Historic carbon burial spike in an Amazon floodplain lake linked to riparian deforestation near Santarem, Brazil
- 2018
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In: Biogeosciences. - : COPERNICUS GESELLSCHAFT MBH. - 1726-4170 .- 1726-4189. ; 15:2, s. 447-455
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Journal article (peer-reviewed)abstract
- Forests along the Amazon Basin produce significant quantities of organic material, a portion of which is deposited in floodplain lakes. Deforestation in the watershed may then have potentially important effects on the carbon fluxes. In this study, a sediment core was extracted from an Amazon floodplain lake to examine the relationship between carbon burial and changing land cover and land use. Historical records from the 1930s and satellite data from the 1970s were used to calculate deforestation rates between 1930 to 1970 and 1970 to 2010 in four zones with different distances from the margins of the lake and its tributaries (100, 500, 1000 and 6000m buffers). A sediment accumulation rate of similar to 4 mmyr(-1) for the previous similar to 120 years was determined from the Pu240+239 signatures and the excess Pb-210 method. The carbon burial rates ranged between 85 and 298 gCm(-2) yr(-1), with pulses of high carbon burial in the 1950s, originating from the forest vegetation as indicated by delta C-13 and delta N-15 signatures. Our results revealed a potentially important spatial dependence of the organic carbon (OC) burial in Amazon lacustrine sediments in relation to deforestation rates in the catchment. These deforestation rates were more intense in the riparian vegetation (100m buffer) during the period 1930 to 1970 and the larger open water areas (500, 1000 and 6000m buffer) during 1970 to 2010. The continued removal of vegetation from the interior of the forest was not related to the peak of OC burial in the lake, but only the riparian deforestation which peaked during the 1950s. Therefore, this supports the conservation priority of riparian forests as an important management practice for Amazon flooded areas. Our findings suggest the importance of abrupt and temporary events in which some of the biomass released by deforestation, especially restricted to areas along open water edges, might reach the depositional environments in the floodplain of the Amazon Basin.
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| 4. |
- Sanders, Luciana M., et al.
(author)
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Pu240+239 DEPOSITIONAL SIGNATURES AS A VIABLE GEOCHRONOLOGICAL TOOL IN THE AMAZON BASIN
- 2017
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In: Geochronometria. - : DE GRUYTER OPEN LTD. - 1733-8387 .- 1897-1695. ; 44:1, s. 142-149
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Journal article (peer-reviewed)abstract
- Anthropogenic radionuclide signatures associated with nuclear testing are increasingly utilized in environmental science to explore recent sedimentation. In this study, we assess the suitability of Pu radioisotope analysis in floodplain lake environments in the Amazon Basin to form geochronologies during the 20th century. The Pu-240 + Pu-239 (Pu240+239) signatures in six sediment cores indicate sediment accumulation rates in the floodplain lakes of the major rivers; Amazon (2.3 mm year(-1)), Tapajos (10.2 and 2.4 mm year(-1)) and Madeira (3.4, 4.2 and 6.2 mm year(-1)). The results from this study show that Pu240+239 fallout activities, and the well documented (Pu-240/Pu-239) atomic ratios of the above ground nuclear tests which began in the 1950s, are sufficient and well preserved in Amazon flood-plain lake sediments to infer chronologies. Lead-210 dating analyses in the same sediment cores produced comparable sediment accumulation rates at three of the six sites. The differences between dating methods may be attributed to the different time scale these dating methods represent and/or in the solubility between Pb and Pu along the sediment column. The geochronologies derived from the Pu240+239 and Pb-210 methods outlined in this work are of interest to identify the effects of changing sediment accumulation rates during the previous century as a result of development, including deforestation, along the Amazon Basin which increased towards the middle of the 20th century. This study shows that Pu dating provides a viable alternative geochronology tool for recent sediment accumulation (previous similar to 60 years) along the Amazon Basin.
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