40 research outputs found
Integrating insights from social-ecological interactions into sustainable land use change scenarios for small islands in the Western Indian Ocean
Small islands are vulnerable to the synergistic effects of climate change and anthropogenic disturbances due to the fact of their small area, geographical isolation, responsive ecologies, rapidly growing and developing populations and exposure to sea level and climate change. These changes exert pressures on ecosystem services, such as the provisioning of resources, and therefore threaten the sustainability of livelihoods. We reviewed key sustainability and livelihoods literature to bring together concepts of environmental livelihood resilience and stability across temporal and spatial scales and integrated them to produce a new conceptual framework for dynamic environmental livelihood sustainability (DESL). This framework aims to facilitate the incorporation of local community perspectives into water, energy and food nexus thinking about sustainable land use to support local livelihoods. Finally, we provide insights from this case study to evaluate the effectiveness of the DESL framework in addressing gaps in existing frameworks. We suggest this framing provides a mechanism for enhancing the agency of communities to produce more cohesive and inclusive land use management plans that can lead to enhanced environmental sustainability pathways
Anthropogenic modifications to fire regimes in the wider SerengetiâMara ecosystem
Fire is a key driver in savannah systems and widely used as a land management tool. Intensifying human land uses are leading to rapid changes in the fire regimes, with consequences for ecosystem functioning and composition. We undertake a novel analysis describing spatial patterns in the fire regime of the SerengetiâMara ecosystem, document multidecadal temporal changes and investigate the factors underlying these patterns. We used MODIS active fire and burned area products from 2001 to 2014 to identify individual fires; summarizing four characteristics for each detected fire: size, ignition date, time since last fire and radiative power. Using satellite imagery, we estimated the rate of change in the density of livestock bomas as a proxy for livestock density. We used these metrics to model drivers of variation in the four fire characteristics, as well as total number of fires and total area burned. Fires in the SerengetiâMara show high spatial variabilityâwith number of fires and ignition date mirroring mean annual precipitation. The shortâterm effect of rainfall decreases fire size and intensity but cumulative rainfall over several years leads to increased standing grass biomass and fuel loads, and, therefore, in larger and hotter fires. Our study reveals dramatic changes over time, with a reduction in total number of fires and total area burned, to the point where some areas now experience virtually no fire. We suggest that increasing livestock numbers are driving this decline, presumably by inhibiting fire spread. These temporal patterns are part of a global decline in total area burned, especially in savannahs, and we caution that ecosystem functioning may have been compromised. Land managers and policy formulators need to factor in rapid fire regime modifications to achieve management objectives and maintain the ecological function of savannah ecosystems
The ACER pollen and charcoal database: a global resource to document vegetation and fire response to abrupt climate changes during the last glacial period
Quaternary records provide an opportunity to examine the nature of the
vegetation and fire responses to rapid past climate changes comparable in
velocity and magnitude to those expected in the 21st-century. The best
documented examples of rapid climate change in the past are the warming events
associated with the DansgaardâOeschger (DâO) cycles during the last glacial
period, which were sufficiently large to have had a potential feedback through
changes in albedo and greenhouse gas emissions on climate. Previous
reconstructions of vegetation and fire changes during the DâO cycles used
independently constructed age models, making it difficult to compare the
changes between different sites and regions. Here, we present the ACER (Abrupt
Climate Changes and Environmental Responses) global database, which includes
93 pollen records from the last glacial period (73â15âŻka) with a temporal
resolution better than 1000âŻyears, 32 of which also provide charcoal records.
A harmonized and consistent chronology based on radiometric dating (14C,
234Uâ230Th, optically stimulated luminescence (OSL), 40Arâ39Ar-dated tephra
layers) has been constructed for 86 of these records, although in some cases
additional information was derived using common control points based on event
stratigraphy. The ACER database compiles metadata including geospatial and
dating information, pollen and charcoal counts, and pollen percentages of the
characteristic biomes and is archived in Microsoft AccessTM at
https://doi.org/10.1594/PANGAEA.870867
Anthropogenic modifications to fire regimes in the wider Serengeti-Mara ecosystem
Fire is a key driver in savannah systems and widely used as a land management tool. Intensifying human land uses are leading to rapid changes in the fire regimes, with consequences for ecosystem functioning and composition. We undertake a novel analysis describing spatial patterns in the fire regime of the SerengetiâMara ecosystem, document multidecadal temporal changes and investigate the factors underlying these patterns. We used MODIS active fire and burned area products from 2001 to 2014 to identify individual fires; summarizing four characteristics for each detected fire: size, ignition date, time since last fire and radiative power. Using satellite imagery, we estimated the rate of change in the density of livestock bomas as a proxy for livestock density. We used these metrics to model drivers of variation in the four fire characteristics, as well as total number of fires and total area burned. Fires in the SerengetiâMara show high spatial variabilityâwith number of fires and ignition date mirroring mean annual precipitation. The shortâterm effect of rainfall decreases fire size and intensity but cumulative rainfall over several years leads to increased standing grass biomass and fuel loads, and, therefore, in larger and hotter fires. Our study reveals dramatic changes over time, with a reduction in total number of fires and total area burned, to the point where some areas now experience virtually no fire. We suggest that increasing livestock numbers are driving this decline, presumably by inhibiting fire spread. These temporal patterns are part of a global decline in total area burned, especially in savannahs, and we caution that ecosystem functioning may have been compromised. Land managers and policy formulators need to factor in rapid fire regime modifications to achieve management objectives and maintain the ecological function of savannah ecosystems.Natural Environment Research Council, Grant/Award Number: JZG10015; Leverhulme Trust, Grant/Award Number: INâ2014â022; VetenskapsrĂ„det; Sida and Formas, Grant/Award Number: 2016â06355.http://wileyonlinelibrary.com/journal/gcbhj2019Zoology and Entomolog
pSESYNTH project: Community mobilization for a multi-disciplinary paleo database of the Global South
How to enhance paleoscientific research, collaboration and application in the Global South? The INQUA-funded multi-year pSESYNTH project envisions the first multi-disciplinary Holocene paleo database through a collaborative vision for past human-environmental systems in the Global South, and their future sustainability
pSESYNTH project: Community mobilization for a multi-disciplinary paleo database of the Global South
How to enhance paleoscientific research, collaboration and application in the Global South? The INQUA-funded multi-year pSESYNTH project envisions the first multi-disciplinary Holocene paleo database through a collaborative vision for past humanâenvironmental systems in the Global South, and their future sustainability.Fil: Kulkarni, Charuta. Independent Researcher; IndiaFil: Jara, I. A.. Universidad de TarapacĂĄ; ChileFil: Chevalier, Merari. Rheinische Friedrich-wilhelms-universitĂ€t Bonn; AlemaniaFil: Isa, A. A.. Ahmadu Bello University; NigeriaFil: Alinezhad, K.. Kiel University; AlemaniaFil: Brugger, S. O.. University of Basel; SuizaFil: Bunbury, M. M. E.. James Cook University; AustraliaFil: Cordero Oviedo, C.. University of Toronto; CanadĂĄFil: Courtney Mustaphi, C.. University of Basel; SuizaFil: EcheverrĂa Galindo, P.. Technische UniversitĂ€t Braunschweig; AlemaniaFil: Ensafi Moghaddam, T.. Research Institute of Forests and Rangelands, Agricultural Research Education and Extension; IrĂĄnFil: Ferrara, V.. Stockholm University Of The Arts (uniarts);Fil: Garcia Rodriguez, F.. Universidad de la RepĂșblica; UruguayFil: Gitau, P.. National Museums Of Kenya; KeniaFil: Hannaford, M.. Lincoln University.; Nueva ZelandaFil: Herbert, A.. The Australian National University; AustraliaFil: HernĂĄndez, A.. Universidade Da Coruña; EspañaFil: Jalali, B.. Second Institute Of Oceanography; ChinaFil: Jha, D. K.. Max Planck Institute Of Geoanthropology; AlemaniaFil: Kinyanjui, R. N.. Max Planck Institute Of Geoanthropology; AlemaniaFil: Koren, G.. University of Utrecht; PaĂses BajosFil: Mackay, H.. University of Durham; Reino UnidoFil: Mansilla, C. A.. Universidad de Magallanes; ChileFil: Margalef, O.. Universidad de Barcelona; EspañaFil: Mukhopadhyay, S.. Deccan College Post Graduate Research Institute; IndiaFil: Onafeso, O.. Olabisi Onabanjo University; NigeriaFil: Riris, P.. Bournemouth University; Reino UnidoFil: Rodriguez Abaunza, A.. Indiana University; Estados UnidosFil: RodrĂguez Zorro, P.. Universidad Nacional de Colombia; ColombiaFil: Saeidi, S.. Lab. State Office For Cultural Heritage; AlemaniaFil: Ratnayake, A. S.. Uva Wellassa University; Sri LankaFil: Seitz, Carina. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - BahĂa Blanca. Instituto Argentino de OceanografĂa. Universidad Nacional del Sur. Instituto Argentino de OceanografĂa; ArgentinaFil: Spate, M.. University Of Sydney; AustraliaFil: Vasquez Perez, Carolina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Benito, Xavier. Institut de Recerca I Tecnologia AgroalimentĂ ries.; Españ
The ACER pollen and charcoal database: a global resource to document vegetation and fire response to abrupt climate changes during the last glacial period
Quaternary records provide an opportunity to examine the nature of the vegetation and fire responses to rapid past climate changes comparable in velocity and magnitude to those expected in the 21st-century. The best documented examples of rapid climate change in the past are the warming events associated with the DansgaardâOeschger (DâO) cycles during the last glacial period, which were sufficiently large to have had a potential feedback through changes in albedo and greenhouse gas emissions on climate. Previous reconstructions of vegetation and fire changes during the DâO cycles used independently constructed age models, making it difficult to compare the changes between different sites and regions. Here, we present the ACER (Abrupt Climate Changes and Environmental Responses) global database, which includes 93 pollen records from the last glacial period (73â15âŻka) with a temporal resolution better than 1000âŻyears, 32 of which also provide charcoal records. A harmonized and consistent chronology based on radiometric dating (14C, 234Uâ230Th, optically stimulated luminescence (OSL), 40Arâ39Ar-dated tephra layers) has been constructed for 86 of these records, although in some cases additional information was derived using common control points based on event stratigraphy. The ACER database compiles metadata including geospatial and dating information, pollen and charcoal counts, and pollen percentages of the characteristic biomes and is archived in Microsoft AccessTM at https://doi.org/10.1594/PANGAEA.870867
Assessing changes in global fire regimes
PAGES, Past Global Changes, is funded by the Swiss Academy of Sciences and the Chinese Academy of Sciences and supported in kind by the University of Bern, Switzerland. Financial support was provided by the U.S. National Science Foundation award numbers 1916565, EAR-2011439, and EAR-2012123. Additional support was provided by the Utah Department of Natural Resources Watershed Restoration Initiative. SSS was supported by Brigham Young University Graduate Studies. MS was supported by National Science Centre, Poland (grant no. 2018/31/B/ST10/02498 and 2021/41/B/ST10/00060). JCA was supported by the European Unionâs Horizon 2020 research and innovation program under the Marie SkĆodowska-Curie grant agreement No 101026211. PF contributed within the framework of the FCT-funded project no. UIDB/04033/2020. SGAF acknowledges support from Trond Mohn Stiftelse (TMS) and University of Bergen for the startup grant âTMS2022STG03â. JMP participation in this research was supported by the Forest Research Centre, a research unit funded by Fundação para a CiĂȘncia e a Tecnologia I.P. (FCT), Portugal (UIDB/00239/2020). A.-LD acknowledge PAGES, PICS CNRS 06484 project, CNRS-INSU, RĂ©gion Nouvelle-Aquitaine, University of Bordeaux DRI and INQUA for workshop support.Background The global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. Results Respondents indicated some direct human influence on wildfire since at leastâ~â12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. Conclusion The influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.Peer reviewe
Charcoal Whirlwinds and Post-Fire Observations in Serengeti National Park Savannahs
Whirlwinds and visible dust devils occur over semi-arid ecosystems and entrain particles from the ground surface. Fires produce abundant charcoal across savannahs and the resulting blackened surfaces create a large albedo contrast. Whirlwinds have been observed associated with active fires; yet, there are few published observations on post-fire landscapes. Spatiotemporal patterns of whirlwinds have been documented for a limited number of regions and have not been made for the ecosystems of eastern Africa. From field-based sightings in the Serengeti National Park, Tanzania, we report on whirlwinds over burned savannah patches that entrained large quantities of charcoal to produce black coloured charcoal devils that lofted charcoal into the atmosphere. Two occurrences of charcoal devils were sighted and photographed, one each in the Western Corridor (Bunda District) and Lamai (Serengeti District), Mara Region. The observations were compared with regional scale meteorological data and remote sensing satellite imagery and albedo estimates of the land cover conditions. Although direct meteorological or particulate matter measurements were not made, the observations show that both charcoal devils differed in colour, funnel shape, height, and savannah land cover types (different woody to grass fuel canopies), and thus different charcoal morphologies. Charcoal laden whirlwinds require further study and characterization to analyse the contribution to local-scale redistribution of matter and regional-to-global fluxes of terrestrially derived atmospheric particulates. Future research focusing on the spatiotemporal patterns of whirlwinds over burned patches of savannah, the formation, duration and dissipation mechanisms, and characterisation of the entrained material would contribute to our understanding of the phenomena. The redistribution of organic and clastic material would contribute to understanding of detrital fluxes to depositional environments, such as lakes, wetlands, and snow