51
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McMahon DE, Urza AK, Brown JL, Phelan C, Chambers JC. Modelling species distributions and environmental suitability highlights risk of plant invasions in western United States. DIVERS DISTRIB 2021. [DOI: 10.1111/ddi.13232] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Devin E. McMahon
- USDA Forest Service Rocky Mountain Research Station Reno NV USA
- USDA Forest Service Six Rivers National Forest Eureka CA USA
| | | | | | - Conor Phelan
- Department of Natural Resources and Environmental Science University of Nevada Reno NV USA
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52
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Kelly LT, Giljohann KM, Duane A, Aquilué N, Archibald S, Batllori E, Bennett AF, Buckland ST, Canelles Q, Clarke MF, Fortin MJ, Hermoso V, Herrando S, Keane RE, Lake FK, McCarthy MA, Morán-Ordóñez A, Parr CL, Pausas JG, Penman TD, Regos A, Rumpff L, Santos JL, Smith AL, Syphard AD, Tingley MW, Brotons L. Fire and biodiversity in the Anthropocene. Science 2021; 370:370/6519/eabb0355. [PMID: 33214246 DOI: 10.1126/science.abb0355] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022]
Abstract
Fire has been a source of global biodiversity for millions of years. However, interactions with anthropogenic drivers such as climate change, land use, and invasive species are changing the nature of fire activity and its impacts. We review how such changes are threatening species with extinction and transforming terrestrial ecosystems. Conservation of Earth's biological diversity will be achieved only by recognizing and responding to the critical role of fire. In the Anthropocene, this requires that conservation planning explicitly includes the combined effects of human activities and fire regimes. Improved forecasts for biodiversity must also integrate the connections among people, fire, and ecosystems. Such integration provides an opportunity for new actions that could revolutionize how society sustains biodiversity in a time of changing fire activity.
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Affiliation(s)
- Luke T Kelly
- School of Ecosystem and Forest Sciences, University of Melbourne, Parkville, Victoria 3010, Australia.
| | | | - Andrea Duane
- InForest JRU (CTFC-CREAF), 25280 Solsona, Lleida, Spain
| | - Núria Aquilué
- InForest JRU (CTFC-CREAF), 25280 Solsona, Lleida, Spain.,Centre d'Étude de la Forêt, Université du Québec à Montréal, Montreal, Quebec H3C 3P8, Canada
| | - Sally Archibald
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Natural Resources and the Environment, CSIR, Pretoria, South Africa
| | - Enric Batllori
- CREAF, Edifici C. Autonomous, University of Barcelona, 08193 Bellaterra, Barcelona, Spain.,Department of Evolutionary Biology, Ecology, and Environmental Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Andrew F Bennett
- Department of Ecology, Environment and Evolution, Centre for Future Landscapes, La Trobe University, Bundoora, Australia
| | - Stephen T Buckland
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews, Fife KY16 9LZ, UK
| | - Quim Canelles
- InForest JRU (CTFC-CREAF), 25280 Solsona, Lleida, Spain
| | - Michael F Clarke
- Department of Ecology, Environment and Evolution, Centre for Future Landscapes, La Trobe University, Bundoora, Australia
| | - Marie-Josée Fortin
- Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | | | - Sergi Herrando
- Catalan Ornithological Institute, Natural History Museum of Barcelona, 08019 Barcelona, Catalonia, Spain
| | - Robert E Keane
- U.S. Department of Agriculture Forest Service Rocky Mountain Research Station, Missoula Fire Sciences Laboratory, Missoula, MT 59808, USA
| | - Frank K Lake
- U.S. Department of Agriculture Forest Service Pacific Southwest Research Station, Albany, CA 94710, USA
| | - Michael A McCarthy
- School of BioSciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | | | - Catherine L Parr
- Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Department of Earth, Ocean & Ecological Sciences, University of Liverpool, Liverpool, UK.,Department of Zoology & Entomology, University of Pretoria, Pretoria, South Africa
| | - Juli G Pausas
- Centro de Investigaciones sobre Desertificación (CIDE-CSIC), 46113 Montcada, Valencia, Spain
| | - Trent D Penman
- School of Ecosystem and Forest Sciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Adrián Regos
- Departamento de Zooloxía, Xenética e Antropoloxía Fisica, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.,CIBIO/InBIO, Research Center in Biodiversity and Genetic Resources, ECOCHANGE Group, Vairão, Portugal
| | - Libby Rumpff
- School of BioSciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Julianna L Santos
- School of Ecosystem and Forest Sciences, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Annabel L Smith
- School of Agriculture and Food Science, University of Queensland, Gatton 4343, Australia.,Zoology, School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
| | - Alexandra D Syphard
- Vertus Wildfire, San Francisco, CA 94108, USA.,San Diego State University, San Diego, CA 92182, USA.,Conservation Biology Institute, Corvallis, OR 97333, USA
| | - Morgan W Tingley
- Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, USA
| | - Lluís Brotons
- InForest JRU (CTFC-CREAF), 25280 Solsona, Lleida, Spain.,CREAF, Edifici C. Autonomous, University of Barcelona, 08193 Bellaterra, Barcelona, Spain.,Spanish Research Council (CSIC), 08193 Bellaterra, Barcelona, Spain
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53
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Flores BM, Sá Dechoum M, Schmidt IB, Hirota M, Abrahão A, Verona L, Pecoral LLF, Cure MB, Giles AL, Britto Costa P, Pamplona MB, Mazzochini GG, Groenendijk P, Minski GL, Wolfsdorf G, Sampaio AB, Piccolo F, Melo L, Fiacador de Lima R, Oliveira RS. Tropical riparian forests in danger from large savanna wildfires. J Appl Ecol 2020. [DOI: 10.1111/1365-2664.13794] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Bernardo M. Flores
- Department of Plant Biology University of Campinas Campinas Brazil
- Graduate Program in Ecology Federal University of Santa Catarina Florianópolis Brazil
| | - Michele Sá Dechoum
- Graduate Program in Ecology Federal University of Santa Catarina Florianópolis Brazil
- Department of Ecology and Zoology Federal University of Santa Catarina Florianópolis Brazil
| | | | - Marina Hirota
- Department of Plant Biology University of Campinas Campinas Brazil
- Graduate Program in Ecology Federal University of Santa Catarina Florianópolis Brazil
- Department of Physics Federal University of Santa Catarina Florianópolis Brazil
| | - Anna Abrahão
- Department of Plant Biology University of Campinas Campinas Brazil
- Institute of Soil Science and Land Evaluation University of Hohenheim Stuttgart Germany
| | - Larissa Verona
- Department of Plant Biology University of Campinas Campinas Brazil
| | | | - Marcio B. Cure
- Graduate Program in Ecology Federal University of Santa Catarina Florianópolis Brazil
| | - André L. Giles
- Department of Plant Biology University of Campinas Campinas Brazil
- Graduate Program in Ecology University of Campinas Campinas Brazil
| | - Patrícia Britto Costa
- Department of Plant Biology University of Campinas Campinas Brazil
- School of Biological Sciences University of Western Australia Perth WA Australia
- Graduate Program in Plant Biology University of Campinas Campinas Brazil
| | | | | | | | - Géssica L. Minski
- Graduate Program in Ecology Federal University of Santa Catarina Florianópolis Brazil
| | - Gabriel Wolfsdorf
- Department of Plant Biology University of Campinas Campinas Brazil
- Graduate Program in Ecology University of Campinas Campinas Brazil
| | - Alexandre B. Sampaio
- National Centre for Biodiversity Assessment and Research and Conservation of the Brazilian CerradoChico Mendes Institute for Biological Conservation Brasilia Brazil
| | - Fernanda Piccolo
- Department of Plant Biology University of Campinas Campinas Brazil
| | - Lorena Melo
- Department of Plant Biology University of Campinas Campinas Brazil
| | | | - Rafael S. Oliveira
- Department of Plant Biology University of Campinas Campinas Brazil
- School of Biological Sciences University of Western Australia Perth WA Australia
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54
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Jarnevich CS, Young NE, Cullinane Thomas C, Grissom P, Backer D, Frid L. Assessing ecological uncertainty and simulation model sensitivity to evaluate an invasive plant species' potential impacts to the landscape. Sci Rep 2020; 10:19069. [PMID: 33149184 PMCID: PMC7643150 DOI: 10.1038/s41598-020-75325-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 10/05/2020] [Indexed: 11/18/2022] Open
Abstract
Ecological forecasts of the extent and impacts of invasive species can inform conservation management decisions. Such forecasts are hampered by ecological uncertainties associated with non-analog conditions resulting from the introduction of an invader to an ecosystem. We developed a state-and-transition simulation model tied to a fire behavior model to simulate the spread of buffelgrass (Cenchrus ciliaris) in Saguaro National Park, AZ, USA over a 30-year period. The simulation models forecast the potential extent and impact of a buffelgrass invasion including size and frequency of fire events and displacement of saguaro cacti and other native species. Using simulation models allowed us to evaluate how model uncertainties affected forecasted landscape outcomes. We compared scenarios covering a range of parameter uncertainties including model initialization (landscape susceptibility to invasion) and expert-identified ecological uncertainties (buffelgrass patch infill rates and precipitation). Our simulations showed substantial differences in the amount of buffelgrass on the landscape and the size and frequency of fires for dry years with slow patch infill scenarios compared to wet years with fast patch infill scenarios. We identified uncertainty in buffelgrass patch infill rates as a key area for research to improve forecasts. Our approach could be used to investigate novel processes in other invaded systems.
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Affiliation(s)
- Catherine S Jarnevich
- U.S. Geological Survey, Fort Collins Science Center, 2150 Centre Ave Bldg C, Fort Collins, CO, 80526, USA.
| | - Nicholas E Young
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, 80523-1499, USA
| | - Catherine Cullinane Thomas
- U.S. Geological Survey, Fort Collins Science Center, 2150 Centre Ave Bldg C, Fort Collins, CO, 80526, USA
| | - Perry Grissom
- Saguaro National Park, 3693 South Old Spanish Trail, Tucson, AZ, 85730, USA
| | - Dana Backer
- Saguaro National Park, 3693 South Old Spanish Trail, Tucson, AZ, 85730, USA.,Coronado National Forest, Tucson, AZ, 85701, USA
| | - Leonardo Frid
- Apex Resource Management Solutions Ltd, 937 Kingsmere Avenue, Ottawa, ON, K2A 3K2, Canada
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55
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Nagy RC, Fusco EJ, Balch JK, Finn JT, Mahood A, Allen JM, Bradley BA. A synthesis of the effects of cheatgrass invasion on US Great Basin carbon storage. J Appl Ecol 2020. [DOI: 10.1111/1365-2664.13770] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Emily J. Fusco
- Organismic and Evolutionary Biology University of Massachusetts Amherst MA USA
| | - Jennifer K. Balch
- Earth Lab University of Colorado Boulder CO USA
- Department of Geography University of Colorado Boulder CO USA
| | - John T. Finn
- Department of Environmental Conservation University of Massachusetts Amherst MA USA
| | - Adam Mahood
- Earth Lab University of Colorado Boulder CO USA
- Department of Geography University of Colorado Boulder CO USA
| | - Jenica M. Allen
- Miller Worley Center for the Environment Mount Holyoke College South Hadley MA USA
| | - Bethany A. Bradley
- Organismic and Evolutionary Biology University of Massachusetts Amherst MA USA
- Department of Environmental Conservation University of Massachusetts Amherst MA USA
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56
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Pik D, Lucero JE, Lortie CJ, Braun J. Light intensity and seed density differentially affect the establishment, survival, and biomass of an exotic invader and three species of native competitors. COMMUNITY ECOL 2020. [DOI: 10.1007/s42974-020-00027-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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57
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Disease-mediated ecosystem services: Pathogens, plants, and people. Trends Ecol Evol 2020; 35:731-743. [DOI: 10.1016/j.tree.2020.04.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/03/2020] [Accepted: 04/07/2020] [Indexed: 01/05/2023]
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58
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Barga SC, Olwell P, Edwards F, Prescott L, Leger EA. Seeds of Success: A conservation and restoration investment in the future of U.S.lands. CONSERVATION SCIENCE AND PRACTICE 2020. [DOI: 10.1111/csp2.209] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Sarah C. Barga
- Department of BiologyUniversity of Nevada, Reno Reno Nevada USA
- United States Department of Agriculture Forest ServiceRocky Mountain Research Station Boise Idaho USA
| | - Peggy Olwell
- Plant Conservation and Restoration Program, Bureau of Land Management Washington District of Columbia USA
| | - Fred Edwards
- Plant Conservation and Restoration Program, Bureau of Land Management Washington District of Columbia USA
- Bureau of Land Management Reno Nevada USA
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59
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Lucero JE, Seifan M, Callaway RM, Lortie CJ. Positive associations with native shrubs are intense and important for an exotic invader but not the native annual community across an aridity gradient. DIVERS DISTRIB 2020. [DOI: 10.1111/ddi.13111] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- Jacob E. Lucero
- Department of Biology York University Toronto Ontario Canada
| | - Merav Seifan
- Mitrani Department of Desert Ecology Swiss Institute for Dryland Environmental and Energy Research The Jacob Blaustein Institutes for Desert Research Ben‐Gurion University of the Negev Midreshet Ben‐Gurion Israel
| | - Ragan M. Callaway
- Division of Biological Sciences and the Institute on Ecosystems University of Montana Missoula MT USA
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60
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Jaffe DA, O’Neill SM, Larkin NK, Holder AL, Peterson DL, Halofsky JE, Rappold AG. Wildfire and prescribed burning impacts on air quality in the United States. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2020; 70:583-615. [PMID: 32240055 PMCID: PMC7932990 DOI: 10.1080/10962247.2020.1749731] [Citation(s) in RCA: 107] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
UNLABELLED Air quality impacts from wildfires have been dramatic in recent years, with millions of people exposed to elevated and sometimes hazardous fine particulate matter (PM 2.5 ) concentrations for extended periods. Fires emit particulate matter (PM) and gaseous compounds that can negatively impact human health and reduce visibility. While the overall trend in U.S. air quality has been improving for decades, largely due to implementation of the Clean Air Act, seasonal wildfires threaten to undo this in some regions of the United States. Our understanding of the health effects of smoke is growing with regard to respiratory and cardiovascular consequences and mortality. The costs of these health outcomes can exceed the billions already spent on wildfire suppression. In this critical review, we examine each of the processes that influence wildland fires and the effects of fires, including the natural role of wildland fire, forest management, ignitions, emissions, transport, chemistry, and human health impacts. We highlight key data gaps and examine the complexity and scope and scale of fire occurrence, estimated emissions, and resulting effects on regional air quality across the United States. The goal is to clarify which areas are well understood and which need more study. We conclude with a set of recommendations for future research. IMPLICATIONS In the recent decade the area of wildfires in the United States has increased dramatically and the resulting smoke has exposed millions of people to unhealthy air quality. In this critical review we examine the key factors and impacts from fires including natural role of wildland fire, forest management, ignitions, emissions, transport, chemistry and human health.
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Affiliation(s)
- Daniel A. Jaffe
- School of STEM and Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA
| | | | | | - Amara L. Holder
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - David L. Peterson
- School of Environmental and Forest Sciences, University of Washington Seattle, Seattle WA, USA
| | - Jessica E. Halofsky
- School of Environmental and Forest Sciences, University of Washington Seattle, Seattle WA, USA
| | - Ana G. Rappold
- National Health and Environmental Effects Research Lab, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
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61
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Hager HA, Ryan GD, Newman JA. Effects of elevated CO 2 on competition between native and invasive grasses. Oecologia 2020; 192:1099-1110. [PMID: 32253494 DOI: 10.1007/s00442-020-04636-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 03/30/2020] [Indexed: 11/24/2022]
Abstract
Elevated atmospheric CO2 concentration increases the performance of invasive plants relative to natives when grown in monoculture, but it is unclear how that will affect the relative competitive abilities per se of invasive and native grasses grown together. We tested competitive outcomes for four native and four invasive perennial C3 and C4 grasses under ambient (390 ppm) and elevated (700 or 1000 ppm) CO2 concentrations in the greenhouse with non-limiting water and nutrients. We predicted that elevated CO2 would increase the competitive suppression of native grasses by invasive grasses. To test this, we determined the relative interaction intensity of biomass allocation for natives grown alone vs. those grown in native-invasive species pairs. We also measured photosynthetic traits that contribute to plant invasiveness and may be affected by elevated CO2 concentrations for species pairs in mixture to determine native-invasive relative performance. We found no effect of CO2 for the aboveground biomass and tiller production measures of interaction intensity or for relative performance for most of the measured photosynthetic traits. In competition, the invaders nearly always outperform natives in biomass and tiller production, regardless of CO2 level. The results suggest that increasing CO2 concentration alone has little effect on grass competitive outcomes under controlled conditions.
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Affiliation(s)
- Heather A Hager
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada. .,Department of Biology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada.
| | - Geraldine D Ryan
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Jonathan A Newman
- School of Environmental Sciences, University of Guelph, Guelph, ON, N1G 2W1, Canada.,Department of Biology, Wilfrid Laurier University, Waterloo, ON, N2L 3C5, Canada
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62
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Characterizing Land Surface Phenology and Exotic Annual Grasses in Dryland Ecosystems Using Landsat and Sentinel-2 Data in Harmony. REMOTE SENSING 2020. [DOI: 10.3390/rs12040725] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Invasive annual grasses, such as cheatgrass (Bromus tectorum L.), have proliferated in dryland ecosystems of the western United States, promoting increased fire activity and reduced biodiversity that can be detrimental to socio-environmental systems. Monitoring exotic annual grass cover and dynamics over large areas requires the use of remote sensing that can support early detection and rapid response initiatives. However, few studies have leveraged remote sensing technologies and computing frameworks capable of providing rangeland managers with maps of exotic annual grass cover at relatively high spatiotemporal resolutions and near real-time latencies. Here, we developed a system for automated mapping of invasive annual grass (%) cover using in situ observations, harmonized Landsat and Sentinel-2 (HLS) data, maps of biophysical variables, and machine learning techniques. A robust and automated cloud, cloud shadow, water, and snow/ice masking procedure (mean overall accuracy >81%) was implemented using time-series outlier detection and data mining techniques prior to spatiotemporal interpolation of HLS data via regression tree models (r = 0.94; mean absolute error (MAE) = 0.02). Weekly, cloud-free normalized difference vegetation index (NDVI) image composites (2016–2018) were used to construct a suite of spectral and phenological metrics (e.g., start and end of season dates), consistent with information derived from Moderate Resolution Image Spectroradiometer (MODIS) data. These metrics were incorporated into a data mining framework that accurately (r = 0.83; MAE = 11) modeled and mapped exotic annual grass (%) cover throughout dryland ecosystems in the western United States at a native, 30-m spatial resolution. Our results show that inclusion of weekly HLS time-series data and derived indicators improves our ability to map exotic annual grass cover, as compared to distribution models that use MODIS products or monthly, seasonal, or annual HLS composites as primary inputs. This research fills a critical gap in our ability to effectively assess, manage, and monitor drylands by providing a framework that allows for an accurate and timely depiction of land surface phenology and exotic annual grass cover at spatial and temporal resolutions that are meaningful to local resource managers.
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63
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Fusco EJ, Finn JT, Balch JK, Nagy RC, Bradley BA. Invasive grasses increase fire occurrence and frequency across US ecoregions. Proc Natl Acad Sci U S A 2019; 116:23594-23599. [PMID: 31685633 PMCID: PMC6876192 DOI: 10.1073/pnas.1908253116] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fire-prone invasive grasses create novel ecosystem threats by increasing fine-fuel loads and continuity, which can alter fire regimes. While the existence of an invasive grass-fire cycle is well known, evidence of altered fire regimes is typically based on local-scale studies or expert knowledge. Here, we quantify the effects of 12 nonnative, invasive grasses on fire occurrence, size, and frequency across 29 US ecoregions encompassing more than one third of the conterminous United States. These 12 grass species promote fire locally and have extensive spatial records of abundant infestations. We combined agency and satellite fire data with records of abundant grass invasion to test for differences in fire regimes between invaded and nearby "uninvaded" habitat. Additionally, we assessed whether invasive grass presence is a significant predictor of altered fire by modeling fire occurrence, size, and frequency as a function of grass invasion, in addition to anthropogenic and ecological covariates relevant to fire. Eight species showed significantly higher fire-occurrence rates, which more than tripled for Schismus barbatus and Pennisetum ciliare. Six species demonstrated significantly higher mean fire frequency, which more than doubled for Neyraudia reynaudiana and Pennisetum ciliare Grass invasion was significant in fire occurrence and frequency models, but not in fire-size models. The significant differences in fire regimes, coupled with the importance of grass invasion in modeling these differences, suggest that invasive grasses alter US fire regimes at regional scales. As concern about US wildfires grows, accounting for fire-promoting invasive grasses will be imperative for effectively managing ecosystems.
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Affiliation(s)
- Emily J Fusco
- Graduate Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, MA 01003;
| | - John T Finn
- Department of Environmental Conservation, University of Massachusetts, Amherst, MA 01003
| | - Jennifer K Balch
- Earth Lab, University of Colorado, Boulder, CO 80309
- Department of Geography, University of Colorado, Boulder, CO 80309
| | | | - Bethany A Bradley
- Graduate Program in Organismic and Evolutionary Biology, University of Massachusetts, Amherst, MA 01003
- Department of Environmental Conservation, University of Massachusetts, Amherst, MA 01003
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