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Shrub encroachment into grasslands: end of an era?

Cho-ying Huang, Steven R. Archer, Mitchel P. McClaran, Stuart E. Marsh
2018 PeerJ  
Shifts in the abundance of grasses and woody plants in drylands have occurred several times during the Holocene.  ...  The study was conducted across a semi-arid landscape in southern Arizona.  ...  There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.  ... 
doi:10.7717/peerj.5474 pmid:30202645 pmcid:PMC6129137 fatcat:6mgda2cdxrdxzfahzv6wvy5zcm

Ecoregions and land cover trends in Senegal

G.G Tappan, M Sall, E.C Wood, M Cushing
2004 Journal of Arid Environments  
We monitor and quantify land use and land cover changes occurring across Senegal using nearly 40 years of satellite imagery, aerial surveys, and fieldwork.  ...  We stratify Senegal into ecological regions and present land use and land cover trends for each region, followed by a national summary.  ...  Acknowledgements This study is part of the West Africa land use and land cover trends project, funded by the US Agency for International Development (USAID)/West Africa Regional Program.  ... 
doi:10.1016/j.jaridenv.2004.03.018 fatcat:dq6kelt6tndrtozidkkkvc6oua

The Forest Types and Ages Cleared for Land Development in Puerto Rico

Todd Kennaway, E. H. Helmer
2007 GIScience & Remote Sensing  
This step relies on intersecting a map of land development from 1991 to 2000 (from the same satellite imagery) with the forest age and type maps.  ...  The extent and age distribution of each forest type that undergoes land development, however, is unknown. This study assembles a time series of four land cover maps for Puerto Rico.  ...  Forest Service (USFS) International Institute of Tropical Forestry (IITF) State and Private Forestry Program funded assembly of the historical land cover data for its Forest Legacy Program.  ... 
doi:10.2747/1548-1603.44.4.356 fatcat:kudgggrd4vghpil35xpsdmtvna

Vegetation Index Differencing for Broad-Scale Assessment of Productivity Under Prolonged Drought and Sequential High Rainfall Conditions

Dawn Browning, Caitriana Steele
2013 Remote Sensing  
This method identified areas with potential for vegetation/ecological state transition and serves to guide field reconnaissance efforts that may ultimately inform land management decisions for millions  ...  The vegetation index differencing method and translation of growing season NDVI to Z-scores permit examination of change over large areas and can be applied by non-experts.  ...  Acknowledgments We thank Jason Karl for providing helpful comments on the manuscript and acknowledge the notable contribution of the US Geological Survey for providing free access to the Landsat data archive  ... 
doi:10.3390/rs5010327 fatcat:fk3anbqo4fay7i24yadpqey4ue

Online digital archive of aerial photographs (1935–1941) of Ethiopia

Jan Nyssen, Martijn Debever, Gezahegne Gebremeskel, Bart De Wit, Kiros Meles Hadgu, Steven De Vriese, Jeffrey Verbeurgt, Amaury Frankl, Tulu Besha, Jan Kropáček, Astrid Forceville, Biadgilgn Demissie
2021 Geoscience Data Journal  
It allows adding 30 years of time depth for geographical studies, in contrast to the commonly known oldest imagery dating to 1964, sometimes 1958.  ...  The archive of aerial photographs, dating 1935-1941 and covering parts of north and central of Ethiopia, is one of the few archives with pre-1960 remotely sensed data in Africa.  ...  Further, Koen Hufkens (Harvard University), Neil Munro (Mekelle University) and Maarten Wynants (University of Plymouth) hinted available archives of historical aerial photographs covering parts of Africa  ... 
doi:10.1002/gdj3.115 fatcat:t6fclvk5dnhkhfxoxzujbkiak4

Object-oriented image analysis for mapping shrub encroachment from 1937 to 2003 in southern New Mexico

Andrea S. Laliberte, Albert Rango, Kris M. Havstad, Jack F. Paris, Reldon F. Beck, Rob McNeely, Amalia L. Gonzalez
2004 Remote Sensing of Environment  
The use of object-based classification has advantages over pixel based classification for the extraction of shrubs from panchromatic aerial and high-resolution satellite imagery.  ...  appearance of grass cover, aerial photos provide an invaluable historic record for monitoring shrub encroachment into a desert grassland.  ...  Acknowledgments This research was funded by the USDA Agricultural Research Service and the National Science Foundation Long-Term Ecological Research Program, Jornada Basin IV: Linkages in Semiarid Landscapes  ... 
doi:10.1016/j.rse.2004.07.011 fatcat:jqiqn4wujnedzhpdpgznx6qwmm

Quantifying historical changes in habitat availability for endangered species: use of pixel- and object-based remote sensing

Robert M. Pringle, Mindy Syfert, Jonathan K. Webb, Richard Shine
2009 Journal of Applied Ecology  
Using digitized aerial photographs of four sites from 1941 and 1971, and a Quickbird satellite image from 2006, we estimated the trend in habitat availability for a well-studied population of H. bungaroides  ...  For some animal species, relative habitat availability can be estimated using time series of aerial photographs, but the limited information in old black-and-white images makes it challenging to estimate  ...  We extend special thanks to the Branner Earth Sciences Library at Stanford University for its cooperation and assistance.  ... 
doi:10.1111/j.1365-2664.2009.01637.x fatcat:vem4yun2gng4rllrl4ciivzz4a

Use of Remote Sensing to Support Forest and Wetlands Policies in the USA

Audrey L. Mayer, Ricardo D. Lopez
2011 Remote Sensing  
Acknowledgements The authors would like to thank Brad Quayle at the USDA Forest Service, Remote Sensing Applications Center for assistance with Forest Service case studies and reports.  ...  Older aerial photography and Landsat imagery can be used to establish historic baselines for land cover types, and to project the impacts of different policies onto land use trends through alternative  ...  The Landsat satellite series has the historical breadth and appropriate resolution to provide historic national-scale baselines for forest cover back into the 1970s [69] ; the baseline is critical for  ... 
doi:10.3390/rs3061211 fatcat:r4vbp3ihfjegriv6ey7obqej7y

Estimating Woody Plant Density from Aerial Photographs in Communal and Leasehold Land Tenure Systems in Northwest Botswana

O. P. Dube
2008 Journal of Environmental Informatics  
Information on woody plant density (WPD) is important for assessing impacts of land use, climate variability and climate change in semi-arid lands.  ...  Previous studies in Botswana have used visual methods with the aid of a portable microscope with 40× magnification to estimate WPD from counts of apices of shadows of woody plants on air photographs.  ...  Financial support was from the European Union University of Botswana Manpower Development Fund and the Australian Centre for International Agricultural Research.  ... 
doi:10.3808/jei.200800117 fatcat:ddvdwcu3t5glzbpl6len7wvyne

Remote sensing of vegetation in the Sudano-Sahelian zone: A literature review from 1975 to 2014

Martin Karlson, Madelene Ostwald
2016 Journal of Arid Environments  
Satellite and aerial remote sensing (RS) constitute key technologies for improving the availability of vegetation data, and consequently the preconditions for scientific analysis and monitoring.  ...  ; ii) the contribution of African authors is low, potentially signaling a need for an increased transfer of knowledge and technology from developed countries; iii) RS has primarily been used to analyze  ...  The authors thank Heather Reese, Tina Neset, David Bastviken, Åsa Danielsson and Rasmus Fensholt for valuable input to the manuscript.  ... 
doi:10.1016/j.jaridenv.2015.08.022 fatcat:fvoj6zzmmnehjb6lsxmuzmeuga

Evaluating Landscape Degradation Along Climatic Gradients During the 1930s Dust Bowl Drought From Panchromatic Historical Aerial Photographs, United States Great Plains

Kasey C. Bolles, Steven L. Forman
2018 Frontiers in Earth Science  
There is a rich historical aerial photographic record of the USGP which provides an unparalleled view of past landscapes and allows for evaluation of surficial response to drought beyond the satellite  ...  This study classified the extent and loci of surficial denudation from seamless mosaics of radiometrically corrected and georectified digitized aerial negatives acquired in the late 1930s from six counties  ...  ACKNOWLEDGMENTS We are grateful to National Archives staff for research assistance and material access and to Dirk Burgdorf of AAA Research for aerial photograph reproduction.  ... 
doi:10.3389/feart.2018.00153 fatcat:m3ar3hwywvaupnyf5tkptyf3du

Recent trends and remaining challenges for optical remote sensing of Arctic tundra vegetation: A review and outlook

Alison Beamish, Martha K. Raynolds, Howard Epstein, Gerald V. Frost, Matthew J. Macander, Helena Bergstedt, Annett Bartsch, Stefan Kruse, Victoria Miles, Cemal Melih Tanis, Birgit Heim, Matthias Fuchs (+4 others)
2020 Remote Sensing of Environment  
Research was broadly categorized into four major themes of (1) time series, including NDVI trends and shrub expansion; (2) disturbance and recovery, including tundra fires, winter warming, herbivory, permafrost  ...  A B S T R A C T A systematic review and inventory of recent research relating to optical remote sensing of Arctic vegetation was conducted, and thematic and geographical trends were summarized.  ...  This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 689443 via project iCUPE (Integrative and Comprehensive Understanding  ... 
doi:10.1016/j.rse.2020.111872 fatcat:gpprd3is7ff33fhtuh4go7nu44

INTEGRATING LANDSCAPE ASSESSMENT AND HYDROLOGIC MODELING FOR LAND COVER CHANGE ANALYSIS

Scott N. Miller, William G. Kepner, Megan H. Mehaffey, Mariano Hernandez, Ryan C. Miller, David C. Goodrich, K. Devonald, Daniel T. Heggem, W. Paul Miller
2002 Journal of the American Water Resources Association  
Simulation results for the San Pedro indicate that increasing urban and agricultural areas and the simultaneous invasion of woody plants and decline of grasslands resulted in increased annual and event  ...  These changes, observed using a series of remotely sensed images taken in the 1970s, 1980s, and 1990s, have been implicated in the alteration of the basin hydrologic response.  ...  data from the classified satellite imagery, resulting in a suite of 24 simulation runs.  ... 
doi:10.1111/j.1752-1688.2002.tb05534.x fatcat:77bywnu5rfccvpckmm5nwwq4x4

An Automated Approach to Map the History of Forest Disturbance from Insect Mortality and Harvest with Landsat Time-Series Data

Christopher Neigh, Douglas Bolton, Mouhamad Diabate, Jennifer Williams, Nuno Carvalhais
2014 Remote Sensing  
We found that only harvest and insect mortality events can be mapped with adequate accuracy with a non-annual Landsat time-series. This limited our land cover understanding of NDVI decline drivers.  ...  Our algorithm provides a basic approach to map disturbance history where large impacts to forest stands have occurred and highlights the limited spectral sensitivity of Landsat time-series to outbreaks  ...  Acknowledgments This study was made possible by NASA's Terrestrial Ecology program under grants NNH08ZDA001N-TE and NNH10ZDA001N-CARBON.  ... 
doi:10.3390/rs6042782 fatcat:zwmvfgzuvjbr7h2o765kpdzxai

Assessing the Resilience of Coastal Wetlands to Extreme Hydrologic Events Using Vegetation Indices: A Review

Subrina Tahsin, Stephen C. Medeiros, Arvind Singh
2018 Remote Sensing  
Coastal wetlands (CWs) offer numerous imperative functions that support a diverse array of life forms that are poorly adapted for other environments and provide an economic base for human communities.  ...  shoreline; and sprawl of built areas.  ...  Acknowledgments: A.S. acknowledges support from Tsinghua University and the Donors of the American Chemical Society Petroleum Research Fund. The data presented in this paper is publicly available.  ... 
doi:10.3390/rs10091390 fatcat:kkvoba4mcfhhzp2l4tea74dkdy
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