TY - JOUR
T1 - Effects of Morella faya tree invasion on aboveground carbon storage in Hawaii
AU - Asner, Gregory P.
AU - Martin, Roberta E.
AU - Knapp, David E.
AU - Kennedy-Bowdoin, Ty
N1 - Funding Information:
Acknowledgments We thank T. Varga, J. Mascaro, and G. Sanchez for their work on the field measurements. Access to field sites was provided by the US National Park Service. This study was supported by NASA Terrestrial Ecology and Biodiversity Program grant NNG-06-GI-87G and the Carnegie Institution. The Carnegie Airborne Observatory is supported by the W.M. Keck Foundation and William Hearst III.
PY - 2010/3
Y1 - 2010/3
N2 - The negative effects of biological invasion are often the focus of ecological studies, but few have considered potential positive impacts, such as increased carbon storage, resulting from invasion. We combined airborne imaging spectrometer and LiDAR (light detection and ranging) observations with field measurements to assess if the highly invasive nitrogen-fixing tree Morella faya alters canopy 3-D structure and aboveground biomass (AGB) along a 1,500 mm precipitation gradient in Hawaii. Airborne analysis of canopy water content, leaf nitrogen concentration, fractional canopy cover, and vegetation height facilitated mapping of native- and Morella-dominated canopies in rainforest, woodland-savanna and shrubland ecosystems, with Morella detection errors ranging from 0 to 13.4%. Allometric equations were developed to relate the combined LiDAR and spectral data to field-based AGB estimates (r2 = 0.97, P < 0.01), and to produce a map of biomass stocks throughout native and invaded ecosystems. The structure of the invasive Morella canopies varied by ecosystem type, and the invader shaded out native understory plants in rainforest zones. Despite a 350% increase in AGB going from shrubland to rainforest, Morella did not increase average AGB in any ecosystem it invaded. Furthermore, spatial distributions of biomass indicated that Morella decreased maximum AGB in the woodland-savanna ecosystems. We conclude that Morella tree invasion does not enhance aboveground carbon stocks in any ecosystem it invades in Hawaii, thereby minimizing its contribution to this potentially important ecosystem service. We also found that the fusion of spectral and LiDAR remote sensing provided canopy chemical and structural data facilitating a landscape assessment of how biological invasion alters on carbon stocks and other ecosystem properties.
AB - The negative effects of biological invasion are often the focus of ecological studies, but few have considered potential positive impacts, such as increased carbon storage, resulting from invasion. We combined airborne imaging spectrometer and LiDAR (light detection and ranging) observations with field measurements to assess if the highly invasive nitrogen-fixing tree Morella faya alters canopy 3-D structure and aboveground biomass (AGB) along a 1,500 mm precipitation gradient in Hawaii. Airborne analysis of canopy water content, leaf nitrogen concentration, fractional canopy cover, and vegetation height facilitated mapping of native- and Morella-dominated canopies in rainforest, woodland-savanna and shrubland ecosystems, with Morella detection errors ranging from 0 to 13.4%. Allometric equations were developed to relate the combined LiDAR and spectral data to field-based AGB estimates (r2 = 0.97, P < 0.01), and to produce a map of biomass stocks throughout native and invaded ecosystems. The structure of the invasive Morella canopies varied by ecosystem type, and the invader shaded out native understory plants in rainforest zones. Despite a 350% increase in AGB going from shrubland to rainforest, Morella did not increase average AGB in any ecosystem it invaded. Furthermore, spatial distributions of biomass indicated that Morella decreased maximum AGB in the woodland-savanna ecosystems. We conclude that Morella tree invasion does not enhance aboveground carbon stocks in any ecosystem it invades in Hawaii, thereby minimizing its contribution to this potentially important ecosystem service. We also found that the fusion of spectral and LiDAR remote sensing provided canopy chemical and structural data facilitating a landscape assessment of how biological invasion alters on carbon stocks and other ecosystem properties.
KW - Airborne remote sensing
KW - Alien invasive species
KW - Biological invasion
KW - Biomass
KW - Hyperspectral
KW - Imaging spectroscopy
KW - LiDAR
KW - Light detection and ranging
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U2 - 10.1007/s10530-009-9452-1
DO - 10.1007/s10530-009-9452-1
M3 - Article
AN - SCOPUS:77952881520
SN - 1387-3547
VL - 12
SP - 477
EP - 494
JO - Biological Invasions
JF - Biological Invasions
IS - 3
ER -