160
the two species maps generated through the two airborne campaigns. A variety of
management activities were taking place in the stabilised dune ecosystem as a consequence of the plan for the conservation of Iberian lynx (Lynx pardinus), which
included clearing selected shrubland regions. Those cleared areas can be seen in the
INTA- AHS sub-scenes in Fig. 5. In the 2005 map, E. scoparia, H. halimifolium, and
R. officinalis are present in the area, whereas in the 2008 map R. officinalis totally
disappears and H. halimifolium has a reduced presence. This change was not due to
clearance activities and instead to a perturbation episode in the winter of 2007. Very
low temperatures led to frosts that prevented the species from colonising the crest of
the dunes.
Conclusions
In this work, the most widely used procedures in airborne imaging spectroscopy,
field spectroscopy for plant endmember generation, and spectral unmixing were
selected to establish a standard protocol for plant species mapping. The spatiallyexplicit distribution of plant species generated by the airborne imaging spectroscopy maps help to obtain a better knowledge of the spatial distribution of species
and their relationships with the ecological processes and perturbations that take
place on the ecosystem.
We generated fraction cover maps for the dominant shrub species in Doñana
National Park (Erica scoparia, Halimium. halimifolium, Ulex australis, Rosmarinus
officinalis and Stauracanthus genistoides) in 2005 and 2008 using the INTA-AHS
image data. The comparison between the species cover and the ground survey cover
estimates in the images, indicated a correlation that was higher for E. scoparia,
H. halimifolium and R. officinalis, but lower for U. australis and S. genistoides.
Being able to map and monitor the spatial distribution of vegetation at the species level, and identify changes in population in space and time can help to understand the shifts in species composition in response to environmental changes
induced by climate and land use change as well as other human activities. Since
2002, there has been a long term integrated ecological monitoring programme in
DBR, with a substantial increase in the monitoring of relevant ecological variables
(Díaz-Delgado 2010). The mapping protocols based on airborne and ground-based
spectroscopy can be integrated within monitoring programs in the DNS but also in
other protected areas and their surrounds.
Acknowledgments The authors would like to thank the staff from Doñana Biological Station and
Biological Reserve who helped us during different stages of this study. The authors also recognise
the knowledge of the staff of Instituto Nacional de Técnica Aeroespacial (INTA) Remote Sensing
Group for performing the airborne campaigns and the geometric correction of the AHS images.
The airborne campaigns were funded by the Spanish Ministry of Science and Innovation through
the research projects HYDRA (No.CGL2006-02247/BOS) and HYDRA2 (CGL2009-09801/
BOS). We appreciate the contribution of Antonio Pou for his helpful direction in the work.
M. Jiménez and R. Díaz-Delgado
the two species maps generated through the two airborne campaigns. A variety of
management activities were taking place in the stabilised dune ecosystem as a consequence of the plan for the conservation of Iberian lynx (Lynx pardinus), which
included clearing selected shrubland regions. Those cleared areas can be seen in the
INTA- AHS sub-scenes in Fig. 5. In the 2005 map, E. scoparia, H. halimifolium, and
R. officinalis are present in the area, whereas in the 2008 map R. officinalis totally
disappears and H. halimifolium has a reduced presence. This change was not due to
clearance activities and instead to a perturbation episode in the winter of 2007. Very
low temperatures led to frosts that prevented the species from colonising the crest of
the dunes.
Conclusions
In this work, the most widely used procedures in airborne imaging spectroscopy,
field spectroscopy for plant endmember generation, and spectral unmixing were
selected to establish a standard protocol for plant species mapping. The spatiallyexplicit distribution of plant species generated by the airborne imaging spectroscopy maps help to obtain a better knowledge of the spatial distribution of species
and their relationships with the ecological processes and perturbations that take
place on the ecosystem.
We generated fraction cover maps for the dominant shrub species in Doñana
National Park (Erica scoparia, Halimium. halimifolium, Ulex australis, Rosmarinus
officinalis and Stauracanthus genistoides) in 2005 and 2008 using the INTA-AHS
image data. The comparison between the species cover and the ground survey cover
estimates in the images, indicated a correlation that was higher for E. scoparia,
H. halimifolium and R. officinalis, but lower for U. australis and S. genistoides.
Being able to map and monitor the spatial distribution of vegetation at the species level, and identify changes in population in space and time can help to understand the shifts in species composition in response to environmental changes
induced by climate and land use change as well as other human activities. Since
2002, there has been a long term integrated ecological monitoring programme in
DBR, with a substantial increase in the monitoring of relevant ecological variables
(Díaz-Delgado 2010). The mapping protocols based on airborne and ground-based
spectroscopy can be integrated within monitoring programs in the DNS but also in
other protected areas and their surrounds.
Acknowledgments The authors would like to thank the staff from Doñana Biological Station and
Biological Reserve who helped us during different stages of this study. The authors also recognise
the knowledge of the staff of Instituto Nacional de Técnica Aeroespacial (INTA) Remote Sensing
Group for performing the airborne campaigns and the geometric correction of the AHS images.
The airborne campaigns were funded by the Spanish Ministry of Science and Innovation through
the research projects HYDRA (No.CGL2006-02247/BOS) and HYDRA2 (CGL2009-09801/
BOS). We appreciate the contribution of Antonio Pou for his helpful direction in the work.
M. Jiménez and R. Díaz-Delgado