Development and provision of resources to improve professional practice in satellite-based observation for mapping land cover and forest structure
Submitting Institution
Aberystwyth UniversityUnit of Assessment
Geography, Environmental Studies and ArchaeologySummary Impact Type
EnvironmentalResearch Subject Area(s)
Environmental Sciences: Environmental Science and Management
Agricultural and Veterinary Sciences: Forestry Sciences
Engineering: Geomatic Engineering
Summary of the impact
The mapping and monitoring of land cover, habitats and forest structure
through satellite-based observation by government and commercial
organisations around the world has been enhanced by data analysis
techniques and tools developed by the Earth Observation and Ecosystem
Dynamics (EOED) Laboratory at Aberystwyth University (AU). This has
allowed new commercial services to be provided and has change professional
working practices. The key impacts include (i) improved knowledge and
information about land cover and environmental change in forest and
brigalow ecosystems in Australia, supporting effective management
strategies; (ii) the completion of a comprehensive digital map of habitats
in Wales to inform policy-making; and (iii) the increased capacity of the
global remote sensing community in forest characterisation using open
source software developed by AU.
Underpinning research
The overarching aim of research in EOED since 1999 has been the
application of Earth Observation (EO) technology for large-scale mapping
over broad areas using automated techniques for environmental monitoring.
Research has particularly focused on a) furthering the field of remote and
automated land-cover mapping, b) developing methods for extracting
bio-physical parameters (e.g., above-ground biomass (AGB)), c) ecosystem
dynamics including detecting and understanding the processes of change,
and d) developing new technologies and research impact through the design
and open release of software. EOED staff, led by Lucas (1999-2013) and
Bunting (2007-11 & 2012-) have worked closely and collaboratively with
many partners around the world, including academic, government and
industry organizations, producing world-class research, as summarised
below:
(i) Land-cover and — use mapping. EOED led research from 2003
demonstrating the benefits of an object-orientated rule-based approach to
classifying habitats from optical satellite imagery, which has been
applied subsequently to Wales to update the previous ground-based Phase I
habitat mapping3.1. More recently EOED have developed a new
generic approach to mapping land covers and habitats and changes in these
in and around protected sites in Europe as part of the FP7 BIOSOS project
(2010-13)3.2.
(ii) Extraction of biophysical parameters. Over the period since
1999, EOED have worked at multiple scales to develop methods for
retrieving AGB from EO data. For Australia, EOED established the
requirements for using ALOS PALSAR data acquired under conditions of
minimal surface moisture to provide more reliable retrieval of AGB and
detection of vegetation change3.3. To support retrieval from
PALSAR data, EOED collated significant forest inventory datasets (over
2500 plots and several million trees) ranging from sparse woodlands to
dense tropical forests to establish a biomass library for Queensland,
which is being extended to Australia thereby supporting national mapping
and monitoring through a combination of PALSAR, Landsat and ICESAT data.
An element of building the biomass library has been to include estimates
obtained by scaling field-based measures using high resolution airborne
(e.g., LIDAR) data3.4.
(iii) Ecosystem Dynamics. EOED have actively participated in the
collaborative Injune Landscape Collaborative Project (ILCP) since 2000,
and have used its research area in central Queensland as a supersite
allowing development of new algorithms3.5,3.6 for retrieving
biophysical attributes and detecting change (e.g., in biomass, structure)
through continued acquisition of airborne and spaceborne sensors operating
in different modes and supporting on-ground measurements at the tree and
stand level. These data continue to provide an unprecedented opportunity
to improve understanding of ecosystem response to change but also unique
opportunities for calibration and validation of biomass and biomass-change
maps derived from spaceborne data. Work undertaken in the Brigalow Belt
Bioregion of southeast Queensland has resulted in the development of a new
approach for differentiating and mapping different forest growth stages of
the endangered brigalow ecosystems that integrates both ALOS PALSAR and
Landsat-derived Foliage Projected Cover (FPC) data and avoids the
requirement for use of dense time-series for mapping regrowth forests3.7.
Knowledge from the ILCP has also contributed to developing understanding
of microwave3.8 and LiDAR interaction with forest canopies
through parameterisation simulation models3.9.
(iv) New technologies and Software. To support the research being
undertaken within EOED several new algorithms and techniques have been
developed. These include innovative image and lidar processing software
tools and data storage formats within the RSGISLib,3.10 SPDLib3.11,3.12
and KEA libraries3.13. These packages have allowed for
consistent and rapid processing of airborne and spaceborne SAR, optical
and LiDAR data at regional and national scales, while providing support
for high performance computing (HPC) systems.
References to the research
Land-cover and use mapping
3.1 Journal Article: Lucas, R.M. et al., (2011). Updating
the Phase 1 habitat map of Wales, UK, using satellite sensor data. ISPRS
Journal of Photogrammetry and Remote Sensing 66, pp 81-102. DOI:
10.1016/j.isprsjprs.2010.09.004
3.2 Research Grant: BIOdiversity multi-SOurce monitoring System:
from Space to Species (BioSOS). Lucas, R.M., and Bunting, P. EU FP7.
€101,340 of €247,6363. 01.12.2010 - 30.11.2014.
Extraction of biophysical parameters
3.3 Journal Article: Lucas, R.M. et al., (2010). An
evaluation of the ALOS PALSAR L-band backscatter — Above ground biomass
relationship Queensland, Australia: Impacts of surface moisture condition
and vegetation structure. IEEE Journal of Selected Topics in Applied
Earth Observations and Remote Sensing 3, 576-593. DOI:
10.1109/JSTARS.2010.2086436
3.4 Journal Article: Lucas, R.M. et al., (2008).
Retrieving forest biomass through integration of CASI and LiDAR data. International
Journal of Remote Sensing 29(5), 1553-1577. DOI:
10.1080/01431160701736497
Ecosystem Dynamics
3.5 Journal Article: Lucas, R.M. et al., (2008).
Classification of Australian forest communities using aerial photography,
CASI and HyMap data. Remote Sensing of Environment 112(5),
2088-2103. DOI: 10.1016/j.rse.2007.10.011
3.6 Journal Article: Bunting, P. et al., (2010).
Characterisation and mapping of forest communities by clustering
individual tree crowns. Remote Sensing of Environment 114,
2536-2547. DOI: 10.1016/j.rse.2010.05.030
3.7 Journal Article: Clewley, D. et al., (2012). An
Approach to Mapping Forest Growth Stages in Queensland, Australia through
Integration of ALOS PALSAR and Landsat Sensor Data. Remote Sensing
4(8), 2236-2255. DOI: 10.3390/rs4082236
3.8 Journal Article: Burgin, M. et al., (2011). A
generalized radar backscattering model based on wave theory for multilayer
multispecies vegetation. IEEE Transactions on Geoscience and Remote
Sensing 49(12), 4832-4845. DOI: 10.1109/TGRS.2011.2172949
3.9 Journal Article: Armston J. et al. (2013). Direct
retrieval of canopy gap probability using airborne waveform lidar. Remote
Sensing Of Environment 134, 24-38. DOI: 10.1016/j.rse.2013.02.021
New technologies and Software
3.10 Journal Article: Bunting P. et al., (2013) The
Remote Sensing and GIS Software Library. Computers and Geosciences,
Available early-online. DOI: 10.1016/j.cageo.2013.08.007
3.11 Journal Article: Bunting, P. et al., (2013). Sorted
pulse data (SPD) library. Part I: A generic file format for LiDAR data
from pulsed laser systems in terrestrial environments. Computers and
Geosciences 56, 197-206. DOI: 10.1016/j.cageo.2013.01.019
3.12 Journal Article: Bunting, P. et al., (2013). Sorted
pulse data (SPD) library. Part II: A processing framework for LiDAR data
from pulsed laser systems in terrestrial environments. Computers and
Geosciences 56, 207-215. DOI: 10.1016/j.cageo.2013.01.010
3.13 Journal Article: Bunting, P. & Gillingham, S., (2013).
The KEA image file format. Computers and Geosciences 57, 54-58.
DOI: 10.1016/j.cageo.2013.03.025
Details of the impact
Research by the EOED has had a direct impact on the professional practice
of individuals and organisations involved in monitoring vegetation change
and developing and implementing conservation policies, from government,
industry and agency scientists engaged in collating and interpreting data,
to field conservationists. Due to the collaborative nature of the research
undertaken within EOED, which has involved staff visits for extended
periods (in both directions) and regular interchange of ideas, software
and datasets, the outputs and methodologies developed through this
research have been incorporated into their collaborators' everyday working
practices. By improving the information available to agencies involved in
monitoring environmental change and making conservation decisions, the
research has also had a secondary, indirect impact on the environment,
supporting measures to protect endangered habitats in Australia and
Europe.
Three key impacts of the research can be highlighted:
i) Improved knowledge and information about land cover and
environmental change in forest and brigalow ecosystems in Australia,
supporting effective management strategies.
Research by EOED has developed of new techniques for the use of ALOS
PALSAR data and Landsat-derived Foliage Projected Cover (FPC) data in
quantifying and mapping vegetation cover, structure and biomass. This has
been applied to improving knowledge about forests and specifically the
brigalow ecosystems in Queensland, Australia5.1. As the
Assistant Director-General for Science Delivery in the Queensland
Government Department of Environment and Resource Management has
confirmed, the application of AU research in the period since 2008 has
generated new policy options for managing vulnerable ecosystems:
"The partnership with Aberystwyth has significantly added to the global
knowledge of how the information content of radar and optical data can be
integrated for discriminating and mapping the growth stage of vegetation
communities. In a study of the entire Brigalow Belt Bioregion in southeast
Queensland, an area of over 36.5 million ha was mapped using a combination
of ALOS PALSAR and Landsat sensor data to derive four stages of growth:
cleared areas, regrowth, mature and remnant of Brigalow dominated
communities. Such information has contributed to knowledge of the
distribution of carbon and biodiversity and provided options for
management of these vulnerable ecosystems"5.2.
Data processing and methodological innovation by AU has further enabled
the Queensland Government to strengthen its own technical capacity to use
satellite-based observation data in its operational programmes:
"Targeted research at the Injune study area (established in 2000 by
Professor Lucas and colleagues in Queensland) using airborne hyperspectral
imagery and LiDAR has resulted in methods for mapping regrowth stages,
individual tree species, tree death and changes in tree cover over the
reporting period. As a result of this research, the Queensland Government
has improved validation of several core products, including Foliage
Projective Cover (from Landsat sensor and LiDAR data), and is in a much
better position to take advantage of future radar, LiDAR and hyperspectral
satellites for operational programs."5.2
Additionally, the Queensland Government has benefited from the
development of its researchers' skills and knowledge base through staff
exchanges and cooperation with AU, such that "the work with Aberystwyth
University provided an important link to extend our base knowledge for
mapping at the Statewide and continental level"5.2.
Methods and data products developed by AU have also been used in the
expansion of biomass mapping from Queensland to the rest of Australia,
with a woody biomass map of Australia due for completion in late 20135.1,5.3.
The Queensland Governments notes the critical contribution of Lucas and
the EOED in facilitating this project:
"Professor Richard Lucas has been the key collaborator and responsible
for establishing and maintaining the links with the Japanese Aerospace
Exploration Agency (JAXA) which have resulted in cost-free access to ALOS
PALSAR imagery for Australia"5.4.
ii) The completion of a comprehensive digital map of habitats in Wales
to inform policy-making.
An object-orientated rule-based approach to classifying habitats
developed by the EOED has been applied since 2010 to the production of the
Habitat Inventory for Wales, in collaboration with Natural Resources Wales
(NRW)5.5 and commercial partner Environment Systems Ltd5.6.
The inventory updated the previous Phase I habitat map5.7,
which had been produced from field observations, and made Wales the first
country in Europe to have a national habitat map produced from
satellite-based observation data5.8. The map was identified as
available evidence for natural resource management by the Welsh Government
consultation on its Sustaining a Living Wales Green Paper in 2012
("We have a complete survey of our terrestrial habitats, now being
repeated using remote sensing"5.9), which informed the
development of a new integrated approach to natural resource management in
Wales. Furthermore, the development of the Earth Observation Dynamic
Habitat Mapping (EODHAM) system, a generic technique based on the Food and
Agriculture (FAO) Land Cover Classification Scheme (LCCS) for generating
classifications of land covers and translating these to General Habitat
Categories (GHCs). The EODHAM system is now being used within number of
collaborative projects with NRW through which field ecologists are being
trained in EO and the use of EO imagery alongside some automated is now
becoming an accepted method of working within NRW, a significant change in
work practices5.5.
This research that led to the new Phase I map for Wales has also formed
"a foundation enabling Environment Systems to developed a wider commercial
service using remote sensing that is now highly regarded across the UK and
overseas"5.6. The research from EOED has therefore directly led
to the expansion of the services Environment Systems are offering, with
the service having been applied within "England, Scotland, Republic of
Ireland, Canada, Anguilla and Georgia"5.6.
iii) The increased capacity of the global remote sensing community in
forest characterisation using open source software developed by EOED.
Open-source software developed by Bunting within EOED has been adopted
for use in forest and land-cover characterisation, mapping and monitoring
by public agencies and commercial organizations worldwide. Remote Sensing
and GIS Software Library (RSGISLib) software has been downloaded 1659
times since January 2009, and Sorted Pulse Data Software Library (SPDLib)
software downloaded 1412 times over the same period (data captured
20/10/135.10). Software in the KEA file format has been
installed and is in use by a number of institutions including the
Queensland State Government (Australia) and has been downloaded >112
times since August 20125.10. Additionally, the python scripting
training materials made available by EOED has been download 321 times
since February 20135.10. The benefits from using this software
have been described by the Manager of the Remote Sensing Centre in the
Queensland Government Department of Environment and Resource Management:
"Open source software tools developed by Peter Bunting and colleagues, in
particular RSGISLib and SPDLib, have enabled more efficient storage and
operational analysis of remotely sensed datasets including LiDAR and high
resolution optical data. These software tools are used daily by up to 35
scientists within the Remote Sensing Centre, Queensland Government"5.2.
Sources to corroborate the impact
5.1 Letter from Director of the Terrestrial Ecosystem Research Network
(TERN), University of Queensland.
5.2 Letter from Assistant Director General — Science Delivery, Queensland
Government, Australia.
5.3 Letter from Japanese Exploration Agency (JAXA).
5.4 Queensland Government Remote Sensing Centre website,
http://www.nrm.qld.gov.au/science/remote-sensing/partnerships.html
5.5 Letter from Conservation Monitoring Advisor, NRW.
5.6 Letter from Director of Environment Systems Ltd.
5.7 `Habitat Inventory for Wales', http://www.gwylio.org.uk
5.8 `Satellite wildlife map of Wales could be EU "first"', BBC News
website, 2 November 2010,
http://www.bbc.co.uk/news/uk-wales-11672184
5.9 Welsh Government (2012) Consultation Document: Sustaining a
Living Wales, A Green Paper on a new approach to natural resource
management in Wales, WG13943, page 23,
http://wales.gov.uk/docs/desh/consultation/120210nefgreenpaperen.pdf
5.10 Download data from sourceforge.net and bitbucket.org, where the
files and source code are hosted.