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Earth Observation approaches to
sustainable land management in drylands:
experiences from the European Space Agency
Marc Paganini, Anna Burzykowska and Frank Martin Seifert, European Space Agency;
Ute Gangkofner, GeoVille; and Thomas Häusler, GAF AG
T
he European Space Agency (ESA) has been collab-
orating with the United Nations Convention to
Combat Desertification (UNCCD) since the World
Summit on Sustainable Development in 2002, develop-
ing and delivering Earth Observation (EO) solutions that
can be used, with little adaptation, by UNCCD parties to
better combat desertification and land degradation and
mitigate their effects for the benefit of local communities
and in particular poor rural societies.
The approach taken by ESA responds to the strategic objec-
tives of the convention with the provision of EO solutions that
can improve both the living conditions of affected populations
and the conditions of the ecosystems they depend on. Global
approaches are needed to deliver consistent data to support
national assessments and reporting, while local approaches are
essential to respond to the specificities of rural communities
who are facing different land degradation realities. The exam-
ples shown below address both global and local EO approaches
to sustainable land management in drylands.
Global EO data sets and approaches for national
assessment and reporting on land degradation
During its eighth session in Madrid in 2007, the UNCCD
Conference of the Parties adopted a 10-year strategic plan
elaborated around three strategic objectives that include, as
the second objective, the goal to improve the conditions of
affected ecosystems. A number of indicators were developed
and refined along the years, resulting in 2013 with the adop-
tion of six global indicators, comprehensively called progress
indicators. The indicators adopted to monitor the conditions
of ecosystems are the ‘trends in land cover’ and the ‘trends in
land productivity and functioning of the land’. These global
indicators were accompanied by the necessity to develop
mechanisms to encourage parties to develop their national
indicators. This requires the development of cost-effective and
scientifically sound global solutions that can be adapted to
national specificities.
ESA has a long-standing experience in developing global
and consistent data sets from EO missions. One of ESA’s
most recent and ambitious programmes is its Climate Change
Initiative (CCI) that aims at producing long-term climate data
records of key parameters of the Earth System. The objective
is to provide long-term and accurate satellite-based measures
of Essential Climate Variables (ECVs) that have been defined
by the Global Climate Observing System to serve the data
needs of the Intergovernmental Panel on Climate Change in
its assessment of the state and evolution of the climate system.
The ECVs include a number of terrestrial variables, such as
land cover, which it is essential to monitor for the modelling
of carbon and water cycles. The ESA CCI has produced a set of
consistent global land cover maps at 300 m spatial resolution
for the epochs 2000, 2005 and 2010 and is currently extend-
ing the temporal series to the years 1990 and 2015 (see case
study). These global land cover data sets have been provided
to UNCCD and constitute an excellent baseline for countries
when measuring changes in land cover and stratifying their
national assessment on land degradation.
Monitoring trends in land productivity is a necessity for coun-
tries that face the adverse conditions of living in drylands and
is one of the UNCCD indicators to track progress in improving
the conditions of ecosystems. EO approaches for measuring
land productivity at global scale have been developed but have
to deal with the complexity of phenomena. Best solutions are
based on time series of proxies of Net Primary Productivity,
a measure of the net flux of carbon from the atmosphere into
organic matters and a fundamental ecological variable that indi-
cates the conditions of healthy or degraded land.
The ESA Diversity II project has developed an innovative
method based on the inter- and intra-annual fluctuations of
Fraction of Absorbed Photosynthetically Active Radiation
(fAPAR), a physical parameter that measures the ability of
vegetation to absorb the energy of the solar radiation and
generate green leaf biomass. fAPAR is one of the biophysical
variables that can best monitor plant productive capacity in
terrestrial ecosystems. Satellite-based fAPAR time series were
analysed to extract a number of phenological parameters
(such as the start and end of the vegetation year, growing
and dry seasons) and to compute productivity parameters
by integrating fAPAR values during the different vegetation
periods. By analysing their fluctuations through the years,
a set of indicators on the conditions of the ecosystems and
on trends in productivity can be derived. These indicators
can be used to analyse specific land degradation phenomena
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