ZEF Bonn

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ZEF Bonn ● Center for Development Research – Annual Report 2001/2002
ZEF's terrestrial ecosystem
research program focuses on
change processes in two areas:
at the ecosystem edge where
land conversion is taking place,
such as forest and desert margins,
and in areas where landuse
practices are leading to
land degradation.
3. Department of Ecology and Natural Resource
Management
The depletion of raw materials, shifts in material and energy flows, degradation of
biodiversity, and landscape changes are exerting a critical strain on the global environment.
Understanding these changes is not only a major challenge for science,
but also a prerequisite for designing policies and actions to alter the course of
events or temper their effects.
Within ZEF's terrestrial ecosystem research program, change processes require attention
in two areas: at the ecosystem edge where land conversion is taking place in
areas such as forest margins, wetland margins, and desert margins, and in areas
where land-use practices are leading to land degradation, and ultimately to the need
for new land. The principal units of analysis range from plot to watershed level.
An important aim of an integrated landscape analysis involving all components (soil,
air, water, plants, animals and human use) is the valuation of services provided by
natural ecosystem components. These special ecosystem values must also be put in
the context of agricultural productivity and trade (or substitution) options, particularly
when societal resources are called upon to improve sustainability or preserve
ecosystem function.
3.1 Atmosphere and Water Management
3.1.1 Carbon cycling and greenhouse gas emissions
Human-induced changes in natural systems or land use have a direct impact on the
atmosphere. Processes such as emissions of CO2, methane and nitrous oxide from
soils or from biomass burning remain poorly understood.
Wetlands store a huge amount of carbon in the soil and cover vast areas worldwide.
Their destruction would lead to an additional input of CO2 into the atmosphere.
Wetlands are also important centres of diversity for both flora and fauna and
regulate the water balance in the landscape. Sound concepts for a wise use of wetlands
are needed to comply both with the Ramsar Convention in favour of nature
conservation and the UN Framework Convention on Climate Change to forestall
emission of greenhouse gases.
ZEF is working towards a better understanding of land-use change in wetlands as
well as development options that offer environmentally and economically viable
alternatives. It has therefore elaborated a new research program on wetland development.
An initial study compiles a global inventory of wetlands and their carbon
pools based on vegetation and soil maps. This inventory will assist in identifying the
stocks of soil organic carbon and their density distributions in the global wetlands
and thus the hotspots of potential greenhouse gas (GHG) emissions under ongoing
development.
The global inventory is supplemented by in-depth studies on land-use change on
regional scales. One case study on wetlands in the Lake Victoria Basin has been
initiated in collaboration with the International Centre for Research in Agroforestry
(ICRAF). Carbon dioxide emissions involved in land use change will be quantified in
two steps: first by an analysis of remote sensing images and then by a characterisa-