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Poster:
Measuring Long-Term Ecological Changes across
Populated Landscapes
Erle C. Ellis, Hongqing Wang, Hong Sheng Xiao, Kui Peng, Xin Ping Liu, Shou Cheng Li, Hua Ouyang, Xu Cheng, and Lin Zhang Yang
Measuring ecological changes across highly
heterogeneous anthropogenic landscapes is made
difficult by their small scale of management, in which
numerous land managers impact multiple small landscape
features using a wide variety of inputs and methods.
To map and measure ecological changes at the fine
scale at which they occur in anthropogenic landscapes,
we have developed a standardized feature-based
approach to ecological mapping that links the direct
interpretation of high resolution (¡Ü1 m) imagery with
groundtruthing in the field. Using a four-level
hierarchical combination of standardized
classification terms, landscapes are stratified into
ecologically-distinct components, or "ecotopes", for
efficient sampling and measurement of ecological
variables. The ecotope classification system
characterizes all stable land use systems employed by
local land managers in rural, suburban, and urban
landscapes, so that data obtained directly from land
managers can be integrated with ecological
measurements to make spatially-explicit high
resolution ecological change estimates across
landscapes. The system effectively identified
significant ecological changes between the 1940s/50s
and the current time across five 1 km2 sites located
in densely populated agricultural regions across
China, and in suburban and urban Baltimore, Maryland
USA. Standardized comparisons across sites
demonstrate the role of environmental and economic
constraints in modulating the ecological impacts of
land use and land cover change.
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