Geoscience Reference
In-Depth Information
resource management) offer several cornerstone contributions towards the under-
standing of biodiversity within environmental geography. Human activities and
management determine the status of biodiversity (including biodiversity-supporting
processes) in a wide range of environments. The perspectives in this section centre
on humanised landscapes (anthropogenic habitats) that vary from near-wilderness-
type settings to ones that are extremely modifi ed. As a result, there is a gradient of
impacts on biodiversity that begins, on one end, with such activities as relatively
low-impact land use, exemplifi ed through the gathering of non-timber forest prod-
ucts (NTFPs) and rotational shifting cultivation. Forest regrowth and regeneration
as a result of land use abandonment is another example of low-impact, indeed
generally positive, effects on biodiversity (similar to low-impact autogenic distur-
bances described on pages 54-56). At the other end of this gradient are activities
with high-level impacts on biodiversity, such as permanent forest clearing, agricul-
tural land use that varies from conventional systems to expansion of biotechnology-
based agriculture along with urban and industrial development.
Biodiversity-impacting activities are related to socio- and political economic pro-
cesses at scales ranging from local to regional and global. The latter scale is especially
salient, since biodiversity impacts are a major form of global human-environmental
change. The 'Global Change' and 'Global Human Environmental Change' networks
of researchers, scientifi c institutions, and policy specialists have singled out biodiver-
sity loss, along with climate change, desertifi cation, and water resources, as key issues
of planetary biogeophysical systems involving human-environment interactions.
'Scaling up' the estimates and understanding of biodiversity impacts, from local and
regional studies to the global scale, is an important and continued challenge. Many
human-environment interactions involving biodiversity do not lend themselves to
straightforward spatial extrapolation - they are uneven as a result of underlying
spatial variation in both the human-social dynamics as well as the environment-
biodiversity interactions. Nonetheless, considerable progress in understanding in
biodiversity-scale relationships have been made recently thanks to new or expanding
techniques, many including Geographic Information Systems (GIS) and remote
sensing (RS), as well as other innovative forms of research design and analysis, such
as multiple case studies, cross-regional comparisons, and meta-analysis.
Research into Land Use/Cover Change, or LUCC, involves several of the above
techniques that are frequently applied to understanding the impacts of human activi-
ties on biodiversity in forest ecosystems (Velazquez et al., 2003). Frequently it
evaluates the changes in the spatial parameters of forest cover (e.g., the extent and
patterning of forest edge, overall shape, and other geometric and distance-related
features) in comparison to non-forest areas. Typically cast as diachronic compari-
sons involving two or more time periods this approach offers a means of estimating
cover-related impacts with inferences about biodiversity. Also, LUCC is increasingly
linked to intensive studies of human-social and ecological-change processes that are
georeferenced and coded into the frameworks of spatial analysis. The emphasis of
LUCC on forest-and-other-land-use-areas, while well suited to remote sensing and
other land-cover analysis, has thus far precluded the analysis using this approach
of other forms of biodiversity impacts, such as changes
within
agricultural and
urban land use. These latter changes include the increasingly important impact of
biotechnology-based agriculture. Here the impact on biodiversity is concentrated
within agricultural systems (agrobiodiversity), which is of interest in the global-
change research and policy networks as well as those related to food security and
rights.
