Geoscience Reference
In-Depth Information
Methods in wetland research
3
3.1 Introduction
• Meso landscape - bog complex, mesotope,
or
Grossmoor
made up of many individual
components.
• Macro landscape - mire system consisting of
multiple bogs, lakes, streams, intervening
uplands, and related features.
Wetland environments comprise water, soil,
vegetation, and wildlife. Thus, all manner of
physical and biological scientii c methods may
be applied for investigations, which range from
microscopic laboratory analysis to space-borne
satellite observations of continental regions.
When human inl uence is added, then various
cultural and socioeconomic approaches may
be integrated into wetland studies. In other
words, potential methods for wetland research
are quite diverse and include nearly all scien-
tii c means used to study the Earth's environ-
ments and human interactions with those
environments.
The dean of Estonian mire research, Viktor
Masing, reviewed historical issues of wetland
mapping, research and classii cation, particu-
larly in Germany, Russia and Scandinavia (Masing
1998). The earliest studies were limited neces-
sarily to ground-based observations, which were,
and still are, logistically difi cult to accomplish
in many bog, marsh and swamp situations. By
the 1930s, aerial photography had already come
into use for geobotanical mapping purposes,
and three basic levels or scales were recognized
for mire classii cation (Galkina 1946):
From this beginning, Masing (1984) elaborated
a multi-level research approach (Table 3-1). His
classii cation scheme was developed specii cally
for mires in the boreal and subboreal regions of
the northern hemisphere. Nonetheless, its basic
structure could be adapted for other types of
wetlands in different regions. In addition to the
spatial dimensions of this scheme, the temporal
element must be added (Charman 2002). All
wetlands are dynamic through time, either
because of internal evolution (autogenic change)
or forcing from external factors (allogenic
change). Time scales vary from diurnal to
millennial.
Here we emphasize those methods that reveal
the spatial relationships of organic and inor-
ganic constituents and temporal variability that
characterize wetland environments, namely geo-
graphic information systems (GIS) and remote
sensing (RS). GIS/RS must be combined with
conventional i eld observations and sampling
in order to provide ground truth for validating,
analyzing, and interpreting the remotely sensed
information. It is this multi-level approach that
yields comprehensive and convincing results.
• Micro landscape - individual hummocks,
ridges, hollows, pools and other forms
within bogs.
