Introduction
Landscapes are often classified to monitor biodiversity
levels in a region. As they are
constantly being reformed over time through geological processes like erosion,
weathering, and sedimentation (Kim et al 2021, 2), so are the distributions of
organisms that live there. In this
study, the Korean Peninsula was topologically monitored using various
techniques to classify its landscapes, mainly involving remote sensing
techniques. Biological habitats were
classified using satellite imagery, a digital elevation model (DEM), weather
data, and biological survey data (ibid. 2).
The findings could potentially apply to the conservation of land and
biodiversity on the Korean Peninsula.
Literature Review
Research on the Korean Peninsula is necessary to
establish biogeographic regions that would promote land conservation (ibid. 2). Damage to landforms caused by anthropogenic
use and climate change need to be considered when delineating these regions, since
both are encroaching on ecosystems around the world (ibid. 2). There are many ways humans and climate change
impact ecosystems, including contamination of water, land, and air, and the destruction
or reduction of habitat. Thus, the
investigation of microclimates associated with bioregional communities should
be recorded for government evaluation.
Background and
Geographical Context
The
Korean Peninsula is in East Asia along the Pacific Coast, at a mid-latitude
location (ibid. 2). Because of its
proximity to the ocean, it experiences “simultaneous influences of continental
and maritime climates” (ibid. 2). High
altitude locations are on the north and east of the peninsula, while the south contains
more soil-rich environments (ibid. 2). There
are many forests on the peninsula, mainly in the lowlands but also in subalpine
areas (ibid. 2-3), with many varieties of deciduous and coniferous trees. The variety of these attributes suggests a
broad range of bioregions in the area.
Methods Used
Remote sensing was the main resource used for
the study. According to Gomez and Jones
(2010, 56), remote sensing involves collecting data on the earth’s surface that
isn’t through direct contact. Rather, indirect
contact is used through data collected by sensors on satellite or airborne
instruments, which transmit information about the earth’s surface in a variety
of ways, including light detection (Lidar), infrared, and photogrammetry. The researcher can extract this data by
downloading it from a public domain server (ibid. 158) that is typically
offered by a government organization.
Processing the data is a key step in the process, as a lot of it comes
from raw information that is meaningless without referencing. For instance, geometric correction and
geo-referencing are required (ibid. 162) because images are inherently
distorted due to variations in terrain and sensor imperfections. This geoprocessing is typically done through
a GIS package, inevitably being convenient because the images can be mapped on
it as well.
In
the North Korean study, a variety of data was downloaded from public domain
websites to create a landscape hierarchy with the assistance of remote sensing.
The DEM was downloaded from USGS.gov to
map elevation of the terrain (Kim et al 2021, 3). A DEM is a representation of the ground that
excludes surface objects (USGS, n.d.), deriving from either a topographic map,
radar from satellites, or Lidar. Because
the DEM did not cover every land classification, other remote sensing tools
were needed. A digital topographic map
(DTM) was downloaded from the Korea National Geographic Information Institute to
be used for the classification of small habitats (ibid. 4). The DTM provides a digital model of terrain for
precision measurements and optimal planning (Innoter, n.d.). Sentinel 2 satellite images were also used to
evaluate areas in which the DTM could not be used (ibid. 4), providing data on
vegetation cover to help determine classification boundaries.
These
maps and images were compiled to be indexed on a classification map that was
based on the DEM. A diversity index was
calculated for each grid cell on the output raster (ibid. 5), while relief
analysis was used to classify major landform elements (ibid. 5). Relief analysis is an evaluation of the
distance between highest and lowest points on a landform. Spatial information for watersheds, a key
bioregional indicator, “was extracted from the DEM using the hydrological
modeling tool in ArcGIS” (ibid. 6). The hydrological
modeling tool allows a GIS user to determine flow direction and delineate
watersheds based on a DEM raster (ESRI, n.d.).
All these elements were normalized for the raster map, which the
researchers found most useful to classify habitats.
Analysis and Discussion
62 main habitat types and 437 sub-habitat types were
found on the Korean Peninsula using these methods (ibid. 18). Landforms were categorized into mountain
types, plains, alluvial landforms, coast landforms, Baekdudaegan, and the
demilitarized zone (ibid 18). A factor
analysis of the classifications found that aspect, slope, landform, and
biodiversity had the greatest effect on biological communities (ibid. 11). Factor analysis is a way of simplifying a
broad range of variables by reducing them to fewer numbers of factors (Statistics
Solutions, n.d.). Because remote sensing
can uncover so many attributes, the researchers were able to use multiple
sources to classify areas based on this factor analysis.
A
drawback is that remote sensing can be elaborate and complicated, especially
when so many variables are involved. For
instance, this study had many components that a lay person wouldn’t understand,
but a seasoned geographer would. Measurement
uncertainty and resolution errors can also pose a problem.
Conclusion
Remote sensing was
a valuable tool in the study because it allowed the researchers to classify
numerous landforms without having to directly observe them. It was also a convenient way to retrieve
information on the ecosystems of the Korean Peninsula. Though there were resolution issues, the
researchers corrected them by normalizing the data. The study is beneficial for conservation
efforts on the peninsula because it clearly delineates the boundaries where
indicator species flourish.
Bibliography
E.S.R.I.
“Hydrology Analysis Sample Applications”. Accessed March 5, 2024. https://pro.arcgis.com/en/pro-app/latest/tool-reference/spatial-analyst/hydrologic-analysis-sample-applications.htm
Gomez,
Basil, and John Paul Jones III. Research Methods in Geography.
Chichester: Blackwell Publishing Ltd, 2010.
Innoter. “Digital Topographic Maps.” Accessed March 5, 2024. https://innoter.com/en/services/kartografiya/digital-topographic-maps/
Kim Nam Shin,
Jin Yeol Cha and Chi Hong Lim. Hierarchical Landform Delineation for the Habitats
of Biological Communities on the Korean Peninsula. Plos One 16, no. 11
(2021): 1-22. https://doi.org/10.1371/journal.pone.0259651
Statistics
Solutions. “Factor Analysis”. Complete Dissertation. Accessed March 3, 2024. https://www.statisticssolutions.com/free-resources/directory-of-statistical-analyses/factor-analysis/
U.S.G.S. “What is a Digital Elevation Model?”. Accessed March 5, 2024. https://www.usgs.gov/faqs/what-digital-elevation-model-dem
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