17
With respect to content, the dataset can contain all classes in the area, or only target
classes. Likewise, it can have mixtures and gradients between classes included, or
(un-)intentionally excluded from the dataset. Sample sizes can be more or less
evenly spread over the classes, or highly skewed. Also, the data can be topical or
(partially) outdated. In some cases, reference data can even be completely absent.
All these aspects affect the potential outcome and application of specific remote
sensing methods to a certain degree. Given the currently limited sharing of reference data (Pettorelli et al. 2014), which further impedes the availability of similar
reference data over different areas, the impact of ground reference data availability
on remote sensing method transferability cannot be disregarded.
Image Properties Differ
In common with ground reference data, image data also come in a variety of forms.
Not only do specifications for each sensor differ (number and location of bands,
band widths and spectral sensitivities, spatial and radiometric resolutions, known
Fig. 2 Histogram of the number of habitat (sub) types in which a given indicator is used in the
Flemish manual for conservation status assessments (T’jollyn et al. 2009). The majority of the
indicators are used for one or a few habitat (sub) types only
Towards a Mature Age of Remote Sensing for Natura 2000 Habitat Conservation: Poor…
With respect to content, the dataset can contain all classes in the area, or only target
classes. Likewise, it can have mixtures and gradients between classes included, or
(un-)intentionally excluded from the dataset. Sample sizes can be more or less
evenly spread over the classes, or highly skewed. Also, the data can be topical or
(partially) outdated. In some cases, reference data can even be completely absent.
All these aspects affect the potential outcome and application of specific remote
sensing methods to a certain degree. Given the currently limited sharing of reference data (Pettorelli et al. 2014), which further impedes the availability of similar
reference data over different areas, the impact of ground reference data availability
on remote sensing method transferability cannot be disregarded.
Image Properties Differ
In common with ground reference data, image data also come in a variety of forms.
Not only do specifications for each sensor differ (number and location of bands,
band widths and spectral sensitivities, spatial and radiometric resolutions, known
Fig. 2 Histogram of the number of habitat (sub) types in which a given indicator is used in the
Flemish manual for conservation status assessments (T’jollyn et al. 2009). The majority of the
indicators are used for one or a few habitat (sub) types only
Towards a Mature Age of Remote Sensing for Natura 2000 Habitat Conservation: Poor…