Which ecosystems?
This manual mainly makes a distinction between the different natural ecosystems. In addition, agriculture and urbanized areas are also discussed because nature often disappears in favor of or is created at the expense of these land uses. To the extent that small landscape elements (KLE) can be found on the available maps, they are subdivided into the ecosystem class to which they belong. This manual does not provide information about the benefits of green elements in urban environments. For this we refer to Aertsens et al. (2012) and to the manual for the Nature Value Explorer City (Hendrix. et al. 2015).
The classification of ecosystems, based on discussions in the steering group, international typologies and the INBO advisory note (Thoonen, Vriens and Van Reeth 2012), was simplified so that the classes could be derived from the available maps.
Rivers and still waters​
This concerns all surface waters, both flowing and still waters. Water is drained via rivers, which originate as smaller streams and grow into wide rivers downstream. Still waters can vary greatly in depth, ranging from several tens of meters to less than one meter. Still waters of good ecological quality contain clear water and many floating and submerged aquatic plants. Still waters naturally arise at lower locations in the landscape where water comes together and remains. These are pools, lakes and fens (shallow lake on sandy soil). Over the years, humans have created water features such as puddles after the extraction of raw materials.
Wet nature​
This category is subdivided into inland wetlands and flat plains/marches.
In wetlands, the water level is close to the ground surface all year round or the areas are flooded for a long time. This causes a specific vegetation of swamp plants to develop. Wetlands also occur at the transition from water biotopes to land biotopes. This concerns the floating plant mats of densely growing waters. Peats also belong to this class. The character of this terrain type is determined by the accumulation of plant remains under wet conditions. Peats can be fed by both groundwater (low peat) and rainwater (active raised peat). Swamp forests fall under the group 'forests'. For the sake of a few specific available figures, we make a distinction within wetland vegetation between reed vegetation and other wetland vegetation.
An estuary is the downstream part of a river that is influenced by the tidal action of the sea. Vegetations adapted to the saline to brackish environment occur here: flat plains and marshes. Outside the floodbank they occur in the Scheldt estuary, the IJzer estuary, the Zwin and the Baai of Heist. Forested marshes can be found under the category of forests (alluvial forests).
Heathland and shrubs​
Heathland vegetation mainly occurs on very nutrient-poor, sandy soils. The vegetation consists mainly of heath plants, mosses and lichens. To preserve the remaining heathland, management is required to replace previous agricultural practices. The evolution into forests is slowed down by mowing, sowing, burning and grazing.
Shrubs also fall under this category. Shrubs contain mature, woody shrubs and some young trees. a.o. gale shrub, sea buckthorn shrub, gorse, bird cherry...
Grasslands and tall herbs​
In addition to grasses, various types of flowers and herbs occur in flower- and species-rich grasslands and tall herbs. These grasslands are also rich in animal species, such as invertebrates and birds. These grasslands are remains of former agriculture, when few chemical fertilizers and pesticides were used. The grasslands are occasionally mowed or grazed.
The distinction between 'grasslands and tall herbs' and 'cropland and meadows' is, both ecologically and purely visually/landscape, fairly arbitrary. INBO has issued advice on this subject based on the Biological Valuation Map (see background information in the Nature Value Explorer).
Forests​
In forests, trees mainly determine the view, but there is usually also a wide variety of herbaceous plants, shrubs, mosses and fungi. Forest management can focus on the conservation, restoration or development of biodiversity, on a range of functions and ecosystem services or exclusively on commercially viable wood production. The forests are classified according to commercial wood types and furthermore into deciduous forest, coniferous forest or mixed forest. Alluvial forests are also categorized separately.
Cropland or meadows​
On these lands, the yield of agricultural crops, fruit growing or livestock farming prevails. The natural values are of secondary importance. This also includes orchards. Attention can be paid to natural values, for example by restoring and preserving small landscape elements (KLE). To the extent that they can be identified on the land use map, they are placed in a separate land use category. Not all KLE have been mapped across Flanders. A definition of this KLE can be found in Appendix C.
Sparsely vegetated land​
This category bundles land uses with little or no vegetation. This includes the high beach and the unvegetated dunes. Areas with pioneer vegetation, for example in the seaports, are also included. Inland drifting dunes also fall into this category. Dunes consist of sand accumulations with or without vegetation of grasses, herbs and mosses. Shrubs and trees may also occur. The dunes with vegetation cannot be found under this category, but under grasslands, shrubs or forests respectively.
Urban land use​
Any form of land use that involves hardening of the soil falls under urban land use. This includes residential areas including gardens, industry (including green layout of the site = other gardens, excluding green buffer zones if larger than 100m²) and infrastructure (sports fields, airports, roads and railways). This category is divided into buildings, gardens, roads and squares and other urbanized areas. When it comes to a completely urban case, it is better to use the urban module.
Sea​
The sea is a marine ecosystem, characterized by salt water as its main component. This concerns shallow coastal waters. The estuaries that also partly contain salt water fall into a separate category. Currently, no ecosystem services for marine habitats are included in the Nature Value Explorer.