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--- wiki:mapping_assessment [2018/03/20 15:09] – cgiuppo
+++ wiki:mapping_assessment [2021/04/15 11:42] (current) – dbranca
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+===== Mapping and assessment =====
 === Spatial analysis of Ecosystem Services ===
 [[wiki:spatial_data|
 Spatial data]] analysis(([[https://en.wikipedia.org/wiki/Spatial_analysis|https://en.wikipedia.org/wiki/Spatial_analysis]]))  is an ensemble of techniques which study entities characterized by a precise location in space. It is commonly applied to geographic information. Georeferenced in the sense that they are typically structured as a combination of attributes (the feature associate to a given location) and a couple of values, i.e. the coordinates, identifying the location within a recognized Reference System (e.g. WGS84, UTM, etc.)\\
-Spatial analysis includes a variety of techniques, developed to derive quantitative indicators as outcomes of algorithms applied to spatial data and in particular to their topological, geometric, or geographic properties. The algorithms are typically applied to raster based [[wiki:gis|GIS]] layers, for example by means of spatial convolution indices, calculating descriptive context statistics by means of moving windows across the study area.\\
+Spatial analysis includes a variety of techniques, developed to derive quantitative [[wiki:indicators|indicators]] as outcomes of algorithms applied to spatial data and in particular to their topological, geometric, or geographic properties. The algorithms are typically applied to raster based [[wiki:gis|GIS]] layers, for example by means of spatial convolution indices, calculating descriptive context statistics by means of moving windows across the study area.\\
 In the case of spatial analysis applied to [[wiki:ecosystem_services_alpes|ES]], examples are:\\
 - Cost analysis performed by calculating a proximity (or cost) surface over a friction map, e.g. to map the potential fruition of recreational areas by tourists, or the ecological connectiveness by analysing corridors between habitats.\\
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 === ES Spatial Analysis in the AlpES Project ===
-[[:wiki:grassland_biomass|Biomass production]] for livestock uses is an ES that strictly depends on local climate and biophysical parameters. Either these spatial data are collected from local institutions or indirectly obtained from remote sensing (RM), they can be used to estimate potential productivity of pastures and grasslands. In the [[wiki:alpes|AlpES project]], statistical models are applied to quantify kg of production in dry matter per hectare, depending on the length of the growing season. The growing season is a typical proxy used to define the number of vegetation days i.e. the days in which the temperature is sufficiently high to induce biomass accumulation through synthesis of new plant tissues. For fodder production the temperature threshold was set to 5° C. Graph 1 reports the statistical models used to estimate biomass production. These models can be implemented by using simple map algebra tools, usually available in any GIS software, like QGIS and ArcGIS. A vigor factor (VF) has been assigned to each land cover as local productivity is assumed to be different depending on the specific land cover class: for example, alpine pastures have clearly higher biomass productivity compared to moors and heathland. Consequently, different growth curves have been chosen to estimate biomass growth based on the raster map that displays the number of vegetation days per cell.
+[[:wiki:grassland_biomass|Biomass production]] for livestock uses is an ES that strictly depends on local climate and biophysical parameters. Either these spatial data are collected from local institutions or indirectly obtained from [[wiki:remote_sensing|remote sensing]] (RM), they can be used to estimate potential productivity of pastures and grasslands. In the [[wiki:alpes|AlpES project]], statistical models are applied to quantify kg of production in dry matter per hectare, depending on the length of the growing season. The growing season is a typical proxy used to define the number of vegetation days i.e. the days in which the temperature is sufficiently high to induce biomass accumulation through synthesis of new plant tissues. For fodder production the temperature threshold was set to 5° C. Graph 1 reports the statistical models used to estimate biomass production. These models can be implemented by using simple map algebra tools, usually available in any GIS software, like QGIS and ArcGIS. A vigor factor (VF) has been assigned to each land cover as local productivity is assumed to be different depending on the specific land cover class: for example, alpine pastures have clearly higher biomass productivity compared to moors and heathland. Consequently, different growth curves have been chosen to estimate biomass growth based on the raster map that displays the number of vegetation days per cell.
 {{:wiki:biomass_productivity_equations.jpg?700}}
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 <font 11px/inherit;;inherit;;inherit>Figure 1. Detail of pilot region LAG Alto Bellunese: hemeroby index, where value close to 1 implies a low degree of human influence (top); number of different landcover types per km² (bottom).</font>
-[[wiki:accessibility|
-Accessibility]] is the proxy of the degree to which people can actually benefit from high recreation potentials(([[http://www.sciencedirect.com/science/article/pii/S1470160X1400168X|http://www.sciencedirect.com/science/article/pii/S1470160X1400168X]])). In AlpES project, accessibility has been calculated by means of a cost-distance algorithm(([[http://desktop.arcgis.com/en/arcmap/10.4/tools/spatial-analyst-toolbox/cost-distance.htm|http://desktop.arcgis.com/en/arcmap/10.4/tools/spatial-analyst-toolbox/cost-distance.htm]]))   (([[https://grass.osgeo.org/grass74/manuals/r.cost.html|https://grass.osgeo.org/grass74/manuals/r.cost.html]])), which determines the cumulative cost of moving to each cell on a cost surface map, from other user-specified geographic coordinates (e.g. the coordinates of the centroids of polygons representing urban areas). Each cell in the input cost map contains a value that represents the cost of moving from that cell to its neighbors. The output map displays the least cost path from each pixel of the cost surface to closest urban areas, extracted from the landcover map (CLC codes 111, 112). To quantify accessibility the cost was expressed in term of travel time.\\
+[[wiki:accessibility|Accessibility]] is the proxy of the degree to which people can actually benefit from high recreation potentials(([[http://www.sciencedirect.com/science/article/pii/S1470160X1400168X|http://www.sciencedirect.com/science/article/pii/S1470160X1400168X]])). In AlpES project, accessibility has been calculated by means of a cost-distance algorithm(([[http://desktop.arcgis.com/en/arcmap/10.4/tools/spatial-analyst-toolbox/cost-distance.htm|http://desktop.arcgis.com/en/arcmap/10.4/tools/spatial-analyst-toolbox/cost-distance.htm]]))   (([[https://grass.osgeo.org/grass74/manuals/r.cost.html|https://grass.osgeo.org/grass74/manuals/r.cost.html]])), which determines the cumulative cost of moving to each cell on a cost surface map, from other user-specified geographic coordinates (e.g. the coordinates of the centroids of polygons representing urban areas). Each cell in the input cost map contains a value that represents the cost of moving from that cell to its neighbors. The output map displays the least cost path from each pixel of the cost surface to closest urban areas, extracted from the landcover map (CLC codes 111, 112). To quantify accessibility the cost was expressed in term of travel time.\\
 Whenever an ES is estimated through a portfolio of indicators, a spatial multi-criteria analysis (MCAs) can be applied. For example, this approach has been helpful to display recreation potential hotspots in a relative and easy-to-read manner. In MCA, worth to be mentioned are the steps of normalization and aggregation:\\
 • normalization(([[https://en.wikipedia.org/wiki/Normalization_(statistics)|https://en.wikipedia.org/wiki/Normalization_(statistics) ]])) is a method used to convert data variability in a common numerical scale (0 to 1 or 0 to 100 %);\\