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Aim

This vignette has been created to illustrate the creation of spatial inputs to be used in model simulations with the package, starting from a set of coordinates corresponding to arbitrary locations. The functions introduced in this document are meant to be executed sequentially to progressively add spatial information, as illustrated in the workflow below, but users are free to use them in the most convenient way.

Initialisation workflow for continuous landscapes

Before reading this vignette, users should be familiar with forest and soil structures in package medfate. Moreover, a brief introduction to spatial structures used in medfateland package is given in vignette Package overview and examples are given in vignettes Spatially-uncoupled simulations and Watershed simulations.

Let’s first load necessary libraries:

Target area

Any spatial data set should begin with the definition of spatial elements. Here we will use a watershed in Catalonia as example, which we will describe using cells of 200 m in EPSG:32631 (UTM for fuse 31) projection.

First we load a polygon data set describing watersheds in Spain and select our target watershed (Riera de Bianya [river code “2005528”]):

dataset_path <- "~/OneDrive/EMF_datasets/"
scchh <- terra::vect(paste0(dataset_path, "Hydrography/Sources/Spain/CuencasMedNorte_Pfafs/M_cuencas_rios_Med_Norte.shp"))
watershed <-terra::project(scchh[scchh$pfafrio =="2005528",], "epsg:25831")
watershed
##  class       : SpatVector 
##  geometry    : polygons 
##  dimensions  : 1, 8  (geometries, attributes)
##  extent      : 444922.8, 459850.8, 4668354, 4678487  (xmin, xmax, ymin, ymax)
##  coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
##  names       : OBJECTID COD_MAR cod_uni pfafrio       nom_rio_1 Cuen_Tipo
##  type        :    <int>   <chr>   <int>   <chr>           <chr>     <chr>
##  values      :    63564       M 1001395 2005528 RIERA DE BIANYA        NA
##  Shape_Leng Shape_Area
##       <num>      <num>
##   4.905e+04  1.024e+08

We can draw a map with the location of the watershed within Catalonia using:

dataset_path <- "~/OneDrive/EMF_datasets/"
counties <- terra::vect(paste0(dataset_path, "PoliticalBoundaries/Sources/Catalunya/Comarques/comarques.shp"))
ggplot()+
  geom_spatvector(data = counties)+
  geom_spatvector(fill = "black", data = watershed)+
  theme_bw()

Location of the watershed within Catalonia

Now we define a raster at 200 m resolution, including the target area. We intersect it with the watershed boundaries to keep the target locations:

res <- 200
r <-terra::rast(terra::ext(watershed), resolution = c(res,res), crs = "epsg:25831")
v <- terra::intersect(terra::as.points(r), watershed)

And finally we transform the result into a sf object:

x <- sf::st_as_sf(v)[,"geometry", drop = FALSE]
x
## Simple feature collection with 2550 features and 0 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 445022.8 ymin: 4668454 xmax: 459822.8 ymax: 4678454
## Projected CRS: ETRS89 / UTM zone 31N
## First 10 features:
##                    geometry
## 1  POINT (450222.8 4678454)
## 2  POINT (449422.8 4678254)
## 3  POINT (449622.8 4678254)
## 4  POINT (449822.8 4678254)
## 5  POINT (450022.8 4678254)
## 6  POINT (450222.8 4678254)
## 7  POINT (450422.8 4678254)
## 8  POINT (450622.8 4678254)
## 9  POINT (450822.8 4678254)
## 10 POINT (451022.8 4678254)

We will use the raster definition for plots.

rm(v)
gc()
##           used  (Mb) gc trigger  (Mb) max used  (Mb)
## Ncells 2082861 111.3    4218464 225.3  2552903 136.4
## Vcells 3514434  26.9   10146329  77.5 10130659  77.3

Topography and land cover type

Topography

Once an object sf has been defined with target locations, we need to determine topographic features (elevation, slope, aspect) and land cover corresponding to those locations. You should have access to a Digital Elevation Model (DEM) at a desired resolution. Here we will use a DEM raster for Catalonia at 30 m resolution, which we load using package terra:

dem <- terra::rast(paste0(dataset_path,"Topography/Products/Catalunya/MET30m_ETRS89_UTM31_ICGC.tif"))
dem
## class       : SpatRaster 
## dimensions  : 9282, 9391, 1  (nrow, ncol, nlyr)
## resolution  : 30, 30  (x, y)
## extent      : 258097.5, 539827.5, 4485488, 4763948  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source      : MET30m_ETRS89_UTM31_ICGC.tif 
## name        : met15v20as0f0118Bmr1r050 
## min value   :                   -7.120 
## max value   :                 3133.625

Having a digital elevation model, we can use function add_topography() to extract elevation and calculate aspect and slope:

y_0 <- add_topography(x, dem = dem)
##  Checking inputs
##  Checking inputs [17ms]
## 
##  Defining column 'id'
##  Defining column 'id' [13ms]
## 
##  Extracting topography
## |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          
##  Extracting topography [11.6s]
## 
y_0
## Simple feature collection with 2550 features and 4 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 445022.8 ymin: 4668454 xmax: 459822.8 ymax: 4678454
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 2,550 × 5
##              geometry    id elevation slope aspect
##           <POINT [m]> <int>     <dbl> <dbl>  <dbl>
##  1 (450222.8 4678454)     1      886.  9.62   66.7
##  2 (449422.8 4678254)     2     1000.  6.86   45.2
##  3 (449622.8 4678254)     3      932. 32.8   134. 
##  4 (449822.8 4678254)     4      853. 20.8   164. 
##  5 (450022.8 4678254)     5      832. 22.6   154. 
##  6 (450222.8 4678254)     6      811. 29.6   137. 
##  7 (450422.8 4678254)     7      792. 30.7   195. 
##  8 (450622.8 4678254)     8      831. 21.4   146. 
##  9 (450822.8 4678254)     9      822. 27.6   234. 
## 10 (451022.8 4678254)    10      846. 28.0   185. 
## # ℹ 2,540 more rows

We can check that there are no missing values in topographic features using:

##  No missing values in topography.

We can now examine the elevation of the area, using the raster r to draw cells instead of points:

## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.

Elevation map

Land cover type

In addition to topography, users should have access to a land cover map, in this case we will use a land cover raster for Catalonia, issued in 2018:

lcm <- terra::rast(paste0(dataset_path,"LandCover/Sources/Catalunya/cobertes-sol-v1r0-2018.tif"))
lcm
## class       : SpatRaster 
## dimensions  : 259198, 267234, 1  (nrow, ncol, nlyr)
## resolution  : 1, 1  (x, y)
## extent      : 260170, 527404, 4488784, 4747982  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source      : cobertes-sol-v1r0-2018.tif 
## color table : 1 
## name        : cobertes-sol-v1r0-2018

Users should examine the legend of their land cover map and decide how to map legend elements to the five land cover types used in medfateland. After inspecting our land cover map legend, we define the following vectors to perform the legend mapping:

agriculture <- 1:6
wildland <- c(7:17,20)
rock <- 18:19
artificial <- 21:35
water <- 36:41

Having these inputs, we can use add_land_cover() to add land cover to our starting sf:

y_1 <- add_land_cover(y_0, 
                      land_cover_map = lcm, 
                      wildland = wildland, 
                      agriculture = agriculture, 
                      rock = rock, 
                      artificial = artificial, 
                      water = water, progress = FALSE)
y_1
## Simple feature collection with 2550 features and 5 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 445022.8 ymin: 4668454 xmax: 459822.8 ymax: 4678454
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 2,550 × 6
##              geometry    id elevation slope aspect land_cover_type
##           <POINT [m]> <int>     <dbl> <dbl>  <dbl> <chr>          
##  1 (450222.8 4678454)     1      886.  9.62   66.7 wildland       
##  2 (449422.8 4678254)     2     1000.  6.86   45.2 wildland       
##  3 (449622.8 4678254)     3      932. 32.8   134.  wildland       
##  4 (449822.8 4678254)     4      853. 20.8   164.  wildland       
##  5 (450022.8 4678254)     5      832. 22.6   154.  wildland       
##  6 (450222.8 4678254)     6      811. 29.6   137.  wildland       
##  7 (450422.8 4678254)     7      792. 30.7   195.  wildland       
##  8 (450622.8 4678254)     8      831. 21.4   146.  wildland       
##  9 (450822.8 4678254)     9      822. 27.6   234.  wildland       
## 10 (451022.8 4678254)    10      846. 28.0   185.  wildland       
## # ℹ 2,540 more rows

As before, we can check for missing data:

##  No missing values in land cover.

We can examine the land cover types in our target area using:

Land cover map

Forest parameterization

The next step is to define forest objects for our simulations. Forests should be defined for all target locations whose land cover is defined as wildland. When forest inventory plots are not be available for the target locations, one must resort on imputations.

  1. Forest inventory data from nearby locations. National forest inventories are ideal in this respect.
  2. A forest map where polygons or raster cells describe the distribution of forest (or shrubland) types.
  3. Raster source of vegetation structure (i.e. mean tree height or basal area), derived from aerial or satellite LiDAR missions.

Our task here will be to perform imputations of forest inventory plots to our target locations according to some criteria and, if possible, to correct the forest structure on those locations according to available data.

Forest imputation

A map of forest types in the target area is important to determine dominant tree or shrub species. We start by loading the Spanish Forest Map (1:25000) for the region of Catalonia, which is in vector format, using package terra:

forest_map <- terra::vect(paste0(dataset_path,"ForestMaps/Products/Catalunya/mfe25_cat_class.shp"))
forest_map
##  class       : SpatVector 
##  geometry    : polygons 
##  dimensions  : 238096, 1  (geometries, attributes)
##  extent      : 0.1591812, 3.332506, 40.523, 42.86144  (xmin, xmax, ymin, ymax)
##  source      : mfe25_cat_class.shp
##  coord. ref. : lon/lat ETRS89 (EPSG:4258) 
##  names       :              Class
##  type        :              <chr>
##  values      : Pinus halepensis_2
##                Pinus halepensis_2
##                Pinus halepensis_2

Second, we need forest inventory data for imputations. Arguably, this is the hardest part. Let’s assume one has access to a such data already in format for package medfateland (how to build such data set will be illustrated in a different vignette). We also load an sf_nfi object that contains coordinates and forest objects corresponding to the Fourth Spanish Forest Inventory for Catalonia (5509 forest plots):

nfi_path <- "/home/miquel/OneDrive/mcaceres_work/model_initialisation/medfate_initialisation/IFN2medfate/"
sf_nfi <- readRDS(paste0(nfi_path, "data/SpParamsMED/IFN4/Catalunya/IFN4_cat_final_ETRS89H31.rds"))
sf_nfi
## Simple feature collection with 5509 features and 14 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 260943 ymin: 4491797 xmax: 518928 ymax: 4744883
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 5,509 × 15
##    Provincia Estadillo Clase Subclase IDPARCELA IDCLASE ID       id    elevation
##  * <chr>     <chr>     <chr> <chr>    <chr>     <chr>   <chr>    <chr>     <dbl>
##  1 08        0001      A     1        080001    A1      080001_… 0800…      1814
##  2 08        0002      A     1        080002    A1      080002_… 0800…      1797
##  3 08        0003      A     1        080003    A1      080003_… 0800…      1657
##  4 08        0004      A     1        080004    A1      080004_… 0800…      1403
##  5 08        0005      A     1        080005    A1      080005_… 0800…      1371
##  6 08        0006      A     1        080006    A1      080006_… 0800…      1683
##  7 08        0009      A     4        080009    A4      080009_… 0800…      1041
##  8 08        0014      A     1        080014    A1      080014_… 0800…      1538
##  9 08        0016      A     4        080016    A4      080016_… 0800…      1743
## 10 08        0020      A     1        080020    A1      080020_… 0800…      1404
## # ℹ 5,499 more rows
## # ℹ 6 more variables: slope <dbl>, aspect <dbl>, soil <list>, forest <list>,
## #   forest_allrecords <named list>, geom <POINT [m]>

Note that this is already an sf object suitable for simulations, but refers to the locations of the forest inventory plots, not to our target area.

Having these two inputs (forest map and forest inventory data), we can use function impute_forests() to perform the imputation for us (this normally takes some time):

y_2 <- impute_forests(y_1, sf_fi = sf_nfi, dem = dem, 
                      forest_map = forest_map, progress = FALSE)
## |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          
## ! 9 forest classes were not represented in forest inventory data. Geographic/topographic criteria used for 111 target locations.
##  Forest imputed on 2021 out of 2152 target wildland locations (93.9%).
##  Forest class was missing for 131 locations and forests were not imputed there.
##  Not enough plots of the same class within geographic distance limits for 21 locations. The closest plot of the same class was chosen in those cases.

For each target location, the function selects forest inventory plots that correspond to the same forest class, defined in the forest map, and are geographically closer than a pre-specified maximum distance. Among the multiple plots that can fulfill this criterion, the function chooses the plot that has the most similar elevation and position in the N-to-S slopes (i.e. the product of the cosine of aspect and slope). More details can be found in the documentation of impute_forests().

The resulting sf has an extra column named forest:

y_2
## Simple feature collection with 2550 features and 6 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 445022.8 ymin: 4668454 xmax: 459822.8 ymax: 4678454
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 2,550 × 7
##              geometry    id elevation slope aspect land_cover_type
##           <POINT [m]> <int>     <dbl> <dbl>  <dbl> <chr>          
##  1 (450222.8 4678454)     1      886.  9.62   66.7 wildland       
##  2 (449422.8 4678254)     2     1000.  6.86   45.2 wildland       
##  3 (449622.8 4678254)     3      932. 32.8   134.  wildland       
##  4 (449822.8 4678254)     4      853. 20.8   164.  wildland       
##  5 (450022.8 4678254)     5      832. 22.6   154.  wildland       
##  6 (450222.8 4678254)     6      811. 29.6   137.  wildland       
##  7 (450422.8 4678254)     7      792. 30.7   195.  wildland       
##  8 (450622.8 4678254)     8      831. 21.4   146.  wildland       
##  9 (450822.8 4678254)     9      822. 27.6   234.  wildland       
## 10 (451022.8 4678254)    10      846. 28.0   185.  wildland       
## # ℹ 2,540 more rows
## # ℹ 1 more variable: forest <list>

Only wildland locations will have a forest object, for example:

y_2$forest[[1]]
## $treeData
##            Species       DBH    Height          N      Z50  Z95
## 1     Quercus ilex 30.950000  990.0000   14.14711 702.5790 5020
## 2     Quercus ilex 24.653871 1081.7076   84.88264 702.5790 5020
## 3  Quercus petraea 24.950000 1130.0000   14.14711 209.3124 1040
## 4     Quercus ilex 19.638126  947.9476  318.30989 702.5790 5020
## 5  Quercus petraea 19.318709  831.5934   63.66198 209.3124 1040
## 6     Quercus ilex 15.219907  822.3270  572.95780 702.5790 5020
## 7  Quercus petraea 14.553801  893.6430  127.32395 209.3124 1040
## 8     Quercus ilex  9.163617  588.0669 1018.59164 702.5790 5020
## 9  Quercus petraea  8.850000  600.0000  127.32395 209.3124 1040
## 10    Quercus ilex  5.000000  300.0000 1018.59164 702.5790 5020
## 11 Quercus petraea  5.000000  400.0000  127.32395 209.3124 1040
## 12  Crataegus spp.  1.500000  100.0000  318.30989 456.0124 2862
## 13    Quercus ilex  1.500000  100.0000 1273.23955 702.5790 5020
## 14 Quercus petraea  1.500000  100.0000  318.30989 209.3124 1040
## 
## $shrubData
##         Species Cover Height      Z50  Z95
## 1  Hedera helix     5    200 173.0294  812
## 2 Erica arborea     5    160 346.1416 2000
## 3 Lonicera spp.     2    150 392.2431 2353
## 4   Prunus spp.     2     50 541.3475 3577
## 
## $herbCover
## [1] NA
## 
## $herbHeight
## [1] NA
## 
## attr(,"class")
## [1] "forest" "list"

It is important to know whether the forest inputs are complete and suitable for simulations. This can be done using function check_forests():

## ! Missing 'forest' data in 131 wildland locations (6.1%).
##  All objects in column 'forest' have the right class.
##  No missing/wrong values detected in key tree/shrub attributes of 'forest' objects.

There are some wildland locations missing forest data. These correspond to shrublands or pastures, therefore not included in the forest inventory data. At this point, we could call again impute_forests() including the option missing_class_imputation = TRUE, which would force imputation of forest inventory plots on non-forest cells. The alternative is to provide more suitable data.

Shrubland imputation

In this section we illustrate how to use function impute_forest() to impute forest objects in shrubland areas. To this aim, we use a vegetation map representing habitats of interest for the EU: Hàbitats d’interès comunitari:

veg_map <- terra::vect(paste0(dataset_path,"ForestMaps/Sources/Catalunya/Habitats_v2/Habitats_interes_com.shp"))
veg_map
##  class       : SpatVector 
##  geometry    : polygons 
##  dimensions  : 61036, 42  (geometries, attributes)
##  extent      : 260189, 526577.9, 4488766, 4747981  (xmin, xmax, ymin, ymax)
##  source      : Habitats_interes_com.shp
##  coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
##  names       :  OBJECTID  HIC1       TEXT_HIC1 RHIC1 SUP_HIC1  HIC2
##  type        :     <num> <chr>           <chr> <num>    <num> <chr>
##  values      : 4.218e+04  9340 Alzinars i car~    10     4.17    NA
##                2.444e+04  9340 Alzinars i car~     5    23.56  9540
##                 2.09e+04  9260     Castanyedes     4     5.02    NA
##        TEXT_HIC2 RHIC2 SUP_HIC2  HIC3 (and 32 more)
##            <chr> <num>    <num> <chr>              
##               NA     0        0    NA              
##  Pinedes medite~     5    23.56    NA              
##               NA     0        0    NA

In this case we use a database of 575 shrubland inventory plots in Catalonia described in Casals et al. (2023):

sfi_path <- "/home/miquel/OneDrive/mcaceres_work/model_initialisation/medfate_initialisation/Shrublands/Combuscat/"
sf_sfi <- readRDS(paste0(sfi_path, "Products/Combuscat_final.rds"))
sf_sfi
## Simple feature collection with 546 features and 6 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 267500 ymin: 4495400 xmax: 519300 ymax: 4736800
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 546 × 7
##                geom    id elevation slope aspect soil         forest      
##         <POINT [m]> <dbl>     <dbl> <dbl>  <dbl> <list>       <named list>
##  1 (345200 4574000)     5     619.  11.3     105 <df [4 × 6]> <forest [4]>
##  2 (368600 4582600)     7     695.   1.15      5 <df [4 × 6]> <forest [4]>
##  3 (362800 4586000)    24     533.   8.53    255 <df [4 × 6]> <forest [4]>
##  4 (366000 4567200)    25     274.  16.7     235 <df [4 × 6]> <forest [4]>
##  5 (349500 4576800)    29     536.  11.3      70 <df [4 × 6]> <forest [4]>
##  6 (346400 4574000)    38     707.   0       110 <df [4 × 6]> <forest [4]>
##  7 (498000 4687400)   107      73.0 14.0     340 <df [4 × 6]> <forest [4]>
##  8 (389500 4571800)   315     378.   6.84     63 <df [4 × 6]> <forest [4]>
##  9 (390200 4571400)   318     367.   8.53     12 <df [4 × 6]> <forest [4]>
## 10 (394400 4572800)   330     200.   0         0 <df [4 × 6]> <forest [4]>
## # ℹ 536 more rows

We now call again impute_forests() with this information. Unless we force it, the function will not overwrite those forest objects already present in y_2. On the other hand, we will assume that any wildland location not classified as forest or shrubland should correspond to pastures. Hence, in this case we will ask the function to make imputations in locations with missing vegetation class (missing_class_imputation = TRUE) and define a empty forest to be imputed in those (missing_class_forest = emptyforest()):

y_3 <- impute_forests(y_2, sf_fi = sf_sfi, dem = dem, 
                      forest_map = veg_map, 
                      var_class = "TEXT_HIC1",
                      missing_class_imputation = TRUE,
                      missing_class_forest = emptyforest(),
                      progress = FALSE)
## |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          |---------|---------|---------|---------|=========================================                                          
## ! 8 forest classes were not represented in forest inventory data. Geographic/topographic criteria used for 59 target locations.
##  Forest imputed on 131 out of 131 target wildland locations (100%).

We call again function check_forests() to verify that there are no wildland cells without a forest object defined:

##  No wildland locations with NULL values in column 'forest'.
##  All objects in column 'forest' have the right class.
##  No missing/wrong values detected in key tree/shrub attributes of 'forest' objects.

Structure correction

The forests resulting from imputation are formally fine for simulations, but the forest structure in the target locations can be very different than that of the forest inventory used as reference, even if the forest types are the same. Therefore, it is advisable to correct the forest structure with available information.

There are several global products made recently available, that combine satellite LiDAR observations with other information, such as Simard et al. (2011), Potapov et al. (2021) or Lang et al. (2023). Alternatively, airborne LiDAR products are available for some countries and regions. Here we will use biophysical structural maps derived from LiDAR flights in Catalonia (years 2016-2017). First we will load a mean tree height raster at 20-m resolution:

height_map <- terra::rast(paste0(dataset_path, "RemoteSensing/Sources/Catalunya/Lidar/VariablesBiofisiques/RastersComplets/2016-2017/variables-biofisiques-arbrat-v1r0-hmitjana-2016-2017.tif"))
height_map
## class       : SpatRaster 
## dimensions  : 13100, 13400, 1  (nrow, ncol, nlyr)
## resolution  : 20, 20  (x, y)
## extent      : 260000, 528000, 4488000, 4750000  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source      : variables-biofisiques-arbrat-v1r0-hmitjana-2016-2017.tif 
## name        : variables-biofisiques-arbrat-v1r0-hmitjana-2016-2017

This resolution is a bit finer than the size of forest inventory plots. Hence, we aggregate the raster to the 40m resolution, while we crop to the target area:

height_map_40 <- terra::aggregate(terra::crop(height_map, r), 
                                  fact = 2, fun = "mean", na.rm = TRUE)
height_map_40
## class       : SpatRaster 
## dimensions  : 255, 375, 1  (nrow, ncol, nlyr)
## resolution  : 40, 40  (x, y)
## extent      : 444920, 459920, 4668360, 4678560  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source(s)   : memory
## name        : variables-biofisiques-arbrat-v1r0-hmitjana-2016-2017 
## min value   :                                                3.965 
## max value   :                                               25.000

Mean tree height data has the following distribution:

names(height_map_40)<- "height"
ggplot()+
  geom_spatraster(aes(fill=height), data=height_map_40)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m", type = "viridis", na.value = NA)+
  theme_bw()

Tree height map derived from LiDAR

We now call function modify_forest_structure() to correct mean tree height according to the LiDAR data (Note the correction of units: tree heights are in cm in medfate):

height_map_40_cm <- height_map_40*100
y_4 <- modify_forest_structure(y_3, height_map_40_cm, var = "mean_tree_height",
                               progress = FALSE)

Correction of tree heights also affects tree diameters, because the function assumes that the diameter-height relationship needs to be preserved. If we inspect the same forest object again, we will be able to note changes in height and diameter values:

y_4$forest[[1]]
## $treeData
##            Species       DBH    Height          N      Z50  Z95
## 1     Quercus ilex 38.593251 1234.4853   14.14711 702.5790 5020
## 2     Quercus ilex 30.742262 1348.8405   84.88264 702.5790 5020
## 3  Quercus petraea 31.111522 1409.0589   14.14711 209.3124 1040
## 4     Quercus ilex 24.487856 1182.0479  318.30989 702.5790 5020
## 5  Quercus petraea 24.089557 1036.9594   63.66198 209.3124 1040
## 6     Quercus ilex 18.978536 1025.4046  572.95780 702.5790 5020
## 7  Quercus petraea 18.147932 1114.3324  127.32395 209.3124 1040
## 8     Quercus ilex 11.426616  733.2928 1018.59164 702.5790 5020
## 9  Quercus petraea 11.035550  748.1729  127.32395 209.3124 1040
## 10    Quercus ilex  6.234774  374.0864 1018.59164 702.5790 5020
## 11 Quercus petraea  6.234774  498.7819  127.32395 209.3124 1040
## 12  Crataegus spp.  1.870432  124.6955  318.30989 456.0124 2862
## 13    Quercus ilex  1.870432  124.6955 1273.23955 702.5790 5020
## 14 Quercus petraea  1.870432  124.6955  318.30989 209.3124 1040
## 
## $shrubData
##         Species Cover Height      Z50  Z95
## 1  Hedera helix     5    200 173.0294  812
## 2 Erica arborea     5    160 346.1416 2000
## 3 Lonicera spp.     2    150 392.2431 2353
## 4   Prunus spp.     2     50 541.3475 3577
## 
## $herbCover
## [1] NA
## 
## $herbHeight
## [1] NA
## 
## attr(,"class")
## [1] "forest" "list"

Additionally, one may have access to other maps of structural variables. In our case, we will use a raster of basal area, also derived from LiDAR flights:

basal_area_map <- terra::rast(paste0(dataset_path, "RemoteSensing/Sources/Catalunya/Lidar/VariablesBiofisiques/RastersComplets/2016-2017/variables-biofisiques-arbrat-v1r0-ab-2016-2017.tif"))
basal_area_map
## class       : SpatRaster 
## dimensions  : 13100, 13400, 1  (nrow, ncol, nlyr)
## resolution  : 20, 20  (x, y)
## extent      : 260000, 528000, 4488000, 4750000  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source      : variables-biofisiques-arbrat-v1r0-ab-2016-2017.tif 
## name        : variables-biofisiques-arbrat-v1r0-ab-2016-2017

We perform the same aggregation done for heights:

basal_area_map_40 <- terra::aggregate(terra::crop(basal_area_map, r), 
                                      fact = 2, fun = "mean", na.rm = TRUE)
basal_area_map_40
## class       : SpatRaster 
## dimensions  : 255, 375, 1  (nrow, ncol, nlyr)
## resolution  : 40, 40  (x, y)
## extent      : 444920, 459920, 4668360, 4678560  (xmin, xmax, ymin, ymax)
## coord. ref. : ETRS89 / UTM zone 31N (EPSG:25831) 
## source(s)   : memory
## name        : variables-biofisiques-arbrat-v1r0-ab-2016-2017 
## min value   :                                           3.48 
## max value   :                                          60.00

Basal area geographic distribution looks as follows:

names(basal_area_map_40)<- "basal_area"
ggplot()+
  geom_spatraster(aes(fill=basal_area), data=basal_area_map_40)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m2/ha", type = "viridis", na.value = NA, limits = c(0,70))+
  theme_bw()

Basal area map derived from LiDAR

We now use the same function to correct basal area values (no unit conversion is needed in this case):

y_5 <- modify_forest_structure(y_4, basal_area_map_40, var = "basal_area",
                               progress = FALSE)

Note that basal area (or tree density) corrections should be done after the height correction, because of the effect that height correction has on tree diameters. The correction of basal area operates on tree density values. As before, we can inspect changes in tree density:

y_5$forest[[1]]
## $treeData
##            Species       DBH    Height          N      Z50  Z95
## 1     Quercus ilex 38.593251 1234.4853   6.189625 702.5790 5020
## 2     Quercus ilex 30.742262 1348.8405  37.137749 702.5790 5020
## 3  Quercus petraea 31.111522 1409.0589   6.189625 209.3124 1040
## 4     Quercus ilex 24.487856 1182.0479 139.266560 702.5790 5020
## 5  Quercus petraea 24.089557 1036.9594  27.853312 209.3124 1040
## 6     Quercus ilex 18.978536 1025.4046 250.679808 702.5790 5020
## 7  Quercus petraea 18.147932 1114.3324  55.706624 209.3124 1040
## 8     Quercus ilex 11.426616  733.2928 445.652991 702.5790 5020
## 9  Quercus petraea 11.035550  748.1729  55.706624 209.3124 1040
## 10    Quercus ilex  6.234774  374.0864 445.652991 702.5790 5020
## 11 Quercus petraea  6.234774  498.7819  55.706624 209.3124 1040
## 12  Crataegus spp.  1.870432  124.6955 139.266560 456.0124 2862
## 13    Quercus ilex  1.870432  124.6955 557.066239 702.5790 5020
## 14 Quercus petraea  1.870432  124.6955 139.266560 209.3124 1040
## 
## $shrubData
##         Species Cover Height      Z50  Z95
## 1  Hedera helix     5    200 173.0294  812
## 2 Erica arborea     5    160 346.1416 2000
## 3 Lonicera spp.     2    150 392.2431 2353
## 4   Prunus spp.     2     50 541.3475 3577
## 
## $herbCover
## [1] NA
## 
## $herbHeight
## [1] NA
## 
## attr(,"class")
## [1] "forest" "list"

To finish this section, we will show the effect of imputation and correction on structural variables, compared with the LiDAR data.

p1 <- plot_variable(y_3, "basal_area", r = r)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m2/ha", limits = c(0,70), type = "viridis", na.value = NA)+
  labs(title = "a) Imputation")+theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
p2 <- plot_variable(y_4, "basal_area", r = r)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m2/ha", limits = c(0,70), type = "viridis", na.value = NA)+
  labs(title = "b) Imputation + H correction")+theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
p3 <- plot_variable(y_5, "basal_area", r = r)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m2/ha", limits = c(0,70), type = "viridis", na.value = NA)+
  labs(title = "c) Imputation + H/BA correction")+theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
x_vect <- terra::vect(sf::st_transform(sf::st_geometry(x), terra::crs(basal_area_map_40)))
x_vect$basal_area <- terra::extract(basal_area_map_40, x_vect)$basal_area
r_ba<-terra::rasterize(x_vect, r, field = "basal_area")
p4 <- ggplot()+
  geom_spatraster(aes(fill=last), data=r_ba)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("m2/ha", limits = c(0,70), type = "viridis", na.value = NA)+
  labs(title = "d) Basal area from LiDAR")+
  theme_bw()
cowplot::plot_grid(p1, p2, p3, p4, nrow = 4, ncol = 1)

Effect of imputation, height correction and basal area correction on basal area over the study area

where it is apparent that both the height correction and the basal area correction have an effect in basal area. Correcting only for height is not satisfactory in terms of basal area, because of the modification of diameters (without correcting density). Note that the map after the two corrections differs from the LiDAR basal area in locations that have not been corrected because of missing LiDAR values (or missing tree data). We can quantitatively assess the relationship between predicted basal area and the observed one using:

ba_5 <- extract_variables(y_5, "basal_area")$basal_area
cor.test(ba_5, x_vect$basal_area)
## 
##  Pearson's product-moment correlation
## 
## data:  ba_5 and x_vect$basal_area
## t = 90.251, df = 2047, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.8849111 0.9023312
## sample estimates:
##       cor 
## 0.8939584

We can also see the effect of the imputation and correction on mean tree height:

p1 <- plot_variable(y_3, "mean_tree_height", r = r)+
  scale_fill_continuous("cm", limits = c(0,2600), type = "viridis", na.value = NA)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  labs(title = "a) Imputation")+
  theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
p2 <- plot_variable(y_4, "mean_tree_height", r = r)+
  scale_fill_continuous("cm", limits = c(0,2600), type = "viridis", na.value = NA)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  labs(title = "b) Imputation + H mean_tree_height")+
  theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
p3 <- plot_variable(y_5, "mean_tree_height", r = r)+
  scale_fill_continuous("cm", limits = c(0,2600), type = "viridis", na.value = NA)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  labs(title = "c) Imputation + H/BA correction")+
  theme_bw()
## Scale for fill is already present.
## Adding another scale for fill, which will replace the existing scale.
x_vect <- terra::vect(sf::st_transform(sf::st_geometry(x), terra::crs(height_map_40_cm)))
x_vect$height <- terra::extract(height_map_40_cm, x_vect)$height
r_ba<-terra::rasterize(x_vect, r, field = "height")
p4 <- ggplot()+
  geom_spatraster(aes(fill=last), data=r_ba)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_continuous("cm", limits = c(0,2600), type = "viridis", na.value = NA)+
  labs(title = "d) Mean tree height from LiDAR")+
  theme_bw()
cowplot::plot_grid(p1, p2, p3, p4, nrow = 4, ncol = 1)

Effect of imputation, mean tree height correction and basal area correction on mean tree height

Here the basal area correction did not have any effect on mean tree height. The relationship between estimated and predicted mean tree height is:

mth_5 <- extract_variables(y_5, "mean_tree_height")$mean_tree_height
cor.test(mth_5, x_vect$height)
## 
##  Pearson's product-moment correlation
## 
## data:  mth_5 and x_vect$height
## t = 85.109, df = 1944, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.8781348 0.8969684
## sample estimates:
##       cor 
## 0.8879232

Finally, we check again that forests are well-defined, using function check_forests():

##  No wildland locations with NULL values in column 'forest'.
##  All objects in column 'forest' have the right class.
##  No missing/wrong values detected in key tree/shrub attributes of 'forest' objects.

Soil parameterization

Soil information is most usually lacking for the target locations. Regional maps of soil properties may be available in some cases. Here we assume this information is not available, so that we resort to global products. In particular, we will use information provided in SoilGrids at 250 m resolution (Hengl et al. (2017); Poggio et al. (2021)).

SoilGrids 2.0 data

Function add_soilgrids() can perform queries using the REST API of SoilGrids, but this becomes problematic for multiple sites. Hence, we recommend downloading SoilGrid rasters for the target region and storing them in a particular format, so that function add_soilgrids() can read them (check the details of the function documentation). The extraction of SoilGrids data for our target cells is rather fast using this approach:

soilgrids_path = paste0(dataset_path,"Soils/Sources/Global/SoilGrids/Spain/")
y_6 <- add_soilgrids(y_5, soilgrids_path = soilgrids_path, progress = FALSE)

And the result has an extra column soil:

y_6
## Simple feature collection with 2550 features and 7 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 445022.8 ymin: 4668454 xmax: 459822.8 ymax: 4678454
## Projected CRS: ETRS89 / UTM zone 31N
## # A tibble: 2,550 × 8
##              geometry    id elevation slope aspect land_cover_type
##           <POINT [m]> <int>     <dbl> <dbl>  <dbl> <chr>          
##  1 (450222.8 4678454)     1      886.  9.62   66.7 wildland       
##  2 (449422.8 4678254)     2     1000.  6.86   45.2 wildland       
##  3 (449622.8 4678254)     3      932. 32.8   134.  wildland       
##  4 (449822.8 4678254)     4      853. 20.8   164.  wildland       
##  5 (450022.8 4678254)     5      832. 22.6   154.  wildland       
##  6 (450222.8 4678254)     6      811. 29.6   137.  wildland       
##  7 (450422.8 4678254)     7      792. 30.7   195.  wildland       
##  8 (450622.8 4678254)     8      831. 21.4   146.  wildland       
##  9 (450822.8 4678254)     9      822. 27.6   234.  wildland       
## 10 (451022.8 4678254)    10      846. 28.0   185.  wildland       
## # ℹ 2,540 more rows
## # ℹ 2 more variables: forest <list>, soil <list>

The elements of the list are the usual data frames of soil properties in medfate:

y_6$soil[[1]]
##   widths clay sand   om   bd  rfc nitrogen
## 1     50 21.9 38.7 8.79 1.12 18.0     5.18
## 2    100 21.7 39.2 3.79 1.13 21.8     2.51
## 3    150 23.4 38.0 2.52 1.25 19.7     1.92
## 4    300 25.6 37.6 1.77 1.43 19.0     1.16
## 5    400 26.0 39.2 1.37 1.52 20.7     1.05
## 6   1000 25.7 38.0 0.86 1.54 21.7     0.95

During data retrieval, there might be some locations where SoilGrids 2.0 data was missing. We can use function check_soils() to detect those cases and fill them with default values:

y_7 <- check_soils(y_6, missing_action = "default")
##  71 null 'soil' elements out of 2479 wildland/agriculture locations (2.9%).
##  No wildland/agriculture locations with NULL values in column 'soil'.
##  Default 'clay' values assigned for 27 locations (1.1%).
##  Default 'sand' values assigned for 27 locations (1.1%).
##  Default 'bd' values assigned for 27 locations (1.1%).
##  Default 'rfc' values assigned for 27 locations (1.1%).

Soil depth and rock content modification

SoilGrids 2.0 does not provide information on soil depth, and rock fragment content is normally underestimated, which leads to an overestimation of water holding capacity. Function modify_soils() allows modifying soil definitions, if information is available for soil depth, depth to the (unaltered) bedrock, or both. Soil depth maps are not common in many regions, so here we will resort on a global product at 250m-resolution by Shangguan et al. (2017), which consists on three rasters:

# Censored soil depth (cm)
bdricm <- terra::rast(paste0(dataset_path, "Soils/Sources/Global/SoilDepth_Shangguan2017/BDRICM_M_250m_ll.tif"))
# Probability of bedrock within first 2m [0-100]
bdrlog <- terra::rast(paste0(dataset_path, "Soils/Sources/Global/SoilDepth_Shangguan2017/BDRLOG_M_250m_ll.tif"))
# Absolute depth to bedrock (cm)
bdticm <- terra::rast(paste0(dataset_path, "Soils/Sources/Global/SoilDepth_Shangguan2017/BDTICM_M_250m_ll.tif"))

In order to accelerate raster manipulations, we crop the global rasters to the extent of the target area:

x_vect <- terra::vect(sf::st_transform(sf::st_geometry(x), terra::crs(bdricm)))
x_ext <- terra::ext(x_vect)
bdricm <- terra::crop(bdricm, x_ext, snap = "out")
bdrlog <- terra::crop(bdrlog, x_ext, snap = "out")
bdticm <- terra::crop(bdticm, x_ext, snap = "out")

Censored soil depth is a poor product of actual soil depth, but we have observed a fairly good correlation between soil depth values in Catalonia and the probability of finding the bedrock within the first two meters. Hence, we multiply the two layers and use it as a (crude) estimate of soil depth, expressing it in mm:

soil_depth_mm <- (bdricm$BDRICM_M_250m_ll*10)*(1 - (bdrlog$BDRLOG_M_250m_ll/100))

and we take the depth to bedrock as appropriate, but change its units to mm as well:

depth_to_bedrock_mm <- bdticm*10

We can now call function modify_soils() with the two rasters to perform the correction of soil characteristics:

y_8 <- modify_soils(y_7, 
                    soil_depth_map = soil_depth_mm, 
                    depth_to_bedrock_map = depth_to_bedrock_mm,
                    progress = FALSE)

In this case, the depth to bedrock values were deeper than 2m, so that only the soil depth map had an effect on the correction procedure. After the correction, the rock fragment content of the soil has changed substantially:

y_8$soil[[1]]
##   widths clay sand   om   bd      rfc nitrogen
## 1     50 21.9 38.7 8.79 1.12 18.00000     5.18
## 2    100 21.7 39.2 3.79 1.13 21.80000     2.51
## 3    150 23.4 38.0 2.52 1.25 19.70000     1.92
## 4    300 25.6 37.6 1.77 1.43 30.89789     1.16
## 5    400 26.0 39.2 1.37 1.52 54.92958     1.05
## 6   1000 25.7 38.0 0.86 1.54 97.50000     0.95

We can compare the effect of the correction on the soil water capacity (in mm) by inspecting the following plots (note the change in magnitude and spatial pattern):

p1 <- plot_variable(y_7, "soil_vol_extract", r = r)+ 
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_distiller("mm", type = "seq", palette = "YlGnBu", direction = 1, na.value = NA)+
  labs(title="SoilGrids alone")+
  theme_bw()
p2 <- plot_variable(y_8, "soil_vol_extract", r = r)+ 
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  scale_fill_distiller("mm", type = "seq", palette = "YlGnBu", direction = 1, na.value = NA)+
  labs(title="SoilGrids + depth correction")+
  theme_bw()
cowplot::plot_grid(p1, p2, ncol =1, nrow=2)

Extractable soil water volume before and after correcting SoilGrids data

Finally, we can call again check_soils() to verify that everything is fine:

##  71 null 'soil' elements out of 2479 wildland/agriculture locations (2.9%).
##  No wildland/agriculture locations with NULL values in column 'soil'.
##  No missing values detected in key soil attributes.

Additional variables

In this section we illustrate the estimation of additional variables that are needed in some occasions. At present, there are no specific functions in medfateland for these variables.

Crop factors for agricultural areas

If there are target locations whose land cover type is agriculture we should supply a column called crop_factor in our sf input object, so that soil water balance can be conducted in agriculture locations. Crop maps for Europe can be found, for example in d’Andrimont et al. (2021). In our case we will use regional data from the Catalan administration (Mapa de cultius from 2018). We start by reading the crop map and subsetting it to the target area:

file_crop_map <- paste0(dataset_path,"Agriculture/Sources/Catalunya/Cultius_DUN2018/Cultius_DUN2018.shp")
crop_map <- sf::st_read(file_crop_map, options = "ENCODING=UTF-8")
## options:        ENCODING=UTF-8 
## Reading layer `Cultius_DUN2018' from data source 
##   `/home/miquel/OneDrive/EMF_datasets/Agriculture/Sources/Catalunya/Cultius_DUN2018/Cultius_DUN2018.shp' 
##   using driver `ESRI Shapefile'
## Simple feature collection with 638797 features and 9 fields
## Geometry type: MULTIPOLYGON
## Dimension:     XY
## Bounding box:  xmin: 264864.2 ymin: 4488884 xmax: 523857.3 ymax: 4733681
## Projected CRS: ETRS89 / UTM zone 31N
crop_map <- terra::crop(terra::vect(crop_map[,"Cultiu"]), r)

Crops in the target watershed, occupy valley bottoms as expected:

ggplot()+
  geom_spatvector(aes(fill=Cultiu), data=crop_map)+
  geom_spatvector(fill = NA, col = "black", linewidth = 0.5, data = watershed)+
  theme_bw()+theme(legend.position = "none")

Crop distribution in the study area

To obtain our crop factors, we first extract the crop name corresponding to agriculture locations:

sel_agr <- y_1$land_cover_type=="agriculture"
x_agr <- sf::st_transform(sf::st_geometry(x)[sel_agr], terra::crs(crop_map))
x_agr_crop <- terra::extract(crop_map, 
                             terra::vect(x_agr))

Some cells may have missing values, specially if the land cover map and the crop map are not consistent:

df_agr_crop <- as.data.frame(x_agr_crop)
table(is.na(df_agr_crop$Cultiu))
## 
## FALSE  TRUE 
##   196   131

For simplicity we will assume the missing values correspond to Ray-grass, the most common crop in the area:

df_agr_crop$Cultiu[is.na(df_agr_crop$Cultiu)] <- "RAY-GRASS"

In order to transform crop names into crop factors, we need a look-up table, which we prepared for Catalonia

crop_lookup_table <- readxl::read_xlsx(paste0(dataset_path, "Agriculture/Sources/Catalunya/Kc_CAT_MOD.xlsx"))
head(crop_lookup_table)
## # A tibble: 6 × 5
##   Cultiu_map                  Cultiu_text                 Grup   Asignacio    Kc
##   <chr>                       <chr>                       <chr>  <chr>     <dbl>
## 1 ALBERCOQUERS                Albercoquer                 FUITA… Albercoq… 0.383
## 2 ALBERGÍNIA                  Alberginia                  HORTÍ… Albergin… 0.226
## 3 ALFÀBREGA                   Alfabrega                   ALTRE… Alfabrega 0.1  
## 4 ALFALS NO SIE               Alfals no siega             FARRA… Alfals    0.78 
## 5 ALFALS SIE                  Alfals siega                FARRA… Alfals    0.78 
## 6 ALGARROBA HERBACIA NO SIEGA Algarroba herbacia no siega LLEGU… Mitjana … 0.36

We join the two tables by the crop name column and get the crop factor (column Kc):

df_agr_crop <- df_agr_crop |>
  left_join(crop_lookup_table, by=c("Cultiu"="Cultiu_map"))
y_8$crop_factor <- NA
y_8$crop_factor[sel_agr] <- df_agr_crop$Kc
summary(y_8$crop_factor[sel_agr])
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##  0.1725  0.5212  1.0000  0.7965  1.0000  1.0000

Hydrogeology

Watershed simulations with watershed_model = "tetis" require defining spatial variables necessary for the simulation of groundwater flows and aquifer dynamics:

  • Depth to bedrock [depth_to_bedrock] - Depth to unweathered bedrock, in mm.
  • Bedrock hydraulic conductivity [bedrock_conductivity] - Hydraulic conductivity of the bedrock, in m·day-1.
  • Bedrock porosity [bedrock_porosity] - Bedrock porosity (as proportion of volume).

As estimate of depth to bedrock, one can use the same variable from Shangguan et al. (2017), that we already transformed to mm:

x_vect <- terra::vect(sf::st_transform(sf::st_geometry(y_8), 
                                       terra::crs(depth_to_bedrock_mm)))
y_8$depth_to_bedrock <-terra::extract(depth_to_bedrock_mm, x_vect)[,2, drop = TRUE]

which we can plot using:

Depth to bedrock from GLHYMPS 2.0

If regional maps are not available to inform about permeability and conductivity, we suggest using the GLobal HYdrogeology MaPS, GLHYMPS 2.0 (Huscroft et al. 2021):

glhymps_map <- terra::vect(paste0(dataset_path,"Soils/Sources/Global/GLHYMPS2/GLHYMPS_Spain.shp"))
glhymps_map
##  class       : SpatVector 
##  geometry    : polygons 
##  dimensions  : 18954, 23  (geometries, attributes)
##  extent      : -556597.5, 445486.2, 3637705, 4410471  (xmin, xmax, ymin, ymax)
##  source      : GLHYMPS_Spain.shp
##  coord. ref. : Cylindrical_Equal_Area 
##  names       : OBJECTID_1 IDENTITY_ logK_Ice_x logK_Ferr_ Porosity_x K_stdev_x1
##  type        :      <int>     <chr>      <int>      <int>      <int>      <int>
##  values      :     943032   ESP3276      -1520      -1520         19        250
##                    943035   ESP3282      -1180      -1180          6        150
##                    943042   ESP3291      -1180      -1180          6        150
##  OBJECTID Descriptio    XX    YY (and 13 more)
##     <int>      <chr> <chr> <chr>              
##         0         NA    NA    NA              
##         0         NA    NA    NA              
##         0         NA    NA    NA

We first extract the GLHYMPS 2.0 data on the target locations:

x_vect <- terra::vect(sf::st_transform(sf::st_geometry(y_8), 
                                       terra::crs(glhymps_map)))
x_glhymps <- terra::extract(glhymps_map, x_vect)
head(x_glhymps)
##   id.y OBJECTID_1 IDENTITY_ logK_Ice_x logK_Ferr_ Porosity_x K_stdev_x1
## 1    1    1194174   ESP3435      -1520      -1520         19        250
## 2    2    1194174   ESP3435      -1520      -1520         19        250
## 3    3    1194174   ESP3435      -1520      -1520         19        250
## 4    4    1194174   ESP3435      -1520      -1520         19        250
## 5    5    1194174   ESP3435      -1520      -1520         19        250
## 6    6    1194174   ESP3435      -1520      -1520         19        250
##   OBJECTID Descriptio   XX   YY   ZZ   AA   DD Shape_Leng GUM_K Prmfrst
## 1        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
## 2        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
## 3        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
## 4        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
## 5        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
## 6        0       <NA> <NA> <NA> <NA> <NA> <NA>          0     1       0
##   Shape_Le_1 Shape_Area Transmissi COUNT AREA_1 MEAN STD
## 1     939134 1701770734          0     0      0    0   0
## 2     939134 1701770734          0     0      0    0   0
## 3     939134 1701770734          0     0      0    0   0
## 4     939134 1701770734          0     0      0    0   0
## 5     939134 1701770734          0     0      0    0   0
## 6     939134 1701770734          0     0      0    0   0

For porosity we simply divide the GLHYMPS 2.0 value by 100 to find the proportion:

y_8$bedrock_porosity <- x_glhymps[,"Porosity_x", drop = TRUE]/100

Its geographic distribution is quite simple:

plot_variable(y_8, "bedrock_porosity", r = r)

Bedrock porosity from GLHYMPS 2.0

GLHYMPS 2.0 provides permeability in the log scale, and the following operations are needed to obtain hydraulic conductivity in m/day:

# Permeability m2
k <- 10^(x_glhymps[,"logK_Ferr_", drop = TRUE]/100)
# Water density kg·m-3
rho <- 999.97 
# Gravity m·s-2
g <- 9.8
# Viscosity of water
mu <- 1e-3
# Conductivity m/s
K <- k*rho*g/mu
# Daily conductivity m/day
K_day <- K*3600*24

Finally, we assign the conductivity values to the sf object:

y_8$bedrock_conductivity <- K_day

Its geographic distribution is very simple, again:

plot_variable(y_8, "bedrock_conductivity", r = r)

Bedrock conductivity from GLHYMPS 2.0

Other variables

Simulation of management scenarios requires defining additional variables in the sf object, concerning the area represented by each location and the management unit to which it belongs. This is illustrated in vignette Management scenarios.

Storing

At the end of the process of building spatial inputs, we should store the result as an RDS file, to be loaded at the time of performing simulations, e.g.

saveRDS(y_8, "bianya.rds")

Since the data set corresponds to a watershed, we should also store the raster:

r$value <- TRUE
terra::writeRaster(r, "bianya_raster.tif", overwrite=TRUE)

Initialization test

We can check whether the input data set is well formed by calling function initialize_landscape():

z <- initialize_landscape(y_8, SpParamsMED, defaultControl(),
                          progress = FALSE)