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Get lake catchments based on intersection points between stream network and lakes

Source: R/get_lake_catchment.R
get_lake_catchment.Rd

Delineate lake catchments in GeoTIFF format based on intersection points between stream network (i.e. Hydrography90m) and lake geospatial files (e.g. HydroLAKES). The function uses the lake intersection tables from get_lake_intersection.R as input data.

Usage

get_lake_catchment(
  data,
  flow = "flow_accu_mean",
  lake_id = "lake_ID",
  n = "all",
  direction,
  lake_basin,
  n_cores = 1,
  quiet = TRUE
)

Arguments

data

a data.frame or data.table that contains the columns regarding the stream segment ids of the intersection points between lake and stream network; (i.e., output of get_lake_intersection)

flow

character. The name of the flow accumulation column used for sorting the intersection table; i.e. either flow_accu (flow accumulation value at intersection point pixel), flow_accu_max (maximum flow accumulation value of 3 x 3 neighboring pixels),

lake_id

character. The name of the column containing lake ids; (i.e., output "lake_ID" of get_lake_intersection) flow_accu_mean (mean flow accumulation value of 3 x 3 neighboring pixels). Default is flow_accu_mean

n

integer. Number of intersection points used for lake catchment delineation; e.g. n=1 equals first row of intersection table and lake outlet; n=20 equals first 20 rows of intersection table; Default is all.

direction

character. Full path to Hydrography90m flow direction tif file

lake_basin

character. Full path to output catchment tif files

n_cores

integer. Number of cores used in parallelization; Default is one.

quiet

logical. If FALSE, the standard output will be printed.; Default is TRUE.

Note

For the function to work we need the output of the function get_lake_intersection that are the lake_referenceID.txt and intersection table (i.e. coord_lakeID.txt)

References

add reference manual html here https://grass.osgeo.org/grass82/manuals/

Author

Jaime Garcia Marquez, Thomas Tomiczek

Examples

# Download test data into the temporary R folder
# or define a different directory
my_directory <- tempdir()
download_test_data(my_directory)

data <- fread(paste0(my_directory,
                       "/hydrography90m_test_data",
                       "/coord_lake_1.txt"),
                      header = TRUE)

direction <- (paste0(my_directory,
                    "/hydrography90m_test_data",
                  "/direction_1264942.tif"))

catch <- (paste0(my_directory,
                   "/hydrography90m_test_data/"))

get_lake_catchment(data, direction = direction, lake_basin = catch)