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landuse.lum

Purpose

landuse.lum is the master table of land use and management classes. Each row defines one class by name and lists string pointers to records in other files: the plant community (plants.ini), management schedule (management.sch), curve number entry (cntable.lum), conservation practice (cons_practice.lum), urban land use (urban.urb), overland-flow Manning's n class (ovn_table.lum), tile drainage (tiledrain.str), septic (septic.str), filter strip (filterstrip.str), grassed waterway (grassedww.str), and user BMP (bmpuser.str). HRUs reference a row in this table through hru-data.hru. After reading, the reader resolves every non-null string pointer to an integer index stored in lum_str; unresolved names are logged to simulation.out (unit 9001).

Source

Format

  • Line 1: title (skipped).
  • Line 2: header (skipped).
  • One record per land use class. Records are list-directed (free format). All 14 fields are read on every row.
  • Any pointer field that should be empty must be the literal string null. The reader treats null as "no link" and does not try to resolve it.
# Field Type Default Description
1 name char(40) blank name of the land use and management class. Referenced from hru-data.hru
2 cal_group char(40) blank calibration group label. Not currently used by the solver
3 plant_cov char(40) blank plant community pointer into plants.ini. Resolved to lum_str%plant_cov
4 mgt_ops char(40) blank management schedule pointer into management.sch. Resolved to lum_str%mgt_ops
5 cn_lu char(40) blank curve number entry pointer into cntable.lum. Resolved to lum_str%cn_lu
6 cons_prac char(40) blank conservation practice pointer into cons_practice.lum. Resolved to lum_str%cons_prac
7 urb_lu char(40) blank urban land use pointer into urban.urb (e.g. URLD, URHD). Resolved during urban init
8 urb_ro char(40) blank urban runoff model. usgs_reg for USGS regression equations, buildup_washoff for build-up/wash-off
9 ovn char(40) blank overland-flow Manning's n class pointer into ovn_table.lum
10 tiledrain char(40) blank tile drainage pointer into tiledrain.str. Resolved to lum_str%tiledrain
11 septic char(40) blank septic pointer into septic.str. Resolved to lum_str%septic
12 fstrip char(40) blank filter strip pointer into filterstrip.str. Resolved to lum_str%fstrip
13 grassww char(40) blank grassed waterway pointer into grassedww.str. Resolved to lum_str%grassww
14 bmpuser char(40) blank user-defined BMP pointer into bmpuser.str. Resolved to lum_str%bmpuser

The reader logs a line to simulation.out for every non-null pointer that fails to match a name in the target file. The simulation continues with the link unresolved (index zero), which means the corresponding behaviour is skipped.

Example

Excerpt from refdata/Ames_sub1/landuse.lum:

landuse.lum: written by SWAT+ editor v2.3.3 on 2023-10-25 08:58 for SWAT+ rev.60.5.7
name                         cal_group          plnt_com                                        mgt               cn2         cons_prac             urban            urb_ro           ov_mann              tile               sep               vfs              grww               bmp
cosy_lum                          null         cosy_comm                                     mgt_01        rc_strow_g     up_down_slope              null              null    convtill_nores              null              null              null              null              null
agrr_lum                          null         agrr_comm                                   AGRR_rot        rc_strow_g       cross_slope              null              null      convtill_res              null              null              null              null              null
frst_lum                          null         frst_comm                                       null            wood_f     up_down_slope              null              null        forest_med              null              null              null              null              null
urld_lum                          null              null                                       null             urban     up_down_slope              URLD   buildup_washoff     urban_asphalt              null              null              null              null              null

Notes:

  • The header tokens written by SWAT+ Editor (plnt_com, cn2, urban, ov_mann, tile, sep, vfs, grww, bmp) do not match the field names in the source (plant_cov, cn_lu, urb_lu, ovn, tiledrain, septic, fstrip, grassww, bmpuser). The reader skips the header and uses position only.
  • urld_lum is an urban class. Its plant_cov and mgt_ops are both null; the row links instead to URLD in urban.urb and selects buildup_washoff as the urban runoff model.
  • frst_lum has no management schedule (mgt_ops = null). Forest classes typically rely on the plant community initialization alone.
  • hru-data.hru. Each HRU points to one landuse.lum row by name.
  • cntable.lum. Curve number table referenced by the cn_lu field. Each row holds a name and four curve numbers (hydrologic conditions A through D).
  • cons_practice.lum. Conservation practice table referenced by cons_prac. Holds USLE P factor and maximum slope length per practice.
  • ovn_table.lum. Overland-flow Manning's n table referenced by ovn. Holds mean, minimum, and maximum n per class.
  • plants.ini. Target of plant_cov.
  • management.sch. Target of mgt_ops.
  • urban.urb. Target of urb_lu.
  • tiledrain.str, septic.str, filterstrip.str, grassedww.str, bmpuser.str. Structural BMP files targeted by the last five pointer columns.