GRID NAME: CONDITION and CONDITIONNO

CONDITION/CONDITIONNO represents the structural condition of vegetation for cover types that undergo succession. Each site (cell) is classified into structural stages based on its age and cover, according to a lookup table. Note, some cover types (roads, barren, water, mountain grassland, riparian, greasewood, sparse pinyon-juniper, agriculture and urban) do not have multiple structural stages and are given a value of 0. CONDITION includes roads while CONDITIONNO does not.

REQUIREMENT: Required

DERIVED FROM:

AGE, AGENO, COVER, COVERNO, RANDOMZONE and ELEVATION grids (all of these grids are created by us using other processes discussed in this document).

PROCESS USED TO CREATE:

The first step creates a grid of random numbers (0 to 1 out to four decimal places) for each COVER patch using a zonalmajority function (randomzone.aml). Once this is run, conditionsj.aml takes data from the grids AGENO, RANDOMZONE, ELEVATION and COVERNO to assign a condition class to each vegetation patch based on the probability matrices embedded in the aml. Essentially, each vegetation patch is assigned a condition class based on its age and the user-specified cover type model. The cover type model specifies the age ranges for each condition class. Note, because the age ranges are not mutually exclusive among condition classes (i.e., they overlap), it is necessary in some cases to randomly assign patches to a condition class based on the user-specified probability that a patch of a certain age will be in each condition class. This aml creates the grids CONDITON and CONDITIONNO.

ATTRIBUTES:

      Description                                                     Value

      non-vegetated and non-seral cover types        0

      stand initiation                                                1

      stem exclusion                                                2

      understory reinitiation                                    3

      shifting mosaic                                               4

      fire-maintained open canopy                          5

      early grass - forb                                             6

      mid grass - shrub                                            7

      shrub - grass                                                   8

      herb - annual                                                   9

      herb - perennial                                              10

      herb - shrub - tree                                           11

      herb-dominated                                              12

      herbs - shrubs                                                 13

      shrubs - trees                                                  14

      tree-dominated                                                15

      early shrub-dominated                                    16

      late shrub-dominated                                      17

      shrubs - herbs                                                 18

*Note, all condition classes do not exist for each cover type. Rather, each cover type has a user-specified limited set of condition classes (usually <6). The list above includes all condition classes specified across all cover types.

RMLANDS SIGNIFICANCE:

CONDITION (and CONDITIONNO) effects succession, wildfire mortality, insect and pathogen mortality and anthropogenic disturbances.

AMLS USED:

randomzone.aml and condition.aml

NOTES:

The 2002 fires (e.g., Burn Canyon) were incorporated into the process from the beginning since the AGE grid reflects these events.