3 Our Methods

3.1 GIS Analysis Requirements

This tutorial uses ESRI ArcGIS Pro (2.9). If using ArcGIS Pro, ensure your Spatial Analyst Extension is enabled. If you are unsure if this is enabled, you can check by going to Settings, Licensing, and ESRI Extensions. Once in the ESRI Extensions box, scroll down to Spatial Analyst. You will see if the license is active or “grayed out” (indicating you need to activate the Spatial Analyst License).

Additionally, you will need Microsoft Excel (2022) and a reliable internet connection to download the LANDFIRE datasets pertinent to this analysis.

Lastly, prior to beginning this analysis, we recommend that you create a new ArcGIS Pro project with a project specific geodatabase (named to your choosing!) If you are following the Ataya Study Area tutorial, please save that Study Area shapefile to your geodatabase. You’ll be able to acquire an Ataya shapefile at the end of this section. Alternatively, if you are using your own Study Area shapefile, save it to your project specific geodatabase as you follow along with this tutorial.

3.2 Methods

Each subsequent chapter outlines steps to complete a different component of the GIS analysis. The general components of the analysis are:

  • Downloading and preparing the necessary LANDFIRE datasets for a Study Area.
  • Spatially combining these LANDFIRE datasets into one (1) new Study Area LANDFIRE dataset.
  • Performing “Join Fields” to update the new Study Area Landfire dataset.
  • Assessing acreage of the Study Area LANDFIRE dataset and “masking” it to the Study Area boundary.
  • Performing data summary Excel steps to observe acreage of: historic ecosystems, current vegetation types, ecosystem conversion, and succession classes within the Study Area.

3.3 Disclaimers

There are always many different ways to complete a GIS analysis and because of this, we’d like to share a few disclaimers.

First, this tutorial is specific to the Ataya Study Area and outlines steps exactly performed to this Study Area. If you are using a different Study Area, you will have to locate the relevant LANDFIRE datasets and Biophysical Settings (BpS) descriptions for your Study Area through the LANDFIRE website.

Second, LANDFIRE data is best represented at coarse landscape scales (i.e. landscapes in excess of 100,000 acres or more). LANDFIRE data is not as accurate for fine landscape level assessments (i.e. a forest stand of 100 acres or less). Due to the development of LANDFIRE data at large landscape scales, some LANDFIRE ecosystem data, such as Existing Vegetation Type (EVT), may not represent a 1:1 relation of the GIS data to current ground conditions. We like to think of our analysis as a guide for understanding forest conditions past and present. This guide still functions best with human input on the ground to make effective final forest management decisions. If you have smaller acreage of forest land and still wish to perform this analysis, consider using the watershed your forest is in!

Third, this tutorial GIS analysis was performed using ArcGIS Pro only. Unfortunately for managers who are using older versions of ArcMap or open source GIS/data processing software (i.e. GRASS GIS, QGIS) this tutorial is not designed for these GIS platforms. These platforms can likely recreate the outcomes of this tutorial, however specific geoprocessing tools may look or act differently. If using software other than ArcGIS Pro, make sure to understand the underlying process behind each tool.

If you are having trouble with this tutorial, here are some people that can assist you!

We are always looking for ways to improve our GIS analysis steps, accessibility of our content, and availability of this analysis to as many forest managers as possible. If you have any suggestions for us, please reach out to Keith Phelps (), Stacey Marion (), or Randy Swaty ().

3.4 Lastly… Download this!

To work through this guide you will need to download this zipped folder by clicking the hyperlinked text, then the “Download” button that will be on the right side of the screen. This folder contains:

  • An Ataya shapefile
  • An Excel file
  • One ecosystem description
  • An ArcPro map package file in case you want to explore in ArcPro.

3.5 About this document

It was written in R using R-Studio, the “bookdown” package and is hosted on GitHub(links to this repository).