Step 2: Set the study area and reporting units; develop monitoring objectives
Step 2a: Set the study area, reporting units, define the target population, document the geospatial layers used to describe these areas, and select the existing sample designs to be used for revisits
- First, identify the study area (e.g., field office), or geographic extent of the resource (e.g., vegetation, animals, streams) you want to report on (e.g., grazing allotment, watershed, field office, district, state). The study area should include the entire landscape area or extent of the resource that you plan to monitor to meet your management goals.
- Next, determine the desired reporting units (e.g., grazing allotment, watershed, field office, district, state). Reporting units are the geographic areas for which indicator averages and error estimates will be computed and thus minimal sample sizes are required. Reporting units are typically nested within the study area, but depending on the management goals, the reporting unit and the study area can be the same. Generally, reporting units are administrative areas where AIM data need to be summarized for a particular analysis. In contrast to strata reporting units can be defined at any point during an AIM project life cycle and do not affect how AIM data is collected. The number of acres (terrestrial) or stream kilometers (lotic) in each of the reporting units are documented in step 3.
- Define your target population. The target population (or sample frame) refers to the overall resource being monitored, and sample points are selected from within the target population. The definition of the target population should contain specific information about the resource of interest: its spatial extent, ownership status, and size (e.g. all streams or just first order streams?). Examples of the target population include: all BLM lands within a reporting unit, all perennial, wadeable streams on BLM land, and sage grouse habitat on BLM lands. (Monitoring Resources, 2017).
- Once your study area, reporting units, and target population are established, document the geospatial layers used to delineate these polygons. Information about the number of acres (terrestrial) or stream kilometers (lotic) in the study area will be added in step 3.
- Lastly, when documenting a revisit design, select the sample designs and document the geospatial layers used to generate the monitoring locations which you plan to revisit, these may include probabilistic and targeted designs. Describe which sampled points you wish to revisit and review any rejected plots that may be suitable for revisits. Should those still be rejected or included in your revisit design?
Step 2b: Develop monitoring objectives related to resource condition and resource trend
- During this step, you will fill out either the Resource Condition and Trend Objectives Tables or the Monitoring Objectives Worksheet in the terrestrial and lotic benchmarks tools. Instructions on how to fill out the Monitoring Objectives tables in the benchmark tools can be found in the benchmark tools themselves.
- Identifying and documenting clear monitoring objectives is extremely important preparation for the design phase of an AIM monitoring effort. Objectives guide how and where to focus sampling efforts so that there is sufficient data to address your management goals.
- Objectives are also necessary for the data analysis phase of an AIM monitoring effort. Monitoring objectives must be identified before any data analysis can take place.
- Begin by listing your management goals in Column 1 of the Resource Condition and Trend Objectives Tables. As you fill out the table each management goal should have one or more corresponding monitoring objectives. Lotic projects with differing objectives among reporting units will need to complete separate Resource Condition and Trend Objectives Tables for each reporting unit (see step 2a).
- Monitoring objectives are quantitative statements that provide a means of evaluating whether management goals were achieved. Monitoring objectives should be specific, quantifiable, and attainable based on ecosystem potential, as well as resource availability, and the sensitivity of the methods. Quantitative monitoring objectives may be available in your resource management plans (e.g., for sage grouse, Clean Water Act requirements) or they may be developed in the monitoring planning process.
- At a minimum, monitoring objectives should include: 1. the indicator(s) that will be monitored; 2. quantitative benchmark(s) for each indicator (read more about benchmarks); and 3. if you seek to make inference beyond the plot or reach-scale, the proportion of the resource that is required to meet the benchmark. The most robust monitoring objectives also clearly identify the reporting units, a time frame for evaluating the indicator(s), and the desired confidence level (e.g., 90% confidence) in the objective.
- Resource trend objectives are used to describe the desired change in indicator values over a specified time period. These may include short–term objectives (e.g. evaluating recovery of a study area following a disturbance) or long–term objectives. At a minimum, select an indicator(s) and the related measurement units for each management goal, the desired direction of change (upward, downward, or no change), and the time period for assessing change. The time period for assessing change could be the amount of time following or preceding a particular event (e.g. change in management or a disturbance); a comparison between two time periods (e.g. 2015-2019 compared to 2020-2024), or a fixed interval (e.g. trend over the next 10 years). For robust trend analyses it is beneficial to specify the magnitude of desired change – this is equivalent to a benchmark for trend and is the specific amount or range that the indicator should change in order to meet your objective.
- The interdisciplinary team should document benchmarks, benchmarks sources, and the proportion of the resource that is required to meet the benchmarks for each indicator of interest in columns 3-5 of the Resource Condition and Trend Objectives Tables. This exercise will quickly reveal indicators for which you will need to seek professional judgement, the development of ecological site descriptions, or other resources to aid in future data interpretation.
- For more information, see the webpage on benchmarks.
- Example monitoring objectives for condition:
- Terrestrial:
- Management goal: Ensure achievement of land health standards for threatened and endangered (T/E) species; maintain sage grouse habitat according to the habitat standards as described in the Resource Management Plan.
- Monitoring objective: Determine whether sagebrush cover of 15% or greater is maintained across 70% of the Resource Management Planning area with 80% confidence.
- Terrestrial:
- Lotic:
- Management goal: Manage streams and rivers using the sustained yield principle and in compliance with Federal Land Policy and Management Act and the Clean Water Act.
- Monitoring objective: Determine whether salinity levels are at or below 300 µS/cm in 90% of perennial wadeable stream miles in the Resource Management Planning area, over a 2 year period, with 80% confidence.
- Example monitoring objectives for trend:
- Terrestrial
- Management goal: Ensure achievement of land health standards for threatened and endangered (T/E) species; maintain sage grouse habitat according to the habitat standards as described in the Resource Management Plan.
- Monitoring objective: Determine whether sagebrush cover has increased by 10% 5 years following seeding treatment.
- Lotic:
- Management goal: Manage streams and rivers using the sustained yield principle and in compliance with Federal Land Policy and Management Act and the Clean Water Act.
- Monitoring objective: Determine whether average salinity levels have decreased by 50 µS/cm in the Resource Management Planning area from 2011 to 2020.
- Terrestrial
- More guidance on selecting indicators and setting benchmarks can be found in Technical Note 453: Guide to Using AIM and LMF data in Land Health Evaluations and Authorizations of Permitted Uses
Step 2 Example: Study Area, Reporting Units, and Monitoring Objectives
Step 2: Set the study area and reporting units; develop monitoring objectives.
Step 2a: Set the study area and reporting units
The study area for both lotic and terrestrial monitoring efforts is all BLM lands and perennial streams and rivers within the West Desert District boundary (Figure 1). The target population for terrestrial monitoring includes accessible BLM terrestrial ecosystems as defined by the national Surface Management Agency layer and verified in the field. The target population for lotic ecosystems includes streams and rivers defined as perennial by the medium resolution NHD that are verified in the field to have water at a minimum of 5 transects. Reporting units for this monitoring effort tie back to the monitoring objectives and include: the Field Office areas and sage grouse habitat areas (PHMA and GHMA). If designs stratified simply by field office do not produce enough sample points to report on sage grouse habitat, we may intensify monitoring efforts in those areas.
The geospatial data layers used to define the study area and reporting units included:
- BLM field office boundaries
- BLM land ownership: Surface Management Agency (SMA) layer published July 2015
- Sage Grouse Habitat Info: PHMA, GHMA, Focal Areas and Population Areas
- National Hydrography Dataset (NHD): medium resolution version 2.0
Step 2b: develop monitoring objectives
Monitoring objectives were identified by adding quantitative benchmarks associated with the terrestrial and lotic indicators that are related to each management goal (i.e. Terrestrial and Lotic Indicator Tables). These benchmarks communicate the indicator values that must be achieved across a specific percentage of the landscape/resource to show that conditions are acceptable (meeting objectives) vs. unacceptable (not meeting objectives). For example, the first monitoring objective in table shows that soil aggregate stability should be greater than 4 across 70% of the landscape in order for the management goal to be achieved. Unacceptable conditions could trigger a change in management. Benchmark values were gleaned from policy, research, and professional judgment.
Helpful Documents and Links
Benchmarks – From Information to Action: Monitoring Objectives, Benchmarks and Required Proportions