Standard Operating Procedures - Transect Vegetation Quadrats

KEY DETAILS

Principal Investigator
Dr. Matthew Rogan
Date
7 July 2025
Version
1.0.0
Programme
Rangelands Biodiversity Programme
Key partners
University of Oxford; University of Liverpool
Contact email
mrogan@naturalstate.org

1. PREAMBLE

Natural State’s research methods and activities are detailed by a set of accepted Standard Operating Procedures (SOPs). These documents describe the steps involved in all Natural State research methodologies, from data collection to data processing and storage. Each SOP documents key methodological details for a specific data type. The objectives and background of the projects or surveys these methods are used for, features of the study area where these methods are applied, and details on survey and sampling designs for these methods may be found in survey Design Documents (DDs), which are available in the Related Documents section below or may be perused in the main NS Design Documents documentation page.

2. GLOSSARY

Natural State Glossary

3. METHODS OVERVIEW

3.1 METHOD AIMS

The Vegetation Transect protocol is designed to:

  1. Record the presence of grass and forb species.
  2. Produce standardized species richness and composition data across sites.
  3. Assess dung coverage as a proxy for herbivore activity.
  4. Record presence of termite activity and estimate canopy cover.
  5. Identify and count woody seedlings within each quadrat.
  6. Estimate ground cover characteristics.

3.2 METHODOLOGICAL BACKGROUND

Seasonally productive grasses and forbs play vital ecological roles in tropical savannas. Grasses, often dominant, contribute to soil stabilization, carbon sequestration, and provide critical forage for livestock and wildlife. Forbs, the herbaceous non-grass species, add to biodiversity, enhance soil fertility, and support pollinators and other fauna. The balance between grasses, forbs and woody vegetation reflects ecosystem health and can indicate overgrazing or shifts in land use. Quadrats are a widely used method in ecological studies for sampling vegetation diversity. They involve placing a square frame of known size (e.g., 1 sq. m) at random or systematic locations within a study area to record the species present and estimate their abundance. This method provides a standardized, repeatable way to assess plant composition and cover, as well as other aspects of ground and canopy cover, making it especially useful for monitoring changes in rangelands over time. Sampling with quadrats helps land managers make informed decisions to maintain or restore rangeland function and biodiversity.

This protocol requires the establishment two 1 m X 50 m transects. It involves placing quadrats at 5 m intervals along each transect for a total of 20 quadrats. Each quadrat is assessed for a consistent set of ecological indicators related to grass and forb diversity, herbivory, ground cover, etc.

4. SAMPLING PREPARATION

The equipment mentioned in the list below needs to be gathered, checked and packed before sampling begins. If any sensors need to be configured prior to commencing sampling this will be documented below the equipment list.

Note that this protocol requires a fully trained botanist with advanced knowledge of local flora. If no botanist is available, the work should not be carried out.

4.1 EQUIPMENT LIST

  • 1 sq. m metal quadrat frame
  • 50 m measuring tape
  • Densiometer
  • Gloves
  • Dustpan and brush
  • Small rake (optional)
  • Tablet or phone
  • Handheld GPS (optional)

4.2 DEVICE CONFIGURATION

The S123 app needs to be loaded onto the tablet/phone and the Transect Survey needs to be loaded. Station locations need to be loaded onto the handheld GPS.

5. SAMPLING PROCEDURES

Ensure proper setup of the sampling area.

  1. Establish a straight 50-meter transect using a measuring tape along the southern edge of the plot, running from corner 1 to corner 2.
  2. Once the tape is in place, position a 1 m² quadrat at the 0-meter mark at corner 1.
  3. Additional quadrats should then be placed every 5 meters along the transect, resulting in quadrats at 0, 5, 10, 15, 20, 25, 30, 35, 40, and 45 meters. Repeat this process along a second 50-meter transect placed along the northern edge of the plot, from corner 3 to corner 4. This results in a total of 20 quadrats (10 per transect) assessed in each plot.

5.1 Quadrat Observations

Move along each quadrat stopping at 5 m intervals to place the square quadrat frame along the inner edge of the plot and record all details of that quadrat in S123.

Begin with grass and forb species composition. At each quadrat, the field team and botanist must work together to identify all grass and forb species present. Record only presence/absence for each species (do not estimate abundance or percent cover). As each species is identified, clearly state the name out loud and confirm that the scribe has recorded it correctly before moving on. Conduct a thorough inspection of the entire quadrat, including under litter, between grass tussocks, and around rocks or woody debris, to ensure that less obvious or smaller species are not overlooked. This process should be systematic and consistent across all quadrats.

Any plant species that is not present on the existing species list, should be recorded as ‘Other’ and the species name should be written manually if known. The botanist must review the tablet to ensure spelling is correct. If the species is not known, it should also be recorded as ‘Other’, and an identifier should be recorded instead of the taxonomical name (e.g. species2_plotx). A sample of any unidentified species should be collected for identification, and a comment should be made on the form.

After recording both grass and forb species composition, continue with collection of all ancillary data on the quadrat:

  • Count and record the number of individual woody seedlings with a stem diameter of less than 2 cm, of species capable of reaching a mature height >2 m.
  • For each distinct source of dung (elephant, rhino, cow, other), estimate the approximate proportion of aereal cover for that dung source. Estimates must be recorded as a percentage from 0 (no dung) to 100 (the entire quadrat is filled with dung). It is important to briefly sweep through the vegetation and grass to ensure you haven’t missed any pieces under vegetation.
  • Record the presence or absence of termite sheeting (i.e., soil visibly worked by termites).
  • Record the woody canopy cover using a densiometer. Hold densiometer at elbow height in the center of the quadrat, making sure the bubble is centered and elbows are at 90° from the body. Count the number of open (unshaded) points out of 96 visible on the mirror grid and record the count in S123.
  • Record whether you observe any evidence of recent grazing within the quadrat such as bite marks or clipped grass.
  • Record the percentange of bare ground that is visible while looking down at the quadrat, from 0 (no bare ground is visible) to 100 (the entire quadrat is visible).
  • Record the percentage of the quadrat that is covered by rocks, regardless of size.
  • Estimate the percentage of the quadrat that is covered by woody stems and record in S123.

6. POST PROCESSING

This section details all steps that need to be followed after returning to the office from the field to ensure that samples are properly processed and stored and that data is uploaded and saved to the correct location.

6.1 SAMPLE PROCESSING AND STORAGE

Any plant species that did not previously exist in the species list, and was added as ‘Other’ should be sent to the Herbarium for identification. In cases of a species not occurring in the choices list, notify the PI and the junior data scientist.

6.2 DATA ENTRY AND UPLOADS

S123 forms need to be sent to the cloud upon return to internet or mobile phone reception. The data need to be viewed in S123 for any potential errors.

7.1 DESIGN DOCUMENTS

DD - Carbon Pool Plots

7.2 OTHER RELEVANT SOPS

==XXX==

7.3 DATA ELEMENTS

Data Collection

8. REVISION AND VERSION HISTORY AND DESCRIPTION

1.0.0 Initial SOP from July 2025.