General Actions:
The following protocol document provides a brief summary of the collection process for FPC field data according to the method developed by the Queensland Department of Environment and Resource Management (DERM). This information is largely taken from the ABARES ground cover monitoring field manual (Muir et al. 2011) and further information on the methodology can be obtained from that source downloadable from the ABARES website. Also provided below are the links to documents for recording the collected data.
Each 1 ha plot is a small homogenous area representative of a particular landscape. As many sites as possible are selected within the super site to ensure sampling of the major of landscapes present (determined by landform, vegetation, land surface, soil and other land features). Capturing the variability at the site should also be a priority and the overall sampling strategy should include a range of soil colours and textures and vegetation compositions. Site selection can be informed by viewing satellite imagery or aerial photography.
The following points need to considered when locating sites:
Each plot should consist of three transects laid out in a star shape, with 100 observations along each (300 observations in total). The first transect runs from north to south, the second from 60º to 240º and the third from 120º to 300º.
Figure 1. Star transect layout.
The following data must be recorded for each plot, for data management purposes.
1. Lay out transect
2. Take Transect Measurements
Transect measurements are taken using a specialised measuring device consisting of: a densitometer for measuring woody vegetation; a laser pointer for measuring the ground cover and low woody vegetation; and a telescopic pole to which the laser pointer and densitometer are attached (Figure 2). The densitometer is attached to the top of the telescopic pole, while the laser pointer is attached to the same pole near the bottom, pointing downward.
Figure 2. Specialised FPC/ground cover transect measuring device.
Transect measurements are recorded in three vegetation categories: non-woody and ground cover; woody <2 m; and woody >2 m. An observation, using the measuring device, is made every metre starting at the 1 metre point of each transect. Observations are completed north to south on the first transect, 60 to 240 degrees on the second transect and 120 to 300 degrees on the third transect. A measurement is always recorded for the ground cover category. Measurements for the other two categories are only recorded if they .
Figure 3. The vegetation categories measured.
Measuring ground cover
This category includes non-woody vegetation (such as grasses, forbs and herbs), litter, cryptogams, soil and rock. There is no height restriction for the non-woody vegetation.
Ø Crust—the hard surface layer of soil.
Ø Disturbed soil—cracks in a soil crust, ant nests or other disturbances in the natural surface e.g. by animal hoof prints. In ploughed agricultural sites most soil recordings will be disturbed.
Ø Rock/lag—rock includes all stones and rock material greater than 2 cm. Lag includes all single grains that can be differentiated by the naked eye, approximately 2 mm to 2 cm.
Ø Cryptogam—a biological crust composed of lichen, moss and algae.
Ø Green leaf—a leaf with green pigmentation (one that is actively photosynthesising) attached to the plant. Sometimes the leaf in this state may appear more yellow than green. In this case a judgement call must be made as to whether it is placed in the green or dry category.
Ø Dry leaf—a leaf with non-green pigmentation (one that is not actively photosynthesising). This can include senescent (alive) vegetation as well as dead vegetation. It must be attached to the ground or plant.
Ø Litter—dead plant material that is not attached to the ground. Includes branches, leaves or fallen tree trunks.
Measuring woody vegetation less than 2 metres in height
All vegetation with a woody component and a height of less than 2 metres. These are generally shrubs and small trees.
Ø Green leaf—a green leaf attached to a plant.
Ø Dry leaf—a dead or dry leaf attached to a plant.
Ø Branch—woody component of the plant (branch or trunk).
Measuring woody vegetation taller than 2 metres
All woody vegetation with a height of 2 metres or more—trees and tall shrubs.
Ø when in canopy gap (no intercept), record as "In Crown" only
Ø when there is an interception with a canopy element record as "In Crown" AND one of "green leaf" OR "dry leaf" OR "branch
Ø record as "dry leaf" OR "branch" only (i.e. no recording is made for "in crown")
Figure 4. Illustration of various crown measurement catagories.
Site Description
To adequately describe the site a description of topography, vegetation structure, erosion characteristics, deposited materials, soil and rock colour, and tree basal area is recorded. Most of the data required is assumed knowledge or sufficiently described within the field data forms and data entry templates. Further information for some of data elements is described below.
Hillslope
To measure hillslope an observer faces in the direction of the slope, and levels the sight of the clinometer at a point in the distance which is approximately the same height as their own height The slope is recorded in per cent (0 – 100%).
Soil and Rock Colour
The Munsell Soil Colour Charts are used to record soil, rock and lag colour. Three readings are taken: hue, value and chroma. To obtain the reading a small amount of soil is held under the colour chart, to find the closest match. Both wet and dry recordings for soil crust (hard compacted surface soil) and disturbed soil (loose soil) are taken. A bottle is used to carry water to the site, to dampen the soil for the wet recordings.
Basal Area
To calculate the site tree basal area, 7 readings (one at plot centre, 6 at the halfway point of each arm of star transect). using the optical wedge prisms are taken and averaged. To use the optical wedge prism it is held at arms’ length and the observer looks through the prism at the tree being counted. If the tree trunk appears to overlap the tree viewed without the wedge prism the tree is counted (Figure 5a). If the trunk does not overlap the tree is not counted (Figure 5b). In cases where the trunk just touches, the tree is given a 1/2 count (Figure 5c). With the prism kept at a fixed point, the observer rotates 360 degrees around the prism and counts all trees that are ‘in’. The basal area is the number of ‘in trees’ multiplied by the basal area factor of the wedge prism or gauge. In Australia only optical wedge prisms with a basal area factor of 1.0 or greater are available from suppliers. Count all trees when using the wedge prism at sites with average tree diameter less than 0.3 metres
Figure 5. Using an optical wedge prism to count tree basal area.
a) an ‘in tree’—with overlap; b) an ‘out tree’—space between tree and offset image of trunk; c) a borderline tree—slight overlap between tree and offset image of trunk (Source: en.wikipedia.org/wiki/Wedge_prism)
Photos
7 photos are taken of the transect, these are: one facing the ground directly at the plot centre, one along each transect taken from the centre of the plot. Try to avoid obstructions within the photo or too much sky. Any number of additional photos may also be taken. If taking hemispheric photos at the site the following morning, leave transect tapes laid out.
Data in the field will either be directly entered into specially prepared ODK forms, or into field sheets and then transcribed later.
Data is stored in the AusCover PostGIS database, located on the AusCover UQ server. Data is downloadable from the AusCover spatial portal