Jul 14, 2024
Standardized Protocol for Transect Set-up and Palm Inventory for the DOPAMICS Research Program
- Julien Engel1,
- Kevin Mabobet1,
- Jean-Louis Smock1,
- Marc Testé1,
- Louise Brousseau1
- 1Institut de Recherche pour le Développement, UMR AMAP
External link: https://dopamics.wordpress.com/
Protocol Citation: Julien Engel, Kevin Mabobet, Jean-Louis Smock, Marc Testé, Louise Brousseau 2024. Standardized Protocol for Transect Set-up and Palm Inventory for the DOPAMICS Research Program. protocols.io https://dx.doi.org/10.17504/protocols.io.14egn73kqv5d/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: March 09, 2022
Last Modified: July 14, 2024
Protocol Integer ID: 59251
Keywords: DOPAMICS, pre-Columbian societies, ring ditch, life science, human science, landscape history, Arecaceae, forest inventory, botany, Neotropical palms, Oenocarpus, Astrocaryum, Euterpe, transect, French Guiana, Guyane française, ERC, domestication, adaptation, palm uses, biodiversity, useful diversity, phenotyping, phenotypic diversity, incipient domestication, semi-domestication, wild population, Amazonia, rainforest, European Research Council, Starting Grant, adaptation, microevolution, Holocene, phenotyping, phenotyping, intra-specific diversity, inter-specific diversity
Funders Acknowledgement:
ERC
Grant ID: DOPAMICS grant number 101039272
Disclaimer
DOPAMICS is funded by the European Union under grant no. 101039272. Views and opinions expressed are those of the authors only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency (ERCEA). Neither the European Union nor the granting authority can be held responsible for them.
Abstract
We describe the protocol developed as part of the ERC-funded DOPAMICS research program for setting up transects and conducting palm inventories in three forested pre-Columbian sites in French Guiana: MC87 near Régina, the "Grand plateau" in the CNRS Nouragues Research Station, and Mont Galbao near Saül.
The objective of this field survey was to assess the distribution of Neotropical palms and to conduct following geoarchaeological surveys, and soil and palm sampling. In each study site, a transect approximately 1,000 metres long was set up from a pre-Columbian ring ditch and extended through the surrounding landscape. The transects were positioned to span different levels of human occupation (from pre-Columbian ring ditch hills with strong evidence of human occupation, RH, to adjacent hills or slopes with no or sparse evidence of pre-Columbian occupation, AH) and different microhabitats (including well-drained terra-firme and waterlogged bottomlands). Palms were inventoried over a band of 20 metres in width around the central line.
This protocol is made open access under the Creative Commons Attribution License (CC-BY). It details the inventory strategy and steps, and the material needed with the aim to encourage future reuses of this protocol for the same or similar research purposes, and to improve the reproducibility of the research conducted. Reuse of this protocol must credit the authors and mention its DOI.
Image Attribution
Louise Brousseau #DOPAMICS2023
Materials
- Satellite phone
Iridium 9505A
- GPS
Garmin GPSMAP 66s
- Topographic map of the study area
- Precision compass
Suunto KB-14
- 21 pickets of 60-80 cm (for a transect of 1,000 meter long)
- Measuring tape of 60 or 100 meter long
Stanley Fibreglass Long Tape Measure 60m
- 3 graduated ropes of 100 meter long (graduated every 10 meters with adhesive tape)
- PVC tree labels
- Hip chain (topofil) or a spool of polypropylene thread (1000-2000 meters) to measure and mark the central line of the transect.
- Coil of wire to fix labels on palms
- Laser telemeter
Laser Technology TruPulse 360°R
- Measuring tape of 2 m long
- Diameter tape (D-tape) or Tree caliper
- Lithium batteries for the GPS and laser telemeter
- Permanent markers
Pentel Pen Permanent Marker 4.3mm bullet point tip N50
- Waterproof notebook and pencils
"Rite in the rain" all-whether fieldbook or notebook
Safety warnings
Working in isolated areas of the Amazonian rainforest can be dangerous. To ensure safety, it is important to carry a fully charged satellite phone and GPS device, and a first aid kit. It is also advisable to consult a doctor to undergo a health check-up before embarking on remote expeditions.
Before start
- Make sure the satellite phone and GPS batteries are fully charged.
- Make sure that the laser telemeter is calibrated.
- Gather all necessary materials, prepare the pickets and graduated ropes.
- Weigh the materials before transporting them by helicopter.
Foreword: Overview of the transect design and target palm species
Foreword: Overview of the transect design and target palm species
Figure 1. LiDAR-derived Digital Elevation Model (background) and representation of the transect installed at MC87 near Regina, French Guiana (black line). The ring dicth is visible in the western part of the transect.
A ring ditch is a geometric earthwork of pre-Columbian origin that can be found in various forested areas of the Amazonian rainforest. It is typically an archaeological artifact whose function is still not fully understood. Ring ditches can vary in size, ranging from a few dozen meters to several hundred meters in diameter. They are particularly abundant in inter-fluvial areas of French Guiana (northeast Amazonia) but also in other regions of Amazonia, such as in northern Brazil or Bolivia.
Starting from the ring ditch with strong evidence of human occupation, the transect extends through the surrounding landscape, spanning different microhabitats including well-drained terra-firme of hilltops and slopes and waterlogged bottomlands.
Note
DOPAMICS research program focuses on five target palm species that have high social and ecological values:
- Understorey palms : Astrocaryum paramaca, Astrocaryum sciophilum
- Tall palms : Euterpe oleracea, Oenocarpus bacaba, Oenocarpus bataua
These palm species belong to the Arecoideae sub-family and are native from the Neotropics. They are locally abundant in the Amazonian rainforest. In particular, Oenocarpus bataua and Euterpe oleracea are hyperdominant, ranking at the 7th and 8th position of the most abundant species in forest inventories (ter Steege et al. 2013. "Hyperdominance in the Amazonian Tree Flora". Science). Oenocarpus bacaba, Oenocarpus bataua and Euterpe oleracea are pan-Amazonian. The distribution of Astrocaryum paramaca and Astrocaryum sciophilum is restricted to northeast Amazonia, and they are very abundant in the Guiana shield: Guyana, Suriname, French Guiana (GBIF.org (year), GBIF Home Page. Available from: https://www.gbif.org). Neotropical palms have a central role for human societies in the Amazon since pre-Columbian times, serving multiple purposes as sources of food -such as purees and oils- and materials -such as basketry and building materials (Wallace, A. R. 1853. "Palm Trees of the Amazon and Their Uses"). Recent studies have shown that thes species are more abundant at pre-Columbian sites than in wild, undisturbed forest areas. As such, they are credited as "biological indicators" ancient human occupation (Odonne et al. 2019. "Long-term influence of early human occupations on current forests of the Guiana Shield". Ecology).
Exploration of the study area
Exploration of the study area
2d
Survey the forest area surrounding the ring ditch hill:
- Assess whether the target palm species are present on the ring ditch hill (RH) and in the surrounding landscape.
- Inspect uprooting mounds at the foot of fallen trees to detect the presence of archaeological artefacts such as ceramic fragments and charcoals.
This preliminary evaluation helps determine the distribution of the target palm species and of pre-Columbian occupation in the study area to position the transect. Then,
- Select an adjacent hill or slope (AH) at a maximum distance of 1km from the ring ditch with: (1) target palm species and (2) no or sparse evidence of pre-Columbian occupation such as earthworks, abundant ceramic fragments or other archaeological artifacts.
Note
At the study site of Mont Galbao, the transect ends in the bottomland due to the absence of palms on adjacent hills and slopes.
Setting-up of the transect central line
Setting-up of the transect central line
1d
Starting from the transect start:
- Plant a picket at the start of the transect
- Label the picket with a permanent marker (Picket ID= "Cstart")
- Record the GPS position of the picket
- Follow the direction of the transect's endpoint using a precision compass and mark the central line with a wire until you reach the end of the transect
- Plant a picket at the end of the transect
- Label the picket with a permanent marker (Picket ID= "Cend")
- Record the GPS position of the picket.
Note
When using the precision compass, make sure to adjust for the magnetic deviation between geographic north and magnetic north.
Figure 2. Photo of the central line in the study site of Mont Galbao. Photo credit: Julien Engel #DOPAMICS2022
Setting-up of a 20-metre-wide band around the central line and quadrats
Setting-up of a 20-metre-wide band around the central line and quadrats
1w
From the transect start,
- Position the first graduated rope (100-metre long, with graduations every 10 meters marked with adhesive tape) along the central line (Y-axis)
- Plant a picket at 50 and 100 metres along the central line
- Label the pickets with a permanent marker and record their GPS positions.
Note
Picket ID: [Cx]
[Cx]= "C1", "C2", "C3", etc.
With the 60-m measuring tape,
- Position the second graduated cord parallel to the central line, 10 meters apart, to delimit a band of 10-metre wide on the left side of the central line
- Position the third graduated cord parallel to the central line, 10 meters apart, to delimit a second band of 10 meters wide on the right side of the central line.
Figure 3. Scheme showing the central line and graduated cords along and parallel to the central line to delimit a 20-meter wide band around the central line and 10 x 10 m quadrats.
- Inventory palms within each 10 x 10 m quadrat (shaded area in Figure 3) → see next steps "Palm inventory" and "Palm field phenotyping"
Palm inventory
Palm inventory
2w
Within each 10 x 10 m quadrat:
- Identify target palm species
| A | B | C | D | E | |
| Astrocaryum paramaca | Astrocaryum sciophilum | Euterpe oleracea | Oenocarpus bacaba | Oenocarpus bataua | |
| Understorey palm species, stemless (acaulescent), black winged spines on the petioles and base of the rachis, leaf underside: white, free (unwelded) terminal leaflets (i.e. pinnae) | Understorey palm species, single-stemmed, up to 8m tall, round or slightly flattened spines on the petioles and base of the rachis arranged in oblique lines, leaf underside: white, welded terminal leaflets (i.e. pinnae) | Tall palm, often in clumps (cespiteux), up to 20m tall, no spines, distribution restricted to hygromorphic bottomlands | Tall palm, single-stemmed, up to 25m tall, no spines, leaf underside: green, leaflets (i.e. pinnae) distributed on different plans along the rachis | Tall palm, single-stemmed, up to 25m tall, no spines, leaf underside: white, leaflets (i.e. pinnae) distributed on the same plan along the rachis |
Table 1. Main characteristics of the targeted palm species. For more information, consult the book "Guide des palmiers de Guyane" by J.J. de Grandville & M. Gayot. Office National des forêts, 2014, 272p (ISBN 978-2-84207-374-9).
- Assign individual palms of the target palm species to a unique identifier ([palm-ID]) and label it with a plastic label.
Figure 4. Euterpe oleracea labelled at Mont Galbao. The label indicates the palm ID (here, 362) and the quadrat number (here, Q=164). Photo credit: Julien Engel #DOPAMICS2022.
Note
Non-redundant palm ID formatting: [SITE ID]-[palm ID]
- [site ID]= "MC87" (MC87), "NOUR" (Nouragues), "GALB" (Mont Galbao)
- [palm ID]= 0001, 0002, 0003, etc. (3- or 4-digit number)
Palm ID formatting (on site): [palm ID]
Note
Exclusion criterion: saplings lower than one meter tall can be excluded from palm inventory.
Note
In the specific case of Euterpe oleracea palm clumps, label one stipe only.
- Record the GPS position of the palm.
- Assign the palm to a position in the forest layers, a categorical variable that describes the vertical position of individual palms : forest floor, understorey, sub-canopy.
| A | B | C | |
| Position in forest layer | Encoding | Description | |
| Forest floor | FF | Acaulescent palm without stipe | |
| Understorey | UN | Stipe < 10 m | |
| Sub-canopy | SC | Stipe > 10 m |
Table 2. Encoding of palm position in forest layers.
⇒ In the field notebook, note: [palm ID], [quadrat number], [species], [GPS point number], [position in forest layers]
Palm field phenotyping and phenological monitoring
Palm field phenotyping and phenological monitoring
Palm field phenotyping
Because the target palm species have different intrinsic characteristics, different descriptors are used for field phenotyping.
| A | B | C | D | E | F | |
| Species | Intrinsic species characteristics | Height | DBH | Number of stipes | Length of the longest rachis | |
| Astrocaryum paramaca | Always acaulescent (stemless) | X | ||||
| Astrocaryum sciophilum, Oenocarpus bacaba, Oenocarpus bataua | X | X | ||||
| Euterpe oleracea | Often in clumps (cespiteux) | X | X | X |
Table 4. Field phenotypic traits to measure depending on intrinsic species characteristics.
For Astrocaryum sciophilum and Oenocarpus spp.:
- With the laser telemeter, measure the stipe height from the ground to the base of the crown (i.e. point of insertion of the lowest living leaf)
- With the diameter tape (D-tape) or tree caliper, measure the stipe Diameter at Breast Height (DBH).
Figure 5. Scheme showing how to measure palm height with a laser telemeter.
Note
Measuring height in 3-shots with the TruPulse 360°R (Laser Technology):
- Press the up arrow until "HT" and "HD" flash
- Aim anywhere you have a clear line of sight and press "Fire" (the distance to the stipe will appear in the Main Display)
- Aim to the base of the palm crown and press "Fire" (the first angle Θ1 will appear in the Main Display)
- Aim the base of the stipe and press "Fire" (the first angle Θ2 will appear in the Main Display)
- The heigh is automatically calculated and appear in the Main Display.
Note
- Specific case 1: Small palms (juveniles) are stemless.
→ The height and diameter are recorded as "NAP", meaning that these descriptors are "not applicable", see figure 6 below.
- Specific case 2: Palm stipes can be not accessible, because of an accumulation of spines or old leaves hiding the stem.
→ The stipe diameter is recorded as "NACC", meaning that this descriptor are "not accessible".
Figure 6. Example of an acaulescent O. bacaba at Mont Galbao. Photo credit: Julien Engel #DOPAMICS2022.
For Euterpe oleracea :
As E. oleracea often occurs in clumps,
- Count the number of stems (i.e. stipes) in the clump. If there is only one stem, count "1".
- With a laser telemeter, measure the height of the tallest stem from the ground to the base of the crown (i.e. point of insertion of the lowest living leaf).
- With the D-tape or tree caliper, measure the DBH of the largest stem.
Note
Alternatively, it is possible to measure the height and diameter of every stipes. Because it is very time-consuming, this alternative was not retain in the present protocol.
For Astrocaryum paramaca :
As A. paramaca is always acaulescent (stemless),
- With the measuring tape, measure the length of the longest rachis.
⇒ In the field notebook, note: [height], [dbh], [number of stipes], [length of the longest rachis]
Phenological monitoring
- Monitor the phenology of palms and encode it as follow:
| A | B | |
| Phenology | Encoding | |
| Sterile | S | |
| Flowering | FL | |
| Fructifying (unripe fruits) | UF | |
| Fructifying (ripe fruits) | RF |
Table 5. Encoding palm phenology.
- If the palm is fructifying, count the number of bunches, see figure 7.
Figure 7. Example of bunch of Astrocaryum sciophilum with ripe fruits. Photo credit: Cyril Gaertner #DOPAMICS2022.
Note
If the palm is both flowering and fructifying or bears bunches of different maturity, it is possible to note both : e.g. "FL+UF" ; "UF+RF"
⇒ In the field notebook, note: [phenology], [number of bunches]
| A | B | C | |
| Descriptor | Type | Encoding | |
| Site ID | Categorical | MC87, NOUR, GALB | |
| Palm ID (on site) | Integer | [3- or 4-digit number] | |
| Non-redundant palm ID | Categorical | [site ID]-[palm ID] | |
| Quadrat number | Integer | [3- digit number] | |
| Species | Categorical | [species] | |
| GPS point number | Integer | [3- or 4-digit number] | |
| Position in forest layer | Categorical | FF, UN, SC | |
| Number of stipes | Integer | [number] or NAP | |
| Height | Decimal or categorical | [number] or NAP | |
| Diameter | Decimal or categorical | [number] or NACC or NAP | |
| Length of the longest rachis | Decimal or categorical | [number] or NAP | |
| Phenology | Categorical | S, FL, UF, RF | |
| Number of bunches | Integer | [number] |
Table 6. Recap of the descriptors and their encoding.
FF = forest floor, UN = understorey, SC = sub-canopy
NACC = not accessible, NAP = not applicable
S = sterile, FL = flowering, UF = fructifying (unripe fruits), RF = fructifying (ripe fruits)
Repeat the operation every 100m along the entire transect.
go to step #4
After end
After end
2w
After returning from the field:
- Convert inventory data to electronic format using Excel or an equivalent program (file format: tab-separated .txt or .csv).
- Export GPS data so that they can be loaded into Geographic Information System (GIS) mapping software, such as QGIS, on a topographic (IGN) and/or LiDAR-derived DEM background.