Standard Procedures and Protocols for Cooperative Investigators at the Free-Air CO2 Enrichment Site (FACTS-1) in the Duke Forest
- The FACE experiment in the Duke forest consists of 6 "rings", each approximately 30-m in diameter, located in the Blackwood Division of the Duke forest as shown on the attached map. All activities in these rings and in the adjacent forest area shown on the map must be approved by the principal investigators (Ram Oren and George Hendrey) and the Office of the Duke Forest (Judd Edeburn) before commencement. As manager of the Duke Forest, Judd Edeburn must approve of all activities in surrounding areas of the Duke Forest (not shown on the site map).
- The FACE rings are numbered as shown on the map, and all studies are expected to use these designations in their field research, collections, and management of data.
- Rings 2, 3 and 4 are supplemented with carbon dioxide in an attempt to maintain a constant 200 ppm differential (nominal elevated target of 550 ppm) between the rings. This treatment began on 27 August 1996. Rings 1, 5 and 6 remain at ambient CO2 but they receive a volume of air equivalent to that injected into the enriched plots. For statistical purposes, it is anticipated that pairs of rings are best considered as blocks; viz. 1 & 2; 3 & 6; and 4 & 5.
- Unless specific permission is obtained to the contrary, all studies will be allocated to one of 3 "sectors" within each ring, as shown on the attached diagram. These sectors are as follows: a. "Physiology:" The physiology sector consists of the ground area occupied by the wooden boardwalks that form a cross in each ring, the area occupied by the central walk-up tower, and the area that is within a 1-m "reach" of these structures. This sector comprises the vertical space above this ground area. All investigations that require canopy access will be assigned to the physiology sector. Canopy access will be available to FACE researchers via the central tower and via "personnel-lifts" that will travel along the boardwalks. All studies requiring frequent access to sample vegetation are expected to be conducted in this sector, using the board walks to minimize damage to the soil surface and understory vegetation. Minor amounts of vegetation (e.g., plant tissues for N analysis) may be removed from within the volume of this sector. b. "Vegetation:" The vegetation sector in each ring consists of 4 pie-shaped units, as shown on the attached diagram. All studies focusing on the long-term growth, population density, diversity, and function of above-ground portions of the vegetation will be conducted in these sectors. It is expected that repetitive access (e.g., to make a data collection) to this sector should not be more frequent than monthly intervals. It is also expected that no living vegetation will be removed from this sector, and no soil disturbances are allowed. The vegetation sectors are recognized by a 3-component numbering scheme, shown on the field signs. The first number is the ring number the second number (either V or S) designates the sector, and the third number (1-4) designates the subplot?beginning consecutively with plot #1 in the northeast quadrant and progressing clockwise (e.g., 3v2 is subplot 2 (southeast) of the vegetation sector in ring 3). c. "Soil:" Like the vegetation sector, the soil sector in each ring consists of 4 pie-shaped units, which are numbered consecutively in a clockwise direction beginning in the northeast quadrant. All studies that require disturbance and access to the belowground portion of the forest ecosystem will be conducted in these areas, including emplacement of soil lysimeters and gas wells, and removal of cores for soil analysis and root extraction. All soil cores should be backfilled with similar soil materials gathered well outside the FACE rings. Repetitive access to the area within the soil sector should not be more frequent than biweekly intervals.
- No trees, large branches, or shrubs shall be removed from inside or immediately adjacent to a ring. (We define a large branch as any branch section with more than one season's growth.)
- As shown on the site map, each ring is accessible from its northern side by a graveled road; however, this road is not to be used for regular vehicle access. Researchers should park in designated parking areas along the main roads and walk to individual rings along the short gravel roads or along the pathway parallel to the utility corridor that connects all rings. Permission to use the short graveled roads to deliver heavy equipment to a ring must be obtained from the field site manager.
- Researchers are expected to maximize their use of the boardwalks to access the sectors within each ring. Foot traffic around the periphery of the ring is tolerated, but discouraged. No one is allowed to climb or to attach large objects to trees and shrubs within or adjacent to the rings.
- No equipment or enclosures shall be permanently mounted within or immediately adjacent to the rings, including the central and peripheral towers and the wooden boardwalks, without permission of the site manager.
- It is recommended, but not required, that researchers assume a buffer zone of about 2-m width, where CO2 control will be suboptimal, near the outside of the plot.
- All research requiring canopy access should be conducted in accord with standard safety procedures used by Duke Forest personnel, following protocols maintained in the Office of the Duke Forest. Researchers should be aware of the following FACE-specific safety items: a. No Investigator may use the access towers or personnel lifts without undergoing annual safety and operations training. b. At least one other scientist must be "on site" whenever an investigator uses either of these facilities for canopy access. c. Workers on the ground must wear hard hats whenever other workers are in the canopy. d. All workers should return to ground level and leave the site whenever thunderstorms are in the vicinity of the Blackwood Division. e. No personnel should climb peripheral ring towers without approval of the site manager. The safety rules (above # b-e) will apply to when workers are climbing the peripheral towers. f. Personnel lifts should be parked at the ends of the board walks when not in use.
- No investigator should alter, interfere, or manipulate the equipment used to supply and regulate the concentration of carbon dioxide in FACE rings. The operation of the FACE plots is strictly within the purview of personnel from Brookhaven National Laboratory.
- The use of field markers within the FACE rings must be approved by the principal investigators and the site manager. To minimize confusion, we will reserve the use of specific colors of "flagging" for specific studies. As of this date, the following colors are in use: Blue: Designates sector boundaries and other administrative aspects (Schlesinger, Hendrey et al.). Orange: Studies of tree growth (DeLucia and Thomas) Dark Red: Soil Lysimeters (Richter and Schlesinger) Pink Red: Studies of canopy phenology and needle demography (Ellsworth) Line "Glow": Studies of canopy insects (Lincoln) Yellow: Biodiversity (Clark/Mohan)
- Before beginning the work anywhere within the FACTS-1 project site, all investigators must check in at the field office and coordinate their field activities with Robert LaMorte (919-932-1415), who is the field site manager. Activities in the area surrounding the FACTS-1 facility must be coordinated through the Office of the Duke Forest by contact with Judd Edeburn (919-660-8013).
- This protocol is subject to change at any time, and any investigators affected by changes in policy will be notified immediately. Investigators operating in violation of these procedures, or allowing their associates to do so, will be asked to terminate their activities at the site.