Table 3 Summary of methods used in the studies included in the review
From: Systematic review of effects on biodiversity from oil palm production
Study | Taxonomic group | Collected data | Sampling method | Methodology |
|---|---|---|---|---|
Invertebrates | Â | Â | Â | Â |
Brühl & Eltz [36] | Ground-dwelling ants | Species richness | Tuna baits | Baits along 105 transects of various lengths (10-100 m) |
Chey [31] | Moths | Species richness, abundance and composition | Light traps | One light-trap at each site for 3 consecutive nights. |
Chang et al. [27] | Mosquitoes | Species richness and abundance | Human baits | All-night human landing collections on 5 consecutive nights each year. |
Chung et al. [21] | Subterranean beetles | Species richness, abundance and composition | Winkler sampling | Ten 1Â m2 samples of leaf litter and soil at each site. |
| Â | Understorey beetles | Species richness, abundance and composition | Flight-interception-trapping | 3 traps per site. Two weeks of sampling. Only samples from alternate days used. |
| Â | Arboreal beetles | Species richness, abundance and composition | Mist-blowing | 10 trees at least 10Â m apart |
Davis & Philips [22] | Dung beetles | Species richness and abundance | Pitfall traps | 4 sites per habitat, 3 traps per site at least 10Â m apart, two 24-hour periods |
Fayle et al. [42] | Canopy ants | Species richness, abundance and composition | Fogging | 20 transects per habitat |
| Â | Ants in the ferns | Species richness, abundance and composition | Entire ferns collected, litter and core fragments processed. | 20 transects per habitat |
| Â | Leaf litter ants | Species richness, abundance and composition | Litter samples | 20 transects per habitat |
Hashim et al. [41] | Ants | Species richness | Hand-collecting and pitfall traps | 3 randomly-distributed 0.25 m2 subplots within each of three 10 m × 10 m plots and 5 pitfall traps per habitat. |
Hassall et al. [35] | Terrestrial isopods | Species richness and abundance | Quadrats | Plots sampled on a stratified random basis. |
Koh & Wilcove [28] | Butterflies | Species richness | Banana-baited traps | 98 trapping sites with total of 48 hours of trapping |
Liow et al. [43] | Bees | Species richness, abundance and composition | Honey-baited traps in transects | Non-randomly selected 1-3 transects per site. On average 12.85Â hours surveyed per transect |
Lucey & Hill [32] | Ground-dwelling ants | Species richness, abundance, and composition | Pitfall traps | 2000Â m transects, f1ve traps per trap station, six trap stations in forest and in oil palm plantations, 100Â m between trap stations. Sampled twice for 12 consecutive days. |
| Â | Butterflies | Species richness, abundance, and composition | Fruit-bated traps | Two 2000Â m transects, 10 trap stations in forest and in oil palm plantation, 100Â m between trap stations. Sampled twice for 12 consecutive days at both occasions. |
Room [44] | Ground foraging ants | Species richness, abundance and composition | Quadrats | 30 samples per habitat. |
Vaessen et al. [33] | Termites | Species richness, abundance and composition | Transects | One transect established randomly at each site. |
Vertebrates | Â | Â | Â | Â |
Aratrakorn et al. [45] | Birds | Species richness and relative abundance | Timed Species Counts | 30 oil palm plantations selected from aerial photographs. The number of sites based on preliminary counts. Two counts of 20Â min divided into five 4-minute blocks. |
Azhar et al. [26] | Birds | Species richness, abundance and composition | Transect counts | 470 various-length transects: 418 in plantation estates, 52 in smallholdings and 20 in peat swamp forest. |
Bernard et al. [34] | Non-volant small mammals | Species richness, abundance and composition | Live cage traps with baits | 50 traps per trapping site arranged into 5 200Â m long trap lines. |
Danielsen & Heegaard [46] | Birds, primates, tree-shrews, and squirrels | Species richness, abundance, and composition | Variable-distance line-transect | 2000Â m straight line; surveyed for 40 hours in forest areas and for 20 hours in oil palm. |
| Â | Bats | Species richness, abundance, and composition | Mist nets | 15-20 nets (totaling 150-250Â m). |
Edwards et al. [47] | Birds | Species richness and abundance | Timed point-counts along transects | 5 sites per habitat, 12 sampling points at 250Â m intervals at each site. |
Fukuda et al. [48] | Bats | Species richness and abundance | Mist nets and harp traps | 2-4 mist nets per night, 3-6 census points per habitat. |
Gillespie et al. [39] | Amphibians | Species richness and composition | Transects | 400Â m transects; 6 in wet forest, 5 in dry forest, and 3 in oil palm plantation. Each sampled 3-4 times. |
Glor et al. [49] | Lizards | Species richness and abundance | Glue traps | Non-randomly selected 10 x 10 m trapping grids with 20 traps each, 3 plots in oil palm, 4 in mogote. |
Juliani [40] | Bats | Species richness and abundance | Mist nets | 10 mist nets randomly placed in each habitat type. |
Birds | Species richness and abundance | Point counts | 240 point counts arbitrary chosen. At least 200Â m from each other. 127 sites in the oil palm. | |
Sheldon et al. [37] | Birds | Species richness, abundance and composition | Point counts | 20 three-minute point counts at 50Â m intervals along the transects. |