Table 2.
Biodiversity attributes of lowland tropical forest (<500 m a.s.l.) on peat and mineral soil substrates in Sumatra and Kalimantan, Indonesia
| Lowland forest on contrasting substrates | ||
|---|---|---|
| Taxon and Attribute | Mineral soils a | Peat |
| (a) Woody plants | ||
| Species richness (number species per 100 stems) b | 35.2 ± 5.6 *** | 15.1 ± 4.0 |
| Fisher's alpha | 80.9 ± 10.7 *** | 18.2 ± 6.2 |
| Critically Endangered species recorded present in forest on each substrate c | 114 recorded/84 specialists | 21 recorded/3 specialists |
| (b) Bats | ||
| Species richness (rarefied number species at standard sample) d | 16.6 ± 1.3 * | 11.6 ± 0.8 |
| Bat density (total abundance per trap night) | 5.5 ± 2.7 * | 2.0 ± 0.5 |
| (c) Densities of vertebrate species e | ||
| Water monitor Varanus salvator | 0.22 ± 0.15 * | 0.00 ± 0.00 |
| Sun Bear Helarctos malayanus | 0.06 ± 0.07 | 0.00 ± 0.00 |
| Slow loris Nycticebus coucang | 0.03 ± 0.06 | 0.00 ± 0.00 |
| Helmeted hornbill Rhinoplax vigil | 0.03 ± 0.06 | 0.00 ± 0.00 |
| Small toothed palm civet Arctogalidia trivirgata | 0.03 ± 0.06 | 0.00 ± 0.00 |
| Pangolin Viverra tangalunga | 0.03 ± 0.06 | 0.00 ± 0.00 |
| Long tail macaque Macaca fascicularis | 1.07 ± 0.41 *** | 0.11 ± 0.16 |
| Barking deer Muntiacus muntjak | 0.62 ± 0.26 * | 0.11 ± 0.16 |
| Bushy crested hornbill Anorrhinus galeritus | 0.47 ± 0.21 * | 0.11 ± 0.16 |
| Red leaf monkey Presbytis rubicunda | 2.32 ± 0.54 *** | 0.62 ± 0.47 |
| Rhinoceros hornbill Buceros rhinoceros | 0.45 ± 0.25 | 0.17 ± 0.19 |
| Tufted ground squirrel Rheithrosciurus macrotis | 0.20 ± 0.17 | 0.11 ± 0.16 |
| Monitor lizard Varanus sp. | 0.15 ± 0.13 | 0.11 ± 0.16 |
| Bornean white bearded gibbon Hylobates albibarbis | 3.68 ± 0.77 | 2.87 ± 0.87 |
| Pale giant squirrel Ratufa affinis | 0.65 ± 0.29 | 0.56 ± 0.34 |
| Oriental pied hornbill Anthracoceros albirostris | 0.59 ± 0.30 | 0.68 ± 0.40 |
| Bornean bearded pig Sus barbatus | 2.27 ± 0.58 | 2.65 ± 0.78 |
| Bornean orangutan Pongo pygmaeus | 0.98 ± 0.41 | 1.32 ± 0.65 |
| Mouse deer Tragulus spp. | 0.28 ± 0.17 | 0.39 ± 0.29 |
| Pig tail macaque Macaca nemestrina | 0.11 ± 0.11 | 0.17 ± 0.19 |
| Prevost squirrel Callosciurus prevostii | 0.17 ± 0.13 | 0.39 ± 0.29 |
| Binturong Arctictis binturong | 0.06 ± 0.08 | 0.17 ± 0.19 |
| Wreathed hornbill Aceros undulatus | 0.00 ± 0.00 | 0.06 ± 0.11 |
| (d) Densities of large vertebrate Orders | ||
| Artiodactyla (deer and pigs) | 3.17 ± 0.71 | 3.15 ± 0.85 |
| Primata (primates) | 8.20 ± 1.40 * | 5.09 ± 1.24 |
| Bucerotidae (hornbills) | 1.61 ± 0.51 | 1.01 ± 0.49 |
| Carnivora (carnivores) | 0.17 ± 0.14 | 0.16 ± 0.20 |
Comparisons are made between (a) woody plants, (b) bats, and (c & d) large vertebrates. Plant data compiled from published and unpublished literature, and mammal data are derived from field surveys. All data are mean ± 95% CI.
• P < 0.05, ** P < 0.01, *** P < 0.001
a Forest on lowland mineral (non-swamp) soils excluding forest on limestone, ultrabasic rock and coarse textured sandy soil types on which kerangas vegetation develops.
b Compilation of published and unpublished records of 'local scale' (defined as <3 ha total sample plot area) woody plant surveys for stems ≥10 cm diameter at breast height (see Additional File 1: Datafile_1.xls for original data; references [87-101]). The index 'Species per 100 stems' was computed as species per stem (total species number divided by total stem number) scaled to 100 stems. Total stem number per sample was similar between peat and mineral soils samples, 430 ± 328 vs 505 ± 265, respectively. Data compiled from n = 22 for peat and n = 24 for mineral areas. Richness and Fisher's alpha compared using two-tailed t-test adjusted for unequal variance.
c Based on compilation of data on geographic range and habitat distributions from published and unpublished records for all IUCN-listed Critically Endangered (CR) plant species in Indonesia. Species shown as present in peat swamp forest are defined as all taxa with at least one record in forest reported as peat swamp forest. Species listed as present in forest on lowland mineral soils (non-swamp) are defined as all other CR species with records < 500 m a.s.l. minus those taxa that are considered specialists on azonal extreme geological features, including limestone, ultrabasic rock, or kerangas forest types that form on podzolized soils on coarse textured sedimentary rocks. Species treated as specialists on peat or mineral soils are defined as taxa with records from only one ecosystem type. A full accounting of CR species recorded as present in peat is provided in Additional File 2: Datafile_2.xls.
d Based on harp-trap inventories of insectivorous bats captured at three locations each in forests on peat in Kalimantan (Danau Sentarum, Sungai Putri, Tanjung Puting), and forests on mineral soils in Kalimantan (Barito Ulu, Sungai Lesan) and Sabah (Danum Valley). Individual captures at each site were rarefied 1000 times in EstimateS to compare species richness at a standard number of individuals (n = 128, the capture number in the smallest inventory at Danau Sentarum). Capture rate - total bat abundance per trapping effort at a site - is a surrogate estimate of density.
e Vertebrate densities were measured along permanent census routes in lowland forest on peat and mineral soil substrates at Gunung Palung National Park, West Kalimantan, Indonesia. Table shows total number of independent observations (Mean no. km-2) of large bodied vertebrates between August 2000-2002 in lowland mineral areas (N = 170 surveys, 591.7 km) and peat forest (N = 87 surveys, 290.6 km). Species are sorted by increasing relative density on peat versus mineral soils. Note that, as this is a sample from a single site, specific values as well as presence/absence may vary substantially across sites.