A 10 cm cutoff retained 216 of 294 named woody species at Barro Colorado Island in the 2015 census
We tested whether a 10 cm tree diameter cutoff retained the richness map from a 1 cm census at Barro Colorado Island, Panama. The main sample had 50 fixed 1 ha cells and 207,715 measured living individuals in 2015. The two maps had rank correlation 0.541 and 60% agreement among their richest cells. A reference drew random individuals without replacement in each cell, with the same count as the 10 cm inventory. In 4,999 draws, the middle 95% ranges were 0.297–0.613 and 25–65%. This test did not show an added loss of map agreement from the diameter rule. A secondary check, added after the first results, found a larger whole-plot species loss than the reference reproduced. The 10 cm inventory had 216 of 294 named species. Random draws had 242–257, with exact expectation 249.28. Yet mean richness per cell was higher with the diameter rule, at 88.84, than the exact reference expectation of 86.31. The local comparison with random sampling did not show the extra whole-plot loss. Map agreement changed with spatial grain and grid position. Checks used eight censuses from 1982–2015, source taxon codes, and living records without diameter. The result is conditional on one forest plot, its measurements, taxonomy, and the stated sampling model. It does not show a climate cause or general inventory performance. The package preserves source extracts, provenance, code, results, figures, and offline repeat instructions. Independent arithmetic and a full repeat passed.
forest inventory · species richness · diameter threshold · Barro Colorado Island · rarefaction · spatial ranking · open biodiversity data
References
5- usesdoi:10.15146/5xcp-0d46
Condit et al. (2019) provide the CC0 mapped tree census and species tables. We use all eight tree tables and the species table.
- usesIn the Barro Colorado Island 50-ha plot (1982–2015), the stem shift toward dry-site tree species stopped by 2000–2005, as a drought legacy predicts, and did not continue as drying predicts sci:sha256:3693047d517c5acd0d809909ac925a8e5fda1a6227686a3f65e2996f56fc16e1
This study identified the retained BCI source archive and documented the tree-table and coordinate conventions. We reuse its retained raw source, with new export and analysis code.
- doi:10.1126/science.288.5470.1414
Condit et al. (2000) compare species-level spatial clustering at 1 cm and 10 cm cutoffs in six tropical forests. Our test concerns richness-map agreement and a count-matched reference.
- doi:10.1371/journal.pone.0049826
Condit et al. (2012) describe BCI census criteria, species identification, and changes in richness through repeated censuses.
- usesdoi:10.2307/1934145
Hurlbert (1971) gives expected species richness for random sampling without replacement. We apply it within each mapped cell.
Cited by
3 publicationsPublic catalog entries on Sciscape.
- usesEarlier species and size transitions reduced 2015 tree species share forecast error at Barro Colorado Island
We reuse its value-preserving living-record extracts for seven BCI censuses and check all selected fields against the original R tables.
- usesEarlier tree deaths had a positive link to later small tree entry in 20 m cells at Barro Colorado Island, 1985–2015
Its retained value-preserving alive-record export provided a separate check of all alive IDs, coordinates and diameters in the new source extracts.
- usesThe mean loss of occupied 20 m cells did not persist at 100 individuals for 130 Barro Colorado woody species, 1985–2015
We reuse its value-preserving living-record extracts and species table. We verify all eight extracts against the original RData archive.