Seedling composition, growth, and dynamics in tropical rain forest, La Selva, Costa Rica (1983-1996)

Recruitment, growth, and survivorship of the regeneration stages of trees and lianas were studied in old-growth tropical rain forest at La Selva Biological Station of the Organization for Tropical Studies (OTS), near Puerto Viejo de Sarapiquí, Heredia Province, in the Caribbean lowlands of Costa Rica. A total of 48 permanent seedling transects each measuring 10 m x 0.5 m were established at random locations within three La Selva permanent forest inventory plots. The forest plots occupy contrasting landforms: Plot 1 (4.4 ha), old alluvial terrace; Plot 2 (4.0 ha), swamp forest and low hills; and Plot 3 (4.0 ha), steeply dissected terrain with residual volcanic soils. Seedling locations are georeferenced within the grid system of the permanent forest inventory plots, facilitating spatial analysis of seedling populations with respect to adult cohorts. Beginning in June 1983, all seedlings ≤ 0.5 m in height belonging to tree and liana species capable of reaching 10 cm diameter at breast height (dbh) at maturity were tagged, identified to species or morphospecies, mapped to the nearest cm, and measured in height to the nearest cm. Over a period of 18 months, a total of 6403 seedlings belonging to 167 species were tagged. Monitoring and re-measurement of all tagged individuals continued through November 1996. Data include 17 census dates over a period of 13.5 years. At the time of the final census, only 97 individuals (1.52% of the tagged seedlings) were still alive, representing 43 species (25.7% of the initial number). The largest surviving seedling had grown in height from 4 cm to 13 meters during the study period. This dataset on the regeneration stages in old-growth tropical rain forest in the La Selva permanent inventory plots forms a complement to the studies of long-term growth and demography of these species and assemblages at adult stages within the plots. Forest inventory data for trees and lianas ≥ 10 cm dbh in the permanent plots in which the seedling transects were established were previously archived and can be accessed at: Hartshorn, G.S., D.D. Lieberman, M.E. Lieberman, R. Peralta Lobo, and C.E. Johnson. 2022. “Long-term dynamics of tropical rain forests in permanent inventory plots, La Selva, Costa Rica (1969-1995)” ver 3. Environmental Data Initiative. https://doi.org/10.6073/pasta/240bf29397facc19984740ee113ab2ed. Description of archived material The archived materials include these components: (1) The master data file comprises data on 6403 tagged seedlings in 48 transects within the three permanent inventory plots at 17 census dates from June 1983 to November 1996. Each line in the data represents an individual tagged seedling. The array has 6403 lines x 27 columns of data, divided into three portions corresponding to the three plots: Plot 1 has 1861 lines, Plot 2 has 2835 lines, and Plot 3 has 1707 lines. Data are ordered first by transect and next by meter (1-10). Information for each seedling includes tag number, numerical species code, family, genus and species, north-south coordinate (cm) from the NW corner of the plot, west-east coordinate (cm) from the NW corner of the plot, and seedling height (cm) at each census date. A height value of zero is given if the highest active meristem remains at ground level, as is often seen in young palm seedlings. A negative value indicates that the stem apex is lower than the rooting site, which could occur if the seedling is rooted above ground level, for example on a nurse log. A code of 999 is used to fill the matrix for census dates prior to the appearance of a seedling and census dates after its death; a code of -999 indicates the census at which a seedling was first recorded as dead. A detailed list of column identifiers appears in the Other entities section. (2) A taxonomic reference list includes all tree and liana species occurring in the three permanent plots during the 1969-1995 forest inventories. The numerical species code is given together with the family, genus, species (or morphospecies), and taxonomic authority. For most species, habit is indicated (liana, treelet, understory tree, subcanopy tree, canopy tree, or emergent tree). The list is presented in two forms, one ordered numerically by the species code and the other alphabetically by family, genus, and species.