Model-ready benchmarks for NPP, ANPP, litter fluxes, and recruitment into the 1 cm dbh size class

Author(s): Ward R; Hanbury-Brown A; Kueppers L

Site ID: XX-Glo

Site Name: Global

Variables: Aboveground net primary productivity (ANPP); Leaf litter flux; Net primary productivity (NPP); Reproductive litter flux

Date Range: Jan. 1, 1980 - July 3, 2018

Description: The intended use of this dataset is to serve as an observational benchmark to evaluate model predictions of NPP, ANPP, litter fluxes, and recruitment at Barro Colorado Island, Panama. This dataset contains four CSV files and one text file. “Benchmarks-NPP-ANPP-R-L.csv” provides estimates of annual ecosystem-level reproductive litter flux (R), leaf litter flux (L), aboveground net primary productivity (ANPP), and net primary productivity (NPP) for 61 field plots throughout tropical, temperate, and boreal forest biomes. An additional 499 plots (n = 550) include estimates of just R, L, and R/L. Each row reports a distinct set of estimates for one sampling interval at one plot. “Metadata-Benchmarks-NPP-ANPP-R-L.csv” contains field descriptions for all data fields in “Benchmarks-NPP-ANPP-R-L.csv”. “References-Benchmarks-NPP-ANPP-R-L.txt” contains full references to the original studies used to produce the observations at each plot included in the data. “Benchmarks-Recruitment.csv” provides estimates of species-level recruitment rates into the 1 cm dbh size class at four CTFS-ForestGeo sites using methods that account for unobserved mortality of new recruits between census intervals (Kohyama et al., 2018). “Metadata-Benchmarks-Recruitment.csv” contains field descriptions for all data fields in “Benchmarks-Recruitment.csv”.

QA/QC: Full QA-QC

Methods Description: NPP, ANPP, R, and L were synthesized from a corpus of prior literature (see References-Benchmarks-NPP-ANPP-R-L.txt) and data representing 550 sampling plots (i.e. “subsites”) globally. Subsites reporting reproductive litterfall, leaf litterfall, ANPP and NPP were found by querying Web of Science, Google Scholar, Scielo, and publicly available ecological monitoring network metadata available between 1966 and 2021 using the following query terms: “(Litterfall OR litter fall OR litter-fall) AND (fruit OR flower OR seed OR reproductive) AND (leaf OR foliage OR needle) AND (NPP OR “net primary productivity”). This produced ~3,800 publications which were used as a starting point to find published estimates of NPP, ANPP, reproductive flux, and leaf litter fluxes. These data were converted to units of g C m-2 yr-1 and used to calculate the benchmarks R/L, R/ANPP, and R/NPP. Sites reporting only reproductive and leaf litter fluxes were identified by searching for publicly available litterfall databases and data papers. Data originally reported in units of dry biomass were converted to carbon assuming dry biomass is 50% carbon by weight. Species-level recruitment rates into the 1 cm size class were calculated from CTFS-ForestGeo census data at four sites using methods that account for unobserved mortality of new recruits between census intervals (see Kohyama et al., 2018, eqn 11). For consistency with model predictions, only “canopy trees” are included, which we define according to prior work (Powell et al., 2018) whereby any tree with the potential to reach a stature 20 cm dbh is included in the analysis. Palms (i.e. members of the family Arecaceae) were excluded from estimates. Tree census data used to produce recruitment rates came from a) the Barro Colorado Island (BCI) Forest Dynamics Plot (Hubbell et al., 2015), census observations between 1981-2016; b) the Luquillo Forest Dynamics Plot (Zimmerman et al., 2010), census observations between 1990-2016; c) the Smithsonian Conservation Biology Institute (SCBI) Forest Dynamics Plot (Bourg et al., 2013), census observations between 2008-2018; and d) the Smithsonian Environmental Research Center (SERC) Forest Dynamics Plot, census observations between 2008-2014 (McMahon & Parker, 2021). These sites cover tropical rain forest (BCI and Luquillo) and temperate seasonal forest (SCBI and SERC) Whittaker biomes.

Access Level: Public

Originating Institution(s): UC Berkeley; Lawrence Berkeley National Lab

Sponsor Organization(s): None

Contact: Hanbury-Brown, Adam - University of California Berkeley (ahanburybrown@gmail.com)

Version: 1.0

Dataset Citation: Ward R; Hanbury-Brown A; Kueppers L (2024): Model-ready benchmarks for NPP, ANPP, litter fluxes, and recruitment into the 1 cm dbh size class. 1.0. NGEE Tropics Data Collection. (dataset). http://dx.doi.org/10.15486/ngt/1862989

Acknowledgement: Hanbury-Brown, A.R., Ward, R.E. and Kueppers, L.M. (2022), Forest regeneration within Earth system models: current process representations and ways forward. New Phytologist. Accepted Author Manuscript. https://doi.org/10.1111/nph.18131

Data Link: Download Dataset

Bourg, N.A., W.J. McShea, J.R. Thompson, J.C. McGarvey, and X. Shen. 2013. Initial census, woody seedling, seed rain, and stand structure data for the SCBI SIGEO Large Forest Dynamics Plot. Ecology 94 (9): 2111-2112. http://dx.doi.org/10.1890/13-0010.1

Hubbell, S.P., Condit, R., and Foster, R.B. 2015. Barro Colorado Forest Census Plot Data. [WWW Document] URL http://ctfs.si.edu/webatlas/datasets/bci [accessed 17 Oct 2021].

Kohyama TS, Kohyama TI, Sheil D. 2018. Definition and estimation of vital rates from repeated censuses: Choices, comparisons and bias corrections focusing on trees. Methods in Ecology and Evolution 9: 809–821.

McMahon S., Parker, G. 2021. Smithsonian Environmental Research Center. [WWW Document] URL https://forestgeo.si.edu/sites/north-america/smithsonian-environmental-research-center [accessed 17 Oct 2021].

Powell TL, Koven CD, Johnson DJ, Faybishenko B, Fisher RA, Knox RG, McDowell NG, Condit R, Hubbell SP, Wright SJ, et al. 2018. Variation in hydroclimate sustains tropical forest biomass and promotes functional diversity. New Phytologist 219: 932–946.

Zimmerman, Jess K., Liza S. Comita, Jill Thompson, María Uriarte, and Nicholas Brokaw. 2010. Patch dynamics and community metastability of a subtropical forest: compound effects of natural disturbance and human land use. Landscape Ecology 25: 1099-1111