Data Set Citation:
When using this data, please cite the data package:
Zheng D and National Center for Ecological Analysis and Synthesis.
NPP Multi-Biome: Gridded Estimates for Selected Regions Worldwide, 1989-2001, R1
chadden.64.2 (https://knb.ecoinformatics.org:443/knb/metacat/chadden.64.2/nceas)
General Information:
Title:NPP Multi-Biome: Gridded Estimates for Selected Regions Worldwide, 1989-2001, R1
Identifier:chadden.64
Abstract:
Most field data for net primary productivity (NPP) are for relatively small field sites that are effectively points when considered at the 0.5 x 0.5 degree scale commonly used in global biogeochemical models. Thus, direct comparison between field data and coarse resolution model outputs can be misleading. Consistent estimates of NPP for 0.5x0.5 degree grid cells were developed from 15 studies representing NPP in croplands, sparse vegetation, shrublands, grasslands, and forests worldwide. The data set contains 3654 cells with a subset of 2335 cells in which outliers were removed and all replicate measurements were aggregated for each cell. The data set is a contribution to the Global Primary Production Data Initiative (GPPDI). Total NPP ranged from 3 gC/m2/yr for sparse vegetation to 1235 gC/m2/yr in forest, while aboveground NPP ranged from 3 to 890 gC/m2/yr (Zheng et al. 2003). Zheng et al. (2003) discuss the potential problems in such data-model inter-comparisons and identify issues that must be considered during the aggregation of field-scale data to coarser spatial resolutions, usually in the form of grid cells. They evaluated the data set by comparison with existing literature and the widely used Miami model. The file NPP_Gridded_3654_cells.csv is suitable for biome level and overall analyses because of larger sample size. The file NPP_Gridded_2335_unique_cells.csv was derived from the larger file; however, outliers were excluded, replicate measurements were averaged out for each unique geographic locations, and cells classified as water, bareground, and urban were excluded. It is more appropriate for model/data inter-comparisons.
Keywords:
  • net primary production
  • cropland
  • sparse vegetation
  • shrubland
  • grassland
  • forests
  • half degree grid cells

Involved Parties

Data Set Creators:
Individual: Daolan Zheng
Organization:Dept. of Earth, Ecological, and Environmental Sciences (EEES)
Address:
The University of Toledo Mail Stop 604,
2801 W. Bancroft St.,
Toledo, OH 43606
Phone:
1 419-530-2246 (voice)
Phone:
1 419-530-4421 (fax)
Email Address:
dzheng@utnet.utoledo.edu
Organization:National Center for Ecological Analysis and Synthesis
Data Set Contacts:
Individual: Daolan Zheng
Organization:Dept. of Earth, Ecological, and Environmental Sciences (EEES)
Address:
The University of Toledo Mail Stop 604,
2801 W. Bancroft St.,
Toledo, OH 43606
Phone:
1 419-530-2246 (voice)
Phone:
1 419-530-4421 (fax)
Email Address:
dzheng@utnet.utoledo.edu
Associated Parties:
Individual: S. D. Prince
Individual: R. Wright

Data Set Characteristics

Geographic Region:
Geographic Description:Consistent estimates of NPP for 0.5x0.5 degree grid cells were developed from 15 studies representing NPP in croplands, sparse vegetation, shrublands, grasslands, and forests worldwide.
Bounding Coordinates:
West:  -180.0  degrees
East:  180.0  degrees
North:  90.0  degrees
South:  -90.0  degrees
Time Period:
Begin:
1989-01-01
End:
2001-01-01

Sampling, Processing and Quality Control Methods

Step by Step Procedures
Step 1:  
Description:

Principal methods used for estimation of 0.5-degree cell NPP data in this study

1) stratification of grid cells and area weighting of field NPP observations in each stratum, 2) aggregation of finer-scale (plot or stand level) spatial inventory data, 3) local modeling of NPP using key environmental variables, for which maps are available, and 4) direct correlation of ground measurements with remotely sensed vegetation indices. Because many field observations are for components of NPP, where possible we have calculated missing components to provide consistent estimates of total NPP.

Data Set Usage Rights

no restrictions Cite this data set as follows: Zheng, D. L., S. D. Prince, and R. Wright. 2003. NPP Multi-Biome: Gridded Estimates for Selected Regions Worldwide, 1989-2001i, R1. Data set. Available on-line [http://www.daac.ornl.gov] from the Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A.
Access Control:
Auth System:knb
Order:denyFirst
Metadata download: Ecological Metadata Language (EML) File