Data Set Citation:
When using this data, please cite the data package:
NCEAS 6840 : Harmon: Analysis of long-term litter decomposition experiments , National Center for Ecological Analysis and Synthesis , and Harmon M. 2007.
Analysis of long-term litter decomposition experiments
nceas.328.26 (http://knb.ecoinformatics.org/knb/metacat/nceas.328.26/nceas)
General Information:
Title:Analysis of long-term litter decomposition experiments
Identifier:nceas.328
Abstract:
Although numerous short-term experiments have been used to develop conceptual and simulation models of decomposition, very little is known about the later stages of this process. Exclusion of this later stage has led, at best, to incomplete understanding of ecosystem carbon and nitrogen dynamics. This working group examined the wealth of litter and decomposition data that has been produced by several recent long-term field experiments. Our analysis will initially be based on data from LIDET (Long-term Intersite Decomposition Experiment Team), a 27-site experiment conducted over a 10-year period.
Keywords:None:
  • Wood
None:
  • Carbon
None:
  • Decay rates
None:
  • Decomposition
None:
  • Fine roots
None:
  • Leaf litter
None:
  • Litterfall
None:
  • Nitrogen
None:
  • Phosphorus
None:
  • Roots
Publication Date:2007-05-04
Data Table, Image, and Other Data Details:
Metadata download: Ecological Metadata Language (EML) File
Data Table:predicted_pafrm_using_model_outputs_L_R.csv ( View Metadata | Download File download)
Data Table:int_k_coeff_and_eqn_type_L_R.csv ( View Metadata | Download File download)
Data Table:int_k_coeff_eqn_and_final_values_wood.csv ( View Metadata | Download File download)
Data Table:predicted_pafrm_using_model_outputs_wood.csv ( View Metadata | Download File download)
Data Table:output_from_nlin_model_runs_L_R.csv ( View Metadata | Download File download)
Data Table:output_from_nlin_model_runs_wood_r2.csv ( View Metadata | Download File download)
Data Table:integrated_k_values_leaf_root.csv ( View Metadata | Download File download)

Involved Parties

Data Set Creators:
Organization:NCEAS 6840 : Harmon: Analysis of long-term litter decomposition experiments
Organization:National Center for Ecological Analysis and Synthesis
Individual: Mark Harmon
Organization:Oregon State University
Address:
Select state or territory here.
Email Address:
mark.harmon@oregonstate.edu
Data Set Contacts:
Individual: Mark Harmon
Organization:Oregon State University
Address:
Select state or territory here.
Email Address:
mark.harmon@oregonstate.edu
Metadata Providers:
Individual: Callie Bowdish

Data Set Characteristics

Geographic Region:
Geographic Description:Sites Ranging from British Columbia to Panama
Bounding Coordinates:
West:  -139.3308  degrees
East:  -79.8478  degrees
North:  59.8456  degrees
South:  9.1506  degrees
Time Period:
Begin:
1990
End:
2002

Sampling, Processing and Quality Control Methods

Step by Step Procedures
Step 1:  
Description:

Experiment Design

The major factors to be considered in this experiment will be site, species of and type of litter (leaves, vs. roots vs dowels), and time. Twenty-one sites, representing a wide array of moisture and temperature conditions, will be used for litter incubations. Ten types of 'standard' litters will be sent to each site. These include three types of fine roots (graminoid, hardwood, and conifer), six types of leaf litter (which range in lignin/nitrogen ratio from 5 to 75), and wooden dowels. Samples will be collected ten times; the time between samples will be one year for all sites except LaSelva and Luquillo which will collect samples every three months. There will be four replicates for each species, site and time.
Step 2:  
Description:

Equations used in SAS proc NLIN to model decomp. Rate (k), m0 (intercept), s0 (stable portion)

Input raw field data: MPAFRM=mean percent ashfree remaining mass

MTIMEOUT=years sample decomposed

Model 1 MPAFRM = (m0*EXP(-k*MTIMEOUT)); (no force intercept)

Model 2 MPAFRM = (m0*EXP(-k*mtimeout)); (forced intercept)

Model 3 MPAFRM = (m0*EXP(-k*TIMEout))+s0; (stable portion)

Model 4 MPAFRM = ((100 - s0)*EXP(-k*MTIMEOUT))+ s0; (stable portion forced intercept)

Model 5 MPAFRM = (m0f*EXP(-kf*MTIMEOUT))+(100-m0f)*exp(-ks*MTIMEOUT); (k fast and k slow, dual model)

Model 6 MPAFRM = (m0*EXP(-k*MTIMEOUT)); (last 4 years only)
Step 3:  
Description:

Integrated-k calculations

1. Calculate predicted remaining mass over long time period using best fit k and intercept from nlin output.

PredPAFRM = (M0F * exp(-KF*TIMEOUT)) + (100 - M0F) * exp(-KS * TIMEOUT);

run;

2. Sum the predicted masses

3. Calculate Integrated k: =100/sumpred*-1;
Sampling Area And Frequency:
The data used for analysis is from TD023 Intersite Fine litter Decomposition Experiment (LIDET) More information on the methods of collecting the data is at: http://www.fsl.orst.edu/lter/data/abstractdetail.cfm?dbcode=TD023&topnav=1
Sampling Description:
In addition to the standard litters, each site will be represented by a 'wildcard' litter which appears at one site for each sample collection. The purpose of the wildcard species is to verify the predictions from the standard species. There will be four replicates for each wildcard species, site and time.

Data Set Usage Rights

no restrictions
Access Control:
Auth System:knb
Order:denyFirst
Metadata download: Ecological Metadata Language (EML) File