Lajtha, K. 2013. Soil solution chemistry in Detrital Input and Removal Treatments (DIRT) from the Andrews Experimental Forest, 1999-2019 Long-Term Ecological Research Andrews Forest LTER Site. [Database]. Available: https://andrewsforest-stage.forestry.oregonstate.edu/data/fsdb-data-catalog/TN021 Accessed 2026-05-10.

The Detrital Input and Removal Treatment (DIRT) Project was established to assess how rates and sources of plant litter inputs influence accumulations or losses of organic matter in forest soils. DIRT employs chronic additions and exclusions of aboveground litter inputs and exclusion of root ingrowth to permanent plots at eight forested and two shrub/grass sites in the northern hemisphere to investigate how soil organic matter (SOM) dynamics are influenced by plant detrital inputs across ecosystem and soil types. The long-term DIRT study at the H.J. Andrews Experimental Forest was established in an old-growth forest stand on the valley floor and aims to address how detrital quality and quantity control soil organic matter accumulation and stabilization. The DIRT plots consist of treatments that double leaf litter, double woody debris inputs, exclude aboveground litter inputs, remove root inputs via trenching, or remove all organic matter inputs. We measured changes in soil solution chemistry with depth, and conducted long-term incubations of bulk soils from different treatments in order to elucidate effects of detrital inputs on the relative amounts and lability of different soil C pools. These data include various properties of the DIRT plots obtained during re-measurements at various intervals. C and N concentrations and content in soil, CO2 efflux, and soil solution chemistry are measured from bulk samples to 1 m depth, field respiration measurements, and lysimeters at 2 depths, respectively, and assessed at Oregon State University.

Temporal coverage: 1999-12-01 to 2011-04-15

Geographic coverage: N/A

Bounds: W N/A, E N/A, N N/A, S N/A

• Soil organic matter (SOM) is the terrestrial biosphere's largest pool of organic carbon and is an integral part of the global C cycle. Therefore, changes in SOM formation and decomposition due to climate change, land management, disturbance or other factors can feed back to the climate system to either sequester CO2 into organic forms or release it to the atmosphere. Despite its pivotal role in the global C cycle, the relative importance and linkages of the various biological, chemical and physical processes regulating SOM balances are not well understood. Although forests contain more than 3x the soil C (575 x 1015 g) of agricultural lands (180 x 1015 g), forest SOM dynamics and their relation to detrital inputs and soil biotic processing remain poorly understood. Even fundamental relationships, such as between mean annual temperature and SOM turnover rates, are controversial. A major challenge for environmental science is to develop a predictive understanding of how climate and vegetation interact to determine how detritus and soil biota affect SOM formation and stability. Over the years, our informal group of ecologists, biogeochemists and ecosystem modelers has been using a common set of experimental manipulations, referred to collectively as DIRT (Detritus Input and Removal Treatments), to assess how rates and sources of plant inputs control the accumulation and dynamics of SOM and nutrients in forest soils over decadal time scales. The original DIRT treatments consist of chronically altering plant inputs to forest soils by regularly removing surface litter from permanent plots and adding it to others. Our network of DIRT sites now includes four operational temperate forest sites. The central goal of the DIRT project is to assess how rates and sources of plant litter inputs control the accumulation and dynamics of organic matter and nutrients in forest soils over decadal time scales. The project examines processes at multiple levels, across decades and centuries, exploring the intricate interconnections of biology and chemistry that lead to the formation of humic materials over these hitherto unexplored long time spans. Our plots are part of an informal network of similar experimental treatments that span a significant climatic gradient and that encompass both coniferous and deciduous forests, and that vary widely in anthropogenic N loading. Current DIRT sites include Harvard Forest, MA (oak forest, established 1991); Bousson Experimental Research Reserve, PA (deciduous forest, established 1992); Sikfokut Forest, Hungary (turkey oak forest, established 2001), and the Michigan Biological Station, MI (pine forest, established 2004).

Title: Long-Term Ecological Research

• Kate Lajtha
  Role: Principal Investigator
  Oregon State University;Dept. of Botany and Plant Pathology;2059 Cordley Hall, Corvallis, OR, 97331, USA
  Phone: (541) 737-5674
  Email: lajthak@science.oregonstate.edu
  URL: http://cropandsoil.oregonstate.edu/content/kate-lajtha
• Derek Pierson
  Role: Other Researcher
  Email: piersond@oregonstate.edu
• Phillip Sollins
  Role: Other Researcher
  Emeritus, Oregon State University;Forest Ecosystems & Society, Corvallis, OR, 97331-5752, USA
  Phone: (541) 737-6582
  Email: phil.sollins@oregonstate.edu
• Hayley Peter-Contesse
  Role: Other Researcher
  Email: petercoh@oregonstate.edu
• April Strid
  Role: Other Researcher
• Fox Sparky Peterson
  Role: Other Researcher
  Phone: 404-580-5016
  Email: fox@tinybike.net
• Jennifer Dawn Wig
  Role: Other Researcher
  Forest Ecosystems and Society
• Kim Townsend
  Role: Other Researcher
  Botany and Plant Pathology;Oregon State University, Corvallis, OR, 97331, USA
  Email: townseki@oregonstate.edu, zoeykim@aol.com
• Kate Lajtha
  Role: Creator
  Oregon State University;Dept. of Botany and Plant Pathology;2059 Cordley Hall, Corvallis, OR, 97331, USA
  Phone: (541) 737-5674
  Email: lajthak@science.oregonstate.edu
  URL: http://cropandsoil.oregonstate.edu/content/kate-lajtha

• Information Manager
  Andrews Forest LTER Program, US Forest Service Pacific Northwest Research Station, 3200 SW Jefferson Way, Corvallis, OR, 97331
  Email: hjaweb@fsl.orst.edu
  URL: http://andrewsforest.oregonstate.edu/
• Fox Sparky Peterson
  Phone: 404-580-5016
  Email: fox@tinybike.net

• Andrews Forest LTER Site
  Role: Publisher
  Forest Ecosystems and Society Department in Forestry, Oregon State University, 201K Richardson Hall, Corvallis, OR, 97331-5752
  Phone: (541) 737-8480
  Email: lterweb@fsl.orst.edu
  URL: http://andrewsforest.oregonstate.edu/

The Detrital Input and Removal Treatment (DIRT) Project was established to assess how rates and sources of plant litter inputs influence accumulations or losses of organic matter in forest soils. DIRT employs chronic additions and exclusions of aboveground litter inputs and exclusion of root ingrowth to permanent plots at eight forested and two shrub/grass sites in the northern hemisphere to investigate how soil organic matter (SOM) dynamics are influenced by plant detrital inputs across ecosystem and soil types. The long-term DIRT study at the H.J. Andrews Experimental Forest was established in an old-growth forest stand on the valley floor and aims to address how detrital quality and quantity control soil organic matter accumulation and stabilization. The DIRT plots consist of treatments that double leaf litter, double woody debris inputs, exclude aboveground litter inputs, remove root inputs via trenching, or remove all organic matter inputs. We measured changes in soil solution chemistry with depth, and conducted long-term incubations of bulk soils from different treatments in order to elucidate effects of detrital inputs on the relative amounts and lability of different soil C pools. These data include various properties of the DIRT plots obtained during re-measurements at various intervals. C and N concentrations and content in soil, CO2 efflux, and soil solution chemistry are measured from bulk samples to 1 m depth, field respiration measurements, and lysimeters at 2 depths, respectively, and assessed at Oregon State University. Soil organic matter (SOM) is the terrestrial biosphere's largest pool of organic carbon and is an integral part of the global C cycle. Therefore, changes in SOM formation and decomposition due to climate change, land management, disturbance or other factors can feed back to the climate system to either sequester CO2 into organic forms or release it to the atmosphere. Despite its pivotal role in the global C cycle, the relative importance and linkages of the various biological, chemical and physical processes regulating SOM balances are not well understood. Although forests contain more than 3x the soil C (575 x 1015 g) of agricultural lands (180 x 1015 g), forest SOM dynamics and their relation to detrital inputs and soil biotic processing remain poorly understood. Even fundamental relationships, such as between mean annual temperature and SOM turnover rates, are controversial. A major challenge for environmental science is to develop a predictive understanding of how climate and vegetation interact to determine how detritus and soil biota affect SOM formation and stability. Over the years, our informal group of ecologists, biogeochemists and ecosystem modelers has been using a common set of experimental manipulations, referred to collectively as DIRT (Detritus Input and Removal Treatments), to assess how rates and sources of plant inputs control the accumulation and dynamics of SOM and nutrients in forest soils over decadal time scales. The original DIRT treatments consist of chronically altering plant inputs to forest soils by regularly removing surface litter from permanent plots and adding it to others. Our network of DIRT sites now includes four operational temperate forest sites. The central goal of the DIRT project is to assess how rates and sources of plant litter inputs control the accumulation and dynamics of organic matter and nutrients in forest soils over decadal time scales. The project examines processes at multiple levels, across decades and centuries, exploring the intricate interconnections of biology and chemistry that lead to the formation of humic materials over these hitherto unexplored long time spans. Our plots are part of an informal network of similar experimental treatments that span a significant climatic gradient and that encompass both coniferous and deciduous forests, and that vary widely in anthropogenic N loading. Current DIRT sites include Harvard Forest, MA (oak forest, established 1991); Bousson Experimental Research Reserve, PA (deciduous forest, established 1992); Sikfokut Forest, Hungary (turkey oak forest, established 2001), and the Michigan Biological Station, MI (pine forest, established 2004). Field Methods - TN021

Purpose: Soil organic matter (SOM) is the terrestrial biosphere's largest pool of organic carbon and is an integral part of the global C cycle. Therefore, changes in SOM formation and decomposition due to climate change, land management, disturbance or other factors can feed back to the climate system to either sequester CO2 into organic forms or release it to the atmosphere. Despite its pivotal role in the global C cycle, the relative importance and linkages of the various biological, chemical and physical processes regulating SOM balances are not well understood. Although forests contain more than 3x the soil C (575 x 1015 g) of agricultural lands (180 x 1015 g), forest SOM dynamics and their relation to detrital inputs and soil biotic processing remain poorly understood. Even fundamental relationships, such as between mean annual temperature and SOM turnover rates, are controversial. A major challenge for environmental science is to develop a predictive understanding of how climate and vegetation interact to determine how detritus and soil biota affect SOM formation and stability. Over the years, our informal group of ecologists, biogeochemists and ecosystem modelers has been using a common set of experimental manipulations, referred to collectively as DIRT (Detritus Input and Removal Treatments), to assess how rates and sources of plant inputs control the accumulation and dynamics of SOM and nutrients in forest soils over decadal time scales. The original DIRT treatments consist of chronically altering plant inputs to forest soils by regularly removing surface litter from permanent plots and adding it to others. Our network of DIRT sites now includes four operational temperate forest sites. The central goal of the DIRT project is to assess how rates and sources of plant litter inputs control the accumulation and dynamics of organic matter and nutrients in forest soils over decadal time scales. The project examines processes at multiple levels, across decades and centuries, exploring the intricate interconnections of biology and chemistry that lead to the formation of humic materials over these hitherto unexplored long time spans. Our plots are part of an informal network of similar experimental treatments that span a significant climatic gradient and that encompass both coniferous and deciduous forests, and that vary widely in anthropogenic N loading. Current DIRT sites include Harvard Forest, MA (oak forest, established 1991); Bousson Experimental Research Reserve, PA (deciduous forest, established 1992); Sikfokut Forest, Hungary (turkey oak forest, established 2001), and the Michigan Biological Station, MI (pine forest, established 2004).

Method Steps

Sampling

No software entries listed in this EML file.

• LTER controlled vocabulary: biogeochemistry (theme), decomposition (theme), carbon cycling (theme), litterfall (theme), nutrients (theme), terrestrial ecosystems (theme)

• All Organisms: All Organisms
• Highest common category (ca. kingdom): Plantae
• Division or Phylum: Coniferophyta
• Class: Pinopsida
• Order: Pinales
• Family: Pinaceae
• Genus: Tsuga
• Species: Tsuga heterophylla
• Genus: Pseudotsuga
• Species: Pseudotsuga menziesii

No related dataset codes found in the EML text fields.

• Yano, Yuriko; Lajtha, Kate; Sollins, Phillip; Caldwell, Bruce A. 2004. Chemical and seasonal controls on the dynamics of dissolved organic matter in a coniferous old-growth stand in the Pacific Northwest, USA. Biogeochemistry. 71: 197-223.
• Sulzman, Elizabeth W.; Brant, Justin B.; Bowden, Richard D.; Lajtha, Kate. 2005. Contribution of aboveground litter, belowground litter, and rhizosphere respiration to total soil CO2 efflux in an old growth coniferous forest. Biogeochemistry. 73: 231-256.
• Lajtha, K.; Crow, S. E.; Yano, Y.; Kaushal, S. S.; Sulzman, E.; Sollins, P.; Spears, J. D. H. 2005. Detrital controls on soil solution N and dissolved organic matter in soils: a field experiment. Biogeochemistry. 76: 261-281.
• Spears, J. D. H.; Lajtha, K. 2004. The imprint of coarse woody debris on soil chemistry in the western Oregon Cascades. Biogeochemistry. 71: 163-175.
• Holub, Scott M.; Lajtha, Kate; Spears, Julie D. H.; Tóth, János A.; Crow, Susan E.; Caldwell, Bruce A.; Papp, Mária; Nagy, Péter T. 2005. Organic matter manipulations have little effect on gross and net nitrogen transformations in two temperate forest mineral soils in the USA and central Europe. Forest Ecology and Management. 214: 320-330.
• Crow, Susan E.; Sulzman, Elizabeth W.; Rugh, William D.; Bowden, Richard D.; Lajtha, Kate. 2006. Isotopic analysis of respired CO2 during decomposition of separated soil organic matter pools. Soil Biology and Biochemistry. 38: 3279-3291.
• Brant, Justin. 2005. Controls of microbial community composition and function in forest soils. Corvallis, OR: Oregon State University. 105 p. M.S. thesis.
• Sollins, Phillip; Swanston, Christopher; Kleber, Markus; Filley, Timothy; Kramer, Marc; Crow, Susan; Caldwell, Bruce A.; Lajtha, Kate; Bowden, Richard. 2006. Organic C and N stabilization in a forest soil: evidence from sequential density fractionation. Soil Biology and Biochemistry. 38: 3313-3324.
• Brant, Justin B.; Sulzman, Elizabeth W.; Myrold, David D. 2006. Microbial community utilization of added carbon substrates in response to long-term carbon input manipulation. Soil Biology and Biochemistry. 38 : 2219-2232.
• Brant, Justin B.; Myrold, David D.; Sulzman, Elizabeth W. 2006. Root controls on soil microbial community structure in forest soils. Oecologia. 148(4): 650-659.
• Crow, Susan E.; Swanston, Christopher W.; Lajtha, Kate; Brooks, J. Renée; Keirstead, Heath. 2007. Density fractionation of forest soils: methodological questions and interpretation of incubation results and turnover time in an ecosystem context. Biogeochemistry. 85: 69-90.
• Crow, Susan E. 2006. Characteristics of soil organic matter in two forest soils. Corvallis, OR: Oregon State University. Ph.D. dissertation.
• Yarwood, Stephanie; Brewer, Elizabeth; Yarwood, Rockie; Lajtha, Kate; Myrold, David. 2013. Soil Microbe Active Community Composition and Capability of Responding to Litter Addition after 12 Years of No Inputs. Applied and Environmental Microbiology. 79(4): 1385-1392.
• Strid, April; Lee, Baek Soo; Lajtha, Kate. 2016. Homogenization of detrital leachate in an old-growth coniferous forest, OR: DOC fluorescence signatures in soils undergoing long-term litter manipulations. Plant and Soil. 408(1): 133-148. doi: 10.1007/s11104-016-2914-1
• Lajtha, Kate; Bowden, Richard D.; Crow, Susan; Fekete, Istvan; Kotroczo, Zsolt; Plante, Alain; Simpson, Myrna J.; Nadelhoffer, Knute J. 2018. The detrital input and removal treatment (DIRT) network: Insights into soil carbon stabilization. Science of The Total Environment. 640-641: 1112-1120. doi: doi.org/10.1016/j.scitotenv.2018.05.388

• The Detrital Input and Removal Experiment (DIRT) network website
  a link to the DIRT website
  URL: https://dirtnet.wordpress.com/
• HJA DIRT plots
  Spatial representation of the DIRT plots with numbering from John Dixon
  URL: https://andrewsforest.oregonstate.edu/data/studies/tn021/dirt_plot_numbering.png

Data Use Agreement:

The re-use of scientific data has the potential to greatly increase communication, collaboration and synthesis within and among disciplines, and thus is fostered, supported and encouraged. This Data Set is released under the Creative Commons license CC BY "Attribution" (see: https://creativecommons.org/licenses/by/4.0/). Creative Commons license CC BY - Attribution is a license that allows others to distribute, remix, tweak, and build upon your work (even commercially), as long as you are credited for the original creation. This license accommodates maximum dissemination and use of licensed materials.

It is considered professional conduct and an ethical obligation to acknowledge the work of other scientists. The Data User is asked to provide attribution of the original work if this data package is shared in whole or by individual parts or used in the derivation of other products. A recommended citation is provided for each Data Set in the Andrews LTER data catalog (see: http://andlter.forestry.oregonstate.edu/data/catalog/datacatalog.aspx). A generic citation is also provided for this Data Set on the website https://portal.edirepository.org in the summary metadata page. Data Users are thus strongly encouraged to consider consultation, collaboration and/or co-authorship with the Data Set Creator.

While substantial efforts are made to ensure the accuracy of data and associated documentation, complete accuracy of data sets cannot be guaranteed and all data are made available "as is." The Data User should be aware, however, that data are updated periodically and it is the responsibility of the Data User to check for new versions of the data. The data authors and the repository where these data were obtained shall not be liable for damages resulting from any use or misinterpretation of the data.

General acknowledgement: Data were provided by the HJ Andrews Experimental Forest research program, funded by the National Science Foundation's Long-Term Ecological Research Program (DEB 2025755), US Forest Service Pacific Northwest Research Station, and Oregon State University.

License: N/A

Maintenance update frequency: irregular

Description

• An update history is logged and maintained with each new version of every dataset.

Change History

• Version1 (2012-08-03)
  Study code and preliminary metadata established
• Version2 (2013-01-03)
  uploaded metadata and data from XLS spreadsheets for all 5 entities. Ran QC. Uploaded data to SQL.