Cargando…

Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?

Soil organic carbon (SOC) changes associated with land conversion to energy crops are central to the debate on bioenergy and their potential carbon neutrality. Here, the experimental evidence on SOC under perennial energy crops (PECs) is synthesised to parameterise a whole systems model and to ident...

Descripción completa

Detalles Bibliográficos
Autores principales: Agostini, Francesco, Gregory, Andrew S., Richter, Goetz M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Springer US 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4732603/
https://www.ncbi.nlm.nih.gov/pubmed/26855689
http://dx.doi.org/10.1007/s12155-014-9571-0
_version_ 1782412728892129280
author Agostini, Francesco
Gregory, Andrew S.
Richter, Goetz M.
author_facet Agostini, Francesco
Gregory, Andrew S.
Richter, Goetz M.
author_sort Agostini, Francesco
collection PubMed
description Soil organic carbon (SOC) changes associated with land conversion to energy crops are central to the debate on bioenergy and their potential carbon neutrality. Here, the experimental evidence on SOC under perennial energy crops (PECs) is synthesised to parameterise a whole systems model and to identify uncertainties and knowledge gaps determining PECs being a sink or source of greenhouse gas (GHG). For Miscanthus and willow (Salix spp.) and their analogues (switchgrass, poplar), we examine carbon (C) allocation to above- and belowground residue inputs, turnover rates and retention in the soil. A meta-analysis showed that studies on dry matter partitioning and C inputs to soils are plentiful, whilst data on turnover are rare and rely on few isotopic C tracer studies. Comprehensive studies on SOC dynamics and GHG emissions under PECs are limited and subsoil processes and C losses through leaching remain unknown. Data showed dynamic changes of gross C inputs and SOC stocks depending on stand age. C inputs and turnover can now be specifically parameterised in whole PEC system models, whilst dependencies on soil texture, moisture and temperature remain empirical. In conclusion, the annual net SOC storage change exceeds the minimum mitigation requirement (0.25 Mg C ha(−1) year(−1)) under herbaceous and woody perennials by far (1.14 to 1.88 and 0.63 to 0.72 Mg C ha(−1) year(−1), respectively). However, long-term time series of field data are needed to verify sustainable SOC enrichment, as the physical and chemical stabilities of SOC pools remain uncertain, although they are essential in defining the sustainability of C sequestration (half-life >25 years).
format Online
Article
Text
id pubmed-4732603
institution National Center for Biotechnology Information
language English
publishDate 2015
publisher Springer US
record_format MEDLINE/PubMed
spelling pubmed-47326032016-02-04 Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out? Agostini, Francesco Gregory, Andrew S. Richter, Goetz M. Bioenergy Res Article Soil organic carbon (SOC) changes associated with land conversion to energy crops are central to the debate on bioenergy and their potential carbon neutrality. Here, the experimental evidence on SOC under perennial energy crops (PECs) is synthesised to parameterise a whole systems model and to identify uncertainties and knowledge gaps determining PECs being a sink or source of greenhouse gas (GHG). For Miscanthus and willow (Salix spp.) and their analogues (switchgrass, poplar), we examine carbon (C) allocation to above- and belowground residue inputs, turnover rates and retention in the soil. A meta-analysis showed that studies on dry matter partitioning and C inputs to soils are plentiful, whilst data on turnover are rare and rely on few isotopic C tracer studies. Comprehensive studies on SOC dynamics and GHG emissions under PECs are limited and subsoil processes and C losses through leaching remain unknown. Data showed dynamic changes of gross C inputs and SOC stocks depending on stand age. C inputs and turnover can now be specifically parameterised in whole PEC system models, whilst dependencies on soil texture, moisture and temperature remain empirical. In conclusion, the annual net SOC storage change exceeds the minimum mitigation requirement (0.25 Mg C ha(−1) year(−1)) under herbaceous and woody perennials by far (1.14 to 1.88 and 0.63 to 0.72 Mg C ha(−1) year(−1), respectively). However, long-term time series of field data are needed to verify sustainable SOC enrichment, as the physical and chemical stabilities of SOC pools remain uncertain, although they are essential in defining the sustainability of C sequestration (half-life >25 years). Springer US 2015-01-15 2015 /pmc/articles/PMC4732603/ /pubmed/26855689 http://dx.doi.org/10.1007/s12155-014-9571-0 Text en © The Author(s) 2015 https://creativecommons.org/licenses/by/4.0/ Open AccessThis article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.
spellingShingle Article
Agostini, Francesco
Gregory, Andrew S.
Richter, Goetz M.
Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title_full Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title_fullStr Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title_full_unstemmed Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title_short Carbon Sequestration by Perennial Energy Crops: Is the Jury Still Out?
title_sort carbon sequestration by perennial energy crops: is the jury still out?
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4732603/
https://www.ncbi.nlm.nih.gov/pubmed/26855689
http://dx.doi.org/10.1007/s12155-014-9571-0
work_keys_str_mv AT agostinifrancesco carbonsequestrationbyperennialenergycropsisthejurystillout
AT gregoryandrews carbonsequestrationbyperennialenergycropsisthejurystillout
AT richtergoetzm carbonsequestrationbyperennialenergycropsisthejurystillout