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Yin S, Wei C, Qu X, Fu H, Li B, Piao S, Tao S, Hatcher PG, Zhu D. Benzenepoly(carboxylic acid)s as Exclusive Intrinsic Markers to Assess Riverine Export of Dissolved Black Carbon. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1142-1151. [PMID: 38159290 DOI: 10.1021/acs.est.3c05988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Landscape fires annually generate large quantities of black carbon. The water-soluble fraction of black carbon (i.e., dissolved black carbon/DBC) is an important constituent of the dissolved organic carbon (DOC) pool, playing a crucial role in the global budget of refractory carbon and climate change. A key challenge in constraining the flux and fate of riverine DBC is to develop targeted and accurate quantification methods. Herein, we report that benzenepentacarboxylic acid (B5CA) intrinsically present in DBC can be used as an exclusive and holistic marker (representing both condensed aromatics and less-/nonaromatic fractions) for DBC quantification. B5CA was universally detected in water extractions of biochar and fire-affected soils with relatively large abundance but not produced by nonthermogenic processes. It has good mobility in the environment as it is not readily precipitated by cations or adsorbed by common geosorbents. B5CA also represents the recalcitrant components of DBC with excellent stability against photodegradation and biodegradation. Applying B5CA as the DBC marker in surface waters of the Changjiang River (i.e., the third largest river in the world), we calculate the DBC concentration in the downstream Changjiang River to be 4.8 ± 5.5% of the DOC flux. Our work provides a simple and reliable approach for the accurate quantification and source tracking of DBC in the soil and aquatic carbon pools.
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Affiliation(s)
- Shujun Yin
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Chenhui Wei
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Xiaolei Qu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Heyun Fu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Bengang Li
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Shilong Piao
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Shu Tao
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Patrick G Hatcher
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, West Virginia 23529, United States
| | - Dongqiang Zhu
- Key Laboratory of the Ministry of Education for Earth Surface Processes, School of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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Li H, Zhang R, Yan A, Xie W, Wang M, Yu K. Black Carbon in Deep-Sea Seamount Sediment Cores: Vertical Variation and Non-negligible Char Black Carbon. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:14602-14610. [PMID: 37713478 DOI: 10.1021/acs.est.3c04208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/17/2023]
Abstract
Deep-sea sediments (>1000 m) are often considered to be the ultimate sink for black carbon (BC), and the long-term buried BC in these sediments is believed to potentially provide a negative feedback effect on climate warming. The burial flux of BC in marine sediments is predominantly estimated based on soot BC (SBC) in most studies, frequently ignoring the contribution of char BC (CBC). While this methodology may result in an underestimation of the BC burial flux, the precise extent of this underestimation is yet to be determined. This study used the benzene poly(carboxylic acid) (BPCA) method and chemothermal oxidation (CTO) method to analyze CBC and SBC in four deep-sea sediment cores from the Zhongnan seamount in the South China Sea, respectively. The CBC content increased from 0.026 ± 0.010% at the seamount upper part (1432 m) to 0.039 ± 0.012% at the seamount foot (4278 m), constituting approximately 25 to 42% of the SBC content. The content disparity between CBC and SBC diminishes as depth increases. In deep-sea sediments, biogeochemical factors influence the variation of CBC molecules with depth. In the seamount middle-upper part (1432 and 2465 m), highly condensed CBC gradually accumulated along the core downward profile. In the sediment core profile of the seamount middle-lower part (3497 m), benzenetricarboxylic acid and benzenetetracarboxylic acid content decreased while the BC condensation degree rose, i.e., less condensed CBC was preferentially consumed. Afterward, CBC molecules reached a relatively stable state at the seamount foot. This study reveals that CBC possesses the capacity for long-term carbon sequestration in deep-sea sediments, and its content is not negligible.
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Affiliation(s)
- Haolan Li
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Ruijie Zhang
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China
| | - Annan Yan
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Wei Xie
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China
| | - Mengyuan Wang
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China
| | - Kefu Yu
- Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Coral Reef Research Center of China, School of Marine Sciences, Guangxi University, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519080, China
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Zosso CU, Ofiti NOE, Torn MS, Wiesenberg GLB, Schmidt MWI. Rapid loss of complex polymers and pyrogenic carbon in subsoils under whole-soil warming. NATURE GEOSCIENCE 2023; 16:344-348. [PMID: 37064011 PMCID: PMC10089920 DOI: 10.1038/s41561-023-01142-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 02/07/2023] [Indexed: 06/19/2023]
Abstract
Subsoils contain more than half of soil organic carbon (SOC) and are expected to experience rapid warming in the coming decades. Yet our understanding of the stability of this vast carbon pool under global warming is uncertain. In particular, the fate of complex molecular structures (polymers) remains debated. Here we show that 4.5 years of whole-soil warming (+4 °C) resulted in less polymeric SOC (sum of specific polymers contributing to SOC) in the warmed subsoil (20-90 cm) relative to control, with no detectable change in topsoil. Warming stimulated the subsoil loss of lignin phenols (-17 ± 0%) derived from woody plant biomass, hydrolysable lipids cutin and suberin, derived from leaf and woody plant biomass (-28 ± 3%), and pyrogenic carbon (-37 ± 8%) produced during incomplete combustion. Given that these compounds have been proposed for long-term carbon sequestration, it is notable that they were rapidly lost in warmed soils. We conclude that complex polymeric carbon in subsoil is vulnerable to decomposition and propose that molecular structure alone may not protect compounds from degradation under future warming.
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Affiliation(s)
- Cyrill U. Zosso
- Department of Geography, University of Zurich, Zurich, Switzerland
| | | | - Margaret S. Torn
- Climate Sciences Department, Lawrence Berkeley National Laboratory, Berkeley, CA USA
- Energy Resources Group, University of California, Berkeley, CA USA
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Sun Y, Tang J, Mo Y, Geng X, Zhong G, Yi X, Yan C, Li J, Zhang G. Polycyclic Aromatic Carbon: A Key Fraction Determining the Light Absorption Properties of Methanol-Soluble Brown Carbon of Open Biomass Burning Aerosols. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15724-15733. [PMID: 34806878 DOI: 10.1021/acs.est.1c06460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The composition and radiative forcing of light-absorbing brown carbon (BrC) aerosol remain poorly understood. Polycyclic aromatics (PAs) are BrC chromophores with fused benzene rings. Understanding the occurrence and significance of PAs in BrC is challenging due to a lack of standards for many PAs. In this study, we quantified polycyclic aromatic carbon (PAC), defined as the carbon of fused benzene rings, based on molecular markers (benzene polycarboxylic acids, BPCAs). Open biomass burning aerosols (OBBAs) of 22 rainforest plants were successively extracted with water and methanol for the analysis of water- and methanol-soluble PAC (WPAC and MPAC, respectively). PAC is an important fraction of water- and methanol-soluble organic carbon (WSOC and MSOC, respectively). WPAC/WSOC ranged from 0.03 to 0.18, and MPAC/MSOC was even higher (range: 0.16-0.80). The priority polycyclic aromatic hydrocarbons contributed less than 1% of MPAC. The mass absorption efficiency (MAE) of MSOC showed a strong linear correlation with MPAC/MSOC (r = 0.60-0.95, p < 0.01). The absorption Ångström exponent (AAE) of methanol-soluble BrC showed a strong linear correlation with the degree of aromatic condensation of MPAC, which was described by the average number of carboxylic groups of BPCA (r = -0.79, p < 0.01). This result suggested that PAC was a key fraction determining the light absorption properties (i.e., light absorptivity and wavelength dependence) of methanol-soluble BrC in OBBAs.
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Affiliation(s)
- Yue Sun
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jiao Tang
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
| | - Yangzhi Mo
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
| | - Xiaofei Geng
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
- Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment of the People's Republic of China, 210042 Nanjing, China
| | - Guangcai Zhong
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
| | - Xin Yi
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Qingdao 266000, P. R. China
| | - Jun Li
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong-Hongkong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, P. R. China
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5
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Vaezzadeh V, Yi X, Rais FR, Bong CW, Thomes MW, Lee CW, Zakaria MP, Wang AJ, Zhong G, Zhang G. Distribution of black carbon and PAHs in sediments of Peninsular Malaysia. MARINE POLLUTION BULLETIN 2021; 172:112871. [PMID: 34428623 DOI: 10.1016/j.marpolbul.2021.112871] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 08/08/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
Concentrations, sources and interactions between black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) were investigated in 42 sediment samples collected from riverine, coastal and shelf areas in Peninsular Malaysia. The concentrations of BC measured by benzene polycarboxylic acid (BPCA) method and PAHs showed broad spatial variations between the relatively pristine environment of the East coast and developed environment of the West and South coast ranging from 0.02 to 0.36% dw and 57.7 ng g-1 dw to 19,300 ng g-1 dw, respectively. Among diagnostic ratios of PAHs, the ratios of Ant/(Ant+Phe) and LMW/HMW drew the clearest distinctions between the East coast versus the West and South coast sediments indicating the predominance of petrogenic sources in the former versus pyrogenic sources in the latter. PAHs significantly correlated with BC and total organic carbon (TOC) in the sediments (p < 0.05) having similar correlation coefficients. BC accounted for 6.06 to 30.6% of TOC in sediments.
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Affiliation(s)
- Vahab Vaezzadeh
- State Key Laboratory of Organic Geochemistry and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China; Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Xin Yi
- State Key Laboratory of Organic Geochemistry and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Farah Rasyidah Rais
- Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute for Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chui Wei Bong
- Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia; Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - Margaret William Thomes
- Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute for Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Choon Weng Lee
- Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia; Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Mohamad Pauzi Zakaria
- Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Ai Jun Wang
- Laboratory for Coast and Ocean Geology, Third Institute of Oceanography (TIO), Ministry of Natural Resources, Xiamen 361005, China
| | - Guangcai Zhong
- State Key Laboratory of Organic Geochemistry and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China.
| | - Gan Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Center for Excellence in Deep Earth Science, Guangzhou 510640, China
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6
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Coppola AI, Seidel M, Ward ND, Viviroli D, Nascimento GS, Haghipour N, Revels BN, Abiven S, Jones MW, Richey JE, Eglinton TI, Dittmar T, Schmidt MWI. Marked isotopic variability within and between the Amazon River and marine dissolved black carbon pools. Nat Commun 2019; 10:4018. [PMID: 31488815 PMCID: PMC6728373 DOI: 10.1038/s41467-019-11543-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 07/11/2019] [Indexed: 11/29/2022] Open
Abstract
Riverine dissolved organic carbon (DOC) contains charcoal byproducts, termed black carbon (BC). To determine the significance of BC as a sink of atmospheric CO2 and reconcile budgets, the sources and fate of this large, slow-cycling and elusive carbon pool must be constrained. The Amazon River is a significant part of global BC cycling because it exports an order of magnitude more DOC, and thus dissolved BC (DBC), than any other river. We report spatially resolved DBC quantity and radiocarbon (Δ14C) measurements, paired with molecular-level characterization of dissolved organic matter from the Amazon River and tributaries during low discharge. The proportion of BC-like polycyclic aromatic structures decreases downstream, but marked spatial variability in abundance and Δ14C values of DBC molecular markers imply dynamic sources and cycling in a manner that is incongruent with bulk DOC. We estimate a flux from the Amazon River of 1.9–2.7 Tg DBC yr−1 that is composed of predominately young DBC, suggesting that loss processes of modern DBC are important. Black carbon produced by the burning of biomass and fuels is the most stable carbon compound in nature, yet its path from land to the deep ocean where it persists for thousands of years remains mysterious. Here Coppola and colleagues characterize the black carbon exported by the Amazon River, the largest river in the world.
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Affiliation(s)
- Alysha I Coppola
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.
| | - Michael Seidel
- Research Group for Marine Geochemistry, Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, D-26129, Oldenburg, Germany
| | - Nicholas D Ward
- Marine Sciences Laboratory, Pacific Northwest National Laboratory, 1529 West Sequim Bay Road, Sequim, WA, 98382, USA.,School of Oceanography, University of Washington, Box 355351, Seattle, WA, 98195, USA
| | - Daniel Viviroli
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Gabriela S Nascimento
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.,Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Negar Haghipour
- Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland.,Laboratory of Ion Beam Physics, ETH Zürich, Otto-Stern-Weg 5, 8093, Zürich, Switzerland
| | - Brandi N Revels
- Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Samuel Abiven
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Matthew W Jones
- Tyndall Centre for Climate Change Research, School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - Jeffrey E Richey
- School of Oceanography, University of Washington, Box 355351, Seattle, WA, 98195, USA
| | - Timothy I Eglinton
- Geological Institute, Department of Earth Sciences, ETH Zürich, Sonneggstrasse 5, 8092, Zürich, Switzerland
| | - Thorsten Dittmar
- Research Group for Marine Geochemistry, Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, D-26129, Oldenburg, Germany.,Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Ammerländer Heerstraße 231, 26129, Oldenburg, Germany
| | - Michael W I Schmidt
- Department of Geography, University of Zurich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
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Matosziuk LM, Alleau Y, Kerns BK, Bailey J, Johnson MG, Hatten JA. Effects of season and interval of prescribed burns on pyrogenic carbon in ponderosa pine stands in the southern Blue Mountains, Oregon, USA. GEODERMA 2019; 348:1-11. [PMID: 34795456 PMCID: PMC8597831 DOI: 10.1016/j.geoderma.2019.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In ponderosa pine (Pinus ponderosa) forests of the western United States, prescribed burns are used to reduce fuel loads and restore historical fire regimes. The season of and interval between burns can have complex consequences for the ecosystem, including the production of pyrogenic carbon (PyC). PyC plays a crucial role in soil carbon cycling, displaying turnover times that are orders of magnitude longer than unburned organic matter. This work investigated how the season of and interval between prescribed burns affect soil organic matter, including the formation and retention of PyC, in a ponderosa pine forest of eastern Oregon. In 1997 a prescribed burn study was implemented in Malheur National Forest to examine the ecological effects of burning at 5 and 15-year intervals in either the spring or fall. In October 2015, both O-horizon and mineral soil (0-15 cm) samples were collected and analyzed for PyC concentration, content, and structure using the benzene polycarboxylic acid (BPCA) method. O-horizon depth, carbon and nitrogen concentration and content, pH, and bulk density were also measured. Plots burned in the spring and fall had lower C and N stocks in the O-horizon compared to the unburned controls due to a reduction in O-horizon depth; however, we did not observe any differences in O-horizon concentration of C or N. Moreover, the concentration and stock of C and N in the mineral soil of plots burned in the spring or fall was the same as or only very slightly different from the unburned controls, suggesting that the prescribed burns on these sites have not adversely affected SOM quantity. Compared to unburned controls, we estimate that fall burns increased the mean PyC concentration of the mineral soil by 8.42 g BPCA/kg C. We did not detect a difference in mean PyC concentration of the mineral soil between the spring burns and the unburned controls; however, the spring burn plots did contain a number of isolated pockets with very high concentrations of PyC, suggesting a patchier burn pattern for these plots. In general, there was no detectable difference in any of the response variables when comparing the various prescribed burn treatments to one another. The disturbance caused by the reintroduction of fire to this ecosystem may have obscured subtle differences caused by the different seasons and intervals of burn that could become more apparent over time.
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Affiliation(s)
- Lauren M Matosziuk
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, Oregon, 97331
| | - Yvan Alleau
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, Oregon, 97331
| | - Becky K Kerns
- USDA Forest Service, Pacific Northwest Research Station, Corvallis Forestry Sciences Lab, Corvallis, Oregon, 97331
| | - John Bailey
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, Oregon, 97331
| | - Mark G Johnson
- U.S. Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Western Ecology Division, Corvallis, Oregon, 97333
| | - Jeff A Hatten
- Department of Forest Engineering, Resources, and Management, Oregon State University, Corvallis, Oregon, 97331
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