Grasslands may be more reliable carbon sinks than forests in California
Although natural terrestrial ecosystems have sequestered ~25% of anthropogenic CO _2 emissions, the long-term sustainability of this key ecosystem service is under question. Forests have traditionally been viewed as robust carbon (C) sinks; however, extreme heat-waves, drought and wildfire have incr...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2018-01-01
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| Series: | Environmental Research Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.1088/1748-9326/aacb39 |
| _version_ | 1797748239887237120 |
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| author | Pawlok Dass Benjamin Z Houlton Yingping Wang David Warlind |
| author_facet | Pawlok Dass Benjamin Z Houlton Yingping Wang David Warlind |
| author_sort | Pawlok Dass |
| collection | DOAJ |
| description | Although natural terrestrial ecosystems have sequestered ~25% of anthropogenic CO _2 emissions, the long-term sustainability of this key ecosystem service is under question. Forests have traditionally been viewed as robust carbon (C) sinks; however, extreme heat-waves, drought and wildfire have increased tree mortality, particularly in widespread semi-arid regions, which account for ~41% of Earth’s land surface. Using a set of modeling experiments, we show that California grasslands are a more resilient C sink than forests in response to 21st century changes in climate, with implications for designing climate-smart Cap and Trade offset policies. The resilience of grasslands to rising temperatures, drought and fire, coupled with the preferential banking of C to belowground sinks, helps to preserve sequestered terrestrial C and prevent it from re-entering the atmosphere. In contrast, California forests appear unable to cope with unmitigated global changes in the climate, switching from substantial C sinks to C sources by at least the mid-21st century. These results highlight the inherent risk of relying on forest C offsets in the absence of management interventions to avoid substantial fire-driven C emissions. On the other hand, since grassland environments, including tree-sparse rangelands, appear more capable of maintaining C sinks in 21st century, such ecosystems should be considered as an alternative C offset to climate-vulnerable forests. The further development of climate-smart approaches in California’s carbon marketplace could serve as an example to offset programs around the world, particularly those expanding into widespread arid and semi-arid regions. |
| first_indexed | 2024-03-12T16:02:04Z |
| format | Article |
| id | doaj.art-dea5c3a1439847a6af10387e0f899334 |
| institution | Directory Open Access Journal |
| issn | 1748-9326 |
| language | English |
| last_indexed | 2024-03-12T16:02:04Z |
| publishDate | 2018-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | Environmental Research Letters |
| spelling | doaj.art-dea5c3a1439847a6af10387e0f8993342023-08-09T14:35:31ZengIOP PublishingEnvironmental Research Letters1748-93262018-01-0113707402710.1088/1748-9326/aacb39Grasslands may be more reliable carbon sinks than forests in CaliforniaPawlok Dass0https://orcid.org/0000-0003-3957-4055Benjamin Z Houlton1https://orcid.org/0000-0002-1414-0261Yingping Wang2https://orcid.org/0000-0002-4614-6203David Warlind3Department of Land , Air and Water Resources, University of California, Davis, United States of America; Author to whom any correspondence should be addressed.Department of Land , Air and Water Resources, University of California, Davis, United States of America; John Muir Institute of the Environment , University of California, Davis, United States of AmericaCSIRO Oceans and Atmosphere , Private Bag 1, Aspendale, VIC 3195, AustraliaDepartment of Physical Geography and Ecosystem Science , Lund University, Lund, SwedenAlthough natural terrestrial ecosystems have sequestered ~25% of anthropogenic CO _2 emissions, the long-term sustainability of this key ecosystem service is under question. Forests have traditionally been viewed as robust carbon (C) sinks; however, extreme heat-waves, drought and wildfire have increased tree mortality, particularly in widespread semi-arid regions, which account for ~41% of Earth’s land surface. Using a set of modeling experiments, we show that California grasslands are a more resilient C sink than forests in response to 21st century changes in climate, with implications for designing climate-smart Cap and Trade offset policies. The resilience of grasslands to rising temperatures, drought and fire, coupled with the preferential banking of C to belowground sinks, helps to preserve sequestered terrestrial C and prevent it from re-entering the atmosphere. In contrast, California forests appear unable to cope with unmitigated global changes in the climate, switching from substantial C sinks to C sources by at least the mid-21st century. These results highlight the inherent risk of relying on forest C offsets in the absence of management interventions to avoid substantial fire-driven C emissions. On the other hand, since grassland environments, including tree-sparse rangelands, appear more capable of maintaining C sinks in 21st century, such ecosystems should be considered as an alternative C offset to climate-vulnerable forests. The further development of climate-smart approaches in California’s carbon marketplace could serve as an example to offset programs around the world, particularly those expanding into widespread arid and semi-arid regions.https://doi.org/10.1088/1748-9326/aacb39carbon cycleclimate changedroughtwildfiregrasslandforest |
| spellingShingle | Pawlok Dass Benjamin Z Houlton Yingping Wang David Warlind Grasslands may be more reliable carbon sinks than forests in California Environmental Research Letters carbon cycle climate change drought wildfire grassland forest |
| title | Grasslands may be more reliable carbon sinks than forests in California |
| title_full | Grasslands may be more reliable carbon sinks than forests in California |
| title_fullStr | Grasslands may be more reliable carbon sinks than forests in California |
| title_full_unstemmed | Grasslands may be more reliable carbon sinks than forests in California |
| title_short | Grasslands may be more reliable carbon sinks than forests in California |
| title_sort | grasslands may be more reliable carbon sinks than forests in california |
| topic | carbon cycle climate change drought wildfire grassland forest |
| url | https://doi.org/10.1088/1748-9326/aacb39 |
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