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Project: Effects of land cover change on the carbon balance of terrestrial ecosystems in the U.S.

Year: 

Focus Areas: Landscape Change, Ecosystem Services (Carbon)

Project Overview:

(Paragraph 1 below - overview of LUCAS - explain what LUCAS is and how it relates to ST-Sim; then lead in to how it has been used in several different ways)

Terrestrial ecosystems play a significant role in the global carbon budget and may contribute towards mitigating future increases in atmospheric green house gasses (GHGs) (Sleeter et al., 2015). Changes in land use/land cover and climate impact the ability of terrestrial ecosystems to sequester carbon and associated GHG emissions to the atmosphere. Land management strategies in forests, grasslands, wetlands, and agricultural areas have the potential to increase the amount of carbon sequestered in terrestrial ecosystems. *Statement about large uncertainties associated with terrestrial ecosystem carbon forecasting under land-use and climate scenarios.* To address this uncertainty, our team at ApexRMS has worked with the United States Geological Survey (USGS) to develop the Land Use and Carbon Scenario Simulator (LUCAS) model. LUCAS combines a state-and-transition simulation model to predict change in land use/land cover classes, with a stock and flow model to simulate carbon dynamics within a scenario-based framework (Figure 1). The resulting product is a model which tracks changes in land use/land cover, land management, and disturbance, along with the impact of these processes on ecosystem carbon sequestration and carbon flux. By developing these two models within our ST-Sim modeling environment, users are given the flexibility to test a range of future scenarios of land-use and climate change and their impacts on carbon dynamics.

(Paragraph 2 below - National terrestrial carbon assessment (see AIMS and Environmental Reviews papers and some of the paragraphs))

Using the LUCAS model, we have collaborated with the USGS on a national terrestrial carbon assessment - the LandCarbon project. The objective of the LandCarbon project is to conduct regional-scale assessments, along with continued research and monitoring, of terrestrial carbon to enhance our understanding of carbon sequestration and GHG fluxes within the United States. LandCarbon assessments utilize data collected from land change studies, remote sensing, wildfire mapping, and hydrological and biogeochemical modeling in aquatic and wetland ecosystems to produce estimates of future potential carbon storage and GHG fluxes in the United States.

(Paragraph 3 below - National tidal wetlands carbon assessment (see AGU poster/abstract and lightning slide in PPT and CDI proposal))

Coastal wetlands play a significant role in carbon sequestration, thereby serving as valuable carbon sinks. These areas are highly vulnerable to changes in climate and land use. Current threats to coastal wetlands in the United States include increased rates of relative sea-level rise, storm surges, and urban and industrial development. Uncertainty regarding the effects of land use/land cover change on the capacity for carbon sequestration in costal wetlands and the implications of such loses to the national carbon budget are challenging for costal wetland management. To address these uncertainties and improve national-scale accounting of carbon stocks and GHG fluxes, we have collaborated with the USGS Wetland Carbon Working Group – established under the LandCarbon program – to adapt the Land Use and Carbon Scenario Simulator (LUCAS) to evaluate wetland GHG fluxes in a range of environments (e.g. the tidal portions of the Mississippi River Alluvial Plain). LUCAS’ primary model (the Landscape Simulation Model) incorporates disturbance scenarios such as hurricanes, flooding, and sea-level rise, along with transition probabilities calculated from historical coastal land cover data. This model feeds its projections into a secondary model (the Carbon Budget Model) which incorporates measurements of carbon pools and fluxes across the ecoregion, to produce a final projection of carbon sequestration for the ecoregion. Currently, we are working with the USGS to parameterize the LUCAS model for the conterminous U.S., to allow for both large-area assessments and local land management analyses at higher spatial resolutions (Figure 2).

(Paragraph 4 below - California carbon assessment: see GCB paper - pick a figure from this report?)

We have also been involved in a project assessing ecosystem carbon balance in California. Using the LUCAS model’s fully coupled state-and-transition simulation model along with regional estimates of carbon stocks and fluxes derived from a national assessment of ecosystem carbon balance (Sleeter et al., 2018), we produced projections of future ecosystem carbon and their associated uncertainties for the State of California under a wide range of land-use and climate scenarios. The LUCAS model was configured to estimate annual changes to California’s carbon stocks resulting from variables including vegetation productivity, litterfall, mortality, decomposition, leaching, emission, and harvest, with carbon stocks and fluxes responding to changes in land use and land cover derived from natural processes and anthropogenic activities across the study area (Figure 3). The influence of both short- and long-term climate variability on live biomass growth and dead organic matter (DOM) turnover were similarly incorporated into the model’s framework. This work demonstrates the utility of the LUCAS model in gauging the effectiveness of land-management practices aimed at mitigating terrestrial carbon emissions. Similarly, the LUCAS model can function as a tool for understanding future climate-biosphere feedbacks and ecosystem carbon balance within a landscape.

Additional Information:

YouTube video on California Carbon

USGS California Carbon Scenarios

Carbon Cycling in Tidal Wetlands in the Mississippi River Alluvial Plain - poster PDF

Sleeter, B.M., Liu, J., Daniel, C., Rayfield, B., Sherba, J., Hawbaker, T.J., Zhu, Z., Selmants, P.C., and Loveland, T.R. 2018. Effects of contemporary land-use and land cover change on the carbon balance of terrestrial ecosystems in the United StatesEnvironmental Research Letters. doi:10.1088/1748-9326/aab540

Sleeter, B.M., Marvin, D.C., Cameron, D.R., Selmants, P.C., Westerling, A.L., Kreitler, J., Daniel, C.J., Liu, J., and Wilson, T.S. 2019. Effects of 21st‐century climate, land use, and disturbances on ecosystem carbon balance in CaliforniaGlobal Change Biology. doi:10.1111/gcb.14677

 

 

USGS Land Carbon Figure 2
Figure 1. Pathway diagrams for the Hawai’i case study state-and transition simulation model with stocks and flows (STSM-SF). (a) Transition diagram showing state types (Agr = agriculture, Pla = plantation, Gra = grassland, Shr = shrubland, For = forest, Dev = developed, Bar = barren) and transitions (as arrows) for the land use/land cover change model. (b) Flow diagram showing stocks (as boxes) and flows (as arrows) for the terrestrial carbon budget model (Figure 2 from Daniel et al., 2018).
USGS Land Carbon Figure 6
Figure 2. Average annual carbon balance of the conterminous United States for forest, grassland, shrubland, and agricultural lands. Carbon stock in 1973 shown in bold, in Pg C. Carbon fluxes, in Tg C yr−1, shown with arrow sizes relative to NPP. Arrows pointing up indicate a transfer of carbon to the atmosphere (emission). Emissions associated with harvest (harv), fire, agriculture expansion (ag), and urbanization (dev) can originate from all carbon pools. Values in brackets indicate a loss of ecosystem carbon. Grain and straw emissions assume the agricultural product pools turn over on an annual basis. (Figure 6 from Sleeter et al., 2018)
Figure 3 (California carbon) 1
Figure 3 (California carbon) 2
Figure 3. Conceptual diagram of (a) state‐and‐transition simulation model and (b) carbon stock‐flow model used in this study. Green boxes denote ecosystem state classes and carbon pools included in the estimation of ecosystem carbon storage. Gray diamonds indicate land change transition processes and carbon fluxes considered in the model. Dynamic global vegetation model with subscripts indicates that flux was parameterized with a dynamic global vegetation model as a function of the subscripts indicated. 'LUC' indicates land‐use change. (Figure 2 from Sleeter et al., 2019).

Project:

Effects of land cover change on the carbon balance of terrestrial ecosystems in the U.S.

Client: U.S. Geological Survey

Year:

Focus Area: Landscape Change, Ecosystem Services (Carbon)

Tools: SyncroSim, ST-Sim, LUCAS

 

Project Overview:

(Paragraph 1 below - overview of LUCAS - explain what LUCAS is and how it relates to ST-Sim; then lead in to how it has been used in several different ways)

Terrestrial ecosystems play a significant role in the global carbon budget and may contribute towards mitigating future increases in atmospheric green house gasses (GHGs) (Sleeter et al., 2015). Changes in land use/land cover and climate impact the ability of terrestrial ecosystems to sequester carbon and associated GHG emissions to the atmosphere. Land management strategies in forests, grasslands, wetlands, and agricultural areas have the potential to increase the amount of carbon sequestered in terrestrial ecosystems. *Statement about large uncertainties associated with terrestrial ecosystem carbon forecasting under land-use and climate scenarios.* To address this uncertainty, our team at ApexRMS has worked with the United States Geological Survey (USGS) to develop the Land Use and Carbon Scenario Simulator (LUCAS) model. LUCAS combines a state-and-transition simulation model to predict change in land use/land cover classes, with a stock and flow model to simulate carbon dynamics within a scenario-based framework (Figure 1). The resulting product is a model which tracks changes in land use/land cover, land management, and disturbance, along with the impact of these processes on ecosystem carbon sequestration and carbon flux. By developing these two models within our ST-Sim modeling environment, users are given the flexibility to test a range of future scenarios of land-use and climate change and their impacts on carbon dynamics.

USGS Land Carbon Figure 2

Figure 1. Pathway diagrams for the Hawai’i case study state-and transition simulation model with stocks and flows (STSM-SF). (a) Transition diagram showing state types (Agr = agriculture, Pla = plantation, Gra = grassland, Shr = shrubland, For = forest, Dev = developed, Bar = barren) and transitions (as arrows) for the land use/land cover change model. (b) Flow diagram showing stocks (as boxes) and flows (as arrows) for the terrestrial carbon budget model (Figure 2 from Daniel et al., 2018).

(Paragraph 2 below - National terrestrial carbon assessment (see AIMS and Environmental Reviews papers and some of the paragraphs))

Using the LUCAS model, we have collaborated with the USGS on a national terrestrial carbon assessment - the LandCarbon project. The objective of the LandCarbon project is to conduct regional-scale assessments, along with continued research and monitoring, of terrestrial carbon to enhance our understanding of carbon sequestration and GHG fluxes within the United States. LandCarbon assessments utilize data collected from land change studies, remote sensing, wildfire mapping, and hydrological and biogeochemical modeling in aquatic and wetland ecosystems to produce estimates of future potential carbon storage and GHG fluxes in the United States.

(Paragraph 3 below - National tidal wetlands carbon assessment (see AGU poster/abstract and lightning slide in PPT and CDI proposal))

Coastal wetlands play a significant role in carbon sequestration, thereby serving as valuable carbon sinks. These areas are highly vulnerable to changes in climate and land use. Current threats to coastal wetlands in the United States include increased rates of relative sea-level rise, storm surges, and urban and industrial development. Uncertainty regarding the effects of land use/land cover change on the capacity for carbon sequestration in costal wetlands and the implications of such loses to the national carbon budget are challenging for costal wetland management. To address these uncertainties and improve national-scale accounting of carbon stocks and GHG fluxes, we have collaborated with the USGS Wetland Carbon Working Group – established under the LandCarbon program – to adapt the Land Use and Carbon Scenario Simulator (LUCAS) to evaluate wetland GHG fluxes in a range of environments (e.g. the tidal portions of the Mississippi River Alluvial Plain). LUCAS’ primary model (the Landscape Simulation Model) incorporates disturbance scenarios such as hurricanes, flooding, and sea-level rise, along with transition probabilities calculated from historical coastal land cover data. This model feeds its projections into a secondary model (the Carbon Budget Model) which incorporates measurements of carbon pools and fluxes across the ecoregion, to produce a final projection of carbon sequestration for the ecoregion. Currently, we are working with the USGS to parameterize the LUCAS model for the conterminous U.S., to allow for both large-area assessments and local land management analyses at higher spatial resolutions (Figure 2).

USGS Land Carbon Figure 6
Figure 2. Average annual carbon balance of the conterminous United States for forest, grassland, shrubland, and agricultural lands. Carbon stock in 1973 shown in bold, in Pg C. Carbon fluxes, in Tg C yr−1, shown with arrow sizes relative to NPP. Arrows pointing up indicate a transfer of carbon to the atmosphere (emission). Emissions associated with harvest (harv), fire, agriculture expansion (ag), and urbanization (dev) can originate from all carbon pools. Values in brackets indicate a loss of ecosystem carbon. Grain and straw emissions assume the agricultural product pools turn over on an annual basis.

(Paragraph 4 below - California carbon assessment: see GCB paper - pick a figure from this report?)

We have also been involved in a project assessing ecosystem carbon balance in California. Using the LUCAS model’s fully coupled state-and-transition simulation model along with regional estimates of carbon stocks and fluxes derived from a national assessment of ecosystem carbon balance (Sleeter et al., 2018), we produced projections of future ecosystem carbon and their associated uncertainties for the State of California under a wide range of land-use and climate scenarios. The LUCAS model was configured to estimate annual changes to California’s carbon stocks resulting from variables including vegetation productivity, litterfall, mortality, decomposition, leaching, emission, and harvest, with carbon stocks and fluxes responding to changes in land use and land cover derived from natural processes and anthropogenic activities across the study area (Figure 3). The influence of both short- and long-term climate variability on live biomass growth and dead organic matter (DOM) turnover were similarly incorporated into the model’s framework. This work demonstrates the utility of the LUCAS model in gauging the effectiveness of land-management practices aimed at mitigating terrestrial carbon emissions. Similarly, the LUCAS model can function as a tool for understanding future climate-biosphere feedbacks and ecosystem carbon balance within a landscape.

Figure 3 (California carbon) 1
Figure 3 (California carbon) 2
Figure 3. Conceptual diagram of (a) state‐and‐transition simulation model and (b) carbon stock‐flow model used in this study. Green boxes denote ecosystem state classes and carbon pools included in the estimation of ecosystem carbon storage. Gray diamonds indicate land change transition processes and carbon fluxes considered in the model. Dynamic global vegetation model with subscripts indicates that flux was parameterized with a dynamic global vegetation model as a function of the subscripts indicated. 'LUC' indicates land‐use change. (Figure 2 from Sleeter et al., 2019).

 

Additional Information:

YouTube video on California Carbon

USGS California Carbon Scenarios

Carbon Cycling in Tidal Wetlands in the Mississippi River Alluvial Plain - poster PDF

Sleeter, B.M., Liu, J., Daniel, C., Rayfield, B., Sherba, J., Hawbaker, T.J., Zhu, Z., Selmants, P.C., and Loveland, T.R. 2018. Effects of contemporary land-use and land cover change on the carbon balance of terrestrial ecosystems in the United StatesEnvironmental Research Letters. doi:10.1088/1748-9326/aab540

Sleeter, B.M., Marvin, D.C., Cameron, D.R., Selmants, P.C., Westerling, A.L., Kreitler, J., Daniel, C.J., Liu, J., and Wilson, T.S. 2019. Effects of 21st‐century climate, land use, and disturbances on ecosystem carbon balance in CaliforniaGlobal Change Biology. doi:10.1111/gcb.14677