A recent study led by the US Geological Survey published in the journal Environmental Research Letters used ST-Sim to estimate the ecosystem carbon balance for the continental United States (CONUS) over the period from 1973 to 2010. The study used remotely sensed data to estimate the effects of land use and land cover change on ecosystem carbon balance. The study estimates that on average, ecosystems in CONUS have been a net carbon sink (254 TG Carbon per year) but that there is much inter annual variability. Forests are the largest carbon sink and the size of the sink due to forests has declined by 35% over the study period. The reasons for the decline in the size of the forest carbon sink are forest ageing and a reduction in the total area of forests in CONUS. The historic ecosystem carbon balance is more uncertain prior to 1985 when remotely sensed data sets of wildfire and other disturbances became available. In future, the model developed in this study could be used to evaluate the effects of alternative land use policies on future ecosystem carbon balance.
This journal article by Brian Miller and others, published in the journal Ecosphere, demonstrates how a scenario planning process can be combined with a state-and-transition simulation model of vegetation dynamics to inform land management decisions for rangelands in the face of climate change. The study highlights the benefits and challenges of engaging stakeholders in the development of simulation models to support decision making. The authors also identify some key tradeoffs between grazer density and vegetation composition, as well as between the short‐ and long‐term costs of invasive species management.
Course & Workshop
California Air Resources Board
U.S. Geological Survey
Apex Resource Management Solutions
This unique event begins with a two-day online course on the fundamentals of developing state-and-transition simulation models of landscape change, followed by an optional one-day workshop on how this approach has been used to integrate projections of land-use/land-cover change and terrestrial carbon dynamics across the state of California.
State-and-transition simulation modeling online course: June 12-13, 2018
This two-day course establishes the fundamentals attendees need to use the free ST-Sim software to develop spatially-explicit, integrated models of both landscape change and carbon dynamics. The course will be delivered interactively online with an option to follow the course in a group setting at the California Air Resources headquarters in Sacramento, California.
California land use and terrestrial carbon modeling workshop: June 14, 2018
This workshop focuses on how the U.S. Geological Survey has used the ST-Sim software to develop and apply the Land Use and Carbon Scenario Simulator (LUCAS) in California. The California Air Resources Board will host this workshop at their headquarters in Sacramento, California, with live-streaming available for those who are unable to attend in-person.
For additional details please visit: www.apexrms.com/training
In December 2017, Colin Daniel and others published a study in the journal Methods in Ecology and Evolution describing a new approach for integrating continuous stocks and flows into a state-and-transition simulation model (STSM). This is the method behind the Stock-Flow Add-On to the ST-Sim software, which allows users to extend their models developed in ST-Sim to include interactions between continuous state variables and STSMs. For example, a model in ST-Sim can now track forest carbon in any number of continuous carbon pools (i.e., live biomass, deadwood and soil), with fluxes between these carbon pools triggered by wildfire transitions in the STSM. The paper illustrates the approach by extending the original Hawaii STSM case study in Daniel et al. 2016 to integrated a spatially-explicit carbon budget model with a STSM of land use/land cover change.
Benjamin Sleeter and others at the U.S. Geological Survey and the State of California have recently completed a study published in Earths Future. This research demonstrates a new approach for projecting changes in Land Use and Land Cover Change (LULC) based on land use histories and demographic trends. This study suggests that estimates based on demographic trends alone will likely under represent the impacts of future LULC transitions when compared to a scenario representing business as usual projections. Simulations conducted as part of this study project that the greatest impacts of LULC change in California will occur in rangeland ecosystems.
SyncroSim Version 2, including the new rsyncrosim package for R, is now available for free download. This new version of SyncroSim represents a major milestone in the development of our scenario-based, stochastic modeling toolkit. With the release of Version 2, it is now possible to develop of any number of plug-in “modules” for SyncroSim – such as our flagship ST-Sim module for developing state-and-transition simulation models of landscape change – each representing one or more interconnected processes in a modeling project. Key new features of the SyncroSim software framework include: (1) the ability to connect multiple simulation models; (2) to script a modeling workflow from start to finish in programming languages such as R and Python; (3) to publish models for use by a non-technical audience using the new SyncroSim Lite user interface.
ApexRMS associate, Dr. Bronwyn Rayfield, recently coauthored a paper in Science on the effect of modularity on the ability of a network to withstand perturbations. This study is the first that experimentally demonstrates this theoretically predicted property of modular networks. The results have implications for network design across disciplines from ecology and conservation to financial systems.
A newly published article in Forest Ecology and Management by Colin Daniel and others demonstrates the use of ST-Sim as a tool to incorporate uncertainty into forest management planning. The approach is applied to two boreal forest landscapes in Ontario and quantifies the risk of shortfalls in future timber harvest due to uncertainties in wildfire. The article is available as a free download for a limited time. The ST-Sim model library used for this study is also available.
ApexRMS recently presented a webinar in collaboration with Dr. Matt Reeves and Dr. Paulette Ford at the U.S. Forest Service Rocky Mountain Research Station. The webinar demonstrates how a state-and-transition simulation modeling approach can be used to account for future uncertainties regarding climate change when evaluating alternative rangeland management strategies. This project focuses on the impacts of drought and grazing on rangeland productivity and composition. A recording of the webinar is available online.
A recent USGS led publication in the International Journal of Disaster Risk Reduction used ST-Sim to project land use change and associated population growth in tsunami hazard zones along the US Pacific Northwest coast. The study demonstrates how land change simulation modeling can be used by local governments to incorporate the hazard exposure implications of community growth in land use policy and risk reduction planning.