ALCES

A Landscape Cumulative Effects Simulator. ALCES simulates past and future landscape change across large regions, and maps how ecological and cultural values respond to it. It is developed and delivered by Integral Ecology Group.

The primary contexts in which ALCES is applied

An animated map of an Alberta watershed from 1900 to the present, in which roads, well sites, cutblocks and settlement spread steadily across the landscape.
Reconstruction of change in cumulative development footprint over the past century in an Alberta watershed. Prepared using ALCES Flow.

Cumulative effects

The accumulation of risk from multiple development activities

Cumulative effects refer to changes in the environment caused by the accumulation of activities across space and time. Too often, decisions about future development focuses on individual projects and fails to identify the risk of gradual change caused by multiple development activities. The implication is that cumulative effects can lead to environmental and cultural degradation despite a rigorous, project-based impact assessment process. Much of Canada is impacted by development footprint — visit the free cumulative disturbance mapping tool to view how development footprint impacts watersheds across Canada.

Cumulative effects assessment is intended to address this shortcoming by evaluating the combined effects of activities as opposed to focusing on any single activity or project. To be effective, cumulative effects assessment needs to consider impacts across large regions and time frames. The full set of influential drivers of ecosystem change need to be addressed, which often includes multiple types of industrial development (e.g., forestry, agriculture, mining, energy), settlements, infrastructure (roads, transmission corridors), natural disturbances such as fire, and climate change. And assessment of outcomes needs to be comprehensive by evaluating impacts to a range of ecological and cultural values.

The platform

Mapping cumulative impacts with simulation modelling

Comprehensive cumulative effects assessment is challenging due to the need to track the combined impacts of multiple activities. Computer modelling is well suited to this task, providing a way to simulate and map change across large regions and long timeframes. ALCES is designed to facilitate cumulative effects assessment by making simulation of development and its impacts accessible without requiring a computer modelling background. To achieve this, ALCES tools are pre-populated with data and models so that users can efficiently map impacts to assess consequences of proposed developments and evaluate mitigation options.

At the core of ALCES is a powerful landscape simulator that models changes in land cover, footprint, and forest age across your region. This simulator drives calculations of a wide range of ecosystem indicators that are related to landscape composition such as intact landscapes, wildlife habitat, and opportunities for Indigenous land use—giving you a comprehensive picture of the ecological and cultural impacts of different scenarios.

See ALCES on your own region

20+ years
of cumulative effects assessments and land-use planning across Canada
2,000 – 500,000+ km²
the range of regions ALCES has been applied to
~30 m
the resolution the landscape is reconstructed at
matching most satellite-derived data products

How an assessment usually works

We build each assessment and tool around the questions an organization needs answered, so no two are alike. A common workflow compares a development scenario to a baseline.
Three screens from the ALCES web tools: selecting a study region on a satellite map, configuring a development scenario, and comparing a habitat indicator between a baseline and a scenario in the results viewer.

Establish a baseline

A baseline is a picture of your landscape at a moment in time, providing a point of comparison when interpreting impacts. A present-day baseline limits the ability to assess cumulative effects because impacts are assessed relative to an already disturbed present-day state. ALCES can generate precolonial or historical baselines that support cumulative effects assessment by mapping the impacts of past as well as potential future activities. In this example, a precolonial baseline is run for the Clearwater watershed in Alberta to map natural ecosystem condition.

Three screens from the ALCES web tools: selecting a study region on a satellite map, configuring a development scenario, and comparing a habitat indicator between a baseline and a scenario in the results viewer.

Add a scenario

ALCES is capable of running two types of forecast scenarios: project and long-term. Project scenarios add one or more proposed projects to the present-day landscape and recalculate the indicators to assess the cumulative effect of existing and future development. Long-term scenarios simulate uncertain future developments and fire using probabilistic rules, and are useful for land-use planning and strategic regional assessment. In this example, a project scenario is run to assess the cumulative impacts of a new project and existing developments in the Clearwater watershed.

Three screens from the ALCES web tools: selecting a study region on a satellite map, configuring a development scenario, and comparing a habitat indicator between a baseline and a scenario in the results viewer.

Compare

The impact of a development scenario can be assessed by comparing outcomes to a baseline. Greater departure from the baseline implies greater risk to the indicator. In this example, opportunity for Indigenous harvest of moose in the presence of the new project and existing developments is compared to precolonial opportunity for moose harvest.

Map historical change through time

ALCES can also map how impacts have accumulated through time. Mapping change over time provides a captivating approach for communicating issues such as infringement of Indigenous rights. The strategic perspective provided by historical analysis also illustrates the limited capacity of project-by-project impact assessment to address cumulative effects, thereby underlining the importance of managing development in an integrated manner.

Published work

Much of our work is confidential to the clients who commission it. These are selected papers and public reports, spanning two decades of assessments, that we are able to discuss publicly.
  1. Antwi, E. K., Rempel, R. S., Carlson, M., Darko, A. N., & Yohuno (Apronti), P. T. (2026). An assessment of mitigation strategies for maintaining a balanced moose-wolf-caribou system in Ontario’s ring of fire region. Frontiers in Forests and Global Change, 9.
  2. Carlson, M., Rempel, R., Goulet, W., & Bindle, L. (2026). Assessing Indirect and Cumulative Impacts to Indigenous Hunting. 45th Annual Conference of the International Association of Impact Assessment, Quebec City, Canada.
  3. Carlson, M., Straker, J., Berg, K., Bockstael, E., Borle, E., Bindle, L., Belisle, C., Bonnyman, M., Faichney, F., & Golden, D. (2025). Bringing Together Indigenous Knowledge and Simulation Modelling to Assess Cumulative Impacts to Indigenous Land Use in Northeastern Alberta, Canada. Environmental Management, 75(11), 2960–2976.
  4. Heim, N., MacDonald, R., Horsethief, C., Luke, C., Proctor, M., Machmer, M., Birdstone, V., Warden, R., Wullum, C., Plewes, R., Chernos, M., & Carlson, M. (2025). The Wolverine Project: Evaluating Cumulative Effects Within the Land of Ktunaxa Using the One Heart Method. Environmental Management, 75(11), 2931–2946.
  5. Lin, H.-Y., Ryan, M., Camfield, A., Carlson, M., Carrière, M.-A., Raymond, C., & Naujokaitis-Lewis, I. (2025). Using climate change metrics to inform conservation of Canada’s Priority Places for Species at Risk. FACETS, 10, 1–16.
  6. Antwi, E. K., Rempel, R. S., Carlson, M., Boakye-Danquah, J., Winder, R., Dabros, A., Owusu-Banahene, W., Berryman, E., & Eddy, I. (2023). A modelling approach to inform regional cumulative effects assessment in northern Ontario. Frontiers in Environmental Science, 11.
  7. Carlson, M. (2022). Grizzly Bear Movement and Conflict Risk in the Bow Valley: A Cumulative Effects Model. Yellowstone to Yukon Conservation Initiative.
  8. Carlson, M., Young, H., Linnard, A., & Ryan, M. (2022). Supplementing Environmental Assessments with Cumulative Effects Scenario Modeling for Grizzly Bear Connectivity in the Bow Valley, Alberta, Canada. Environmental Management, 70(6), 1066–1077.
  9. Rempel, R. S., Carlson, M., Rodgers, A. R., Shuter, J. L., Farrell, C. E., Cairns, D., Stelfox, B., Hunt, L. M., Mackereth, R. W., & Jackson, J. M. (2021). Modeling Cumulative Effects of Climate and Development on Moose, Wolf, and Caribou Populations. The Journal of Wildlife Management, 85(7), 1355–1376.
  10. Leston, L., Bayne, E., Dzus, E., Sólymos, P., Moore, T., Andison, D., Cheyne, D., & Carlson, M. (2020). Quantifying Long-Term Bird Population Responses to Simulated Harvest Plans and Cumulative Effects of Disturbance. Frontiers in Ecology and Evolution, 8.
  11. Carlson, M., Browne, D., & Callaghan, C. (2019). Application of land-use simulation to protected area selection for efficient avoidance of biodiversity loss in Canada’s western boreal region. Land Use Policy, 82, 821–831.
  12. Chetkiewicz, C.-L. B., Carlson, M., O’Connor, C. M., Edwards, B., Southee, F. M., & Sullivan, M. (2017). Assessing the Potential Cumulative Impacts of Land Use and Climate Change on Freshwater Fish in Northern Ontario. Wildlife Conservation Society Canada, Conservation Report 11.

See ALCES on your own region

Tell us where you work and what you need to assess, and we will set up a demonstration tool for your region and walk you through it.