How can spatial analytics help Canadian forest industry meet increasing demand for wood products and yet, support sustainability of the wide range of values that our massive forests provide? Forsite shares its experience of more than 30 years of leveraging GIS for effective and sustainable forest management.
All physical landscapes are inherently dynamic in space and time, and forests––frequently impacted by natural disturbances and human activity––are no exception. While natural disturbances, such as forest fires, insects and disease outbreaks, are part of the normal life cycle of a forest ecosystem, human activities that involve harvesting and regeneration of forests are often planned to broadly emulate natural cycles.
With more than 347 million hectares of forest area, Canadian forests are a key part of our national identity and have played a significant role in our country’s history. In the 19th century, forest use in Canada went from small-scale wood-cutting that supported subsistence living to larger-scale, industrial harvesting and milling. These activities created employment for a significant portion of the workforce at the time and helped to develop roads and infrastructure in rural areas. As the volume of harvesting increased over time, governments began implementing policies to ensure a sustained yield of timber harvest into the future, and later refined these policies to include a wider range of values such as biological diversity and socioeconomic functions (also known as sustainable forest management).
Monitoring the spatial patterns of forest changes or disturbance processes is crucial for sustainable forest harvesting and development. Traditional forest databases, model outputs and field observations are now complemented by geospatial tools such as remote sensing and geographic information systems (GIS) to manage data and complete geospatial analysis. As a result, more current and accurate information is available to resource management professionals to aid in understanding landscape changes over a wide range of spatial scales and time intervals. One of the most powerful components of GIS is geoprocessing, which helps users define, manage and analyze the data to inform decisions. ArcGIS, combined with its many extensions, has over 200 geoprocessing tools.
In 1987, a small group of committed professionals focused on the operational delivery of forestry field services incorporated Forsite Consultants Ltd. in Salmon Arm, British Columbia. Today, with more than 130 employees in 11 cities across Canada, the company provides integrated forest land management services ranging from planning, resource analysis, timber development, silviculture and forest inventory to growth and yield support, and remote sensing or LiDAR services.
“Demand for wood products is increasing globally due in part to its smaller carbon footprint compared to traditional building products, but forests only have a finite ability to meet this demand. Forsite sits right in the middle of this equation. We work with governments, First Nations and the forest industry to help determine sustainable rates of harvest and where harvesting can occur over time,” says Cam Brown, resource analysis manager at Forsite. “We work to help our clients be successful at balancing the goals of sustainable timber production and maintenance of other values from forests such as water, wildlife habitat or recreation.”
Mapping Forest Disturbances
For over 10 years, Forsite has been working with Tolko Industries on watershed assessment projects in BC. Foresters planning to harvest in BC watersheds often need to understand the level of ‘disturbance’ in a watershed to help determine whether it is appropriate to pursue additional harvesting. Referred to as an Equivalent Clear-cut Area (ECA) assessment, the analysis helps measure how much of the watershed has been cut, burned or impacted by insect activity in the past and the level of hydrologic recovery associated with these past disturbances. The end product is a map of disturbances with their recovery level and a final ECA percentage for the watershed as a whole. If a watershed has an ECA greater than 30 per cent, a hydrologist will typically conduct field assessments to support decisions about additional harvesting.
To complete an ECA analysis, Forsite will define the watershed boundary and the condition of its land base in a forest cover inventory file. “The age or height of stands are grown to the current year using established growth curves and new harvest or burns are inserted into the file with associated attributes. Where available, LiDAR Canopy Height Model (CHM) data is used to assign updated heights to stands,” says Jessica Koroll, GIS specialist at Forsite. “We also include forest health impacts such as mortality from mountain pine beetle and buffer the current road lines to be counted as disturbances on the landbase.”
LiDAR Canopy Height Model (left) used to generate hydrologic impact (ECA) percentages for harvested areas (right)
Using geoprocessing tools in ArcGIS Desktop Analysis toolbox, the various inputs are combined to create a single dataset containing all required information to complete the analysis. Where LiDAR is available, Forsite uses the CHM raster and tools available through the ArcGIS Spatial Analyst extension to generate and update the forest cover inventory stand heights.
Based on these stand heights and/or mortality levels, a disturbance (ECA) percentage is assigned to each stand, and then the proportion of the disturbed area is calculated. To calculate the final ECA percentage for a particular watershed unit, the sum of all disturbance areas is divided by the gross watershed area. ArcPy––a Python site package to perform geographic data analysis, conversion, management and map automation–is used to script the process from start to finish whether it’s geoprocessing, attribute updates, addition or calculation of new fields, or even calculation of final stats.
At the end of the analysis, Forsite produces a map of the watershed illustrating areas of disturbance with the current level of hydrologic recovery, and tables providing areas by recovery level and the final per cent disturbance for the watershed as a whole.
“By helping forestry companies and hydrologists understand the current level of disturbance, we help support informed decision-making about the appropriateness of additional forest harvesting in the watershed,” concludes Brown.
Where’s the Wood?
For another project at Tolko Industries, Forsite was asked to assess thousands of possible harvest areas across vast landscapes and tenure types in Saskatchewan to determine potential volumes available for harvest (hardwood and softwood) and the cost of harvesting the wood in each of these locations. The process included understanding the optimal haul route and distance to milling facilities to estimate hauling costs.
Meadow Lake Oriented Strand Board Mill, Tolko’s only mill in Saskatchewan, has been operating since 2003 and primarily makes Oriented Strand Board (OSB) panels. They get their wood from a variety of sources including agricultural land, fringe forest lands and tenured areas such as the Prince Albert Forest Management Area (FMA).
“We began by identifying potential harvest locations and volumes in a radius of approximately 700 kilometres around the mill. Next, we added numerous attributes to each of the locations such as cost to access the location, logging, reforestation, stumpage and hauling costs in order to perform the final assessment. This process required numerous geoprocessing tools,” recalls Steve Smyrl, senior GIS analyst at Forsite. “For calculating optimum haul routes from each block to the mill site, we used ArcGIS Network Analyst.”
The Network Analyst toolset provides a variety of capabilities such as adding locations (nodes) to a network analysis layer, calculating the network location fields for a point feature class, generating direction information for a network analysis layer with routes and identifying the closest facility on the network. A unique aspect of the project was Forsite’s ability to create optimal haul routes, even when no clean road network was available (a raster cost surface was created from the non-cleaned road lines).
A log truck collects pine and spruce sawlogs from a log deck north of Prince Albert, Saskatchewan.
By creating a volume-cost layer, Forsite was able to present to its client a number of scenarios based on accessing different volumes from various locations in a way that lets the mill assess average and marginal costs as well as the risks of supply. This output allowed the mill to produce a fibre supply plan for future years with more accurate cost estimates. In addition, the client now had access to alternative supply plans and associated costs too.
In this age of precision forestry, it’s not just digital data capture using advanced technology but also operations intelligence and optimized decision-making that win Forsite new clients and industry recognition.
An Exclusive Esri User
Forsite began using GIS technology early on and has always focused on keeping pace with the technological advances in the industry. “We started off with Esri technology way back in the ‘80s,” Brown proudly shows an Esri Canada invoice from 1989. “Once we tried ArcGIS Desktop, there was no looking back. While we dabbled in some open-source GIS products for non-commercial purposes, we’ve always remained an exclusive Esri user.”
“If we’re able to create more cost-effective solutions, for example through scripting in ArcPy, which provide repeatability, error avoidance and transparency, we are happy. Ten years ago, it used to take weeks to create a map, but now, we can create 50 maps in less than an hour. The automation tools in ArcGIS Desktop have simplified the process phenomenally,” exclaims Koroll.
Forsite now often uses web maps to get clients to verify input datasets and review results rather than producing static maps. They admire the flexibility to adjust map content and scale during the review. In the future, they are looking at using dashboards to present analytical results to clients in a more flexible way – such as initially presenting only high-level results but still allowing clients to drill down into finer detail if they want to. Having used ArcGIS Desktop since the beginning, the team is now gradually moving to ArcGIS Pro and exploring ArcGIS Enterprise licensing.
“Original mapping products were confined to creating visual representations to communicate information. Now, clients ask tougher questions and have higher expectations. Fortunately, GIS provides us the capability to manage large spatial datasets and use them to answer more complex questions, as well as provide expert analysis to support better decision-making,” remarked Brown. “Forest management has become very sophisticated in the last few decades, and Forsite has succeeded in remaining on top of industry requirements.”
Canada is a global forestry leader and the use of cutting-edge spatial analytics technology is a sure way to continue reaping the benefits of its massive forests while also ensuring the sustainability of the wide range of values forests provide.
This article originally appeared in the Fall 2018 issue of ArcNorth News.