The Urban Forest Digital Twin

Ecological Society of America, Portland, Oregon August 7, 2023

Slides for Mike Hamilton's talk at the Ecological Society of America meeting, Portland Convention Center, August 7, 2023

Slide 1

I will be talking today about a "pandemic project" inspired by my new relationship with an Urban Forest, a long-time professional involvement with ecological monitoring technologies, and my participation in an NSF Rapid grant to build virtual field experiences for undergraduates.

After 35 years as a field station director for the University of California Natural Reserve System, I retired and moved to Oregon City and soon found a need to continue my science outreach as an advisor to the city planning department for natural resources, as well as an ecological mentor at our local community college nature center.

Slide 2

My research focus for a long time has been on incorporating a geospatial context to embedded sensing technologies for monitoring and modeling biodiversity and multi-scale ecological processes within the wildland-urban interface.

As I pivot to urban forest science, I realize the tools we developed for our large protected natural areas should work well for the human-dominated context of an urbanized forest ecosystem.

Slide 3

Individual trees, small parks, wetlands, and river greenways offer so much value for both people and the "urban biodiversity" that has adapted to the extensive modifications to their historic habitats. This is not to say that it's not a significant challenge for any native species to maintain a viable population, and it's clear that the populations of rare and more vulnerable species continue to decline.

In contrast, invasive species expand, and urban development intensifies.

The economic value of individual trees inside our city limits is far more than a comparable individual that would comprise a tract of managed forest on public or private lands outside the urban zone. This fact alone affords planning oversight and enhanced protection, which is much less likely to be the case in rural areas.

Unfortunately, people, climate, invasive species, and disease chip away at the relics of the expansive and utterly spectacular forests that once stood here.

Slide 4

The elephant in the room has become our uncertain climate or climate dysregulation.

Layered on top of the challenges imposed by a global pandemic, here in the Pacific Northwest, our forests (and us) experienced three extreme events that rapidly changed the forest structure and intensified an already stressful situation for nearly everyone in our state.

This trifecta of combustion, atmospheric dynamics, and thermal anomalies left people reeling and scientists scratching their heads about how to think about the future.

Slide 5

I’ve been pondering ways that I might focus on improving our understanding and appreciation of our local urban forest ecosystems. As a member of the Organization for Biological Field Stations, I was alerted to a unique opportunity to participate in a newly funded NSF Rapid project. The grant would pay for video equipment and staffing for training and development to create virtual teaching materials suitable for distance learning. More than 50 field stations volunteered to participate by providing materials and making videos about their station’s habitats, on-site research, ecological concepts, host live-streamed events. A subset group (including myself) would explore virtual reality and immersive video technologies. 23 field stations were provided a GoPro 360-degree immersive camera, and as a group we collaboratively designed a seasonal sampling protocol. I chose our local Environmental Learning Center to become an Urban Forest Digital Twin.

Slide 6

A digital twin is a virtual representation of a physical object, process, or system, such as the natural environment, that is constantly updated with real-time data and can be used to predict how changes may affect its physical counterpart.

Geographic Information Systems provide an underlying enabling technology, on top of which run models, visualizations, and IoT (Internet of Things) sockets for inputs from remote sensing imagery and environmental data.

Frameworks such as Buonocore et al. demonstrate how individual forest trees might be modeled and dynamically updated.

Slide 7

Last year, ESRI released an SDK (software development kit) for Unreal Engine 5, and this year added Unity, the two most prominent video game development platforms.

For the first time, database-driven geospatial attributes can inform the 3D rendering capabilities of the two video game engines.

A gamified interactive interface to entire cities is now possible with additional programming.

Slide 8

Similar tools have been engineered with forestry in mind.

Using GIS forest stand maps containing inventory data, a library of species-specific and age-class-specific, realistic tree models can be generated.

The stands can also incorporate understory communities, wildlife models, and built structures. Processes such as ambient environments (wind, sunlight) and wildfires are also supported.

Slide 9

I was anxious to try these tools and approaches at the nature center I had "adopted."

The John Inskeep Environmental Learning Center, located on the campus of Clackamas Community College in Oregon City, is a 2-hectare restored wetland and headwater source of Newell Creek, a tributary to the Willamette River.

Historically anadromous salmonids spawned as far as this reach; however, the fishery is no longer viable due to extensive urbanization and channelization.

The ELC is very popular with local birders and nature lovers and sees extensive use by K-12 public schools, the college, and active volunteers. Based at the ELC, the college offers unique place-based enrichment workshops for professional development in water resources, environmental management, and natural resources stewardship.

Slide 10

Our workflow incorporates a suite of technologies from still and video cameras, recreational camera drones, network cameras, weather stations, 3D rendering workstations, and a desktop server.

An extensive software library enables image rendering from stills and video in the field into multi-modal representations suitable for Web XR, a 3D standard for interactive delivery using phones, tablets, and VR goggles.

The engineering and computer science fields advancing 3D rendering are moving ever faster thanks to machine learning, and I admit the interactive experience built last year is now nearly obsolete!

Slide 11

The current data collection phase of the Virtual Field project ended last fall, and I recently completed demonstration portals which can be viewed on my website.

I won't guarantee that some of these portals won't "break" if you push them too hard, but in general, they give a glimpse of a future interactive digital twin with value for various uses and users.

Slide 12

The portals have been used for professional training of ecologists, land managers and environmental specialists.

K-12 students have had access to the portals to augment their field trips to the ELC, allowing for access to time-series views of the habitats, and to retrieve and contribute observations to iNaturalist.

BioBlitz events have brought parents and their kids out to explore nature, adding to the ELC citizen science database and gaining skills they can take home.

Slide 13

The Urban Forest Digital Twin project is only at its beginning. The next round of funding by NSF for the Virtual Field has been announced, although I haven't seen the proposed activities.

I will continue exploring efficient ways to convert street-level imagery into 3D tree models at a sufficient resolution to allow for time-series analysis of structural change. I'm also taking training on using Unreal Engine 5.2, which has some exciting improvements that are well-suited for this project.

Scaling up from there and fusing with top-down models could provide a rich city-wide immersive tool with nearly unlimited applications.

It will also make for an excellent video game.

I'll see you on the Holodeck!

Demo Portals