By Teri Greene
The study, “Using ICESat-2 to Estimate and Map Forest Aboveground Biomass: A First Example” in the journal Remote Sensing, shows how NASA’s Ice, Cloud and land Elevation Satellite-2, or ICESat-2, can be used to estimate aboveground biomass, or AGB, of forests and map its distribution.
Narine said limited information on the three-dimensional structure of forests has contributed to uncertainties in determining carbon budgets. However, ICESat-2 can capture this information using a laser-based lidar (light detection and ranging) instrument.
Lidar facilitates direct three-dimensional structural measurements, and using this technology from a space-based platform translates to exciting possibilities for assessing forest resources up to global scales, Narine said.
Knowing the capabilities of ICESat-2 allows for a better understanding of the satellite’s capabilities and limitations for characterizing vegetation.
“With ICESat-2 providing elevation measurements globally, a plethora of indicators of ecosystem health and function — including a key surrogate measure of forest AGB — can be potentially estimated to support sustainable management of forests,” Narine said.
The ICESat-2 mission was primarily designed to capture ice measurements, but its capture of data over vegetated areas offers investigators broader insights into ecosystem structure and the potential to contribute to the sustainable management of forest ecosystems.
By Jenny Staltovich
The pet trade, plant nurseries and international shipping ports have long been blamed for spreading destructive invasive species in Florida.
But there’s another, less understood super spreader: hurricanes.
The powerful storms can transport species with high winds and flood water. They can also cause more enduring damage by wiping out native habitat, clearing the way for exotic species.
“They take hold and you have this alternative ecosystem and it’s hard to go back,” said Luke Flory, an ecologist at the University of Florida’s Institute of Food and Agricultural Sciences. “And then those invasive plants may have a different ecosystem function. They may not provide protection for the coastline for future hurricanes.”
But what if scientists could predict that spread, like a hurricane forecast track, once a storm hits?
That’s what Flory hopes could eventually come from a massive mapping project he and a team of researchers have undertaken.
“If we can identify invasions when they’re small,” he said, “we can manage them and remove them before they become large and more destructive.”
For their project, they’re looking at two of the state’s most destructive invasive plant species, Brazilian pepper and Old World climbing fern. State and federal wildlife managers spend about $45 million annually on invasive plants, with these two accounting for the lion’s share. By mapping them now, they can study how the plants respond to tropical storms and hurricanes and eventually provide forecasts.
By Eric Hamilton
Deforestation dropped by 18 percent in two years in African countries where organizations subscribed to receive warnings from a new service using satellites to detect decreases in forest cover in the tropics.
The carbon emissions avoided by reducing deforestation were worth between $149 million and $696 million, based on the ability of lower emissions to reduce the detrimental economic consequences of climate change.
Those findings come from new research into the effect of GLAD, the Global Land Analysis and Discovery system, available on the free and interactive interface Global Forest Watch. Launched in 2016, GLAD provides frequent, high-resolution alerts when it detects a drop in forest cover. Governments and others interested in halting deforestation can subscribe to the alerts on Global Forest Watch and then intervene to limit forest loss.
The Nature Conservancy has begun using a drone to aid its reforestation efforts in northeast Minnesota.
By Cody Nelson and Jiwon Choi
To understand the health of a forest, conservation workers typically hit the ground and survey the land acre by acre.
It can involve trudging through the woods with hiking boots or snowshoes, looking for gaps in the forest canopy that need restoring.
But this summer, the Nature Conservancy’s Minnesota branch found an easier way to survey the large swaths of forest that comprise some of the over 60,000 acres it manages in the state.
The conservancy began using a drone to aid its reforestation efforts in northeast Minnesota. It has helped in several ways from making highly detailed maps to providing flyover video in key areas.
“It’s almost like another staff member,” said Chris Dunham, the nonprofit’s forestry manager. “We’re a small, small forest team here and we can use every advantage we can get.”
While the forest may look quite thick from the bird’s-eye view, the vantage point can be misleading. The nonprofit has estimated hundreds of thousands of acres of North Shore forest is in need of some help.
One of the Nature Conservancy’s focuses in Minnesota is on restoring riparian gaps — or places along rivers and streams in the forest where trees have died or been cut down.
Restoring these gaps is good for preventing erosion into the river, sequestering more carbon in the forest and creating better wildlife habitat.
There’s still ground-truthing to do once the drone footage in hand, Dunham said, “but you can be way more efficient if you’ve already taken a cruise above the trees and know where you’re headed.”
By Soyeon Bae, et al
Recent progress in remote sensing provides much-needed, large-scale spatio-temporal information on habitat structures important for biodiversity conservation. Here we examine the potential of a newly launched satellite-borne radar system (Sentinel-1) to map the biodiversity of twelve taxa across five temperate forest regions in central Europe. We show that the sensitivity of radar to habitat structure is similar to that of airborne laser scanning (ALS), the current gold standard in the measurement of forest structure. Our models of different facets of biodiversity reveal that radar performs as well as ALS; median R² over twelve taxa by ALS and radar are 0.51 and 0.57 respectively for the first non-metric multidimensional scaling axes representing assemblage composition. We further demonstrate the promising predictive ability of radar-derived data with external validation based on the species composition of birds and saproxylic beetles. Establishing new area-wide biodiversity monitoring by remote sensing will require the coupling of radar data to stratified and standardized collected local species data.
Peter Krzystek, Professor for Photogrammetry and Remote Sensing at Munich University of Applied Sciences tells about new investigations into the 3D mapping of forests.
Modern remote sensing sensors offer completely new possibilities for an extensive and detailed 3D capture of tree populations, making it possible to map at very large-scale. In particular, LiDAR is today an established technique for fast and highly accurate 3D scanning from the aircraft, helicopter or drone where pulses of visible or near-infrared laser light at a particular wavelength are used to create 3D images. These 3D images are typically made up of a high density of data points, known as ‘point clouds’. The new full waveform technology, which reconstructs the complete path of the laser beam through the vegetation, makes it possible to map the forest structures in 3D more precisely. Moreover, digital aerial cameras enable a detailed reconstruction of the forest surface and provide – if fused with LiDAR data – extra spectral information in the infrared range for a characterisation of the tree species. All in all, these new technologies are ideally suited for the automatic and cost-effective collection and characterisation of forest stands.
Things are looking up in a swath of forest in southern Germany, thanks to innovative funding from the European Union for a project that aims to help policymakers better understand how the forest’s ecosystems work.
The ECOPOTENTIAL project uses satellite images for ecosystem modelling in 25 Protected Areas in Europe (as well as Kenya, the Caribbean and Israel) to address climate change and other threats to ecosystems. In the Bavarian forest, the images and mathematical models of ecosystems, or “Earth Observation tools”, are helping to assess the impact of climate change and pollution, and shape national protection policies.
UN Environment is one of many partners supporting the 2015-2019 ECOPOTENTIAL project, funded by the European Union to the tune of 16 million euros.
Within the ECOPOTENTIAL project, Earth Observation tools and “remote sensing”, including by aircraft and drones, are being used to better understand how vegetation is evolving across the park and over time.
Satellite and drone pictures are detecting patterns of dominant plant species, linking habitat characteristics with terrain, and tracking animal movements. The park administration is also carrying out intensive research on tree regeneration, the role of dead wood, and the impact of global warming and extreme climatic events on the future development of these ecosystems.
By John Sullivan, Office of Engineering Communications
Researchers using satellite imaging have found much greater than expected deforestation since 2000 in the highlands of Southeast Asia, a critically important world ecosystem.
Zhenzhong Zeng, a postdoctoral researcher at Princeton University and the lead author of a July 2 article describing the findings in Nature Geoscience, said the researchers used a combination of satellite data and computational algorithms to reach their conclusions. The report shows a loss of 29.3 million hectares of forest (roughly 113,000 square miles or about twice the size of New York state) between 2000 and 2014. Zeng said that represents 57 percent more loss than current estimations of deforestation made by the International Panel on Climate Change. He said most of the forest has been cleared for crops.
Because forests absorb atmospheric carbon, and burning forests contribute carbon to the atmosphere, loss of forests could be devastating. An accurate estimation of forest cover also is critical for assessments of climate change. Zeng also said transformation of mountainous regions from old forest to cropland can have widespread environmental impacts from soil retention to water quality in the region.
This article addresses professionals like foresters, ecologists, project developers, certifiers, and environmentalists (in the following called natural resources managers) who are new to the field of remote sensing or who want to update their basic knowledge.
What will you learn? You will learn to
distinguish between various data collection methodologies,
understand the pros and cons of different data sources, and
select the right data set to answer your questions efficiently.
By KATIERA WINFREY
Climate scientists credit a new satellite mapping system with helping firefighters battle wildfires, and they say the new system helps better connect fire agencies across the state.
A lot of the fire-spotting happens at the National Weather Service.
The fire-mapping system has proven to be most helpful in rural areas where wildfires popped up recently.