Clearly, Greg Asner would rather not talk about his 15 minutes of fame.<\/p>\n
\t\u201cIt\u2019s very embarrassing,\u201d he says of his having been named by Popular Science<\/i> magazine last October as one of its \u201cbrilliant 10\u201d scientists and researchers of 2007.<\/p>\n
\t\u201cIt just came out of the blue,\u201d Asner said in a recent interview, \u201cbut if it draws attention to the problems we\u2019re addressing, I guess that\u2019s okay.\u201d<\/p>\n
\tAnd these days, what\u2019s causing Asner to lose sleep are the many threats he sees to the survival of Hawai`i\u2019s native forests.<\/p>\n
\tAsner, a staff scientist with the Department of Global Ecology at the Carnegie Institution for Science, at Stanford University, and his team of about 10 scientists and technicians, conduct research around the globe. In mid-March, they flew to Kruger National Park in South Africa for several weeks as part of a multi-year study. In the past, the team has looked at ecological issues in the southwestern United States, the Amazon, and elsewhere.<\/p>\n
\tYet Hawai`i remains a special focus. After receiving a degree in aerospace engineering, Asner came to Hawai`i in the early 1990s. Here, he found work as a field technician with The Nature Conservancy, where he was introduced to the challenges of managing natural resources in the face of limited personnel and funds, on the one hand, and aggressive invaders, on the other.<\/p>\n
\tAfter his stint with TNC, Asner returned to school, receiving graduate degrees in ecology and biogeochemistry from the University of Colorado. For the last decade, he has been developing ways to streamline the process of gathering detailed information about natural resources on a large scale. The culmination of those efforts is the Carnegie Airborne Observatory, Asner\u2019s brainchild.<\/p>\n
\tThe observatory consists essentially of two instruments \u2013 one a Light Detection and Ranging (LiDAR) system that captures light reflected from up to 100,000 laser beams per second and which generates information on the physical characteristics of the landscape (forest canopy height, topography); the second is a high-powered spectrometer, analyzed by Robin Martin, Asner\u2019s wife and team member, which can measure the reflected light and generate information on the chemical properties of whatever the light hits. By comparing the known chemical profiles of plants with the chemical signatures read by the spectrometer, it\u2019s possible to identify what plants are in the forest below, and where they are \u2013 down to a single tree.<\/p>\n
\tAsner and his team mount the observatory in a small twin-engine plane, with a viewing hole cut into its floor. Flying at a height of up to 15,000 feet, for the last year, they\u2019ve been mapping Hawai`i\u2019s forests, focusing on the Big Island, but with a few excursions to Kaua`i thrown in for good measure.<\/p>\n
\tThe observatory is the evolutionary result of many years of tweaking technology that most often was developed with altogether different applications in mind. \u201cWe started with cameras, and then began using the hyperspectral imaging and LiDAR combination in 2007,\u201d Asner says. \u201cThe second-generation Carnegie Airborne Observatory is going to be in the works soon.\u201d<\/p>\n
\t\u201cThe whole process is based on increasing levels of technological mayhem,\u201d Asner says, describing the madness behind his methods. \u201cHardware is hard, but ecology is even harder. Driving everything is ecology.\u201d<\/p>\n
Sustainability<\/i><\/b><\/p>\n
\u201cWhat is the sustainability of Hawai`i\u2019s protected areas \u2013 against invasive species, land use changes, and climate change? How sustainable are these reserves?\u201d he continued. \u201cWhat is the efficacy of the work that is being done to protect them?\u201d<\/p>\n
\tUsing the airborne observatory, Asner and his team are able in hours to generate answers to questions that it would take months or years to resolve with traditional ground-based surveys. The observatory can map 20 acres per second, at a resolution of 1 meter. With Asner\u2019s maps, land managers can obtain near real-time information on what areas are vulnerable to invasion, where invasions are occurring, and where native forests are still intact.<\/p>\n
\tNot that airborne surveys will replace old-fashioned field work. \u201cWe still need field measurements,\u201d Asner says. \u201cEven now, we spend more time in the forest than above it.<\/p>\n
\t\u201cBut measuring some things on the ground is tough. Tree height, for example. That\u2019s hard to do on the ground, but from the air, it\u2019s a piece of cake.\u201d<\/p>\n
\tAlso, it\u2019s not yet possible to identify every species of weed from the air.<\/p>\n
\t\u201cThe signatures of some species can vary,\u201d Asner said. \u201cWaiwi\u201d \u2013 strawberry guava \u2013 \u201chas a constant signature and is easy to map.<\/p>\n
\t\u201cRubus, on the other hand\u201d \u2013 blackberry \u2013 \u201chas a variable signature, really variable. I think of it as sneaky. It can spread all over before it shows up in remote sensing. Morella faya is easy to spot, but Miconia is stealthy \u2013 until it gets to be a real problem.\u201d<\/p>\n
\tFor these reasons and more, Asner said, \u201cwe\u2019re careful not to oversell\u201d the potential of airborne observing. \u201cWe\u2019re still working on the science, in addition to management-related studies.\u201d<\/p>\n
\tIt\u2019s difficult work, with clouds playing havoc with scheduled surveys (the observatory needs clear skies). Conditions in the unpressurized aircraft require everyone aboard to wear oxygen masks. But Asner and the observatory are here for the long haul. The president of the Carnegie Institution has signed an agreement with the U.S. Forest Service, allowing the observatory to have office and lab space at the Hilo headquarters of the service\u2019s Institute of Pacific Islands Forestry.<\/p>\n
\tThe observatory is collaborating with the state to map additional forest reserve areas on the Big Island. Recently, Asner and his team began working with Forest Service and Army staff at Pohakuloa Training Area as part of a Department of Defense restoration ecology project. \u201cWe\u2019re trying to increase the extent and diversity of dry forest\u201d in the Pohakuloa and Pu`u Wa`awa`a areas of the Big Island, Asner says. \u201cWe decided we could figure out where to do restoration work with the airborne observatory \u2013 mapping the woody plants, the fire fuel, topography.\u201d<\/p>\n
\tAlthough Asner\u2019s work is still in its early stages, one thing has already become clear from his surveys: \u201cThe best forests we still see are surrounded by `a`a flows. As Rick Warshauer says, `a`a is the friend of the forest.\u201d<\/p>\n
— Patricia Tummons<\/p>\n
Volume 18, Number 10 April 2008<\/p>\n","protected":false},"excerpt":{"rendered":"
Clearly, Greg Asner would rather not talk about his 15 minutes of fame. “It’s very embarrassing,” he says of his having been named by Popular Science magazine last October as one of its “brilliant 10” scientists and researchers of 2007. … Continued<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[164],"tags":[],"class_list":["post-1230","post","type-post","status-publish","format-standard","hentry","category-april-2008"],"_links":{"self":[{"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=\/wp\/v2\/posts\/1230","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1230"}],"version-history":[{"count":0,"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=\/wp\/v2\/posts\/1230\/revisions"}],"wp:attachment":[{"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1230"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1230"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/environment-hawaii.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1230"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}