{"id":63058,"date":"2021-06-24T08:51:54","date_gmt":"2021-06-24T15:51:54","guid":{"rendered":"https:\/\/in.nau.edu\/news\/?p=63058"},"modified":"2021-06-24T08:53:34","modified_gmt":"2021-06-24T15:53:34","slug":"boyd-aspen-drought","status":"publish","type":"post","link":"https:\/\/in.nau.edu\/news\/boyd-aspen-drought\/","title":{"rendered":"Drought affects aspen survival decades later, new NAU study finds"},"content":{"rendered":"

Drought\u2014even in a single year\u2014can leave aspen more vulnerable to insect infestation and other stressors decades later, a new study by NAU researchers found. Aspen trees that were not resilient to drought stayed smaller than others, growing more slowly and succumbing to an outbreak of insects known as aspen leaf miners that have plagued interior Alaska for more than two decades.<\/p>\n

The findings, led by research specialist Melissa Boyd<\/strong> and Regents\u2019 professor Michelle Mack<\/strong> of the Center for Ecosystem Science and Society and published in Ecosphere<\/em><\/a>, offer more clues to the scientific mystery of what causes trees to die and a possible preview of these forests\u2019 future as the climate warms. NAU assistant research professors Xanthe Walker<\/strong> and Logan Berner<\/strong>, Regents\u2019 professor Scott Goetz<\/strong> and postdoctoral researcher Adrianna Foster<\/strong> also contributed to the study.<\/p>\n

\u201cClimate warming in the boreal forest has brought with it more frequent drought and insect outbreaks,\u201d Boyd said. \u201cIt\u2019s important we understand how these increasingly common events might alter the fate of aspen in northern forests.\u201d<\/p>\n

Boyd and her team used tree rings, long-term ecological data and satellite imagery to reconstruct the story of eight sites in interior Alaska that experienced aspen mortality during the leaf miner outbreak between 1997-2013. They found that a 1957 drought hampered the growth of some trees. Decades later, those trees, light-starved in the sub-canopy, were predisposed to die during the insect outbreak.<\/p>\n

The researchers also found that the \u201cnormalized difference vegetation index,\u201d a satellite-based measurement of vegetation productivity, did a better job at capturing the growth of living trees than it did the insect-wrought fate of dying trees that were in the lower canopy. To accurately detect insect-driven growth declines and mortality of aspen and thus create a fuller picture of what\u2019s happening to these forests, the researchers suggest that we cannot solely rely on NDVI.<\/p>\n

\u201cAs the northern latitudes grow warmer, forests that were historically dominated by conifers are shifting to deciduous-dominated ones,\u201d said Mack, the study\u2019s senior author. \u201cAs they do, threats to these deciduous trees become a matter of global concern. It\u2019s imperative we learn more about how and why these trees die.\u201d<\/p>\n

Boyd enjoys working with aspen in part because their histories can be challenging to read, given their indistinct ring boundaries. She said her findings about what caused certain trees to die raises more questions about the trees that survive.<\/p>\n

\u201cCan the growth of surviving aspen recover after a leaf miner outbreak?\u201d Boyd asked. \u201cHow resilient are these trees, and how much damage can they sustain?\u201d<\/p>\n

Photo: Melissa Boyd studying aspens in Alaska. Credit: Samantha Miller, NAU<\/em><\/p>\n

\"Northern<\/a><\/p>\n

 <\/p>\n

Kate Petersen | Center for Ecosystem Science and Society<\/p>\n","protected":false},"excerpt":{"rendered":"

Drought\u2014even in a single year\u2014can leave aspen more vulnerable to insect infestation and other stressors decades later, a new study by NAU researchers found. Aspen trees that were not resilient to drought stayed smaller than others, growing more slowly and succumbing to an outbreak of insects known as aspen leaf miners that have plagued interior…<\/a><\/p>\n","protected":false},"author":59,"featured_media":63059,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11],"tags":[],"class_list":["post-63058","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-research-academics"],"acf":[],"_links":{"self":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/63058","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/users\/59"}],"replies":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/comments?post=63058"}],"version-history":[{"count":0,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/posts\/63058\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media\/63059"}],"wp:attachment":[{"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/media?parent=63058"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/categories?post=63058"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/in.nau.edu\/news\/wp-json\/wp\/v2\/tags?post=63058"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}