\n<\/p>\n
Victoria\u2019s mountain ash forests are thinning rapidly as the globe heats up, and could lose a quarter of their \u201cgiant\u201d trees that grow up to 80m tall in the coming decades, research has found.<\/p>\n
Forests of Eucalyptus regnans<\/em> \u2013 one of the tallest tree species in the world \u2013 lose about 9% of their trees for every degree of warming, according to a University of Melbourne-led study published in Nature Communications.<\/p>\n \u201cThese are giants,\u201d said lead author Dr Raphael Trouve. \u201cThey are the tallest flowering plant on Earth \u2013 that means they regularly reach 60 to 80m tall.\u201d<\/p>\n The researchers analysed data collected from mountain ash forests over more than 50 years to determine tree mortality rates and forest carrying capacity \u2013 the maximum number of trees of a given size that the forest can sustain.<\/p>\n They found that forests growing in the warmest conditions had the lowest carrying capacity, which further decreased with rising temperatures.<\/p>\n <\/span>Eucalyptus regnans lose about 9% of their trees for every degree of warming, research has found.<\/span> Photograph: University of Melbourne<\/p>\n \u201cWe found that for each extra degree of temperature, the number of trees that the forest can sustain drops by 9%,\u201d Trouve said. \u201cBy 2080 \u2013 with three extra degrees, as we expect \u2013 that tallies up to around a quarter of the trees gone.\u201d<\/p>\n The estimated forest loss did not include the additional impact of bushfires, which are expected to grow in severity as the planet warms up.<\/p>\n The forest thinning was thought to be the result of increased competition for limited resources. \u201cA growing tree needs space and resources to survive,\u201d Trouve said. \u201cUnder resource-limited conditions, such as water stress, a big tree will outcompete smaller, surrounding trees, causing their deaths.\u201d<\/p>\n Changes in forest carrying capacity would probably have knock-on effects. \u201cIts not just about trees, it\u2019s about the carbon they store, the planet we need, the water we drink,\u201d he said.<\/p>\n Mountain ash forests are considered one of the Earth\u2019s most carbon-dense ecosystems, storing more carbon per hectare than the Amazon. But as more trees died and decomposed, the forests would eventually shift from carbon sinks into sources of emissions, the study said.<\/p>\n skip past newsletter promotion<\/p>\n Sign up to Clear Air Australia<\/span><\/p>\n Adam Morton brings you incisive analysis about the politics and impact of the climate crisis<\/p>\n Privacy Notice: <\/strong>Newsletters may contain info about charities, online ads, and content funded by outside parties. For more information see our Privacy Policy. We use Google reCaptcha to protect our website and the Google Privacy Policy and Terms of Service apply.<\/span><\/p>\n after newsletter promotion<\/p>\n \u201cClimate change is stressing forests all over the world, and that can be exacerbating the rate of thinning\u201d said Dr David Bowman, a professor of fire science at the University of Tasmania with a background in eucalypt ecology, who was not involved in the study.<\/p>\n Bowman said climate change \u2013 and the combination of heatwaves, rising temperatures and chronic droughts \u2013 was placing forests under enormous stress globally, and particularly affected those in mid-latitude, temperate environments.<\/p>\n Giant trees were particularly vulnerable. \u201cThey\u2019re getting exhausted,\u201d he said.<\/p>\n Then, as forests were dying and thinning, they became more open and more flammable, as fuel \u2013 in the form of leaf matter, litter, fine branches and stems \u2013 accumulated in the forest.<\/p>\n The risk of bushfire then became a \u201cnightmare scenario\u201d for large trees \u2013 already struggling to survive \u2013 which would struggle to recover.<\/p>\n","protected":false},"excerpt":{"rendered":" Victoria\u2019s mountain ash forests are thinning rapidly as the globe heats up, and could lose a quarter of their \u201cgiant\u201d trees that grow up to 80m tall in the coming decades, research has found. Forests of Eucalyptus regnans \u2013 one of the tallest tree species in the world \u2013 lose about 9% of their trees<\/p>\n","protected":false},"author":1,"featured_media":17090,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[50],"tags":[10266,872,998,1870,1235,828,3116,313,2211,724,10265],"class_list":{"0":"post-17089","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-environment","8":"tag-ash","9":"tag-environment","10":"tag-forests","11":"tag-giant","12":"tag-lose","13":"tag-mountain","14":"tag-quarter","15":"tag-rise","16":"tag-temperatures","17":"tag-trees","18":"tag-victorias"},"_links":{"self":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/17089","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=17089"}],"version-history":[{"count":0,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/posts\/17089\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=\/wp\/v2\/media\/17090"}],"wp:attachment":[{"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=17089"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=17089"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/naijaglobalnews.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=17089"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}