An alternate vegetation type proves resilient and persists for decades following forest conversion in the North American boreal biome
An alternate vegetation type proves resilient and persists for decades following forest conversion in the North American boreal biome
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在北美北方生物群落的森林转变之后，另一种植被类型被证明具有弹性并持续存在数十年
DOI：
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发表时间：
2020
影响因子：
5.5
通讯作者：
A. P. Williams
中科院分区：
文献类型：
--
作者：
Winslow D. Hansen;Ryan Fitzsimmons;J. Olnes;A. P. Williams
气候变化和自然干扰正在催化森林向不同植被类型的过渡，但这些新的群落是否是将持续数十年至数百年的有弹性的交替状态，目前尚不清楚。在这里，我们测试了不断变化的气候，干扰和生物相互作用如何塑造落叶阔叶林类型的长期命运，在美国阿拉斯加内陆严重野火后取代黑云杉。我们模拟了在不同气候情景下（当代，世纪中期，21世纪后期），火灾重现期（11-250年），距离种子源（50- 1000米）和浏览强度（背景，中度，慢性）的火灾后落叶林，在2004年严重火灾后取代黑云杉数十至数百年。我们确定了落叶林仍然是主要植被类型的条件组合，以及它返回黑云杉林，过渡到混合林（落叶物种和黑云杉共同占主导地位）或转化为非森林的组合。在86%的模拟中，落叶林持续存在，如果火灾重现期很短（≤50年），则最具弹性。当过渡到另一种植被类型发生时，混交林是最常见的，特别是当火返回间隔很长（>50年），最近的种子源是500米或更远。中度和慢性浏览也减少了落叶树苗的生长和生存，帮助黑云杉竞争，如果火返回间隔长，种子源是遥远的。当模拟被迫采用21世纪末的气候情景时，干燥的土壤偶尔会在短间隔火灾后转化为非森林，该情景预测变暖和增加的蒸汽压赤字。回到黑云杉林几乎从未发生过。合成.从黑云杉到落叶林的转变已经在阿拉斯加内陆的区域范围内进行，在整个北美北方生物群落中也广泛观察到了类似的转变。我们发现，这种北方落叶林类型可能是一个有弹性的交替状态，将持续到21世纪世纪，这是很重要的，因为未来的植被结果将塑造生物物理反馈区域气候和影响随后的干扰制度。
Climate change and natural disturbances are catalysing forest transitions to different vegetation types, but whether these new communities are resilient alternate states that will persist for decades to centuries is not known. Here, we test how changing climate, disturbance and biotic interactions shape the long‐term fate of a deciduous broadleaf forest type that replaces black spruce after severe wildfires in interior Alaska, USA. We simulated postfire deciduous forest that replaced black spruce after severe fires in 2004 for tens to hundreds of years under different climate scenarios (contemporary, mid 21st century, late 21st century), fire return intervals (11–250 years), distances to seed source (50–1,000 m) and browsing intensities (background, moderate, chronic). We identified combinations of conditions where deciduous forest remained the dominant vegetation type and combinations where it returned to black spruce forest, transitioned to mixed forest (where deciduous species and black spruce co‐dominate) or converted to nonforest. Deciduous forest persisted in 86% of simulations and was most resilient if fire return intervals were short (≤50 years). When transitions to another vegetation type occurred, mixed forest was most common, particularly when fire return intervals were long (>50 years) and the nearest seed source was 500 m or farther. Moderate and chronic browsing also reduced deciduous sapling growth and survival, helping black spruce compete if fire return intervals were long and seed source was distant. Dry soils occasionally caused conversion to nonforest following short‐interval fire when simulations were forced with a late 21st‐century climate scenario that projects warming and increased vapor pressure deficit. Return to black spruce forest almost never occurred. Synthesis. Conversion from black spruce to deciduous forest is already underway at regional scales in interior Alaska, and similar transitions have been widely observed throughout the North American boreal biome. We show that this boreal deciduous forest type is likely a resilient alternate state that will persist through the 21st century, which is important, because future vegetation outcomes will shape biophysical feedbacks to regional climate and influence subsequent disturbance regimes.
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影响因子：
3.1
作者：
Foster, Adrianna C.;Armstrong, Amanda H.;Ranson, K. Jon
通讯作者：
Ranson, K. Jon
影响因子：
3.7
作者：
Alexander, Heather D.;Mack, Michelle C.
通讯作者：
Mack, Michelle C.
DOI：
10.1016/j.envsoft.2018.03.021
发表时间：
2018-12
期刊：
Environ. Model. Softw.
影响因子：
--
作者：
J. Walsh;U. Bhatt;Jeremy S. Littell;M. Leonawicz;M. Lindgren;T. Kurkowski;P. Bieniek;R. Thoman;S. Gray;T. Scott Rupp
通讯作者：
J. Walsh;U. Bhatt;Jeremy S. Littell;M. Leonawicz;M. Lindgren;T. Kurkowski;P. Bieniek;R. Thoman;S. Gray;T. Scott Rupp
影响因子：
64.8
作者：
Walker, Xanthe J.;Baltzer, Jennifer L.;Mack, Michelle C.
通讯作者：
Mack, Michelle C.
过去四个世纪，阿拉斯加北方地区的森林演替和气候变化相互作用，控制了火灾活动
影响因子：
5.2
作者：
Hoecker, Tyler J.;Higuera, Philip E.
通讯作者：
Higuera, Philip E.