Subalpine tree seedlings: Assessing aging methodology and drivers of establishment
Subalpine tree seedlings: Assessing aging methodology and drivers of establishment
复制标题
亚高山树苗：评估老化方法和建立驱动因素
DOI：
10.1016/j.foreco.2021.119516
复制
发表时间：
2021
影响因子：
3.7
通讯作者：
Donna Shorrock
中科院分区：
文献类型：
--
作者：
Zoe Schapira;Camille S. Stevens‐Rumann;Donna Shorrock
最近气候变化的影响威胁到全球范围内森林生态系统的健康和功能。广泛的树木死亡率改变干扰制度造成显着的不确定性，在亚高山生态系统的树木恢复。老化幼苗是了解树木再生的重要机制，当与长期气候配对时，可以提供亚高山树木建立的气候驱动因素的关键信息。在这项研究中，我们破坏性采样和年龄229云杉（Engelmann云杉）和冷杉（亚高山冷杉）幼苗甲虫影响和火灾后的亚高山林分在北方科罗拉多和怀俄明州南部。我们建立了非破坏性老化方法和苗木年龄之间的关系，以评估年龄代理预测苗木真实年龄的准确性。我们比较了高树苗建立和非建立年之间的气候条件，以确定亚高山树苗招聘的区域驱动因素。高度和顶芽疤痕计数是显着的苗龄预测，虽然相关性较弱，表现出抑制生长的老苗。生长季降水量与云冷杉林分建立呈显著正相关，而最低气温、年水汽压和气候水分亏缺与亚高山乔木林分建立呈显著负相关。高度和顶芽疤痕计数不准确预测准确的年龄亚高山树木建立甲虫影响的立场，但提供更准确的火后树建立。与长期气候相比，平均气候条件可能为亚高山林分的低水平树木建立提供合适的条件。然而，大型云冷杉建立脉冲发生在凉爽和潮湿的生长年相比，长期的平均水平，在一个变暖的世界新的幼苗招聘构成重大的不确定性。
The recent impacts of climate change have threatened the health and functioning of forested ecosystems on a global scale. Widespread tree mortality from altered disturbance regimes creates significant uncertainty about tree recovery in subalpine ecosystems. Aging seedlings is an important mechanism for understanding tree regeneration, and when paired with long-term climate, can provide critical information on climatic drivers of subalpine tree establishment. In this study, we destructively sampled and aged 229Picea engelmannii(Engelmann spruce) andAbies lasiocarpa(subalpine fir) seedlings from beetle-affected and postfire subalpine stands in northern Colorado and southern Wyoming. We modeled the relationship between nondestructive aging methods and seedling age to assess the accuracy of age proxies in predicting true age of seedlings. We compared climatic conditions between years with high tree seedling establishment and non-establishment years to ascertain regional drivers of subalpine tree seedling recruitment. Both height and terminal bud scar counts were significant predictors of seedling age, although correlations were weaker in older seedlings that exhibited suppressed growth. Growing season precipitation had a significant positive relationship with spruce-fir establishment while minimum temperatures, annual vapor pressure and climatic water deficits had significant negative correlations with subalpine tree establishment. Height and terminal bud scar counts do not accurately predict precise ages of subalpine tree establishment from beetle-affected stands but provide more accuracy in postfire tree establishment. Average climate conditions compared to long-term climate may provide suitable conditions for low-levels of tree establishment in subalpine stands. However, large spruce-fir establishment pulses occur in cooler and wetter growing years compared to the long-term average, posing significant uncertainty about new seedling recruitment in a warming world.
DOI：
10.1073/pnas.1815107116
发表时间：
2019-03-26
影响因子：
11.1
作者：
Davis, Kimberley T.;Dobrowski, Solomon Z.;Maneta, Marco P.
通讯作者：
Maneta, Marco P.
影响因子：
10.1
作者：
Coop, Jonathan D.;Parks, Sean A.;Rodman, Kyle C.
通讯作者：
Rodman, Kyle C.