Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Universidad de Santiago de Chile (USACH), Facultad Tecnológica, Departamento de Gestión Agraria, Santiago, Chile.
Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Departamento de Ingeniería Geográfica, Facultad de Ingeniería, Universidad de Santiago de, Chile; Centro de Estudios en Ecología Espacial y Medio Ambiente, Ecogeografía, Santiago, Chile.
Sci Total Environ. 2022 Feb 1;806(Pt 2):150604. doi: 10.1016/j.scitotenv.2021.150604. Epub 2021 Sep 28.
Climate change-induced mortality of trees is a concerning phenomenon for global forest ecosystems. The rapid decay and death of long-lived trees can significantly impact forest dynamics, with effects that transmit through ecological networks, becoming more evident in organisms occupying high trophic levels, such as large and specialized woodpecker species. However, understanding how populations of high trophic level species respond to climate change is still a challenge. In this study it was analyzed 32-year data of social groups of the Magellanic Woodpecker (Campephilus magellanicus) in North Patagonia, a region facing increasingly frequent droughts and increased temperatures. A positive trend in the size of woodpecker social groups as a response to climate-induced tree senescence was tested. A causal structural equation model examining climate- tree senescence- woodpecker relationships was used. Increasing nonlinear trends and positive interannual growth rates (>10%) for tree senescence and group size were found. Lowland forest sites had higher levels of tree senescence and more numerous social groups. The causal model supported the positive effect of mean temperature on tree senescence and the positive association of woodpeckers with tree senescence. These results provide evidence of a climate-induced increase in tree senescence that causes an increase in the size of woodpecker social groups. It is suggested that accelerated decay and mortality of trees in the northern Patagonian forests will decrease the stocks of deadwood in the long term, threatening the persistence of this large woodpecker species.
气候变化导致的树木死亡是全球森林生态系统令人担忧的现象。长寿树木的迅速衰减和死亡会对森林动态产生重大影响，其影响通过生态网络传播，在占据高营养级的生物中更为明显，如大型和特化的啄木鸟物种。然而，了解高营养级物种的种群如何应对气候变化仍然是一个挑战。在这项研究中，分析了北巴塔哥尼亚地区 32 年的麦哲伦啄木鸟（Campephilus magellanicus）社会群体数据，该地区面临越来越频繁的干旱和气温升高。测试了啄木鸟社会群体大小作为对气候诱导的树木衰老的响应呈正趋势的情况。使用了一个因果结构方程模型来检验气候-树木衰老-啄木鸟之间的关系。发现树木衰老和群体大小的非线性趋势增加，年增长率（>10%）为正。低地森林的树木衰老水平较高，社会群体也较多。因果模型支持平均温度对树木衰老的正向影响，以及啄木鸟与树木衰老的正关联。这些结果提供了证据表明，气候变化导致树木衰老加速，从而导致啄木鸟社会群体的规模增加。有研究表明，巴塔哥尼亚北部森林中树木的加速衰减和死亡将长期减少枯木存量，威胁到这种大型啄木鸟物种的生存。
