Koch Marcus A, Stock Clara, Kleinpeter Dorothea, Del Río Camilo, Osses Pablo, Merklinger Felix F, Quandt Dietmar, Siegmund Alexander
Centre for Organismal Studies Heidelberg University Heidelberg Germany.
Heidelberg Center for the Environment (HCE) Heidelberg University Heidelberg Germany.
Ecol Evol. 2020 Oct 28;10(23):13260-13274. doi: 10.1002/ece3.6924. eCollection 2020 Dec.
Ecosystem dry limits have been studied in the context of species biology, fitness, and interactions with biotic and abiotic parameters, but the interactive effects of these parameters remain underexplored. Therefore, information on the putative effects of global climate change on these ecosystems is often lacking.We analyzed the interplay between fine-scale landscape genetics and biotic and abiotic factors of terrestrial lomas in the hyperarid Atacama Desert, characterized by a fog-dependent vegetation type almost entirely dominated by one single vascular plant species.We showed that metapopulations of are genetically connected over many hundreds of square kilometers, and despite having a large potential for clonal propagation, genetic diversity is regionally and locally structured. At the landscape level, genetic diversity correlates well with fitness parameters such as growth, flowering, and vegetation density. We also observed fine-scale correlation with a 3-D landscape model indicating a positive feedback with seasonal fog occurrence and availability. The various interactions of biotic and abiotic factors resulted in regular linear banding patterns of vegetation arranged orthogonally toward the landscape slope. Ex situ growth experiments indicated that grows at optimal rates in this extreme hyperarid environment, and we can extrapolate mean biomass production for this ecosystem. . Our results suggest that the unique ecosystem of terrestrial lomas in the hyperarid Atacama Desert is an evolutionarily balanced and fine-scaled system. The vegetation itself is composed of long-lived and persistent modules. We developed a descriptive model of the various interacting factors, thereby also highlighting the severe threat caused by global climate change potentially associated with fog disturbance patterns along the Chilean Pacific coast.
生态系统干旱极限已在物种生物学、适应性以及与生物和非生物参数相互作用的背景下进行了研究，但这些参数的交互作用仍未得到充分探索。因此，关于全球气候变化对这些生态系统的假定影响的信息往往缺失。我们分析了超干旱阿塔卡马沙漠中陆地雾林的精细尺度景观遗传学与生物和非生物因素之间的相互作用，该地区以一种几乎完全由单一维管植物物种主导的依赖雾气的植被类型为特征。我们发现，该物种的集合种群在数百平方公里的范围内存在基因联系，并且尽管具有很大的克隆繁殖潜力，但遗传多样性在区域和局部层面上呈现出结构化。在景观层面，遗传多样性与生长、开花和植被密度等适应性参数密切相关。我们还观察到与三维景观模型的精细尺度相关性，表明与季节性雾气出现和可利用性存在正反馈。生物和非生物因素的各种相互作用导致植被呈现出与景观坡度正交排列的规则线性带状分布模式。异地生长实验表明，该物种在这种极端超干旱环境中以最佳速率生长，并且我们可以推断出该生态系统的平均生物量产量。我们的结果表明，超干旱阿塔卡马沙漠中陆地雾林的独特生态系统是一个进化上平衡且精细的系统。植被本身由长寿且持久的模块组成。我们开发了一个描述各种相互作用因素的模型，从而也突出了全球气候变化可能沿着智利太平洋海岸与雾气干扰模式相关联而带来的严重威胁。
