Feedbacks between Biodiversity and Climate

陆地生态系统通过能量、水、元素和微量气体的循环，是气候的重要决定因素。虽然气候对生物多样性的影响已经得到了广泛的研究，但关于生物多样性对气候的影响以及这种反馈可以在多大程度上缓解或增加气候变化的程度，人们知之甚少。在这里，我们特别关注生物多样性对气候的反馈以及自然对人类的贡献。这将使我们能够更好地了解全球环境变化的连锁效应和反馈循环。解决这一问题的一个主要限制是气候或地球系统模型迄今使用的是一个非常简单的生物多样性参数化方案。这些方案只区分非常广泛的植被类别，如阔叶林和针叶林或植物功能类型。这种对功能多样性的简单分类不能很好地代表与处理生物多样性对大气的反馈有关的过程。在这个项目中，我们将使用两个动态植被模型DVM；Fate-HD和LPJ-Guess，结合两个气候模型：COSMO-CLM2和Chersa，以创建历史时期和两个排放情景(RCP2.6，RCP8.5)的生物多样性-气候耦合情景。通过计算比气候计算更精细的尺度来计算生物多样性和植被过程和影响，将克服植被类别有限的问题。我们应用了植被的精细尺度分类(EUNIS)，并另外对生物多样性和功能特性多样性进行了参数化。在这些模型中，生物多样性对气候的影响将通过1)整合植被数据库(SPLOT和欧洲植被档案，EVA)，结合来自Sentinel和Landsat的遥感数据以及来自COSMO-CLM2的缩小尺度的气候数据来参数化。来自这些植被数据库的信息也将被用来以前所未有的空间细节运行DVM(跨越阿尔卑斯山100米，穿越欧洲5公里)。将这些信息汇总到气候模型尺度(12千米)，将允许DVM通过将物理结构和生物地球化学性质传递给气候模型的校准过程将信息返回给COSMO-CLM2。然后，将通过排除特定的生物多样性相关变量或在模型中对它们进行随机化来调查生物多样性对气候的影响。这将使我们能够量化它们对整个欧洲过去和未来整个生态系统-气候系统的影响。此外，来自检测到的生物多样性-气候反馈的信息将直接与使用生态系统服务框架的自然对人类的贡献联系在一起。这将有助于更好地减轻气候变化的影响，并更好地向利益攸关方传达气候智能生物多样性和NCP管理的生物多样性-气候反馈。

Terrestrial ecosystems, through the cycling of energy, water, elements, and trace gases, are important determinants of climate. While impacts of climate on biodiversity has been extensively studied, little is known about the effects of biodiversity on climate and to what degree this feedback can mitigate or increase the degree to which climate is shifting. Here, we set a specific focus on the feedback of biodiversity to the climate and to nature’s contributions to people. This will allow for a better understanding of the cascading effects and feedback loops of global environmental change. A major limitation for solving this issue is the fact that climate or earth system models use a very simple parametrization scheme of biodiversity to date. These schemes only differentiate between very broad vegetation categories, such as broadleaved and needle leaved forest or plant functional types. Such a simple classification of the functional diversity is not capable of well representing the processes relevant to address biodiversity feedbacks to the atmosphere. In this project, we will use two dynamic vegetation models DVMs; FATE-HD and LPJ-Guess, in combination with two climate models: COSMO-CLM2 and CHELSA to create coupled biodiversity-climate scenarios for the historical period and for two emission scenarios (rcp2.6, rcp8.5). The problem of limited vegetation classes will be overcome by calculating biodiversity and vegetation processes and effects at a much finer scale than is calculated for climate. We apply a fine scale classification of vegetation (EUNIS) and additionally parameterize biodiversity and functional trait diversity. Biodiversity effects on the climate in these models will be parametrized by 1) integrating vegetation databases (sPlot and the European Vegetation Archive, EVA) in combination with remotely sensed data from Sentinel and Landsat and downscaled climate data from COSMO-CLM2. The information from these vegetation databases will also be used to run the DVMs at unprecedented spatial detail (100m across the Alps, 5km across Europe). Aggregating this information to the climate model scale (12 km) will then allow the DVMs to provide information back to the COSMO-CLM2 through a calibration process by which physico-structural and biogeochemical properties are passed to the climate model. The effect of biodiversity on climate will then be investigated by either excluding specific biodiversity relevant variables or randomizing them in the model. This will allow us to quantify their effect on the entire ecosystem–climate system across entire Europe for the past and the future. Furthermore, the information from the detected biodiversity–climate feedbacks will directly be linked to Nature’s contribution to people using an ecosystem services framework. By this will help to better mitigate climate change effects and to better communicate biodiversity–climate feedbacks for climate-smart biodiversity and NCP management to stakeholders.