Amazon-SOS: a Safe Operating Space for Amazonian Forests

该项目的总体目标是确定和通报人为干扰和气候变化对亚马逊雨林造成重大变化的风险。我们将解决我们这个时代的一个根本问题，即亚马逊雨林在21世纪死亡的可能性，并确定最容易受到影响的地区。我们将把这一新知识与主要利益相关者制定的政策和情景结合起来，共同为亚马逊设计一个安全运营空间。为了解决亚马逊死亡这一标志性问题，我们将在21世纪全球变暖的背景下，推进对森林如何在极端气候、森林火灾和森林砍伐的干扰及其相互作用后生长、衰退和恢复的新的生态学理解。我们将使用新的林地网络、无人机和卫星建立新的数据集，以生成气候对森林风险的近乎实时的地图，并跟踪整个流域的个体大树死亡情况。这些信息将一起用于数学模型，以帮助估计未来森林死亡的风险。我们将把这项工作与用于预测土地利用(森林转化、退化)对森林功能的影响以及这些森林为人类提供的生态系统服务的模型结合起来。这些成果将使我们能够向政策制定者提供有关未来土地利用选择的新信息，帮助他们建立最优的土地利用路径，将亚马逊地区大规模森林丧失或功能失调可能产生的风险降至最低。亚马逊森林在世界气候中发挥着至关重要的作用。此外，该地区每年通过植被生长吸收与人类相关的二氧化碳排放的5%-10%，在气候变化方面起到了巨大的刹车作用。极端气候(如干旱)、森林火灾和森林砍伐逆转了这一过程，导致对大气的净排放。如果这种情况在足够大的范围内发生，通过增加森林损失或增加气候变化率--或它们之间的相互作用--对全球二氧化碳和气候变化产生的积极影响，将使本已具有挑战性的巴黎气候目标几乎不可能实现。简而言之，气候变化、森林火灾和砍伐森林已被确定为亚马逊地区面临的主要加剧和相互作用的威胁。亚马逊森林的大量丧失，也被称为“亚马逊枯萎”，将对人类福祉、生物多样性、生物地球化学循环以及区域和全球气候产生巨大的负面影响。然而，全球气候变化与可能引发大规模死亡的人类干扰相结合的水平尚不清楚。随着人为砍伐森林和森林退化(如火灾、伐木)的增加，该地区的气候变化预计将变得更加剧烈。由于缺乏数据，以及模型目前不能很好地代表关键过程，人们对它们的影响知之甚少。我们汇集了英国和S在生态学、生态生理学、地球观测(使用卫星)和应用于亚马逊地区的植被生长、土地利用和气候的数学模型等领域的领先美国科学家。在理解气候压力和人类干扰对亚马逊地区的综合影响方面，我们处于独特的地位。我们的测量将建立关于完整和受干扰的森林、它们的稳定性以及驱动它们应激反应的生理学的新知识。这些知识的进步将使我们能够对森林-气候-土地利用相互作用进行新的建模，我们将利用这些模型向决策者提供信息。我们将与国家和国际层面的利益攸关方合作，共同开发土地使用情景，将未来气候和森林生态系统服务的风险降至最低。总体而言，我们建议在亚马逊森林的实证和模型研究方面取得多项重大和综合的进展，并将建立一个在地方、区域和全球产生重大影响的科学-政策对话。

The overall aim of this project is to determine and communicate the risk of significant change to the Amazon rainforest caused by anthropogenic disturbance and climate change. We will address a fundamental issue of our time, on the likelihood of Amazon rainforest dieback in the 21st century and identify regions that are most susceptible. We will combine this new knowledge with policies and scenarios developed by key stakeholders to co-design a Safe-Operating-Space for Amazonia. To address the iconic issue of Amazon dieback we will advance new ecological understanding of how forests grow, decline and recover following disturbance from climate extremes, forest fire and deforestation and their interaction in the context of 21st Century global warming. We will build novel datasets using a new forest plot network, drones and satellites to produce near-real-time maps of the risk to forests from climate, and track individual large-tree mortality across the basin. Together this information will be used in mathematical models to help estimate the risk of future forest dieback. We will join this work with models used to predict the effects of land use (forest conversion, degradation) on forest function, and the ecosystem services these forests provide to humanity. The outputs will enable us to deliver new information to policy makers regarding future options for land use, helping them to build optimal land use pathways that minimise the risks that may arise out of large-scale forest loss or dysfunction in Amazonia.The Amazon forest plays a vital role in the world's climate. In addition, by annually absorbing 5-10% of human-related CO2 emissions via vegetation growth, the region acts as a large brake on climate change. Climate extremes (eg drought), forest fires and deforestation reverse this process, causing net emissions to the atmosphere. If this were to happen on a large enough scale, via increased forest loss or increased rates of climate change - or their interaction - the resulting positive effect on global CO2 and climate change, would make the already-challenging Paris climate targets virtually impossible. In short, climate change, forest fires and deforestation have been identified as major intensifying and interacting threats to Amazonia. A substantive loss of Amazonian forest, also known as "Amazon dieback", would have huge negative consequences for human well-being, biodiversity, biogeochemical cycling, and regional and global climate. However, the level of global climate change combined with human disturbance that could trigger large-scale dieback is not known. Climate change is predicted to become more intense in the region alongside increases in human-driven deforestation and forest degradation (e.g fires, logging). Their impacts are poorly understood because of a lack of data, and because models cannot currently represent the key processes well enough. We have gathered leading UK and S American scientists in the fields of ecology, ecophysiology, Earth observation (using satellites) and the mathematical modelling of vegetation growth, land-use and climate as applied to Amazonia. We are uniquely positioned to make a step-change in understanding the combined effects of climate stress and human disturbance on Amazonia. Our measurements will build new knowledge about intact and disturbed forests, their stability and the physiology driving their stress responses. These knowledge advances will enable new modelling of forest-climate-land-use interactions which we will use to inform policymakers. We will engage with stakeholders from state to international levels to co-develop land-use scenarios that minimise risk in future climate and forest ecosystem services. Overall, we propose multiple large and integrated advances in empirical and modelling studies of the forests of Amazonia, and will build a science-policy dialogue that delivers significant impact locally, regionally and globally.