Fire and herbivores as long-term drivers of grass-dominated systems in Central and Eastern Europe

中欧和东欧以草为主的生态系统（草原和森林草原）在生物多样性、气候、生计方面发挥着关键作用，并提供许多生态系统服务。就其生态而言，这些系统与森林有很大不同，面临着不同的威胁。它们往往不符合标准的生物多样性概念，如自然性和顶极植被的概念。人类的影响，加上对其起源和过去动态的有限了解，导致了以草为主的温带生态系统的退化和丧失。它们仍在积极推动重新造林，通过加强碳固定来减缓气候变化。需要具有广泛时间和空间尺度的方法来填补关于这些生态系统的知识空白。该项目将利用中欧和东欧（塞尔维亚和罗马尼亚）天然草原和森林草原的多代冰川和全新世记录，确定它们的起源和过去的动态，并确定维持它们及其生物多样性的因素。我将探讨两种消费者，火和食草动物对植被的作用，在气候条件随时间变化的背景下。我期待这些驱动因素之间的互动和反馈，以及人类影响相关的额外改变。在跨学科的方法中，我将结合一系列的古生态方法（木炭计量、花粉、植物大化石、粪芽孢、遗属变形虫和稳定同位素）和基于花粉的定量植被重建。利用考古和古生物数据库及种群动态信息，将有助于更全面地探索与草食类型、多样性和强度变化动态相关的植被组成和多样性变化。统计方法将有助于揭示系统状态中的临界阈值和转换。了解形成和维持以草为主导的系统及其非凡多样性的过程，将促进对它们的科学认识，并改善保护战略。这对于减轻未来气候、消费者和人类对该地区以草为主的生态系统的影响，保护自然资源、人类生计、生物多样性以及生态系统功能和服务至关重要。

Grass-dominated ecosystems (grasslands and forest-steppe) in central and eastern Europe play a critical role in biodiversity, climate, livelihoods, and offer many ecosystem services. In terms of their ecology, these systems differ significantly from forests and face different threats. They often do not conform to standard biodiversity concepts such as naturalness and the concept of climax vegetation. Human impact, combined with limited knowledge of their origins and past dynamics, has contributed to the degradation and loss of grass-dominated temperate ecosystems. Their reforestation is still actively promoted to mitigate climate change through enhanced carbon fixation. Approaches with broad temporal and spatial scales are needed to fill knowledge gaps about these ecosystems. This project will use multi-proxy Lateglacial and Holocene records from locations in natural steppe grasslands and forest-steppe in central and eastern Europe (Serbia and Romania) to determine their origin and past dynamics and identify the factors that maintain them and their biodiversity. I will explore the role of two consumers, fire, and herbivores on vegetation against the background of changing climate conditions over time. I expect interactions and feedbacks between these drivers, with additional alterations where human influence became relevant. In an interdisciplinary approach, I will combine a range of paleoecological methods (charcoal metrics, pollen, plant macrofossils, coprophilous spores, testate amoebae, and stable isotopes) and with quantitative pollen-based vegetation reconstruction. Using information from archaeozoological and paleontological databases and sources on population dynamics will help to explore more comprehensive changes in the vegetation composition and diversity associated with the dynamics of herbivory type, diversity, and intensity change. Statistical approaches will help reveal critical thresholds and transitions in system states. Understanding the processes that shape and maintain grass-dominated systems and their extraordinary diversity will advance their scientific recognition and improve conservation strategies. This is essential to mitigate future impacts from climate, consumers, and people on grass-dominated ecosystems in this region and conserve natural resources, human livelihoods, biodiversity, and ecosystem functions and services.