Researching the role of dissolved organic matter as a nutrient resource in freshwater ecosystems

研究溶解有机物作为淡水生态系统营养资源的作用

• 批准号: EP/Y033892/1
• 负责人: Penny Johnes
• 金额: $ 377.16万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY033892%2F1
• 关键词: Researching; role; dissolved; organic; matter

Freshwaters are losing biodiversity at a higher rate than any other planetary domain. A wide range of stressors are driving this trend, of which climate change and increasing nutrient delivery from food production and consumption are ubiquitous. Research to date on nutrient enrichment impacts on freshwater biota has been limited by the physical challenge of experimentation in a rapidly changing environment, and a narrow perception of bioavailable nutrient forms. It has focused on species-specific responses to inorganic nutrient forms, often in vitro or in lakes, rarely for flowing waters under ambient conditions, and usually for microbial or planktonic organisms, ignoring the responses of other biotic groups, community level responses to enrichment, and the combined impacts of the range of bioavailable organic compounds in freshwaters. Transformational research is needed to update current nutrient cycling theory for stream ecosystems, shifting from research explaining how part of the ecosystem responds to a limited range of stressors, to fundamental, holistic theory explaining how whole ecosystems respond to a broad palette of stressors. I will lead a multidisciplinary team to tackle this challenge, applying innovative techniques in molecular scale analysis, stable isotope probing and environmental genomics, under field and climatically-altered conditions. We will then use new data-driven modelling to understand relationships between taxonomic and functional shifts in response to dissolved organic matter (DOM) and inorganic nutrient exposure, revealing environment x gene interactions in biotic responses to nutrient and climate stressors. This will advance current theory and transform our understanding of the impacts of the full nutrient portfolio on freshwater ecosystems, revealing the specific role of DOM as this varies according to the composition of the DOM pool, species composition of the ecosystem, stream stoichoimetry and environmental character.

淡水生物多样性丧失的速度比任何其他行星领域都要快。多种压力因素正在推动这一趋势，其中气候变化以及粮食生产和消费带来的养分增加无处不在。迄今为止，关于营养富集对淡水生物群影响的研究受到快速变化环境中实验的物理挑战以及对生物可利用营养形式的狭隘认知的限制。它侧重于物种对无机营养形式的特定反应，通常是在体外或湖泊中，很少针对环境条件下的流动水体，通常针对微生物或浮游生物，忽略其他生物群体的反应，群落水平对富集的反应，以及淡水中生物可利用的有机化合物范围的综合影响。需要进行变革性研究来更新当前河流生态系统的养分循环理论，从解释生态系统的一部分如何响应有限范围的压力源的研究转变为解释整个生态系统如何响应广泛的压力源的基础、整体理论。我将领导一个多学科团队应对这一挑战，在现场和气候变化的条件下应用分子尺度分析、稳定同位素探测和环境基因组学方面的创新技术。然后，我们将使用新的数据驱动模型来了解响应溶解有机物（DOM）和无机养分暴露的分类和功能变化之间的关系，揭示生物对养分和气候压力源的反应中环境与基因的相互作用。这将推进当前的理论并改变我们对完整养分组合对淡水生态系统影响的理解，揭示 DOM 的具体作用，因为它根据 DOM 库的组成、生态系统的物种组成、河流化学计量和环境特征而变化。