Global Change Biology, Год журнала: 2025, Номер 31(1)

Опубликована: Янв. 1, 2025

The primary production of fjords across the Arctic and Subarctic is undergoing significant transformations due to climatically driven retreat glaciers ice sheets. However, implications these changes for upper trophic levels remain largely unknown. In this study, we employ both bulk compound-specific stable isotope analyses investigate how shifts at base fjord food webs impact carbon energy sources consumers. Focusing on two rapidly changing in Southern Greenland, used migratory char as an indicator species, sampling populations along environmental gradients within fjords, building upon assumption that feed primarily close their natal stream, thereby integrating a dietary gradient. Our analysis isotopes tissue confirmed premise, revealing consistent change resource use from outer inner fjord, which nonetheless served preferred feeding grounds. Essential amino acid further indicated nitrogen sources, with nutrient near glacier inputs characterized by low turbidity high iron levels. Notably, source were associated positions transfer polyunsaturated fatty acids, glacier-influenced lower level (size-corrected) accumulating higher high-quality docosahexaenoic (DHA). These findings highlight usefulness new analytical tools glacial can substantially alter web dynamics, enhancing flow nutritional quality fish ecosystems. Greenland studied could represent future other where retreating become land-terminating decrease. study underscores critical role dynamics affecting high-level consumers, such salmonids, globally.

Язык: Английский