Work

Changes in nitrogen content and isotopic composition in subarctic Empetrum nigrum seeds in the period 1976–2010

Year: 2024

Type: article

Abstract: High latitude ecosystems are believed to be sensitive to increases in the availability of nitrogen (N) which may be the result of anthropogenic emissions or may be due to climate warming which accelerates the release of N from organic matter in the soil.These changes may be detected in the changes in N pools and their isotopic composition.We studied N content (N%) and isotopic composition (δ 15 N‰) along an elevational gradient in a subarctic environment in northern Finland, using Empetrum nigrum (crowberry) seeds collected annually over the past 35 years.We studied whether N% or δ 15 N‰ shows trends that can be attributed to anthropogenic nitrogen, and investigated the effect of climate variables on the N content of seeds.Among the years, variations in N% and δ 15 N‰, were mainly dependent on previous summer or growing season temperatures and were in opposite directions for N% and δ 15 N‰.Among the sites, N% and δ 15 N‰ were highest at a low elevation site, and lowest at the highest elevation site.Trends in δ 15 N‰ over time were contrasting among the sites: at the low elevation site trend was increasing, whereas at the highest elevation site the trend was decreasing.The trend in N% over time was increasing at the low elevation site.Our results suggest that N cycling in these systems has changed in the past 35 years, but there were differences among sites.

Source: Työväentutkimus Vuosikirja

DOI: 10.60910/44wp-ndmr

Authors: Hilasvuori, Emmi, Hari, Pertti, Aakala, Tuomas, Pulliainen, Erkki, Grace, John

Institutions: University of Helsinki, Finnish Environment Institute

Language: English

Topic: Isotope Analysis in Ecology

Subfield: Ecology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Climate action, Life on land

Open Access status: green

Funders: Helsingin Yliopisto, European Commission