Invasive species often transform environmental conditions, exclude native species and alter ecosystem functioning, including key ecosystem processes underpinning nutrient and energy cycles. However, such impacts have been most documented during periods of invasive species dominance; their influences on functioning at lower relative abundances and after long-term establishment are less well-known.<p> <p>We ...

We review three long‐term research programs performed over the last four decades on the ecology and management of oligotrophic lake systems with different fish communities at 69&deg; N in Norway. Through whole‐lake perturbation experiments, intensive culling of stunted fish removed 35 tons (1984–1991) of Arctic charr <i>Salvelinus alpinus</i> in Takvatn (15 km²) and 153 tons (1981–1983, ...

The importance of long-term environmental monitoring and research for detecting and understanding changes in ecosystems and human impacts on natural systems is widely acknowledged. Over the last decades, a number of critical components for successful long-term monitoring have been identified. One basic component is quality assurance/quality control protocols to ensure consistency and comparability ...

1. Given the current rates of climate change, with associated shifts in herbivore population densities, understanding the role of different herbivores in ecosystem functioning is critical for predicting ecosystem responses. Here, we examined how migratory geese and resident, non-migratory reindeer—two dominating yet functionally contrasting herbivores—control vegetation and ecosystem processes in ...

Long-term patterns (1980-2008) in the structure of a macrobenthic sublittoral community on the rocky-bottom of a high Arctic fjord (Smeerenburgfjord) in northwest Svalbard were investigated using image analysis of underwater photographs from a permanently marked locality. Species composition revealed the locality to be characterized by calcareous algae, various brown- and red-algae, and several ...

Increased human activities in the Arctic pose a high risk for Arctic organisms to be chronically exposed to petroleum compounds. The endocrine disrupting properties of some of these compounds coupled with the metabolic costs of detoxification may have negative effects on the long and energy intensive reproductive development of polar cod, an Arctic keystone species. In the present study, selected ...

<p>1. Introduced or invading predators may have strong impacts on prey populations of the recipient community mediated by direct and indirect interactions. The long‐term progression of predation effects, covering the invasion and establishment phase of alien predators, however, has rarely been documented.</p> <p>2. This paper documents the impact of an invasive, specialized planktivorous fish ...

Climatic warming has been hypothesized to accelerate organic matter decomposition by soil microorganisms and thereby enhance carbon (C) release to the atmosphere. However, the long-term consequences of soil warming on belowground biota interactions are poorly understood. Here we investigate how geothermal warming by 6 °C for more than 50 years affects soil microbiota. Using metatranscriptomics we ...

Kelps are ecosystem engineers and thus enhance biodiversity and subsidize food webs in nearshore areas. Numerous studies describing diversity and abundance of biota associated with kelp have focused on sub-tropical and temperate waters while kelp forests at high latitudes, where kelp is predicted to expand in distribution, remain mostly unexplored. Kelp forests contribute significantly to regional ...