Arctic Biodiversity Research Articles

Nematode and macrofaunal diversity in central Arctic Ocean benthos

Deep-sea diversity studies have revealed intriguing patterns on both local and regional scales, but there is insufficient evidence with which to evaluate these trends in the Arctic Ocean basin. We collected data on the diversity of benthic macrofauna and meiofaunal nematodes along two transects from the shelf margin to the North Pole. Contrary to prevailing paradigms, there was no change in diversity with depth between 1000 and 4273 m. There was a trend, however, toward reduced taxonomic richness for both macrofauna and nematodes with increasing latitude. Regional ( β-) diversity differences were not observed for nematodes, but significant contrasts in Bray–Curtis similarity-based community structure of macrofauna were seen between the Eurasian and Amerasian Basins, as well as between the Lomonosov and Mendeleev Ridges. Since fauna within the deep Arctic Ocean appear to represent a single species pool, we suggest that both local ( α-) and β-diversity may be determined by ecological processes in the Arctic, and are not the consequence of historical or evolutionary processes. Furthermore, insights gained from studies of benthic–pelagic coupling, known to play a significant role in determining benthic community structure and function at high latitudes, may also be useful in investigations of Arctic biodiversity. This model may be valuable in designing future studies of biodiversity, and for predicting potential impacts of climate change on diversity patterns.

'Arctic hotspot complexes' proposed priority sites for studying and monitoring effects of climatic change on arctic biodiversity

'Arctic hotspot complexes' proposed priority sites for studying and monitoring effects of climatic change on arctic biodiversity

Skirting around thin ice

Richard Harris drops in on an expedition charting Arctic biodiversity under increasing threat from climate change. Every now and then one crosses paths with someone who was clearly born in the wrong century — an avid knitter, a lutist, or someone who will actually sit down and write a letter. These anachronisms are harder to find in science, but they do exist. In fact, a small band of them revealed themselves during a research cruise this summer to the Arctic Ocean.

Glacial refugia, haplotype distributions, and clonal richness of the Daphnia pulex complex in arctic Canada.

As part of a large international Arctic biodiversity expedition (Tundra Northwest '99), we examined the distribution of members of the arctic Daphnia pulex complex (Cladocera, Anomopoda) from 121 tundra ponds, spread across 16 sites spanning a large portion of arctic Canada (i.e. from 62 degrees 22' N to 79 degrees 01' N; 66 degrees 45' W to 139 degrees 37' W). Using allozyme electrophoresis and mitochondrial (mt)DNA analyses, we examined the population genetic (clonal) structure of these populations. The following taxa were detected in this complex: Daphnia pulicaria, D. middendorffiana and D. tenebrosa. Clear geographical differences in mean clonal richness and diversity were observed, with most western sites exhibiting higher clonal richness and diversity, than sites in the eastern Canadian Arctic. For both the pulicaria group (i.e. D. pulicaria and D. middendorffiana) and D. tenebrosa, the highest mean regional clonal richness was detected from the southern section of Banks Island, an unglaciated site situated on the edge or directly in the eastern fringe of the Beringian glacial refuge. A significant negative correlation was found between geographical distance from the Beringian edge, and overall regional clonal richness (i.e. sites closer to the edge harboured greater clonal richness). These results clearly indicate that more recently deglaciated regions (i.e. eastern Canadian Arctic) harbour lower levels of clonal richness than western regions nearer Beringia. We discuss the role that glacial refugia have played in influencing both biotic and genetic diversity in arctic taxa.

Arctic and Alpine Biodiversity: Patterns, Causes and Ecosystem Consequences

Arctic and Alpine Biodiversity: Patterns, Causes and Ecosystem Consequences

Arctic and alpine biodiversity: patterns, causes and ecosystem consequences

Provided here is a synthesis of the patterns, causes and consequences of biodiversity in cold-dominated ecosystems. The first chapters document patterns and causes of genetic and species diversity of plants and animals emphasising the interaction between historical and contemporary factors in governing biodiversity. The second section addresses how biotic diversity has changed in the past, how it is currently changing, and how it will likely respond to future changes in climate and land use. The third section treats both the conceptual basis and the evidence that biodiversity influences the functioning of arctic and alpine ecosystems. Finally, the implications of terrestrial patterns of biodiversity for landscape patterns and patterns of diversity in aquatic ecosystems are covered.