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Earthworms can act as ecosystem engineers by altering soil structure, which impacts other organisms and ecosystem functioning. Jumping worms (family Megascolecidae) originating in Asia have been spreading in North America, extending their northern range limits to Ontario, Canada in the last decade and to New Brunswick in 2021. At the northern limits of their current range, little research has been done to examine the effects of jumping worms in these new habitats since their recent establishment. Our objectives were to evaluate: (1) how jumping worms impact soil nitrogen and soil carbon; (2) how their presence impacts the abundance of non-native European earthworms (family Lumbricidae); and (3) whether two sampling methods (i.e., mustard solution and wooden discs) are equally effective at detecting jumping worms. We sampled a residential property in Oromocto, New Brunswick, which was the first location where jumping worms were found in the province. Jumping worms did not have significant impacts on the abundance and biomass of European earthworms or soil carbon content in the top 5 cm of the soil, but they did significantly affect soil nitrogen levels. Both sampling methods were equally effective at detecting the presence of jumping worms. Further research is needed in managed landscapes, urban areas, and forests to determine the ecosystem impacts and invasion dynamics of jumping worms in Canada as this invasion progresses. • Potential for non-linear effect of jumping worm abundance on soil nitrogen content. • No significant impact of jumping worms on European earthworm abundance or biomass. • No significant impact of jumping worms on total soil carbon content. • Mustard extraction and wood discs were equally effective at detecting jumping worms. [ABSTRACT FROM AUTHOR]

• Global meta-analysis on beetle diversity in tree plantations and reference forests. • Tree plantations harbour communities with lower diversity and altered composition. • Beetle abundance is lower in tropical tree plantations and for detrivorous species. • Plantations must be evaluated by composition instead on richness/abundance metrics. While mature forests are declining worldwide, tree plantations could provide habitats of conservation value for forest-adapted species. However, to what degree the fauna in tree plantations matches the diversity and composition of mature forest communities is still debated. In this meta-analysis, we used beetle species (Coleoptera) as biodiversity indicators to assess the conservation value (i.e. the log response ratio in species richness and abundance and the Soerensen similarity) of tree plantations versus reference old-growth forests. We tested the effects of biome, plantation age, tree species richness and origin, surrounding habitat and the trophic position of the focal guild on the diversity and composition of beetle communities. Our results showed that tree plantations generally harboured communities with 47% less individuals, 33% less species and a significantly distinct composition than old-growth forests. In the case that tree plantations had a similar number of species or individuals as old-growth forests, those plantations still displayed a 40% difference in species composition. Beetle abundance was significantly lower in tropical/subtropical plantations and for detrivorous species. We found no further significant drivers of beetle diversity and community composition in tree plantations. We conclude that, although tree plantations can provide crucial habitats for forest-adapted species, they generally harbour less diverse and significantly different communities, highlighting the conservation value of old-growth forests as biodiversity refuges. To properly assess the conservation value of plantations in different taxa, we propose the use of species composition instead of single diversity indices. [ABSTRACT FROM AUTHOR]

Earthworms are keystone organisms that influence both soil function and community assembly of other soil organisms. However, soils are increasingly threatened by global change, so there is an urgent need to consider earthworms in conservation strategies. Earthworm monitoring has been promoted in numerous European and country research programs, and the global interest in earthworm conservation is rising, resulting in a rapid increase in the availability of earthworm data. However, most research focuses on a limited number of local-scale indicators, mainly based on abundance, biomass, and species richness of assemblages along with Bouché's ecological categories. We argue that these metrics are insufficient to effectively address earthworm conservation issues. We suggest four ecological characteristics which may be more informative for the development of conservation plans. Measurement of how much a species is (i) rare or common, (ii) native/nonnative, endemic and invasive, (iii) a specialist or generalist, and (iv) a winner or loser in the Anthropocene are all promising tools to support earthworm diversity conservation. These metrics could also be applied to functional traits, but better definition of these traits is fundamental. Finally, we emphasize the need to broaden spatial scales in earthworm studies by analyzing alpha, beta and gamma components of diversity, as local diversity alone can be misleading. • Conservation ecology has been overlooked by earthworm researchers. • Commonly used earthworm assemblage metrics are insufficient for earthworm protection. • Research on rarity, nativeness, specialization, and temporal trend assessments must be encouraged. • Diversity components, emphasizing broader spatial scales, need greater consideration for earthworm conservation. [ABSTRACT FROM AUTHOR]