Extension of the soil monitoring network via tea bag initiatives: A 3000 km latitudinal gradient in European Russia

The increasing popularity and recognition of citizen science approaches to monitor soil health have promoted the idea to assess soil microbial decomposition based on a standard litter sample - tea bags. Although tea bag initiatives are expanding across the world, the global datasets remain biased in regard to investigating regions and biomes. This study aimed to expand the tea bag initiative to European Russia, which remains a "white spot" on the tea bag index map. We also added urban soils into the analysis, which were underestimated previously. We compared the standard and local tea brands to explore possible adaptations of the standard approach to regions with limited access to standard tea brands. The established monitoring network included natural and urban sites in six vegetation zones along a 3000 km latitudinal gradient. There was a very close linear relationship (R2 = 0.94-0.98) in the mass loss of alternative and standard tea litter. The mass loss of green tea in soil along the latitudinal gradient showed an increasing trend from north to south. Variations in the microbial decomposition of green tea were mainly explained by the latitudinal gradient, with low soil temperature identified as key factors hampering decomposition. Mass loss of the more recalcitrant rooibos tea was mainly determined via land use, with decomposition rates on average 1.3 times higher in urban soils. This pattern was in line with higher soil temperatures and pH in urban sites compared to natural counterparts. The findings of our study could prove valuable in extending the tea bag network of soil decomposition assessment into broader territories, including urban areas. Additionally, they could facilitate the involvement of citizen science and complete the database for C cycle modeling depending on climatic conditions.

Is ecology different when studied with citizen scientists? A bibliometric analysis

Ecology is broad and relies on several complementary approaches to study the mechanisms driving the distribution and abundance of organisms and their interactions. One of them is citizen science (CitSci), the co-production of scientific data and knowledge by nonprofessional scientists, in collaboration with, or under the direction of, professional scientists. CitSci has bloomed in the scientific literature over the last decade and its popularity continues to increase, but its qualitative contribution to the development of academic knowledge remains understudied. We used a bibliometric analysis to study whether the epistemic content of CitSci-based articles is different from traditional, non-CitSci ones within the field of ecology. We analyzed keywords and abstracts of articles published in ecology over the last decade, disentangling CitSci articles (those explicitly referring to citizen science) and non-CitSci articles. Keyword co-occurrence and thematic map analyses first revealed that CitSci and non-CitSci articles broadly focused on biodiversity, conservation, and climate change. However, CitSci articles did so in a more descriptive way than non-CitSci articles, which were more likely to address mechanisms. Conservation biology and its links with socio-ecosystems and ecosystem services was a central theme in the CitSci corpus, much less in the non-CitSci corpus. The situation was opposite for climate change and its consequences on species distribution and adaptation, which was a central theme in the non-CitSci corpus only. We only revealed subtle differences in the relative importance of particular themes and in the way these themes are tackled in CitSci and non-CitSci articles, thus indicating that citizen science is well integrated in the main, classical research themes of ecology.