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Sown field margins can improve the conservation of biodiversity in rural areas and can contribute to the aesthetics of rural landscapes, thereby potentially increasing public support for agri-environmental measures. However, these two functions do not necessarily coincide. This raises the question whether field margins that are appreciated for their contribution to landscape aesthetics also deliver on the conservation of biodiversity. We conducted choice experiments with different groups of citizens and collected biodiversity data in the Netherlands, to investigate if the number of colors and vegetation cover in field margins increased respondents' appreciation for them, and how these visual cues correlated with taxonomic diversity and abundance of plants and invertebrates in those field margins. Using manipulated photos, we also assessed whether the presence of colorful field margins in a range of different rural landscapes increased respondents' appreciation of those landscapes. Respondents preferred colorful margins with high vegetation cover and showed a preference for green rural landscapes with colorful field margins. The presence of colorful field margins increased landscape aesthetics most in the least appreciated landscapes. The number of colors correlated positively with the diversity of sown and spontaneous plant species, and overall invertebrate abundance and abundance of predatory invertebrates, but was not related to invertebrate diversity. Our results show for the first time that colorful field margins support both public appreciation and diversity of plants and abundance of ground-dwelling invertebrates, with potential advantages to farmers in terms of natural pest control, at least in intensively used agricultural landscapes. However, management practices to maintain a high number of colors over time may be detrimental for invertebrate diversity. To optimize the different functions, we recommend that field margin layouts should consist of a perennial part that is allowed to develop over time, in combination with a part that is managed for its colorfulness. [ABSTRACT FROM AUTHOR]

Ungulates have become abundant in many temperate forests, shifting tree species composition by browsing and altering soil physical conditions by trampling. Whether these effects cascade down to other trophic levels and ecosystem processes is poorly understood. Here, we assess the paths through which ungulates have cascading effects on other trophic levels (regeneration, litter, invertebrates, rodents and organic matter decomposition). We compared ungulate effects by comparing 15 response variables related to different trophic levels between paired fenced and unfenced plots in twelve temperate forest sites across the Netherlands, and used pathway analysis model to identify the (in)direct pathways through which ungulates have influenced these variables. We found that plots with ungulates (that is, unfenced) compared to plots without (that is, fenced) had lower litter depth, sapling diversity, sapling density, rodent activity, macro-invertebrate biomass, decomposition rate of tea bags, pine and birch litter and higher soil compaction. These findings were used in a path analysis to establish potential causal relationships, which showed that ungulate presence: decreased sapling density, which indirectly decreased rodent activity; decreased litter depth, which indirectly reduced invertebrate diversity; increased soil compaction, which also decreased invertebrate diversity. Soil pH decreased invertebrate biomass, which also increased nitrogen mineralization. Yet, we did not find cascading effects of ungulates on decomposition rates. Importantly, an increase in ungulate abundance strengthens the cascading effects in this system. Our results suggest that ungulates can trigger cascading effects on lower trophic levels, yet decomposition and mineralization rates are resilient to ungulate browsing and trampling. Therefore, temperate forests conservation could benefit by limiting ungulate abundance. [ABSTRACT FROM AUTHOR]

• We studied several key drivers of earthworm abundance and composition in wood logs. • Earthworms are also deadwood worms: their communities in logs are abundant and diverse. • Tree species, decay stage, forest and soil type affect earthworm communities in logs. • Deadwood resources contribute to earthworm diversity in forests. • Forest management leaving deadwood after logging contributes to earthworm diversity. Earthworms are ecosystem engineers associated with important soil functions. Despite the large amount of literature on earthworm ecology, relatively few studies have examined earthworms in deadwood or quantified their importance in this habitat. We investigated earthworm communities in decaying deadwood and disentangled how their community dynamics are influenced by variation in tree species, wood decomposition stage, and forest environment. Decaying logs (of standardised size) of ten common, temperate tree species were laid out to decay on the soil surface for four years. The experiment was carried out in the "tree cemetery" experiment LOGLIFE, in two contrasting temperate forests in the central Netherlands. The decaying logs yielded surprisingly rich earthworm populations, with on average 19 individuals per meter of log and in total belonging to 12 different species. Our findings highlighted that earthworm communities in deadwood in terms of composition and abundance were influenced by tree species, wood decomposition stage and forest type with different soil properties, as well as their interactions. After one and two years of decay, earthworm abundance was higher in the logs of Picea abies and relatively fast decomposing Populus spp. than in other trees, while this pattern changed after four years with higher earthworm abundance observed in the other tree species. Overall, Populus spp. supported the highest earthworm abundance, followed by Picea abies and Quercus robur. The earthworm community composition in the logs in the two forest sites had broadly similar dynamic trends of first becoming very dissimilar between one and two years, then relatively more similar from two to four years of decay, although the community composition differed between sites. The interacting influences of tree species, wood decay stage and forest environment on earthworm communities strongly suggest that diversity in deadwood resources contributes to earthworm diversity in forests. Thus, by mixing different tree species and logging gradually through the years, forest managers could enhance the diversity of this abundant and understudied component of deadwood invertebrate diversity. Further research should study the feedback loop between earthworm communities and decomposition of deadwood. [ABSTRACT FROM AUTHOR]