The stability of ecological communities is critical for the stable provisioning of ecosystem services, such as food and forage production, carbon sequestration, and soil fertility. Greater biodiversity is expected to enhance stability across years by decreasing synchrony among species, but the drivers of stability in nature remain poorly resolved. Our analysis of time series from 79 datasets across the world showed that stability was associated more strongly with the degree of synchrony among dominant species than with species richness. The relatively weak influence of species richness is consistent with theory predicting that the effect of richness on stability weakens when synchrony is higher than expected under random fluctuations, which was the case in most communities. Land management, nutrient addition, and climate change treatments had relatively weak and varying effects on stability, modifying how species richness, synchrony, and stability interact. Our results demonstrate the prevalence of biotic drivers on ecosystem stability, with the potential for environmental drivers to alter the intricate relationship among richness, synchrony, and stability.

Despite the growing interest in ecosystem services provided by intertidal wetlands, we lack sufficient understanding of the processes that determine the seaward extent of salt marsh vegetation on tidal flats. With the present study, we aim to establish a globally valid demarcation between tidal flats and salt marsh vegetation in relation to tidal range. By comparing results from a regional GIS study with a global literature search on the salt marsh-tidal flat border, we are able to define the global critical elevation, above which salt marsh plants can grow in the intertidal zone. Moreover, we calculate inundation characteristics from global tide gauge records to determine inundation duration and frequency at this predicted salt marsh-tidal flat border depending on tidal range. Our study shows that the height difference between the lowest elevation of salt marsh pioneer vegetation and mean high water increases logarithmically with tidal range when including macrotidal salt marshes. Hence, the potentially vegetated section of the tidal frame below mean high water does not proportionally increase with tidal range. The data analysis suggests that inundation frequency rather than duration defines the global lower elevational limit of vascular salt marsh plants on tidal flats. This is critical information to better estimate sea level rise and coastal change effects on lateral marsh development.

Ulceration of melanoma is associated with neutrophil infiltrates and lower survival rates opposite to non‐ulcerated melanoma. Neutrophils release neutrophil extracellular traps (NETs) that are chromatin structures loaded with antimicrobial proteins. Since NETs have been correlated with tumor progression, we investigated whether NETs appear in melanoma and affect melanoma cells. Indeed, human primary melanoma biopsies revealed neutrophils releasing NETs in all of 27 ulcerated melanomas, whereas NETs were absent in all of 7 non‐ulcerated melanomas. However, the quantity of intratumoral NETs did not correlate with tumor progression of melanoma. Interestingly, in vitro assays showed that melanoma cells attach to NETs via integrin‐mediated adhesion and that NETs inhibit tumor cell migration. Moreover, co‐culturing of NETs and melanoma cells had a cytotoxic effect on melanoma cells resulting in necrosis. Hence, we discovered in vitro an antineoplastic role of NETs in melanoma.

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To arctic breeding geese, the salt marshes of the International Wadden Sea are important spring staging areas. Many of these marshes have always been grazed with livestock (mainly cattle and sheep). To evaluate the influence of livestock grazing on composition and structure of salt-marsh communities and its consequences for habitat use by geese, a total of 17 pairs of grazed and ungrazed marshes were visited both in April and May 1999, and the accumulated grazing pressure by geese was estimated using dropping counts. Observed grazing pressure was related to management status and to relevant vegetation parameters.The intensity of livestock grazing influences the vegetation on the marsh. Salt marshes that are not grazed by livestock are characterised by stands with a taller canopy, a lower cover of grasses preferred by geese, and a higher cover of plants that are not preferred.Overall goose-dropping densities are significantly lower in ungrazed marshes compared to marshes grazed by livestock. Some ungrazed marshes had comparatively high goose grazing pressure, and these were all natural marshes on a sandy soil, or artificial mainland marshes with a recent history of intensive livestock grazing. Goose grazing is associated with a short canopy. The plant communities with short canopy, dominated by Agrostis stolonifera, Festuca rubra and Puccinellia maritima, together account for 85% of all goose droppings in our data.The sites that were not visited by geese differed very little from those that were visited, in the parameters we measured. This might indicate that there was no ARTICLE IN PRESS www.elsevier.de/jnc