Soil organic carbon (SOC) is a key indicator of healthy soils. Among the sources contributing to the SOC pool, the role of microbial biomass and especially necromass is often overlooked. Microbial necromass sometimes reaches 40 times of the microbial biomass, emphasizing the role of soil microorganisms in carbon sequestration. However, overall, determining necromass in soils is not common. In this study, we aimed to examine (i) the microbial biomass and necromass in agriculturally used soils across Austria, Central Europe, and (ii) the effect of environmental factors and soil parameters on biomass-necromass contributions in arable and grassland ecosystems.We sampled soils (soil corer with 2.5 cm diameter and 10 cm depth, 3 samples per site) from 400 sites across Austria, from 150 m a.s.l. up to 2500 m a.s.l. including croplands, grasslands, and grass strips. The cooled samples were analysed for microbial biomass using Chloroform Fumigation Extraction (CFE) and for microbial necromass using amino sugars extraction. Moreover, composite soil samples (2.5 cm diameter, 10 cm depth; 3 samples per site) were used to determine pH (CaCl2), SOC, texture, potassium, phosphorus, nitrogen, humus content. The climate data (mean annual air temperature and annual precipitation) was obtained from Geosphere Austria, the Austrian Federal Agency for Geology, Geophysics, Climatology and Meteorology, Vienna. Soil management data was obtained through questionnaires directly from the land owners or operators. Data were statistically analysed using CatBoost models.Average microbial carbon (MC) across sites was 401 ± 256 mg g-1 and microbial nitrogen (MN) 65.0 ± 48.9 mg g-1. Both MC and MN significantly increased in the order croplands < grass strips < grasslands (HSD, p

Pesticides pose risks to human health and the environment. Monitoring schemes often exclude small sites with fluctuating water levels, inhabited by many species, including amphibians. We sampled for pesticides and their metabolites in 68 amphibian spawning waters in Austria. We analyzed the number of pesticides and concentrations in relation to the surrounding land use. We tested for 165 pesticides and metabolites and found 54; 46% were herbicides. The median total pesticide concentration per site was 0.097 µg/L (range: 0–20.419 µg/L). Pesticides found were generally of lower toxicity. We calculated the pesticide toxicity for aquatic invertebrates, fish, birds, and mammals, as proxies for amphibians and the overall ecosystems. Arable land was associated with pesticide number, concentration and toxicity according to the Boruta model selection. However, due to highly variable concentrations (and therefore also variable toxicity) only pesticide number showed significances in a generalized linear model. In this model arable land was positively associated with the number of pesticides detected, while the proportion of grassland, scrubs, artificial surfaces and tree cover had negative effects according to the linear model. Our results highlight (i) a widespread contamination of small temporary water bodies, (ii) the presence of multiple pesticide residues (cocktails), commonly more harmful than single pesticides, at amphibian spawning waters. These results provide a basis for future studies investigating the effects of common pesticide combinations in controlled settings using realistic scenarios and enable better assessment of the potential risks to wildlife.

Earthworms play a vital role in soil agroecosystems, representing a major part of the total soil fauna. Through their activities they provide essential ecosystem services, including improving soil structure, increasing nutrient availability for plants and ultimately supporting plant growth and boosting crop production. In a nutshell, they make a major contribution to maintaining soil health. However, while earthworms are generally regarded positively in agricultural settings, they are also threatened, e.g. by intensifying land use, certain agricultural practices and climate change. A British study has already found that earthworm abundances have declined significantly in recent decades, suggesting that earthworms are indeed under pressure. In addition, different earthworm species play different roles in the soil and maintaining their diversity is key to promoting soil health. Here we present the results of a recent field study in which 400 sites in Austria were sampled for earthworms in order to investigate the total earthworm biodiversity in arable land, grassland and field margins. The goal was (i) to describe the current state of earthworm biodiversity on agricultural land in Austria, (ii) to determine the most important factors driving earthworm biodiversity, and (iii) to investigate the geographic distribution of earthworms in the country and whether this is linked with future threats and opportunities. Preliminary results suggest that about 30 different species inhabit these agriculturally used fields, representing around half of the known earthworm biodiversity in Austria. While earthworm communities differed little between land uses, higher intensity farming was associated with lower earthworm abundance and biodiversity. This is likely due to a combination of management factors and environmental conditions. Further research will provide a more detailed understanding of these effects and their interactions and allow us to take steps to promote earthworm biodiversity and thus soil health in the future.