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Sporobolus cryptandrus is a C4 perennial bunchgrass native to extensive areas of North America. As a non-native species, it has been reported from several continents, and it has been described as a transformer species in sand steppes of Central and Eastern Europe. However, its spreading ability across the landscape and within habitats has not been quantified, and factors determining its success have not yet been assessed. In this study, we focused on the largest stronghold of S. cryptandrus invasion in Hungary, where the species was first recorded in 2016, and investigated its present distribution in the landscape by mapping along dirt roads. In a separate local study in a heavily infested sand dune site of 2 km2, we assessed the infestation level and factors affecting the species' establishment. Our landscape-scale mapping found that in April 2023, the distribution of S. cryptandrus encompassed a largely contiguous 600 km2, with documented presence from 282 1-km2 mapping units. The species occurred more than 5 m away from roads in 71 mapping units, mostly in the centre of its distribution area. Sporobolus cryptandrus presence was negatively related to soil organic matter content and positively related to sand content. At the local scale, we found the species in 39% of vegetation plots in a sand dune site originally covered by Pannonic sand steppes, a priority habitat in the EU Habitats Directive. Sporobolus cryptandrus presence at this site was negatively related to the total cover of resident grassland but, surprisingly, was unrelated to the distance from roads. Collectively, these results suggest that primary spread occurs mostly along roads; these roadside populations likely serve as sources for establishment in neighbouring grasslands, but subsequent mass invasion becomes independent from roads. Together with the species' broad macroclimatic tolerance in North America and reported mass invasion events in Ukraine and Russia, our results suggest that S. cryptandrus likely poses a broad-scale threat to Eurasian dry grasslands, in particular on coarse-textured sandy soils with low vegetation cover. [ABSTRACT FROM AUTHOR]

High-resolution ecosystem maps increase the efficiency of policy implementation. However, due to challenges related to both data and methods, such maps of appropriate scale and quality are still rarely available for nationwide analyses. We present solutions to some typical challenges of national-scale ecosystem mapping through the new Ecosystem Map of Hungary. It is a comprehensive, spatially and thematically detailed map with a hierarchical typology. The mapping methodology combined several novel elements from the integration of various large-scale databases in a (theoretical) data cube to the use of image-based predictive mapping (with a Random Forest classifier, using Sentinel-1 and -2 and environmental data). A participatory method involving local experts was used for validation, addressing the lack of suitable reference data as well as improving map-maker and map-user interaction. Besides the original objective of supporting conservation-related decision-making, further uses emerged from a variety of fields including spatial planning, education and recreation. [ABSTRACT FROM AUTHOR]

Soil carbon/nitrogen (C/N) ratios can provide essential information on soil health such as nitrogen limitations for plants or soil microorganisms. Determining soil C/N ratios can be challenging for larger geographic units such as for catchments, as nitrogen heterogeneity depends on several factors like land use, soil types, vegetation cover or seasonality. This paper investigates C/N ratio changes at different levels for diverse land management and land uses at plot-, catchment-, and country scale. For the plot- and catchment scale the study also presents data on seasonal variabilities of C/N ratio. For the countrywide evaluation, a digital soil mapping method was applied. Substantial differences were noted in total nitrogen amounts for arable lands, where the 'no till' system had up to 54.7% higher TN compared with ploughing. Catchment based monitoring showed the highest fluctuations for TN in the case of forest soils, while C/N ratios were relatively stable over the course of different seasons for the diverse land uses. Comparison of the topsoil C to N ratios in the European LUCAS and national SIM datasets shows that the difference in expected values is considerable (consecutively 10.35 and 7.41). The discrepancy can be explained partly due to different thematic representativity for land use and partly because of differences in analytical methodology. In addition, samples were taken almost twenty years apart. Overall, our study highlights the significance of land use, land management systems, spatial heterogeneity, time of samples collections, and the inconsistencies between different sampling and measurement methods. [ABSTRACT FROM AUTHOR]