Sites In Central Europe Research Articles

Stabilization of the pine increment during recent years of low precipitation and high temperatures by removal of the spruce lower storey

In stands dominated by Scots pine in Central European nutrient-poor sandy forest sites, deterioration of pine health due to recent development in climate change has been observed, whereas the vitality of the Norway spruce growing in the lower storey of such stands has remained stable. The study aims to analyse the impact of the spruce lower storey on pine increments and performance in relation to drought stress. Wood core samples were collected using an increment borer from mature pines growing in deep, sandy soils with ground water at a depth that was unreachable by the roots in three plot pairs (blocks) consisting of a pine-spruce plot and a plot with the lower-storey spruce removed. The increments of earlywood and latewood were measured separately. Health status and soil moisture were also evaluated. Spruce removal increased the radial growth (tree ring width – TRW) of the pines, and this manifested earlier in the latewood. Spruce removal significantly changed relationship of TRW and umbrothermic index of released pines. The treatment also increased pine foliation, while increases of topsoil moisture in the transects were insignificant. The study indirectly proves the existence of inter-species competition in the rooting zone for water in soils where the ground water is unreachable by the roots. The flat root system of spruce creates a barrier that reduces the amount of water available for pines with deeper growing roots. To reduce the risk of the negative impact of unfavourable climate change on pine as the target species in commercial mature mixed pine forests with similar site and stand conditions, lower-storey spruce reduction can be recommended, even though this might locally and temporarily lessen the biodiversity of the forest stand.

A year-round observation of δ13C of dicarboxylic acids and related compounds in fine aerosols: Implications from Central European background site

Isotopic analysis of specific compounds in aerosols can be a useful tool when studying atmospheric processes. Here, we present the results of stable carbon isotope ratio (δ13C) measurements performed on a one-year set (n = 96, Sep. 2013–Aug. 2014) of dicarboxylic acids and related compounds in PM1 at a rural Central European background site, Košetice (Czech Republic).The most 13C enriched acid was oxalic (C2, annual average = −16.6 ± 5.0‰) followed by malonic (C3, avg. = −19.9 ± 6.6‰) and succinic (C4, avg. = −21.3 ± 4.6‰) acids. Thus, δ13C values decreased with an increase in carbon numbers. Azelaic acid (C9, avg. = −27.2 ± 3.6‰) was found to be the least 13C enriched.A comparison of δ13C of dicarboxylic acids from other background sites, especially in Asia, shows similar values to those from the European site. This comparison also showed that C2 is more 13C enriched at background sites than at urban ones. In general, we did not observe significant seasonal differences in δ13C values of dicarboxylic acids at the Central European station. We observed statistically significant differences (p value < 0.05) between winter and summer δ13C values solely for C4, glyoxylic acid (ωC2), glutaric acid (C5) and suberic acid (C8).The only significant correlations between δ13C of C2 and δ13C of C3 were found in spring and summer, suggesting that the oxidation of C3 to C2 is significant in these months with a strong contribution from biogenic aerosols. The strongest season-independent annual correlation was observed in δ13C values between C2 and C4, the two dominant dicarboxylic acids. Therefore, C4 appears to be the main intermediate precursor of C2 throughout the whole year.

Integrated approaches to understanding animal exploitation and dairying in the Central European Early Neolithic: a case study from Ludwinowo 7 (Kuyavia, Poland; c. 5250–5000 cal BC)

Recent genetic studies point towards 6th millennium BC central Europe as the core region for the emergence of the lactase persistence (LP) gene mutation -13,910*T, making it important to understand the intensity of milk production and consumption among Linearbandkeramik (or LBK) farming groups. However, it is not known if milking was part of the LBK Neolithic “package” from the start, or if it displayed a discontinuous pattern in time and space. Documenting the changing nature of prehistoric animal exploitation requires integrating multiple strands of evidence and here we detail multi-proxy research into animal management strategies and the intensification of dairying in Neolithic Europe, using the LBK site of Ludwinowo 7 in central Poland as a case study. Lipid biomarker and stable isotope compositions of food residues from vessels provide qualitative and quantitative assessments of the major animal products acquired and processed, while zooarchaeological analyses identify slaughter and butchery practices, revealing the nature of meat, milk and fat exploitation. Stable carbon and oxygen isotope analyses on cattle teeth are also undertaken to define seasonal herd management. This combined approach offers an integrated picture of animal exploitation and milk use at the central European LBK site of Ludwinowo.

Ambient ozone at a rural Central European site and its vertical concentration gradient close to the ground.

The representativeness of ambient air quality of an in situ measurement is key in the use and correct interpretation of the measured concentration values. Though the horizontal representativeness aspect is generally not neglected in air pollution studies, a detailed, high-resolution vertical distribution of ambient air pollutant concentrations is rarely addressed. The aim of this study is twofold: (i) to explore the vertical distribution of ground-level ozone (O3) concentrations measured at four heights above the ground-namely at 2, 8, 50, and 230m-and (ii) to examine in detail the vertical O3 concentration gradient in air columns between 2 and 8, 8 and 50, and 50 and 230m above the ground. We use the daily mean O3 concentrations measured continuously at the Košetice station, representing the rural Central European background ambient air quality observed during 2015-2021. We use the semiparametric GAM (generalised additive model) approach (with complexity or roughness-penalised splines implementation) to analyse the data with sufficient flexibility. Our models for both O3 concentrations and O3 gradients use (additive) decomposition into annual trend and seasonality (plus an overall intercept). The seasonal and year-to-year patterns of the modelled O3 concentrations look very similar at first glance. Nevertheless, a more detailed look through O3 gradients shows that they differ substantially with respect to their seasonal and long-term dynamics. The vertical O3 concentration gradient in 2-230m is not uniform but changes substantially with increasing height and shows by far the highest dynamics near the ground between 2 and 8m, differing in both the seasonal and annual aspects for all the air columns inspected. We speculate that non-linear changes of both seasonal and annual components of vertical O3 gradients are due to atmospheric-terrestrial interactions and to meteorological factors, which we will explore in a future study.

Calcium availability affects the intrinsic water-use efficiency of temperate forest trees

Intrinsic water-use efficiency (iWUE) of trees is an important component of the Earth’s coupled carbon and water cycles. The causes and consequences of long-term changes in iWUE are, however, still poorly understood due to the complex interplay between biotic and abiotic factors. Inspired by the role calcium (Ca) plays in plant transpiration, we explore possible linkages between tree ring-derived iWUE and Ca availability in five central European forest sites that were affected by acidic air pollution. We show that increasing iWUE was directly modulated by acid air pollution in conjunction with soil Ca concentration. Responses of iWUE to rising atmospheric CO2 concentrations accelerated across sites where Ca availability decreased due to soil acidity constraints, regardless of nitrogen and phosphorus availability. The observed association between soil acidity, Ca uptake, and transpiration suggests that Ca biogeochemistry has important, yet unrecognized, implications for the plant physiological upregulation of carbon and water cycles.

Cattle Make the Difference: Variations and Developments of Animal Husbandry in the Central European La Tène Culture.

The first part of our research focuses on the analysis of animal remains (>6000 identified specimens, NISP) from the Middle La Tène central settlement Haselbach in Lower Austria, one of the largest investigated archaeozoological assemblages of present-day Austria. Based on the age and sex profiles, the faunal assemblage from Haselbach shows characteristics of urbanization and centralization and bears striking similarities to the archaeozoological material of the central settlement of Roseldorf (Lower Austria), some 35 km northwest of Haselbach. The second part of our research discusses the historical and regional context of the archaeozoological results from Haselbach and compares them with other sites, based on a detailed review of published archaeozoological data from the La Tène period (c. 450 BC to the end of the first century BC). In total, 55 faunal assemblages from 46 sites in nine countries in Central Europe, representing different types of sites (lowland settlements, hilltop settlements, central settlements, oppida, assemblages of ritual activity, and mining sites) were examined. The synthesis of the archaeozoological data exhibits different husbandry strategies and suggests major changes, especially during the Middle La Tène period indicating agricultural intensification. The differences in the biological profiles of the major domesticated species are of crucial importance to better understand aspects of socio-economic organization; especially in the case of cattle, age and sex profiles are used to distinguish different patterns of cattle husbandry. Finally, morphometric and recent genetic analyses on cattle bones and teeth from La Tène sites in Central Europe provide new insights into the complex socio-economic behavior as well as long-distance networks, involving animal supply and mobility in an exciting period of change involving centralization and increasing influence from the South during the pre-Roman late Iron Age.

How weather triggers the emergence of bats from their subterranean hibernacula

Hibernation is one of the most important behaviours of bats of the temperate zone. During winter, when little food or liquid water is available, hibernation in torpor lowers metabolic costs. However, the timing of emergence from hibernation is crucial for the resumption of the reproductive process in spring. Here, we investigate the spring emergence of six bat species or pairs of bat species of the genera Myotis and Plecotus at five hibernation sites in Central Europe over 5 years. Using generalized additive Poisson models (GAPMs), we analyze the influence of weather conditions (air and soil temperature, atmospheric pressure, atmospheric pressure trend, rain, wind, and cloud cover) as predictors of bat activity and separate these extrinsic triggers from residual motivation to emerge from hibernation (extrinsic factors not studied; intrinsic motivation). Although bats in a subterranean hibernaculum are more or less cut off from the outside world, all species showed weather dependence, albeit to varying degrees, with air temperature outside the hibernaculum having a significant positive effect in all species. The residual, potentially intrinsic motivation of species to emerge from their hibernacula corresponds to their general ecological adaptation, such as trophic specialization and roosting preferences. It allows the definition of three functional groups (high, medium and low residual activity groups) according to the degree of weather dependence of spring activity. A better knowledge of the interplay of extrinsic triggers and residual motivation (e.g., internal zeitgebers) for spring emergence will help to understand the flexibility of a species to adapt to a changing world.

Long-term effects of clearcut and selective cut on seepage chemistry in a N-saturated spruce stand – Case study Höglwald

While comprehensive literature is available concerning the effects of clearcutting on N leaching via seepage water little information is available comparing different harvesting intensities. In order to close this gap of knowledge in 1999 an experiment comparing selective cut and clearcut at the Höglwald site was started. The Höglwald is a major Central European ecosystem study site and represents a typical spruce forest ecosystem in Southern Germany, subject to high nitrogen deposition. Bulk deposition, throughfall and seepage water concentrations at 0 and 40 cm depth were measured from 1999 until 2017 at three plots (control, clearcut, selective cut). Elemental fluxes were calculated using measured water fluxes (precipitation, throughfall) or calculated soil water fluxes using a hydrological model. Here we present the final results for the 17-year measurement period comparing different harvesting intensities from initial harvesting until the complete removal of all mature trees.Initial nitrate peaks after clearcutting the nitrogen saturated spruce ecosystems were very high (up to 34 mg nitrate-N l−1) but short-lived (2 years). Afterwards nitrate leaching strongly decreased to values close to zero due to reduced input and the demand of the upcoming vegetation. For the investigated 17-year period cumulative nitrogen losses at the clearcut plot were lower as compared to the uncut control. The selective cut was not able to prevent nitrate leaching in our N-saturated spruce stand. Here cumulative nitrogen losses in the first 17 years are similar compared to the uncut control due to a combination of ongoing high deposition and partially enhanced mineralisation after harvesting events.At our nitrogen saturated study site the selective cut showed no advantages concerning nitrate leaching via seepage water. From a silvicultural and forest ecological point of view, however, big cleared areas with their sudden change to a non-forest climate should be avoided due to several disadvantages like high initial mineralisation with its excessive nutrient release, the risk of grass invasion as well as higher stress and often lower quality of the planted trees.

Anthropogenic and biogenic tracers in fine aerosol based on seasonal distributions of dicarboxylic acids, sugars and related compounds at a rural background site in Central Europe

Water-soluble organic compounds in aerosols are considered as relevant indicators of atmospheric processes. Fine particulate matter (PM1) samples were collected at National Atmospheric Observatory Košetice (NAOK), a rural background site representative of Central Europe, from September 27, 2013 to August 9, 2014. The samples (n = 146) were analyzed for water-soluble dicarboxylic acids (hereafter referred to as diacids) and related compounds to identify their seasonal variations and origins. Based on the Positive Matrix Factorization (PMF) analysis, we identified 5 factors – 2 anthropogenic, 2 biogenic and 1 background factors.In winter, anthropogenic contributions dominated in total organic matter (OM). Typical tracers for the main winter anthropogenic factor 1, connected with biomass burning (BB), were anhydrosugars together with maleic (M), methylmaleic (mM) and methylsuccinic (iC5) acids. This BB factor accounted for 64.1 ± 14.3% of OM in winter (annual avg. 36.7 ± 27.4%). A secondary anthropogenic factor 2 was characterized by phthalic (Ph), terephthalic (tPh) and ketomalonic (kC3) acids, which we assigned to secondary combustion products. The contribution of anthropogenic factor 2 was at a similar level throughout the year (12.5 ± 10.1% in OM). Mainly in winter, although also in spring and autumn, was the characteristic formation of diacids by secondary aqueous phase reactions, typically accompanied by lower temperatures, global radiation and ozone (O3) concentrations, yet higher relative humidity (RH) and aerosol liquid water content (ALWC).In summer, contributions of biogenic origin dominated. Secondary organic aerosols (SOA) of biogenic origin were typically represented by malonic (C3), methylmalonic (iC4), 3-oxopropanoic (ωC3), 4-ketopimelic (kC7), 7-oxoheptanoic (ωC7), pimelic (C7) and suberic (C8) acids. The factor, named as Biogenic 1, was dominant in summer with a contribution of 40.3 ± 19.6% in OM, while in other seasons, its contribution was below 10%. This factor was mainly characterized by a relative summer increase in the concentrations of kC7 and ωC7 acids. The second biogenic factor 2, also significant in summer (36.8 ± 20.5%) and dominant in spring (34.9 ± 19.9%), was represented by primary sugars (fructose, galactose and sucrose), normal chain diacids (oxalic (C2) to azelaic (C9)) and their oxidative precursors (ωC3, 4-oxobutanoic (ωC4) and 5-oxopentanoic (ωC5) acids). The photochemical formation of SOA in the gas phase was characteristic mostly for the summer season, accompanied by higher temperatures, global radiation and O3 concentrations, and lower RH.Additionally, background factor was resolved, which represents compounds with no distinctive seasonal variation and can therefore be of both anthropogenic and biogenic origin and contained mainly less oxidized compounds (methylglyoxal (MeGly), glyoxal (Gly), glyoxylic acid (ωC2) and pyruvic acid (Pyr)).

Comparison of vertical and horizontal atmospheric deposition of nitrate at Central European mountain-top sites during three consecutive winters

Nitrogen (N) deposition, a key process of atmospheric self-cleaning, represents an important pathway for nutrients and pollutants to ecosystems. Enhanced N deposition flux contributes to acidification, eutrophication and loss of biodiversity. N-NO3− concentrations in rime and snow were measured at 10 Czech plots situated in borderline mountains in 2009–2011 winters. The results were put in context with data-driven geostatistical modelling results of annual wet vertical and horizontal deposition. Our hypotheses were that: (i) rime and snow would be more polluted in the highly industrialized north than in the south, (ii) the N-NO3− concentrations would differ in the three winters studied, and (iii), that N-NO3− rime deposition is not negligible in Central European mountain ranges. Our results indicated that winter N-NO3− concentrations were significantly higher in rime than in snow and that there were much larger between-site differences in N-NO3− concentrations for rime than for snow. Relatively large differences were found between individual years. Atmospheric input of N-NO3− in winter was dominated by vertical deposition, i.e., snow. Modelled results showed that mean winter rime deposition corresponded to about 6–25 %, and mean winter snow deposition made up 25–72.5 % of mean annual N-NO3− wet-only deposition. Model N-NO3−occult deposition estimated from throughfall and total (wet and dry) deposition is highly uncertain, however: N throughfall is not a relevant proxy for estimation of realistic total N deposition due to N exchange between the tree canopy and atmosphere.

Long-Term Application of Organic Fertilizers in Relation to Soil Organic Matter Quality

The quality of soil organic matter plays a central role in soil structure, carbon sequestration and pollutant immobilization. The effect of 16–23 years of fertilization on the quality of soil organic matter was studied in field experiments at ten experimental sites in Central Europe. Soil samples were collected in 2016 after barley harvest. Six crops were rotated: pea–canola–winter wheat–spring barley–beet/potato–spring barley. Six treatments were studied: unfertilized control, mineral fertilization (NPK), farmyard manure, farmyard manure + NPK, straw incorporation, and straw incorporation + NPK. Although carbon input did not significantly correlate with any soil organic carbon fractions, the C/N ratio of applied organic fertilizers significantly correlated with the content of humic acid carbon (C-HA), the C-HA/C-FA ratio and humification index in soil. The combination of farmyard manure + NPK resulted in a higher humic acid carbon content in soil, humification rate, and humification index compared to the application of NPK, straw return, and the combination of straw return + NPK. Although straw return led to a lower E4/E6 (A400/A600, Q4/6) ratio compared to farmyard manure application, the C-HA/C-FA ratio was unchanged among these treatments. The application of farmyard manure with and without the addition of NPK led to higher values of carbon sequestration efficiency in soil compared to the straw return with and without the addition of NPK.

Late La Tène horse equipment of the Scordisci - trefoil-shaped terret rings from Eastern Croatia

The various Late La T?ne items of horse equipment found at the sites of the Scordisci include trefoil-shaped terret rings made of copper alloy. Two shape types have been identified; the much more numerous type has a rounded, protruding and decorated plate. These terret rings have parallels in the south-eastern Alpine region and at sites in Central Europe; their abundance at the sites of the Scordisci probably indicates that they were made in local workshops. Just like other Late La T?ne items of horse equipment, these terrets can be associated with mounted warriors, who had the most prominent position in communities.

δ26Mg, δ44Ca and 87Sr/86Sr isotope differences among bedrock minerals constrain runoff generation in headwater catchments: An acidified granitic site in Central Europe as an example

Magnesium, calcium and strontium isotope systematics were studied in a Central European headwater catchment underlain by granite. The Uhlirska catchment (Czech Republic) is recovering from acidification following 40 years of acid rain. A combination of isotope and non-isotope data was used to constrain the origin of base cations in runoff. Whole-rock δ26Mg, δ44Ca values and 87Sr/86Sr ratios were complemented by isotope analysis of apatite, biotite, plagioclase, orthoclase and titanite. Isotope composition of Mg, Ca and Sr in precipitation, throughfall and runoff was monitored for 12 months.Soil, soil solutions and Norway spruce tissues were also analyzed. Non-isotope data included a 24-year time-series of input/output Mg and Ca fluxes. Biotite was the likely main source of geogenic Mg. Apatite and plagioclase were the likely main sources of geogenic Ca, and plagioclase was the likely main source of geogenic Sr. Magnesium in biotite was isotopically too heavy to dominate runoff. Calcium in apatite and plagioclase was isotopically indistinguishable from whole-rock Ca and could play a major role in runoff generation. Plagioclase had a significantly lower 87Sr/86Sr ratio than bulk bedrock, close to the low 87Sr/86Sr ratio of runoff. Plagioclase weathering was consistent with a sizeable geogenic Sr contribution to runoff but if only bulk-rock 87Sr/86Sr was considered predominance of geogenic Sr in runoff would be unlikely. Higher Mg, Ca and Sr runoff fluxes, compared to deposition, suggested geogenic control of runoff. A decrease in runoff fluxes of Mg and Ca coincided with a decrease in deposition fluxes but there may not be a causal relationship pointing to a large atmospheric contribution of base cations to runoff. Decreasing fluxes of base cations via runoff were mostly related to decreasing sulfate export accompanying retreat of acidification. Mg/Ca/Sr isotope systematics at Uhlirska are discussed in light of analogous data from four other headwater catchments.

SOCIETY IN TRANSITION: CULTURAL CHANGE IN THE EARLY BRONZE AGE CEMETERY AT NIŽNÁ MYŠL’A IN THE LIGHT OF ABSOLUTE CHRONOLOGY

ABSTRACTThe article presents the results of research on the absolute chronology of the Nižná Myšľa cemetery. Due to its scale and location in a key region of the Carpathian Basin, it should be considered one of the most important Early Bronze Age sites in Central Europe. Many years of archaeological research have so far failed to provide adequate data on absolute chronology. This text presents the results of statistical and spatial analyses on a series of newly acquired 14C dates. They allowed us to present a model of the spatial and chronological development of the funerary space and to capture the stage of significant cultural change associated with the adoption of a new raw material—bronze.

Interdisciplinary Investigations of the Neolithic Circular Ditch Enclosure of Velm (Lower Austria)

Middle Neolithic circular enclosures, known as Kreisgrabenanlage (KGA), are the oldest known monumental sites in Central Europe, dating roughly to 4850–4600/4500 BC. These large prehistoric monuments are mainly discovered by aerial archaeology and have been investigated by geophysical prospection and archaeological excavations since the 1960s. The site of Velm (Lower Austria) was discovered by aerial photographs in 2001. Due to its unusual location on a flat gravel plateau, the enclosure has become the object of intensive interdisciplinary research in recent years. In 2016, two motorized ground-penetrating radar (GPR) surveys were conducted, resulting in a detailed three-dimensional dataset visualizing the circular ditches, palisades and dwellings of an adjacent settlement. The high contrast between the gravel sediments and the humic earthen backfill of the ditches, palisades and individual postholes resulted in a highly detailed visualization of the Middle Neolithic monument. Based on this survey, selected structures were investigated by targeted archaeological excavations to evaluate the GPR results and to take samples for radiocarbon dating. This paper presents a synopsis of all the methods used. An integrated interpretation of aerial photo information, magnetometry and GPR is conducted, and it is shown to what extent these could be verified by the targeted archaeological excavation. By a detailed analysis of all applied archaeological prospection methods, it is now possible to interpret the monument in its entirety and confirm its dating to the Middle Neolithic Lengyel cultural complex.

Chemically speciated mass size distribution, particle density, shape and origin of non-refractory PM&amp;lt;sub&amp;gt;1&amp;lt;/sub&amp;gt; measured at a rural background site in central Europe

Abstract. Seasonal variability of non-refractory PM1 (NR-PM1) was studied at a rural background site (National Atmospheric Observatory Košetice – NAOK) in the Czech Republic to investigate the effect of regional and long-range atmospheric transport in central Europe. NR-PM1 measurements were performed by compact time-of-flight aerosol mass spectrometry (C-ToF-AMS), and the chemically speciated mass size distributions, density, shape, and origin were discussed. Average PM1 concentrations, calculated as the sum of the NR-PM1 and the equivalent black carbon (eBC) concentrations measured by an aethalometer (AE), were 8.58 ± 3.70 µg m−3 in summer and 10.08 ± 8.04 µg m−3 in winter. Organics were dominant during both campaigns (summer/winter: 4.97 ± 2.92/4.55 ± 4.40 µg m−3), followed by SO42-in summer (1.68 ± 0.81/1.36 ± 1.38 µg m−3) and NO3- in winter (0.67 ± 0.38/2.03 ± 1.71 µg m−3). The accumulation mode dominated the average mass size distribution during both seasons, with larger particles of all species measured in winter (mode diameters: Org: 334/413 nm, NO3-: 377/501 nm, SO42-: 400/547 nm, and NH4+: 489/515 nm) indicating regional and long-range transport. However, since the winter aerosols were less oxidized than the summer aerosols (comparing fragments f44 and f43), the importance of local sources in the cold part of the year was still enough to be considered. Although aged continental air masses from the south-east (SE) were rare in summer (7 %), they were related to the highest concentrations of PM1, eBC, and all NR-PM1 species, especially SO42- and NH4+. In winter, slow continental air masses from the south-west (SW) (44 %) were linked to inversion conditions over central Europe and were associated with the highest concentrations among all NR-PM1 species as well as PM1 and eBC. Average PM1 material density (ρm) corresponded to higher inorganic contents in both seasons (summer: ∼ 1.30 g cm−3 and winter: ∼ 1.40 g cm−3). During episodes of higher mass concentrations ρm ranged from 1.30–1.40 g cm−3 in summer and from 1.30–1.50 g cm−3 in winter. The dynamic shape factors (χ) decreased slightly with particle mobility diameter (Dm) in both seasons. This study provides insights into the seasonal effects and air mass variability on aerosol particles, focusing on episodes of high mass and number concentrations measured at a central European rural background site.

Diverse Effects of Climate, Land Use, and Insects on Dung and Carrion Decomposition

Land-use intensification and climate change threaten ecosystem functions. A fundamental, yet often overlooked, function is decomposition of necromass. The direct and indirect anthropogenic effects on decomposition, however, are poorly understood. We measured decomposition of two contrasting types of necromass, rat carrion and bison dung, on 179 study sites in Central Europe across an elevational climate gradient of 168–1122 m a.s.l. and within both local and regional land uses. Local land-use types included forest, grassland, arable fields, and settlements and were embedded in three regional land-use types (near-natural, agricultural, and urban). The effects of insects on decomposition were quantified by experimental exclusion, while controlling for removal by vertebrates. We used generalized additive mixed models to evaluate dung weight loss and carrion decay rate along elevation and across regional and local land-use types. We observed a unimodal relationship of dung decomposition with elevation, where greatest weight loss occurred between 600 and 700 m, but no effects of local temperature, land use, or insects. In contrast to dung, carrion decomposition was continuously faster with both increasing elevation and local temperature. Carrion reached the final decomposition stage six days earlier when insect access was allowed, and this did not depend on land-use effect. Our experiment identified different major drivers of decomposition on each necromass form. The results show that dung and carrion decomposition are rather robust to local and regional land use, but future climate change and decline of insects could alter decomposition processes and the self-regulation of ecosystems.

Seed Dispersal by Ants in Three Early-Flowering Plants.

Simple SummaryMyrmecochory is seed dispersal of numerous plant species mediated by ants. We investigate ant–plant interactions under field conditions across two study sites in Central Europe. Three obligatory myrmecocohrous plants are chosen for the experiments: snowdrop Galanthus nivalis, hollow root Corydalis cava and European wild ginger Asarum europaeum. We experimentally alter diaspore morphology and record seed removal rates across five treatments: elaiosomes without seeds, diaspore without elaiosome, 1/2 elaiosome + diaspore, 1/2 diaspore + elaiosome and control. Elaiosomes of European wild ginger constitute about 30% of diaspore weight, elaiosomes of snowdrop constitute 13% and elaiosomes of hollow root constitute only 7.5%. Diaspore/elaiosome removal rates are highest in European wild ginger (34%), followed by hollow root (26%) and snowdrop (10%). Only two ants interact with diaspores, the acorn ant Temnothorax crassispinus and the red ant Myrmica ruginodis. Ants respond to elaiosome/seed ratio by removing elaiosomes without diaspores most frequently, followed by 1/2 diaspore + elaiosome, control, diaspores without elaiosomes and 1/2 elaiosome with diaspore. Plants do not effectively manipulate ant behavior and no dispersal benefits from interactions with ants are observed.Interactions between ants and plants vary from being occasionally beneficial to neutral and negative. Ant-mediated dispersal of obligatory myrmecochorous plants is considered mutualistic interaction, providing benefits to plants in terms of seed dispersal. Ants are rewarded by providing elaiosome, sugar, lipid and protein-rich appendages attached to seeds (diaspores). We experimentally examine rates of diaspore removal rates among three species of plants (snowdrop Galanthus nivalis, hollow root Corydalis cava and European wild ginger Asarum europaeum) under field conditions in two study sites in Central Europe. Diaspore morphology is altered by manipulating both elaiosome and seed size. The small-sized acorn ant Temnothorax crassispinus interacts with the snowdrop and hollow root and the moderately-sized red ant Myrmica ruginodis interacts with European wild ginger. Experimental manipulation with elaiosomes yields largely non-significant results. Diaspore removal rates are generally low (snowdrop 10%, hollow root 26%, European wild ginger 34%) probably due to the small size of ants relative to heavy diaspores. Many ants are observed to consume elaiosomes in situ (cheating). We conclude that ant–plant relationships in this case are not mutualistic but rather neutral/slightly negative, because the plants do not obtain any apparent benefits from their interactions with ants.

Soil water availability and branch age explain variability in xylem safety of European beech in Central Europe

Xylem embolism resistance has been identified as a key trait with a causal relation to drought-induced tree mortality, but not much is known about its intra-specific trait variability (ITV) in dependence on environmental variation. We measured xylem safety and efficiency in 300 European beech (Fagus sylvatica L.) trees across 30 sites in Central Europe, covering a precipitation reduction from 886 to 522 mm year−1. A broad range of variables that might affect embolism resistance in mature trees, including climatic and soil water availability, competition, and branch age, were examined. The average P50 value varied by up to 1 MPa between sites. Neither climatic aridity nor structural variables had a significant influence on P50. However, P50 was less negative for trees with a higher soil water storage capacity, and positively related to branch age, while specific conductivity (Ks) was not significantly associated with either of these variables. The greatest part of the ITV for xylem safety and efficiency was attributed to random variability within populations. We conclude that the influence of site water availability on P50 and Ks is low in European beech, and that the high degree of within-population variability for P50, partly due to variation in branch age, hampers the identification of a clear environmental signal.

Local traditional ecological knowledge about hay management practices in wetlands of the Biebrza Valley, Poland

BackgroundThe Biebrza Valley is one of the largest complexes of wetlands (floodplain and percolation mire) and conservation sites in Central Europe. Local communities have managed the area extensively for subsistence and farming purposes for centuries; nonetheless, since the 1960s, hand mowing and livestock grazing have been gradually ceasing due to the intensification of farming, and wetlands have undergone natural succession. Currently, the protection of this vast ecosystem is challenging. Despite its remarkable cultural origin, the complexity of the traditional practices and knowledge of local people have never been studied comprehensively. Therefore, we found it urgent to explore if traditional ecological knowledge that could be used in conservation management of the area still exists among the local community.MethodsWe interviewed 42 inhabitants of seven villages located in the Lower Basin of the Biebrza Valley (NE-Poland) in the consecutive years 2018–2020. We applied semi-structured, repeated interviews with farmers (aged 29–89), each lasting several hours. By using different ethnoecological methods (visual stimuli, walks in wetlands, co-mapping of the area), we explored traditional knowledge on the plants, landscape and traditional management of wetlands.ResultsFarmers from the oldest generation, who used to manage wetlands with scythes, shared the deepest ecological knowledge. Local people divided wetlands into zones differentiated by vegetation type and hay quality. Depending on plant composition, people managed wetlands under a mixed regime: mowing once or twice a year during periods that ensured good hay quality and pasturing various livestock: cattle, horses, sheep, pigs and fowl. We identified at least 50 plant ethnospecies, which were described exhaustively by their habitat, morphological features, and mowing and grazing value.ConclusionsThe local community in the Biebrza Valley shared a deep traditional ecological knowledge and had a good memory of traditional farming practices. Research confirmed the unquestionable cultural origin of the local ecosystem, therefore in conservation endeavours the area should be treated first and foremost as a cultural landscape. The documented exceptional local perception of the wetland landscape, elements of traditional knowledge and complex farming practices should be considered for inclusion into conservation management, and cooperation with the local community should also be taken into account.