Southwestern Germany Research Articles

A Planning Support System for Monitoring Aging Neighborhoods in Germany

Many single-family homes built in Germany in the first decades following the Second World War are now occupied by elderly residents. If local conditions are unfavorable, a large number of these buildings may enter the real estate market in a short period of time and put pressure on the local housing market. Planners and decision-makers therefore need detailed spatiotemporal information about these neighborhoods to effectively address and counteract such developments. We present the design and implementation of a planning support system that can generate the required information. The architecture of this newly developed software consists of a composite, multitier framework to perform the complex tasks of data importation, data processing, and visualization. Legally mandated municipal population registers provide the key data for the calculation of indicators as a base for spatiotemporal analyses and visualizations. These registers offer high data quality in terms of completeness, logical consistency, spatial, and temporal and thematic accuracy. We demonstrate the implemented method using population data from a local government in a rural area in southwestern Germany. The results show that the new tool, which relies on open software components, is capable to identify and prioritize areas with particularly high levels of problem pressure. The tool can be used not only for analyses in a local context, but also at a regional level.

Comparing a common clavicle maturation-based age estimation method to ordinary regression analyses with quadratic and sex-specific interaction terms in adolescents

Established methods of age estimation are based on correlating defined maturation stages of bony structures with tables representing the observed range of biological ages in the majority of cases. In this retrospective monocentric study in southwestern Germany, common age estimation methodology was assessed in n = 198 subjects at the age of 25 or younger by analyzing the influence of age, quadratic age, biological sex and age-sex interaction on the ossification stages of the medial epiphysis fugue. Three readers (ICC ≥ 0.81 for left/right side) evaluated routine care computed tomography images of the clavicle with a slice thickness of 1 mm. By using least square regression analyses, to determine the real biological age a quadratic function was determined corrected for the age estimated by established methods and sex (R2 = 0.6 each side), reducing the mean absolute error and root mean squared error in the age estimation of women (2.57 and 3.19) and men (2.57 and 3.47) to 1.54 and 1.82 for women, and 1.54 and 2.25 for men. In women, the medial clavicle epiphysis seem to fuse faster, which was particularly observable from approximately 18 years of age. Before that age, the estimation method was relatively close to the ideal correlation between assessed and real age. To conclude, the presented new method enables more precise age estimation in individuals and facilitates the determination and quantification of additional variables, quantifying their influence on the maturation of the medial clavicle epiphysis based on the established ossification stages.

Rope making in the Aurignacian of Central Europe more than 35,000 years ago.

Evidence for the manufacture and use of fiber technology such as rope and twine is rare in the Paleolithic, despite the widely held view that such artifacts were in regular use during the Pleistocene. On the basis of the discovery of a more than 35,000-year-old perforated baton made from mammoth ivory at Hohle Fels Cave in Ach Valley of southwestern Germany together with experimental studies, we are now able to demonstrate one way people of the early Upper Paleolithic manufactured rope. This work contributes to our understanding of the evolution of technology, cooperative work, and Paleolithic social organization.

Deeply supervised network for airborne LiDAR tree classification incorporating dual attention mechanisms

ABSTRACT Accurately identifying tree species is crucial in digital forestry. Several airborne LiDAR-based classification frameworks have been proposed to facilitate work in this area, and they have achieved impressive results. These models range from the classification of characterization parameters based on feature engineering extraction to end-to-end classification based on deep learning. However, in practical applications, the loud feature noises of a single sample at varying vertical heights can cause misjudgment between intraspecific samples, thereby limiting classification accuracy. This may be exacerbated by the scanning conditions and geographic environment. To address this challenge, a deeply supervised tree classification network (DSTCN) is designed in this article, which introduced a height-intensity dual attention mechanism to deliver improved classification performance. DSTCN takes the histogram feature descriptors of each tree slice as the input vector and considers the features of each slice in combination with its height and intensity information, utilizing slice features with different information gains more effectively, and removing the accuracy limitations imposed by feature noise at varying vertical heights. Experimental results from the classification of seven tree species in a mixed forest in Baden-Württemberg, southwestern Germany indicate that DSTCN (MAF = 0.94, OA = 0.94, Kappa = 0.93, FISD = 0.02) outperforms the two commonly used methods, based on Point Net++ (MAF = 0.88, OA = 0.88, Kappa = 0.86, FISD = 0.08) and BP Net (MAF = 0.86, OA = 0.87, Kappa = 0.85, FISD = 0.06) respectively, in terms of accuracy, stability, and robustness. This method integrates feature engineering and deep network models to achieve precise and balanced classification outcomes of tree species. The simplified design enables efficient forestry decision-making and presents innovative ideas and a method for employing airborne LiDAR technology in tree species identification of large-scale multi-layer mixed stands.

Forest structure and heterogeneity increase diversity and alter composition of host–parasitoid networks

Abstract Antagonistic host–parasitoid interactions can be quantified using bipartite and metanetworks, which have the potential to reveal how habitat structural elements relate to this important ecosystem function. Here, we analysed the host–parasitoid interactions of cavity‐nesting bees and wasps, as well as their abundance, diversity and species richness with forest structural elements from 127 forest research plots in southwestern Germany. We found that parasitoid abundance, diversity and species richness all increase with host abundance, a potential mediator between parasitoids and forest structure. Both parasitoid abundance and diversity increased with stand structural complexity, possibly mediated by the abundance of hosts. In addition, parasitoid abundance increased with increasing standing deadwood and herb cover. The bipartite networks of host–parasitoid interactions showed higher connectance with increasing standing deadwood, herb cover and host abundance. Analyses of interactions within the host–parasitoid metanetwork revealed that increasing host abundance and decreasing canopy cover diversify the suites of interactions present at the plot level. These results demonstrate that forest structural elements can improve the stability and resilience of host–parasitoid networks by promoting parasitoids and diversifying interactions in ecological networks.

INVASIVE INSECT SPECIES CYDALIMA PERSPECTALIS (WALKER, 1859): GLOBAL DISTRIBUTION, INVASION IN UKRAINE AND DAMAGE IN CHERNIVTSI REGION

Invasions of species into ecosystems cause their transformation and, in certain cases, their degradation. The study was carried out to determine the extent of the invasion of Cydalima perspectalis (Walker, 1859). For this purpose, the following aspects were analyzed: distribution of the species in different countries of the worldі, history of invasion of the pest in Ukraine, degree of damage to plantations of different box (Buxus L.) species and colony density in certain areas. The chronology of the distribution of C. perspectalis was studied using literature sources and international databases: Global Biodiversity Information Facility (GBIF), Delivering Alien Invasive Species Inventories for Europe (DAISIE), European and Mediterranean Plant Protection Organization (EPPO). The information on the history of the species' invasion in Ukraine and in particular in the Chernivtsi region was found in the literature, using the database of the National Biodiversity Information Network (UkrBIN), through questionnaires and personal observations using the route method (counting the number of C. perspectalis on a certain route). The degree of damage to Buxus sp. shrubs was determined visually using a scale. The density of C. perspectalis in each area was assessed by total counts and direct counts in situ with a parallel assessment of habitat size. It was found that the expansion of C. perspectalis beyond its native range began in 2006 from southwestern Germany. In 15 years, the species has occupied the territories of about 40 mainland and island countries of the North American and European continents. Since 2014, after the invasion of the Zakarpattia region, C. perspectalis has begun to spread throughout the Ukrainian territories. Currently, the secondary range of the species is represented by 14 regions. The presence of C. perspectalis has been detected in 16 settlements of Chernivtsi region, where the degree of damage to box shrubs is mostly severe. The density of caterpillars on most bushes is up to 100 individuals/m2, which indicates the high damage of the species. Key words: Cydalima perspectalis (Walker, 1859), invasive species, damage, expansion.

The role of fire in the Medieval and Early Modern landscape of Bad Waldsee within the broader context of the pre-Alpine forelands of south-western Germany

Fire, an important element of human land use strategies, was part of many early industrial activities but also of burning incidents that significantly impacted settlement structures and development. The spatial proximity of the historically well-documented medieval town and sediment archive deposited in its central lake (Stadtsee) was taken to investigate the interplay of fire and socio-environmental developments during the preindustrial phase of 750−150 bp (ad 1200–1800). The burning episodes were detected using the sediment macroscopic charcoal record (> 150 μm) and were interpreted considering sedimentological, palynological, and historical evidence. Macro-charcoal analysis revealed two main phases of biomass burning: a late Medieval one (653−533 cal bp ), followed by a distinct fire-free interval, and a second Modern Times phase (313 cal bp until today). During the late Medieval times and after ad 1750 (200 cal bp) low-magnitude local fires coincided with high-intensity land use pressure. Major historical events like the Thirty Years’ War and the fire incident near the town (ad 1386, 174 cal bp) were also documented by the charcoal sedimentary record. The specific terrain morphology and the town microclimate impacted the chance of whether certain local burning patterns were detectable at all. This study demonstrates that during the Medieval period to the present day, fire events, mainly anthropogenic, were coupled with the main vegetation developments. Anthropogenic fire was an inseparable part of the Bad Waldsee landscape, as also recorded historically by the town archives.

Pesticide Mixtures in Surface Waters of Two Protected Areas in Southwestern Germany

Pesticides enter non-target surface waters as a result of agricultural activities and may reach water bodies in protected areas. We measured in southwestern Germany pesticide concentrations after heavy rainfalls in streams of a drinking water protection area near Hausen (Freiburg) and in the catchment of the Queich (Landau), which originates from the biosphere reserve Palatinate Forest. On average, 32 (n = 21) and 21 (n = 10) pesticides were detected per sample and event in the area of Hausen (n = 56) and in the Queich catchment (n = 17), respectively. The majority of pesticides detected in > 50% of all samples were fungicides, with fluopyram being detected throughout all samples. Aquatic invertebrates exhibited highest risks with 16.1% of samples exceeding mixture toxicity thresholds, whereas risks were lower for aquatic plants (12.9%) and fish (6.5%). Mixture toxicity threshold exceedances indicate adverse ecological effects to occur at half of sites (50%). This study illustrates the presence of pesticide mixtures and highlights ecological risks for aquatic organisms in surface waters of protected areas in Germany.

PFΔScreen - an open-source tool for automated PFAS feature prioritization in non-target HRMS data.

Per- and polyfluoroalkyl substances (PFAS) are a huge group of anthropogenic chemicals with unique properties that are used in countless products and applications. Due to the high stability of their C-F bonds, PFAS or their transformation products (TPs) are persistent in the environment, leading to ubiquitous detection in various samples worldwide. Since PFAS are industrial chemicals, the availability of authentic PFAS reference standards is limited, making non-target screening (NTS) approaches based on high-resolution mass spectrometry (HRMS) necessary for a more comprehensive characterization. NTS usually is a time-consuming process, since only a small fraction of the detected chemicals can be identified. Therefore, efficient prioritization of relevant HRMS signals is one of the most crucial steps. We developed PFΔScreen, a Python-based open-source tool with a simple graphical user interface (GUI) to perform efficient feature prioritization using several PFAS-specific techniques such as the highly promising MD/C-m/C approach, Kendrick mass defect analysis, diagnostic fragments (MS2), fragment mass differences (MS2), and suspect screening. Feature detection from vendor-independent MS raw data (mzML, data-dependent acquisition) is performed via pyOpenMS (or custom feature lists) with subsequent calculations for prioritization and identification of PFAS in both HPLC- and GC-HRMS data. The PFΔScreen workflow is presented on four PFAS-contaminated agricultural soil samples from south-western Germany. Over 15 classes of PFAS (more than 80 single compounds with several isomers) could be identified, including four novel classes, potentially TPs of the precursors fluorotelomer mercapto alkyl phosphates (FTMAPs). PFΔScreen can be used within the Python environment and is easily automatically installable and executable on Windows. Its source code is freely available on GitHub ( https://github.com/JonZwe/PFAScreen ).

New insights into Magdalenian subsistence at Petersfels (Hegau Jura, southwestern Germany)

At Petersfels (Hegau Jura, southwestern Germany), one of the most prolific Magdalenian sites in Central Europe, nearly one hundred years of excavation and research has revealed an exceptional record of human occupation from 15,000 years ago. Unstudied faunal remains (n = 3256) from a 16 m2 area in front of the cave (P6 excavation area) provide an opportunity to assess the site from a modern perspective. Reindeer (Rangifer tarandus) dominate the assemblage followed by hare (Lepus sp.), horse (Equus ferus), and ptarmigan (Lagopus sp.). The faunal remains are well-preserved and exhibit abundant cut marks, impacts, and green breaks, attesting to the highly anthropogenic nature of the assemblage. Carnivore damage is also present, although to a lesser extent, and suggests that fox- and wolf-sized carnivores gained secondary access by exploiting human garbage. Evidence for the transport of reindeer limbs, osseous artifacts, and other remnants of material culture indicates hunter-gatherers used P6 for habitation and the secondary processing of faunal remains, especially butchery, marrow extraction, and tool production. Overall, our results support prior interpretations of the site as a fall-winter aggregation camp and provide new information on human subsistence practices, the role of carnivores, and the use of space by Magdalenian people.

A comparison of seven innovative robotic weeding systems and reference herbicide strategies in sugar beet (Beta vulgaris subsp. vulgaris L.) and rapeseed (Brassica napus L.)

AbstractMore than 40 weeding robots have become commercially available, with most restricted to use in crops or fallow applications. The machines differ in their sensor systems for navigation and weed/crop detection, weeding tools and degree of automation. We tested seven robotic weeding systems in sugar beet and winter oil‐seed rape in 2021 and 2022 at two locations in Southwestern Germany. Weed and crop density and working rate were measured. Robots were evaluated based on weed control efficacy (WCE), crop stand loss (CL), herbicide savings and treatment costs. All robots reduced weed density at least equal to the standard herbicide treatment. Band‐spraying and inter‐row hoeing with RTK‐GPS guidance achieved 75%–83% herbicide savings. When hoeing and band spraying were applied simultaneously in one pass, WCE was much lower (66%) compared to the same treatments in two separate passes with 95% WCE. Hoeing robots Farmdroid‐FD20®, Farming Revolution‐W4® and KULTi‐Select® (+finger weeder) controlled 92%–94% of the weeds. The integration of Amazone spot spraying® into the FD20 inter‐row and intra‐row hoeing system did not further increase WCE. All treatments caused less than 5% CL except for the W4‐robot with 40% CL and the combination of conventional inter‐row hoeing and harrowing (21% CL). KULT‐Vision Control® inter‐row hoeing with the automatic hydraulic side‐shift control resulted in 80% WCE with only 2% CL. Due to the low driving speed of maximum 1 km h−1 of hoeing robots with in‐row elements, treatment costs were high at 555–804 € ha−1 compared to camera‐guided inter‐row hoeing at 221 € ha−1 and broadcast herbicide application at 307–383 € ha−1. Even though the costs of robotic weed management are still high, this study shows that robotic weeding has become a robust, and effective weed control method with great potential to save herbicides in arable and vegetable crops.

PyESDv1.0.1: an open-source Python framework for empirical-statistical downscaling of climate information

Abstract. The nature and severity of climate change impacts vary significantly from region to region. Consequently, high-resolution climate information is needed for meaningful impact assessments and the design of mitigation strategies. This demand has led to an increase in the application of empirical-statistical downscaling (ESD) models to general circulation model (GCM) simulations of future climate. In contrast to dynamical downscaling, the perfect prognosis ESD (PP-ESD) approach has several benefits, including low computation costs, the prevention of the propagation of GCM-specific errors, and high compatibility with different GCMs. Despite their advantages, the use of ESD models and the resulting data products is hampered by (1) the lack of accessible and user-friendly downscaling software packages that implement the entire downscaling cycle, (2) difficulties reproducing existing data products and assessing their credibility, and (3) difficulties reconciling different ESD-based predictions for the same region. We address these issues with a new open-source Python PP-ESD modeling framework called pyESD. pyESD implements the entire downscaling cycle, i.e., routines for data preparation, predictor selection and construction, model selection and training, evaluation, utility tools for relevant statistical tests, visualization, and more. The package includes a collection of well-established machine learning algorithms and allows the user to choose a variety of estimators, cross-validation schemes, objective function measures, and hyperparameter optimization in relatively few lines of code. The package is well-documented, highly modular, and flexible. It allows quick and reproducible downscaling of any climate information, such as precipitation, temperature, wind speed, or even short-term glacier length and mass changes. We demonstrate the use and effectiveness of the new PP-ESD framework by generating weather-station-based downscaling products for precipitation and temperature in complex mountainous terrain in southwestern Germany. The application example covers all important steps of the downscaling cycle and different levels of experimental complexity. All scripts and datasets used in the case study are publicly available to (1) ensure the reproducibility and replicability of the modeled results and (2) simplify learning to use the software package.

Impact of different establishment methods for summer-sown cover crops in Southwestern Germany on their weed suppression properties

Early establishment of cover crops (CCs) is essential for attaining successful weed suppression in the autumn-to-spring period. Due to reduced precipitation and extended periods of drought in the summer within temperate zones, the establishment of CCs poses challenges. Three methods of cover crop (CC) establishment were tested: 1) preharvest sowing 10 days before harvest of cash crop (PreHa); 2) no-till sowing directly after harvest of cash crop (NoTi) and 3) sowing with reduced tillage 10 days after harvest of cash crop (ReTi). The five CC species black oat (Avena strigosa Schreb.); common buckwheat (Fagopyrum esculentum Moench), phacelia (Phacelia tanacetifolia Benth.), fodder radish (Raphanus sativus var. oleiformis L.) and common vetch (Vicia sativa L.), along with a mixture comprising 20% of all five species, were included as second factor in a three-year field experiment (2020–2022) conducted in South West Germany. One treatment per establishment method was maintained without CCs as a control. Measurements of CC, volunteer cereal and weed density, soil coverage, and dry matter were carried out throughout the autumn-to-late autumn timeframe. On average across all years and CCs, the PreHa and NoTi establishment demonstrated the highest CC dry matter contents of 99 g m−2 and 119 g m−2, respectively, despite lower CC densities. This had a particularly notable impact on weed density in the ReTi variant, which, over the three-year average across all CC treatments, was 5 times higher than in NoTi and PreHa but exhibited a 18–27% smaller volunteer cereal density by comparison, thereby influencing the respective volunteer cereal and weed coverages. Meanwhile, weed and volunteer cereal dry matters were consistent across all establishment methods. The CC mixture exhibited enhanced resilience to fluctuating weather conditions, leading to an overall superior performance across the three-year experimental period and showing highest measured CC dry matters up to 272 g m−2 in 2022. However, the observed effects in the treatments varied considerably depending on the CC species, sowing date, and weather conditions. In summary, this study demonstrates that early CC sowing, whether directly after the cash crop harvest or 10 days before the cash crop is harvested, has a positive impact on CC biomass formation, especially leading to a reduced weed emergence. Additionally, under variable weather conditions, a diverse CC mixture can exhibit a more stable overall performance compared to CC monocultures.

Performance comparison of external IBA and SR-XRF imaging for the study of ivory

The performances of Ion Beam Analysis (IBA) at the New AGLAE accelerator external microfocus beamline and those of Synchrotron Radiation micro-X-Ray Fluorescence (SR-XRF) at the PUMA beamline at the SOLEIL synchrotron are compared for non-invasive characterization of archaeological ivory. Based on the examination of ivory artefacts from the Palaeolithic siteHohle Felsin South-western Germany, the informative value of this combination of methods is evaluated with regard to archaeological questions. Parameters such as depth of information, elemental sensitivity as a function of atomic number and imaging capacity are considered. We obtain an almost complete coverage of the chemical composition of ivory (C to Pb). Rutherford Backscattering Spectrometry (RBS) allows the identification of collagen and PIXE/PIGE provide a higher sensitivity for light elements while SR-XRF offers high resolution imaging for heavier elements. Both facilities provide different depths of information that can be exploited to better distinguish exogenous and endogenous elements.

The Diverse Reticulate Genetic Set-Up of Endangered Gladiolus palustris in Southern Germany Has Consequences for the Development of Conservation Strategies

Gladiolus palustris (marsh Gladiolus) of wet grasslands is an extremely rare and highly endangered species in Central Europe. Ongoing loss of habitat, population fragmentation, drought, and higher mean annual temperatures caused by global warming have all contributed to a severe decline in its population over the past few decades. Additionally, hybridization with other species, such as G. imbricatus and G. illyricus, and genetic depletion may pose a significant threat to the species’ survival. The focus of this study is to characterize major gene pools of the species in southern and southwestern Germany. Using molecular AFLP markers and ITS DNA sequencing, this study shows that past hybridization and introgression in Central Europe are more extensive than previously thought, posing a challenge to conservation strategies targeting taxonomically defined species. The region of the Rhine River in southwestern Germany (Upper Rhine Valley) has seen the emergence of various scattered populations of G. palustris over the past three decades, which are believed to have been introduced by humans. Introduced populations in this area (comprising the German Federal States of Baden–Württemberg and Rhineland–Palatinate) likely descend from a large source population near Lake Constance. Therefore, the study suggests promoting and protecting these new populations, given their long-standing presence in the region. Furthermore, the research proposes that naturally occurring hybrids and introgressed populations should also be the primary target of conservation efforts.

Tracing past extreme floods on an alluvial fan using geophysical surveying

SummarySedimentary units in alluvial fans may record gradual transport and deposition during multiple floods or sediment‐laden flows or, conversely, during few catastrophic events. While outcrops are a valuable source of direct information to constrain past geomorphic and hydrologic processes, such exposures are scarce, especially along aggrading rivers or those that have been subject to recent catastrophic sedimentation. In this context, near‐surface geophysical techniques can constrain the dimensions, internal architecture, composition, and petrophysical properties of different sedimentary units. We consider the Grimmbach alluvial fan in the cuesta landscape of southwestern Germany, which was heavily impacted by sediment and wood loads during a flash flood in 2016; published radiocarbon dates indicate that at least three floods similar to the one in 2016 may have occurred since the 17th century. To test whether and to which detail near‐surface geophysics might reveal the sedimentary legacy of these floods, we survey the Grimmbach alluvial fan using detailed topographic data and geophysical imaging based on electromagnetic induction, electrical resistivity tomography (ERT), and ground‐penetrating radar. Our geophysical results indicate former channel courses and two coarse bar deposits up to 3 m below the surface, which are comparable with the more extensive bar deposits of the 2016 flood. From the ERT models, we interpret coarse, up to 5 m thick, gravel lag overlying bedrock at a maximum depth of 10 m. Our geophysical results also highlight patches of finer materials derived from gradual sedimentation and soil development. Overall, our results show that the Grimmbach alluvial fan may have formed and reshaped during catastrophic flows, which likely caused channel avulsions. Our findings point to the need to reconsider flash flood and debris‐flow hazards in similar headwaters and fans of this seemingly quiescent cuesta landscape in southern Germany.

Foxes in Retrospect—Unraveling Human-Fox Relationships through Fox Tooth Ornaments in the Swabian Jura

Personal ornaments play an important role in our understanding of human cultural and behavioral change during the Upper Paleolithic, providing insights into intangible aspects of human cultural behavior. Some ornament forms are better studied than others, and fox tooth ornaments, despite their frequent occurrence and broad spatiotemporal span, are relatively under-addressed. Here we present the first comprehensive study of 40 perforated fox teeth recovered from four cave sites in southwestern Germany. This region’s rich record of symbolic representations, as well as evidence of long-standing human–fox relationships, make the Swabian Jura an ideal case study for investigations of fox tooth ornaments. By applying a holistic approach, including geometric morphometrics and traceology coupled with experimental archaeology, we show that fox teeth were mostly perforated by bifacial scraping and grooving and were worn as ornaments. We discuss the role of foxes within human socio-symbolic and paleoenvironmental systems during the Upper Paleolithic of the Swabian Jura, and we contextualize our results within the broader context of sites across Europe during the Upper Paleolithic. The data we provide are in line with general trends observed across the continent and offer insight into the role of foxes during the Upper Paleolithic, especially regarding human subsistence, cultural expression, and ornament production.

Massive Fish Kill After the Discharge of Artificial Fertilizer into a Species Rich River in Southwestern Germany: a Conservation Case Study

In the summer of 2015, large amounts of artificial fertilizer containing ammonium nitrate were accidentally discharged into the Jagst River along with water used to extinguish a serious fire. The incident caused a massive fish kill the first 25 km downstream of the spill and impacted fish density along a 50 km stretch of this sensitive and important river. In this study, the long-term effects of the accident on the local fish fauna were investigated, and the implemented restoration measures were evaluated. A majority of fish surviving the immediate effects of the incident exhibited massive gill damage and weakness to infections shortly after the accident, but survival over the following winter appeared unimpaired. Two years after the accident, most survived fish appeared healthy. In 2016, about 9500 individuals (500 kg fish of 11 autochthonous species) were caught in unaffected sections of the river and distributed systematically into severely affected sections. Two control sections were left unstocked. Species diversity and fish density remained low over the first winter 2015/16, but increased in autumn 2016, most likely as a result of systematic stocking measures taken in response to the disaster. Stocking and natural migration were able to restore species diversity back to pre-accident levels in due time, i.e., 36 months, but density remains lower and shows no sign of further recovery. A positive consequence of the catastrophe has been the enactment in the ensuing years of various measures to improve the resilience of the Jagst River. However, connectivity is still lacking in relevant sections of the river and this, in combination with high predation from an increasing population of cormorants, has hampered the recovery of fish stocks. Generalizable conservation measures to mitigate the impact of similar catastrophes are developed and discussed.

Increased bat hunting at polluted streams suggests chemical exposure rather than prey shortage

Streams and their riparian areas are important habitats and foraging sites for bats feeding on emergent aquatic insects. Chemical pollutants entering freshwater streams from agricultural and wastewater sources have been shown to alter aquatic insect emergence, yet little is known about how this impacts insectivorous bats in riparian areas. In this study, we investigate the relationships between the presence of wastewater effluent, in-stream pesticide toxicity, the number of emergent and flying aquatic insects, and the activity and hunting behaviour of bats at 14 streams in southwestern Germany. Stream sites were located in riparian forests, sheltered from direct exposure to pollutants from agricultural and urban areas. We focused on three bat species associated with riparian areas: Myotis daubentonii, M. cf. brandtii, and Pipistrellus pipistrellus. We found that streams with higher pesticide toxicity and more frequent detection of wastewater also tended to be warmer and have higher nutrient and lower oxygen concentrations. We did not observe a reduction of insect emergence, bat activity or hunting rates in association with pesticide toxicity and wastewater detections. Instead, the activity and hunting rates of Myotis spp. were higher at more polluted sites. The observed increase in bat hunting at more polluted streams suggests that instead of reduced prey availability, chemical pollution at the levels measured in the present study could expose bats to pollutants transported from the stream by emergent aquatic insects.

Phosphate Fertilizer Type and Liming Affect the Growth and Phosphorus Uptake of Two Maize Cultivars

In the context of phosphorus (P) exhaustion and low P use efficiency (PUE) in crop production, a field trial was designed on a low-P soil in southwestern Germany in 2020 and 2021 to investigate the effects of P fertilizer type and liming on maize growth and P uptake and PUE. The experimental factors were (i) two P fertilizer types, rock phosphate (RP) and diammonium phosphate (DAP); (ii) lime application, lime and no lime; and (iii) two maize cultivars. The results showed that RP resulted in a lower leaf area index and light interception compared with DAP, a 33% lower silage yield, and a 29% lower P content at harvest. The PUE of RP was 18%, which was 37% lower than DAP. Soil liming reduced shoot biomass and led to 35% less shoot P content at the six-leaf stage. The maize cultivar Stabil expressed higher yielding and P acquisition characteristics. In conclusion, DAP cannot be replaced by placed RP, regardless of the lime application in silage maize production in this study. Future research on the PUE of maize cultivars should also consider root characteristics in response to P fertilizer type and soil pH.