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In recent years, the issue of land consumption or land use has become increasingly important in many areas of our society. Logistics processes in particular take up a lot of space and have a significant impact on the environment. The question is how this use of land can be optimised. Based on a systematic literature review and interviews with experts in the period between May 2021 and July 2021, this paper presents indicators that constitute or influence space-efficient logistics in the context of cooperation. The results show that in addition to the established cooperation characteristics, there are other indicators that are directly related to land use. In the logistics sector, there is strong competitive pressure and, as a result, little trust between companies. It has been shown that with the help of a neutral moderator, the gap between trusting, land-efficient cooperation and one’s own entrepreneurial interests can be narrowed, and cooperation can be profitable for all participants. In addition, digitisation actually does not seem to be sufficient to meet the information needs of a cooperation. The exchange of information not only serves to automate processes, but also makes cooperation more transparent. It shows that legal and municipal requirements need to be developed. It also becomes clear that the indicators have a mutual influence on each other and cannot be considered in isolation when it comes to the actual implementation of a cooperation. By increasing the efficiency of cooperative processes and value creation, it offers the opportunity to make land use more sustainable.
In view of the rapid depletion of natural resources and the associated overloading of the biological ecosystem, the concept of circular business models (CBMs) is increasingly discussed in the literature as well as in business practice. CBMs have the potential to significantly reduce the demand for natural resources. Despite their increasing relevance, the diffusion of CBMs in business practice is largely unexplored. Consequently, this article investigates the extent to which CBMs have already been adopted by large German companies. To answer this question, the annual and sustainability reports of the members of the DAX40 are analyzed for the presence of five specific types of CBMs. Data was gathered for the years 2015 and 2020 in order to describe the development over time. The results show an increasing prevalence of CBMs in the DAX companies. In addition, it is noticeable that CBM types that serve to close material cycles are implemented more frequently than those that decelerate material cycles. In particular Sharing Platforms and Product as a Service stand out due to comparatively low adoption. Potential reasons for these findings are discussed and managerial as well as policy implications suggested.
While recent studies have demonstrated that events are fundamentally climate sensitive, this seems to not be fully considered in event research or corporate event practice. Thus, this study aims to identify the influencing factors that affect the acceptance of climate adaptation measures among decision-makers in the event industry. The analysis was divided into three main parts. First, the existing literature related to climate change in an events context was reviewed. Using 15 semi structured interviews, the findings from this review were then critically discussed with stakeholders in Germany involved in event planning. Finally, explicit climate adaptation measures were proposed and discussed. Based on all findings, there appears to be a low level of awareness of and interest in climate adaptation amongst German event industry players. There is an imminent need for further research on climate adaptation and for decision-makers to better prepare for climate change in order to counteract resulting negative impacts.
Purpose
This study operationalizes risks in stakeholder dialog (SD). It conceptualizes SD as co-produced organizational discourse and examines the capacities of organizers' and stakeholders' practices to create a shared understanding of an organization’s risks to their mutual benefit. The meetings and online forum of a German public service media (PSM) organization were used as a case study.
Design/methodology/approach
The authors applied corpus-driven linguistic discourse analysis (topic modeling) to analyze citizens' (n = 2,452) forum posts (n = 14,744). Conversation analysis was used to examine video-recorded online meetings.
Findings
Organizers suspended actors' reciprocity in meetings. In the forums, topics emerged autonomously. Citizens' articulation of their identities was more diverse than the categories the organizer provided, and organizers did not respond to the autonomous emergence of contextualizations of citizens' perceptions of PSM performance in relation to their identities. The results suggest that risks arise from interactionally achieved occasions that prevent reasoned agreement and from actors' practices, which constituted autonomous discursive formations of topics and identities in the forums.
Originality/value
This study disentangles actors' practices, mutuality orientation and risk enactment during SD. It advances the methodological knowledge of strategic communication research on SD, utilizing social constructivist research methods to examine the contingencies of organization-stakeholder interaction in SD.
While the topic of artificial intelligence (AI) in multinational enterprises has been receiving attention for some time, small and medium enterprises (SMEs) have recently begun to recognize the potential of this new technology. However, the focus of previous research and AI applications has therefore mostly been on large enterprises. This poses a particular issue, as the vastly different starting conditions of various company sizes, such as data availability, play a central role in the context of AI. For this reason, our systematic literature review, based on the PRISMA protocol, consolidates the state of the art of AI with an explicit focus on SMEs and highlights the perceived challenges regarding implementation in this company size. This allowed us to identify various business activities that have been scarcely considered. Simultaneously, it led to the discovery of a total of 27 different challenges perceived by SMEs in the adoption of AI. This enables SMEs to apply the identified challenges to their own AI projects in advance, preventing the oversight of any potential obstacles or risks. The lack of knowledge, costs, and inadequate infrastructure are perceived as the most common barriers to implementation, addressing social, economic, and technological aspects in particular. This illustrates the need for a wide range of support for SMEs regarding an AI introduction, which covers various subject areas, like funding and advice, and differentiates between company sizes.
This chapter examines the integration of Sustainable Development Goal 5 (SDG 5) into identity-based brand management by focusing on Dove’s brand management as a case study. The Dove “Real Beauty” campaign highlights the potential for brands to address gender equality and female empowerment by aligning with pro-female and feminist principles. A narrative literature review shows how the components of identity-based brand management have been observed in scholarly discussions. Despite mixed responses and criticisms, Dove initiated important conversations around beauty standards and gender equality. The chapter emphasizes the need for authenticity, sensitivity, and continuous improvement in integrating SDG 5 into brand management while acknowledging the potential risks and limitations of consumerist therapy and false hopes. Future research could therefore explore diverse brands, industries, and cultural contexts, as well as the role of intersectionality in identity-based brand management.
Spinach is a nitrogen (N)-demanding crop characterized by a shallow root architecture. Especially in the first weeks after sowing, significant N uptake is limited to the uppermost few centimetres of the soil. However, base fertilization is usually based on the soil mineral N (Nmin) concentration in the upper 30 cm. Therefore, the objective of this study was to examine whether the soil sample depth for calculating the base N fertilization can be reduced to the 0-15 cm layer. In seven field trials, conducted during spring, summer and autumn seasons, either a low or high base fertilization dose was applied at sowing. Until top dressing, soil samples were frequently taken in the upper 0-15 and 15-30 cm layers to determine the average Nmin concentration in each layer. Top dressing was applied when the first true leaves had unfurled. With this fertilizer application, the total N supply was aligned between both treatments based on the Nmin concentration in the upper 30 cm of the soil. Aboveground fresh and dry masses were determined after reaching a fresh mass yield of 15-20 t ha‑1 and related to the mean Nmin concentration in the first 3 to 4 weeks of cultivation between sowing and top dressing. It was shown that the Nmin concentration in the upper 0-15 cm of the soil highly reflects the base fertilization rate. By contrast, the Nmin concentration in the 15-30 cm layer remained unaffected. However, the Nmin concentration of both top soil layers can affect fresh and dry mass yield at harvest. Therefore, the entire 0-30 cm soil layer should be considered when calculating the base N fertilization rate in field-grown spinach. Measurements revealed that spinach fresh and dry masses were increased until the N availability of between 54 and 59 kg ha‑1 (0-30 cm) was reached at the seedlings stage, respectively.
The mineralization of soil organic nitrogen (N) and crop residues can significantly contribute to the N supply of vegetable crops. However, short-term mineralization dynamics are difficult to predict. On the other hand, fast-growing crops like spinach are highly sensitive to N shortage. Therefore, in situ soil columns have been tested to estimate the actual N supply via mineralization in field-grown spinach. In ten fertilization trials covered soil columns (20 cm in diameter) were driven into the soil to a depth of 30 cm at the start of the cultivation. Eight columns were repeated in three blocks within a total trial area of 0.10 to 0.25 ha. Net N mineralization was derived by subtracting the soil mineral N concentration (Nmin) in the upper 30 cm before installation from the concentration inside the columns at harvest. For comparison, a balance sheet was calculated for spinach plots receiving no N fertilization (zero plots) as well as fertilized plots and used as a proxy for net N mineralization. In this approach the initial Nmin concentration in the upper 30 cm of the soil, the N supply via irrigation, and fertilization as well as the total aboveground N uptake by spinach and the Nmin residue were considered. By using soil columns, N mineralization was determined with a mean coefficient of variation of 18%. A higher spatial variability of up to 43% was observed when spinach was grown as a second crop. The average net N mineralization rate ranged between 2 kg ha‑1 week‑1 (0-30 cm) in winter-grown spinach and 3-7 kg ha‑1 week‑1 (0-30 cm) in the other seasons. Nitrogen mineralization measured by the soil columns was qualitatively confirmed with the data obtained by the balance sheet. Soil columns enable repeated samplings during the spinach cultivation. In this way, top dressing rates can be adjusted to the actual N supply.
Iron deficiency is still widespread as a major health problem even in countries with adequate food supply. It mainly affects women but also vegans, vegetarians, and athletes and can lead to various clinical pictures. Biofortification of vitamin C-rich vegetables with iron may be one new approach to face this nutritional challenge. However, so far, little is known about the consumer acceptance of iron-biofortified vegetables, particularly in developed countries. To address this issue, a quantitative survey of 1000 consumers in Germany was conducted. The results showed that depending on the type of vegetable, between 54% and 79% of the respondents were interested in iron-biofortified vegetables. Regression analysis showed a relationship between product acceptance, gender, and area of residence. In addition, relationships were found between consumer preferences for enjoyment, sustainability, and naturalness. Compared to functional food and dietary supplements, 77% of respondents would prefer fresh iron-rich vegetables to improve their iron intake. For a market launch, those iron-rich vegetables appear especially promising, which can additionally be advertised with claims for being rich in vitamin C and cultivated in an environmentally friendly way. Consumers were willing to pay EUR 0.10 to EUR 0.20 more for the iron-biofortified vegetables.
Iron deficiency is a global issue and can lead to a variety of clinical pictures. The biofor-tification of vegetables with iron could complement the existing portfolio of iron-rich products, thus improving iron supply in the long term. In order to determine whether the iron-biofortified vegetables could meet this demand and would address appropriate target groups, a quantitative online survey was conducted in Germany. Based on 1000 consumer responses, a cluster analysis was performed. The results showed a four-cluster solution. The first cluster was holistically engaged, the second was fitness-affine but health unconcerned, the third cluster consists frugal eaters with a focus on medical prevention, and the fourth cluster are hedonists. No cluster focused its consumption on iron-enriched products, but instead all developed an individual mix of the three product groups.
Hyperhydricity (HH) is one of the most important physiological disorders that negatively affects various plant tissue culture techniques. The objective of this study was to characterize optical features to allow an automated detection of HH. For this purpose, HH was induced in two plant species, apple and Arabidopsis thaliana, and the severity was quantified based on visual scoring and determination of apoplastic liquid volume. The comparison between the HH score and the apoplastic liquid volume revealed a significant correlation, but different response dynamics. Corresponding leaf reflectance spectra were collected and different approaches of spectral analyses were evaluated for their ability to identify HH-specific wavelengths. Statistical analysis of raw spectra showed significantly lower reflection of hyperhydric leaves in the VIS, NIR and SWIR region. Application of the continuum removal hull method to raw spectra identified HH-specific absorption features over time and major absorption peaks at 980 nm, 1150 nm, 1400 nm, 1520 nm, 1780 nm and 1930 nm for the various conducted experiments. Machine learning (ML) model spot checking specified the support vector machine to be most suited for classification of hyperhydric explants, with a test accuracy of 85% outperforming traditional classification via vegetation index with 63% test accuracy and the other ML models tested. Investigations on the predictor importance revealed 1950 nm, 1445 nm in SWIR region and 415 nm in the VIS region to be most important for classification. The validity of the developed spectral classifier was tested on an available hyperspectral image acquisition in the SWIR-region.
Recording of Low-Oxygen Stress Response Using Chlorophyll Fluorescence Kinetics in Apple Fruit
(2023)
Long-term storage of apples (Malus x domestica, Borkh.) is increasingly taking place under Dynamic Controlled Atmosphere (DCA). The oxygen level is lowered to ≤ 1 kPa O2 and the apples are stored just above the Lower Oxygen Limit (LOL). Low oxygen stress during controlled atmosphere storage can lead to fermentation in apples if oxygen levels are too low. Chlorophyll fluorescence can be used to detect low-oxygen stress at an early stage during storage. The currently available non-imaging fluorescence systems often use the minimal fluorescence (Fo) parameter. In contrast, the use of chlorophyll fluorescence kinetics is insufficiently described. Therefore, this study aimed to gain more knowledge about the response of chlorophyll fluorescence kinetics to low oxygen stress in apples using a fluorescence imaging system. The results show that the kinetic fluorescence curves differ under aerobic and fermentation conditions. The fermentative conditions initiated a decrease in fluorescence intensity upon application of the saturation pulses during exposure to actinic light. This result was made at 18 °C and 2 °C ambient temperatures. Interestingly, the kinetic curve changed at 2 °C before fermentation products accumulated in the apples. Non-photochemical quenching (NPQ) decreased under fermentation conditions in the dark phase after relaxation. Upon entering the dark relaxation phase after Kautsky induction, ɸPSII began to increase. Under atmospheric oxygen conditions, ɸPSII reached values of 0.81 to 0.76, while under fermentation, ɸPSII values ranged from 0.57 to 0.44.
Background
The current development of sensor technologies towards ever more cost-effective and powerful systems is steadily increasing the application of low-cost sensors in different horticultural sectors. In plant in vitro culture, as a fundamental technique for plant breeding and plant propagation, the majority of evaluation methods to describe the performance of these cultures are based on destructive approaches, limiting data to unique endpoint measurements. Therefore, a non-destructive phenotyping system capable of automated, continuous and objective quantification of in vitro plant traits is desirable.
Results
An automated low-cost multi-sensor system acquiring phenotypic data of plant in vitro cultures was developed and evaluated. Unique hardware and software components were selected to construct a xyz-scanning system with an adequate accuracy for consistent data acquisition. Relevant plant growth predictors, such as projected area of explants and average canopy height were determined employing multi-sensory imaging and various developmental processes could be monitored and documented. The validation of the RGB image segmentation pipeline using a random forest classifier revealed very strong correlation with manual pixel annotation. Depth imaging by a laser distance sensor of plant in vitro cultures enabled the description of the dynamic behavior of the average canopy height, the maximum plant height, but also the culture media height and volume. Projected plant area in depth data by RANSAC (random sample consensus) segmentation approach well matched the projected plant area by RGB image processing pipeline. In addition, a successful proof of concept for in situ spectral fluorescence monitoring was achieved and challenges of thermal imaging were documented. Potential use cases for the digital quantification of key performance parameters in research and commercial application are discussed.
Conclusion
The technical realization of “Phenomenon” allows phenotyping of plant in vitro cultures under highly challenging conditions and enables multi-sensory monitoring through closed vessels, ensuring the aseptic status of the cultures. Automated sensor application in plant tissue culture promises great potential for a non-destructive growth analysis enhancing commercial propagation as well as enabling research with novel digital parameters recorded over time.
SimBO is a flexible framework for optimizing discrete event-driven simulations (DES) using sequential optimization algorithms. While specifically designed for Bayesian Optimization (BO) in the context of DES, SimBO can be applied to any black-box problem with other optimization algorithms. The framework consists of four encapsulated components - the black-box problem, the sequential optimization algorithm, a database for experiment configuration and results, and a web-based graphical user interface - that communicate via well-defined interfaces. Each component can be run in different environments, allowing for cooperation between different hardware- and software configurations. In our research context, SimBO’s architecture enabled BO algorithms to be run on a high-performance cluster with GPU support, while the simulation is executed on a local Windows machine using the Simio simulation software. The framework’s flexibility also makes it suitable for evolving from a research-focused tool to a production-ready, cloud-based optimization tool for modern algorithms.
The excitement sparked by the emergence of AI open platforms has encountered significant scrutiny from educators and educational planners, who have raised valid concerns about issues such as plagiarism, testing protocols, and the authenticity of content submitted by students. While these concerns are timely and crucial, it's essential not to overlook other pressing issues that often go unnoticed in the lived educational experience of learners, particularly within the field of social sciences. This paper aims to advocate for a humanistic approach with a focus on education in the generative AI Era.
Semi-natural grasslands (SNGs) are an essential part of European cultural landscapes. They are an important habitat for many animal and plant species and offer a variety of ecological functions. Diverse plant communities have evolved over time depending on environmental and management factors in grasslands. These different plant communities offer multiple ecosystem services and also have an effect on the forage value of fodder for domestic livestock. However, with increasing intensification in agriculture and the loss of SNGs, the biodiversity of grasslands continues to decline. In this paper, we present a method to spatially classify plant communities in grasslands in order to identify and map plant communities and weed species that occur in a semi-natural meadow. For this, high-resolution multispectral remote sensing data were captured by an unmanned aerial vehicle (UAV) in regular intervals and classified by a convolutional neural network (CNN). As the study area, a heterogeneous semi-natural hay meadow with first- and second-growth vegetation was chosen. Botanical relevés of fixed plots were used as ground truth and independent test data. Accuracies up to 88% on these independent test data were achieved, showing the great potential of the usage of CNNs for plant community mapping in high-resolution UAV data for ecological and agricultural applications.
Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.
Green roofs can mitigate negative environmental effects of urban densifcation to some extent, but they are often covered by species-poor Sedum mixtures with a low value for biodiversity. By combining a habitat template and a seedprovenance approach, we review the suitability of plant species from regionally occurring dry sandy grasslands (Koelerio-Corynophoretea) for extensive roof greening in northwestern Germany. Since 2015, we have studied the effects of species introduction on vegetation dynamics on experimental mini-roofs. Treatments included sowing seeds of regional native origin in two densities (1 g and 2 g/m2) and the transfer of raked material from an ancient dry grassland area classifed as Natura 2000 site. The applied raked material contained diaspores of 27 vascular plant species (including seven threatened species) and vegetative fragments of grasslandspecifc mosses and lichens. Since 2018, we have tested more species-rich seed mixtures in a large-scale experiment on a roof of 500 m2 with different engineered green-roof substrates and layering. In 2019, a green roof of 10,200 m2 was established in cooperation with a local enterprise to support regional native biodiversity.
In this chapter, we summarise the most important results of our studies and discuss how to support regional native biodiversity on green roofs.
Methods: Systematic review of randomized controlled trials (RCT). Searches were conducted in five electronic databases. Studies were selected if they included patients with NP over 18 years old treated with aerobic exercise (AE) (e.g., cycling, running, hiking, and walking). The main outcome of interest was pain intensity. Qualitative and quantitative data were extracted. The risk of bias (RoB) was determined using the Cochrane RoB Tool-2 and the overall certainty of the evidence with the GRADE recommendations.
Results: Out of 21,585 initial records screened, a total of six individual studies published in ten manuscripts were included. There was a great heterogeneity between protocols, comparisons, and studies’ results (different magnitudes and directions). When looking at the effect of aerobic exercise versus control groups or other interventions on pain intensity measured with the VAS, not statistically (nor clinical) significant differences between aerobic exercise and control groups (MD [95%CI] 5.16 mm [-6.38, 16.70]) were identified. The combined effect of AE plus other interventions seems to be effective. Strength exercise obtained better effects than aerobic exercises (MD [95%CI]: -11.34 mm [-21.6, -1.09]).
Conclusions: Aerobic exercise presented positive results to reduce pain intensity, and improving disability, and physical and emotional functioning. However, the evidence is restricted, low quality, and heterogeneous.
Methods: The searches were conducted on five electronic databases. RCTs or CTs with patients over 18 years old of both sexes with OFP diagnoses were targeted. The intervention of interest was AE (i.e., walking, cycling, and running), compared to any other conservative and non-conservative therapy. The primary outcome was pain intensity. Risk of bias (RoB) was done with the Cochrane RoB tool (RoB 2). The overall certainty of the evidence was evaluated with GRADE.
Results: Out of 21,585 initial records found in the initial database search, only one study (reported on three manuscripts) was included. The diagnosis of interest was headache plus temporomandibular disorders (TMD). Three treatment groups (strengthening (Str) exercise + manual therapy (MT) (G1); AE + MT + Str exercises (G2); AE (G3)) were compared. The main outcome was pain; the secondary outcomes included disability, strength, anxiety, and quality of life. The combined treatment (AE+MT+Str exercises) had the strongest effect to decrease pain and headache intensity in patients with OFP (SMD: 9.99 [95%CI: 7.19, 12.80].
Conclusions: a multimodal treatment strategy achieved the greatest positive effects on pain and other outcomes in the short/medium term. AE seems to be an important component of this strategy. However, the scientific evidence supporting AE’s isolated effect is limited, indicating a research gap in this scientific field.
1. Flower strips are a fundamental part of agri-environment schemes (AESs) introduced by the European Union to counteract the loss of biodiversity and related ecosystem services in agricultural landscapes. Although vegetation composition of the strips is essential for most fauna groups, comprehensive studies analysing vegetation development and influencing factors are rare.
2. From 2017 to 2019, we investigated the vegetation composition of 40 perennial wildflower strips (WFSs) implemented in 2015 or 2016, and 20 cereal fields without WFS across Saxony-Anhalt, Germany. We analysed environmental factors on plot (cover of grasses, shading, soil fertility) and four landscape-scale levels (habitat diversity, proportion of WFS and open habitats). The provision of nectar and pollen resources was estimated by the newly developed Pollinator Feeding Index (PFI). All strips had been implemented by farmers as AES with species- rich seed mixtures comprising 30 native forbs.
3. In all study years, forb species richness, cover and related nectar and pollen supply were much higher on WFSs than on controls, confirming the effectiveness of this AES. Although sown native forbs contributed the most to the high PFI values, spontaneously established forbs expanded the total range of species considerably, especially in winter and spring. While sown forb communities remained similar over time, spontaneous forbs showed a higher species turnover. Altogether, shading and grass cover had the greatest negative effect on the performance of the sown forbs. Landscape variables had only minor effects and were inconsistent in their importance across scale levels and years.
4. Synthesis and applications. Successfully established perennial wildflower strips (WFSs) sown with species-rich native seed mixtures provided a forb-rich and diverse vegetation throughout the AES funding period of 5 years. By supplying feeding resources for pollinators under various landscape situations, WFSs have significant potential to promote farmland biodiversity and related ecosyste services. We recommend the mandatory use of species-rich wildflower mixtures for perennial flower strips and to avoid their creation in heavily shaded field edges. Advisory services for farmers are necessary to prevent failures in WFS implementation and management and to improve their ecological effectiveness.
Green roofs are known to mitigate the negative effects of urban consolidation by offering diverse ecosystem functions compared to non-vegetated roofs. However, the support for native biodiversity might be improved by using native plant species. In a mesocosm experiment, we studied the suitability of three commercial green-roof growth substrates for the establishment of 27 native plant species from dry sandy grasslands of northwestern Germany over the course of four years. The substrates were mineral-based, but differed in the layering of organic matter. Total establishment rates reached 44–59% in Year 4, indicating the general suitability of the substrates. During the first weeks after seeding, with light irrigation, the vascular plant cover was greater in the similar substrates Zincolit® Plus (Z) and Zincolit® Plus-Leicht (ZL) with their compost-based organic mulch layers than in the substrate Sedumteppich (ST) with its organic matter evenly admixed with the mineral aggregates. In Years 2 and 3, however, the vascular plant cover was greater in the ST substrate, likely due to the better availability of water and nutrients from the organic matter compared to the dry surface-mulch layer variants Z and ZL. After severe drought events, the decline in plant cover was more pronounced in the ST substrate, likely representing a trade-off between lush growth and a susceptibility to drought. An indicator-species analysis revealed differences in species composition between the ST and Z/ZL substrates. Annual plant species were indicators of the ST substrate. Perennials, such as Thymus pulegioides and Achillea millefolium, were typical of the Z and ZL substrates. In addition to the general suitability of the tested standard substrates for target species establishment, the study indicated that a combination of different layers of substrate components resulted in different vegetation patterns that may have a positive effect on green-roof biodiversity.
Are natural floods accelerators for streambank vegetationdevelopment in floodplain restoration?
(2021)
Riverbanks are very dynamic habitats for riparian vegetation strongly influenced byfluvial and geomorphic processes. This habitat type was severely reduced in the pastby river straightening and bank stabilisation. Restoration and establishment of newfloodplain streams promote this habitat, but a directed succession to later stages wasobserved many times. Our study aimed to analyse whether the often observeddirected succession of the streambank vegetation after restoration implementationcould be reversed by a natural flood along a newly created floodplain stream. Weinvestigated the effects of a natural flood in 2013 and different prerestorationconditions on species development in the riparian zone. Vegetation was studiedalong 12 transects in four different sections from 2011 to 2014. Species composi-tion differed strongly between the sections. Species richness was lowest in a newlydug steep section with high morphological dynamics and highest on wider flatstreambanks. Changes during the years reflecting different hydrological eventsvaried between sections. The high natural flood in 2013 reduced the cover of theherb layer and increased bare ground, which led in most sections to a loss of non-target species. Total target species richness did not change due to the natural flood,while target species showed a high turnover rate. In the following year, however,the flood‐induced development of species composition, in general, was reversed.Natural floods changed abiotic and biotic conditions along the streambank, but theydid not accelerate ecological restoration towards predefined target ecosystems.However, they were necessary to preserve the needed dynamic vegetation changesand species turnover to hinder the succession to later stages dominated by a fewspecies. Our study shows that riparian vegetation near the streambank can bemonitored most effectively in cross‐profile transects, both in the long‐term andevent‐related.
Establishment of calcareous grassland on ex-arable fields by introducing target species is one of the most frequently used methods to restore the species assemblages of this highly endangered habitat type. The present study evaluates the long-term success of calcareous grassland restoration on former arable land in the vicinity of one of the oldest nature reserves in Bavaria, the “Garchinger Heide”. The restoration experiment combined different measures like topsoil removal, transfer of freshly cut seed-containing hay and additional sowing to the following variants in a 21-year experiment: (1) No topsoil removal, no hay transfer (control), (2) no topsoil removal with immediate hay transfer, (3) topsoil removal with immediate hay transfer and (4) topsoil removal with hay transfer 10 years after the start of restoration. Eleven Red List species which had not been transferred successfully were additionally sown after 9 to 19 years. Due to a limited availability of seeds, sowing of these species was mainly restricted to areas with topsoil removal, where better establishment was expected due to low vegetation cover. Five rare species with abundant seed production were also sown to plots without topsoil removal and hay transfer. The nature reserve served both as the donor area of the target species and as the reference to evaluate restoration success. Regarding aboveground biomass and total vegetation cover, greatest similarity to the donor site was observed on plots without topsoil removal. In contrast, the highest numbers of target species occurred on plots with topsoil removal, hay transfer and additional sowing. Similarity in species composition between restoration sites and the reference area increased over time, but species composition of restored sites did not fully reflect the reference after 21 years. One reason for the remaining dissimilarity was probably that topsoil removal favored stress tolerant species which were less common on the mature and more fine-grained soils of the nature reserve. Plots without topsoil removal still differed from the reference by their high vegetation cover and a significantly higher proportion of mesophytic grassland species. The study also showed that 19 Red List species were successfully established on the former arable fields, eight of them presumably by sowing. Nevertheless, various other rare species have not been observed yet. Results on functional traits characterizing environmental adaptation and reproduction also underlined the differences between restoration plots and the reference site. Our study presents a ʽdynamic restoration approachʼ where managers evaluated the original factorial treatments after a decade and modified them by additional treatments where development was sub-optimal. Such additional treatments may have confounded the experimental design, but from a management perspective proved to be a promising option to establish species rich grassland of high conservation value with a reasonable expenditure of time.
Within the frame of the EU Common Agricultural Policy, most countries subsidise the establishment and maintenance of perennial flower strips on arable land within Agri-Environmental Schemes to provide foraging habitats and refuges for wildlife.
In a replicated field experiment, we studied the effects of different types of seed mixtures on the establishment and maintenance of perennial flower strips on fertile arable land in the federal state of Saxony-Anhalt, Germany over seven years. The seed mixtures were commonly applied within recent Common Agricultural Policy funding periods: (1) a low-diversity cultivar standard seed mixture (CULTIVAR), (2) a high-diversity cultivar and native plant mixture (MIX), and (3) a high-diversity native plant mixture (WILDFLOWER). All plots were mulched every year in March and at the beginning of August.
The low success of CULTIVAR triggered the massive encroachment of spontaneously established perennial grasses. In MIX, too, cultivars have disappeared after the first year. Both wildflower variants were successful in maintaining a high cover of sown perennial native forbs and a high ratio of established sown species, even after seven years. WILDFLOWER always tended to show better values than MIX. Furthermore, spontaneously establishing species began to spread their cover in MIX in the fifth year, with a very strongly increasing tendency, whereas in WILDFLOWER cover of spontaneously immigrating species stayed satisfyingly low.
Using native wildflowers to establish perennial wildflower strips was very effective in maintaining high species diversity within the Agri-Environmental Schemes funding period of five years and beyond. WILDFLOWER was especially successful. On the other hand, CULTIVAR failed completely. On fertile soils in regions with rather low yearly precipitation, mulching twice a year supported the maintenance of perennial wildflower strips.
Extensive green roofs (EGRs) offer several beneficial ecosystem services for sustainable urban development. However, most standard green roofs have been designed with species-poor plant mixtures containing non-native species. Aiming to increase the nature conservation values of EGRs, we developed and tested a vascular plant seed mixture including regionally occurring native sandy dry grassland species in experimental miniature roofs in Northwestern Germany (temperate oceanic climate) over 4 years. We tested the mixture at two seed densities (1 and 2 g/m2). Additionally, we tested seeding at 1 g/m2 and introducing raked plant material collected from an ancient dry grassland. The total establishment rates of sown species reached 92–96% in the first year, but dropped to 40–60% in the last 2 years, with the highest values for the plots with raked material. Twenty-four additional species (11 vascular, 7 lichen, and 6 moss species, including 7 red-list species) typical of sandy dry grasslands were introduced through the raked material. Vascular plants reached 60–70% cover in the second year. Severe drought periods in the third and the fourth year led to a strong decline of vascular plant cover then. As this cover was higher in the plots with raked material, we assume facilitative effects through the well-developed cryptogam layer containing a mix of pleurocarpous and acrocarpous mosses and lichens. Spontaneously establishing acrocarpous mosses in sown plots did not seem to provide this same function. We conclude that EGRs designed with regionally occurring sandy dry grassland plant species and especially the application of raked plant material from ancient grassland is a fruitful approach to increase the value of green roofs for native phytodiversity.
Diet can influence healthy aging through anti- or proinflammatory effects, partly by modulating the gut microbiome composition. This study investigated the relationships between the Dietary Inflammatory Index (DII), the gut microbiome, and nutritional status in elderly individuals. Methods: This cross-sectional analysis included 114 home-dwelling individuals aged over 70 years. The Energy-adjusted DII (E-DII) was calculated from 3-day food diaries, and blood samples were taken to measure micronutrient status, glucose, and lipid metabolism. Body composition was assessed using bioimpedance, and fecal gut microbiome composition was analyzed through 16S rRNA gene sequencing. The participants were categorized into maintaining an anti-inflammatory diet (AD) and a pro-inflammatory diet (PD) based on the median E-DII score. The associations of E-DII groups with blood markers and microbial diversity and composition were examined using the analysis of covariance, permutational analysis of variance, and multivariate linear models. Results: The AD (n = 57, 76 ± 3.83 years) and PD (n = 57, 75 ± 5.21 years) groups were similar in age but differed in sex distribution, with a higher proportion of females in the AD group (p = 0.02). When compared to the PD group and adjusted for sex, the AD group had a lower body mass index, fat mass, fasting insulin level, HOMA-IR (Homeostasis Model Assessment of Insulin Resistance), fasting triglycerides, and serum uric acid concentration (all p < 0.05), with higher concentrations of high-density lipoprotein, red-blood-cell folate (RBC), and Omega-3 index (all p < 0.05). While the microbial diversity and composition did not differ between the DII groups, folate concentrations were negatively associated with Agathobacter and positively associated with Bacteroides abundance (both q = 0.23). Lower uric acid concentrations were associated with a higher abundance of Bifidobacterium (q = 0.09) and lower abundance of Phocaeicola (q = 0.11). Discussion: The study suggests that following an anti-inflammatory diet is associated with improved nutritional status in the elderly. Dietary blood markers, rather than E-DII, were found to be associated with the gut microbiome, suggesting a potential link between the microbiome and changes in nutritional markers independent of diet. Further studies are needed to explore the causal relationship between dietary inflammatory potential, gut microbiome, and healthy aging.
Advances in high-throughput DNA sequencing have propelled research into the human microbiome and its link to metabolic health. We explore microbiome analysis methods, specifically emphasizing metabolomics, how dietary choices impact the production of microbial metabolites, providing an overview of studies examining the connection between enterotypes and diet, and thus, improvement of personalized dietary recommendations. Acetate, propionate, and butyrate constitute more than 95% of the collective pool of short-chain fatty acids. Conflicting data on acetate’s effects may result from its dynamic signaling, which can vary depending on physiological conditions and metabolic phenotypes. Human studies suggest that propionate has overall anti-obesity effects due to its well-documented chemistry, cellular signaling mechanisms, and various clinical benefits. Butyrate, similar to propionate, has the ability to reduce obesity by stimulating the release of appetite-suppressing hormones and promoting the synthesis of leptin. Tryptophan affects systemic hormone secretion, with indole stimulating the release of GLP-1, which impacts insulin secretion, appetite suppression, and gastric emptying. Bile acids, synthesized from cholesterol in the liver and subsequently modified by gut bacteria, play an essential role in the digestion and absorption of dietary fats and fat-soluble vitamins, but they also interact directly with intestinal microbiota and their metabolites. One study using statistical methods identified primarily two groupings of enterotypes Bacteroides and Ruminococcus. The Prevotella-dominated enterotype, P-type, in humans correlates with vegetarians, high-fiber and carbohydrate-rich diets, and traditional diets. Conversely, individuals who consume diets rich in animal fats and proteins, typical in Western-style diets, often exhibit the Bacteroides-dominated, B-type, enterotype. The P-type showcases efficient hydrolytic enzymes for plant fiber degradation but has limited lipid and protein fermentation capacity. Conversely, the B-type features specialized enzymes tailored for the degradation of animal-derived carbohydrates and proteins, showcasing an enhanced saccharolytic and proteolytic potential. Generally, models excel at predictions but often struggle to fully elucidate why certain substances yield varied responses. These studies provide valuable insights into the potential for personalized dietary recommendations based on enterotypes
The Internet of Things (IoT) is the enabler for new innovations in several domains. It allows the connection of digital services with physical entities in the real world. These entities are devices of different categories and sizes range from large machinery to tiny sensors. In the latter case, devices are typically characterized by limited resources in terms of computational power, available memory and sometimes limited power supply. As a consequence, the use of security algorithms requires of them to work within the limited resources. This means to find a suitable implementation and configuration for a security algorithm, that performs properly on the device, which may become a challenging task. On the other side, there is the desire to protect valuable assets as strong as possible. Usually, security goals are recorded in security policies, but they do not consider resource availability on the involved device and its power consumption while executing security algorithms. This paper presents an IoT security configuration tool that helps the designer of an IoT environment to experiment with the trade-off between maximizing security and extending the lifetime of a resource constrained IoT device. The tool is controlled with high-level description of security goals in the form of policies. It allows the designer to validate various (security) configurations for a single IoT device up to a large sensor network.
Reconnection of floodplains to rivers to enhance fluvial dynamics is a favored method of floodplain restoration in Europe. It is believed that the restoration of hydrological conditions of the floodplain facilitates natural dispersal of target species, and hence the reestablishment, of typical plant communities. The aim of our study was to investigate whether floodplain target species could reach restoration sites via hydrochorous dispersal. We analyzed seed inflow from the river and seed dispersal in different sectors of a new watercourse in the Danube floodplain. Seeds were captured using 27 seed traps during three sampling periods of 3 weeks each from summer 2011 to spring 2012. After germination seedlings were identified, we detected a total of almost 39,000 seeds of 176 species, including 80 target species of riparian habitats. We found significant differences between seasons (most seeds in autumn/winter) and between stream sectors. Fewer seeds came in from the Danube (2,800 seeds) than were transported within the floodplain. Several new floodplain target species were detected, which had not been found in the aboveground vegetation or soil seed bank before the start of the restoration. Seeds of nonnative species did not disperse further than approximately 1 km. Our results indicated that hydrochorous seed dispersal from upstream habitats along the new watercourse was important for the establishment of target species and hence for the success of floodplain restoration. Technical water diversion weirs must be traversable for seeds, and small donor sectors upstream might enhance the reestablishment of target vegetation along new sectors downstream.
In urban areas, open space including brownfields often became rare due to increasing urbanisation. Urban brownfields can be important for biodiversity, but especially brownfields in early successional stages seem to be refused by urban residents due to their sparse vegetation and less aesthetic appearance. The aim of this study was to revegetate a young demolition site in the city core of Osnabrück, Germany and thereby to support native plant diversity and aesthetic values. We developed two seed mixtures of native plant species and tested them in a large-scale field experiment over two growing seasons.
Both seed mixtures developed towards structurally diverse and flower-rich vegetation. Establishment rates of sown species were consistently larger than 75%. Revegetation of the predominantly bare anthropogenically transformed soil by introduced species occurred fast. Vascular plant cover and vegetation height were higher on sown plots than in controls, but did not differ between the seed mixtures. Seeding did not increase plant species richness and did not reduce the establishment of a potentially invasive non-native plant species. The cover of Red-List species from the spontaneous vegetation was significantly higher in control plots. Our results indicate that not all aims can be reached on one restoration site. It has to be discussed if it is better to invest a restoration budget for measures aiming to increase acceptance of endangered pioneer plant species from the spontaneous vegetation or to introduce more attractive and more competitive species of later successional stages.
Species dispersal, establishment, and assembly are crucial stages of the life history of plants, and clear understanding ofthe governing forces and rules that shape species composition in a particular community is vital for successful ecologicalrestoration. In this article, we focus on five aspects of seed dispersal and plant establishment, which should be consideredduring habitat restoration actions. In the first two sections, we discuss the success of spontaneous dispersal and establishmenton restoration based on either spatial dispersal or local seed banks. In the third section, we assess the possibilities ofspecies introduction and assisted dispersal. In the fourth section, we introduce some possibilities for the improvement ofestablishment success of spontaneously dispersed or introduced species. Finally, we highlight issues influencing long-termpersistence and sustainability of restored habitats, related to the alteration of management type and intensity, climate change,and spread of non-native species. With the present article, we introduce the special issue entitled “Seed dispersal and soil seedbanks – promising sources for ecological restoration” containing 15 papers by 62 authors from 10 countries arranged in theabovementioned five topics.
Soil seed banks have a high potential for vegetation re-establishment in restoration projects. We studied the soil seed bank in an oxbow system of a disconnected floodplain of the Danube River in Southern Germany. The aim of the study was to analyze if floodplain target species were still present in the seed bank after more than 150 years of embankment and disconnection from fluvial dynamics. In this context we investigated seed density, seed bank species richness and species composition in four broad habitat types with and without water-level fluctuations during the time of embankment (permanent water, fluctuating water, reed bed, hardwood floodplain forest). In addition, the similarity between seed bank and above-ground vegetation in these habitat types was studied in order to predict the success of future restoration measures. In total, 124 vascular plant species were determined in the seed bank samples. More than 50 % (66 species) were target species typical for floodplain habitats and 26 of these target species were lost or very rare in the above-ground vegetation. The four habitat types differed significantly in mean seed density and mean species richness. Mean species richness and the number of target species in the seed bank as well as the mean seed density were greatest in the habitats with fluctuating water level whereas mean seed density was much lower in the parts with more or less stable conditions like permanently standing water and hardwood floodplain forest. Sørensen similarity between seed bank and above-ground vegetation was very low in habitats with more or less stable water levels and desirable floodplain target species were very rare or completely absent. Our results indicate that the soil seed bank can be an important seed reservoir for the ecological restoration of floodplain plant communities especially for habitats with unstable environmental conditions during the period of disconnection. Restoration of water level dynamics is important to maintain the seed bank of populations of floodplain target species.
The break-up of the Soviet Union in 1991 triggered cropland abandonment on a continental scale, which in turn ledto carbon accumulation on abandoned land across Eurasia. Previous studies have estimated carbon accumulationrates across Russia based on large-scale modelling. Studies that assess carbon sequestration on abandoned land basedon robust field sampling are rare. We investigated soil organic carbon (SOC) stocks using a randomized samplingdesign along a climatic gradient from forest steppe to Sub-Taiga in Western Siberia (Tyumen Province). In total, SOCcontents were sampled on 470 plots across different soil and land-use types. The effect of land use on changes in SOCstock was evaluated, and carbon sequestration rates were calculated for different age stages of abandoned cropland.While land-use type had an effect on carbon accumulation in the topsoil (0–5 cm), no independent land-use effectswere found for deeper SOC stocks. Topsoil carbon stocks of grasslands and forests were significantly higher thanthose of soils managed for crops and under abandoned cropland. SOC increased significantly with time sinceabandonment. The average carbon sequestration rate for soils of abandoned cropland was 0.66 Mg C ha1yr1(1–20 years old, 0–5 cm soil depth), which is at the lower end of published estimates for Russia and Siberia. Therewas a tendency towards SOC saturation on abandoned land as sequestration rates were much higher for recentlyabandoned (1–10 years old, 1.04 Mg C ha1yr1) compared to earlier abandoned crop fields (11–20 years old,0.26 Mg C ha1yr1). Our study confirms the global significance of abandoned cropland in Russia for carbonsequestration. Our findings also suggest that robust regional surveys based on a large number of samples advancemodel-based continent-wide SOC prediction.
German farmers are required by law to regularly self-assess the welfare of their animals. The project Q Check is aiming at developing a system that will assist farmers to objectively assess animal health and welfare in dairy cows. For this reason, a quarterly report will be compiled from animal-based key indicators to give an overview of the on-farm situation. The anonymised and aggregated reports can also be used for national animal welfare monitoring: Continuous collection of these key indicators enables the summary and publication of figures reflecting the current animal health and welfare status and progressions at federal state and at national level. Q Check is based on four data recording and analysis systems, which are already established in Germany and implemented on a national level. Out of these systems, the most suitable indicators to describe herd health have been selected by 215 experts within a twostage Delphi study. In addition, over 50 face-to-face interviews with stakeholders related to the German dairy sector have been performed in order to take into account the socio-scientific point of view. To complete the process, the selected indicators are currently being checked against mass data and hence tested for suitability regarding monitoring purposes. An automatic farm-specific evaluation of animal health, based on verified indicators, will provide support to farmers in fulfilling their legal requirements and in identifying weak points on the individual farms. A benchmarking system will be set up which will allow tracking the individual herd health indicators in the same farm in their course over time and compared with similar farms. These routinely provided horizontal and vertical statistics will facilitate targeted intervention and support objectified management decisions, implying that dairy farmers can benefit in several respects. In the course of the project, new tools for determining the risk of ketosis in the scope of milk recording will also be validated and implemented at national level to enhance monitoring of this major disease complex. The results of these nationwide, systematic investigations will contribute substantially to objectifying the discussion about the health and welfare situation of dairy cows.
Dairy farming has been the subject of public debate on animal welfare for a number of years now. Animal welfare discussions on dairy farming often include the demand for more nature connectedness in this area. This study focuses on the divergent perspectives of consumers and scientists on the importance of more nature connectedness for animal welfare strategies in German dairy farming. Within Europe, Germany is the main producer of cow’s milk and an important industry in many rural areas in Germany is dairy farming. The insights presented are based on qualitative interviews with dairy farming and livestock researchers from Germany and Austria. A key finding of this study is that we need to look more closely at the actual content of nature claims in animal welfare debates. The scientists interviewed tend to see idealized conditions in animal welfare discussions with images of nature which in fact seldom lead to improved conditions in dairy farming and, even then, only to a limited extent. The scientists interviewed rate calls for more nature connectedness in dairy farming from the nonagricultural public as anti-modern, complexity-reducing, and normative. Nevertheless, some of the scientists interviewed did have valuable insights into the nonagricultural public’s criticism of dairy farming practices. These scientists argued, however, that animal welfare needs to differentiate between nature connectedness and the innate needs of cattle when it comes to animal welfare strategies. An important conclusion of the study is that more discussion formats are needed to promote the exchange of ideas between different social groups attempting to understand animal welfare in dairy farming.
Restoring depleted soil organic carbon (SOC) stocks of arable land to remove carbon from the atmosphere and offset fossil fuel emissions is a promising strategy for the mitigation of climate change. In agroecosystems conservational tillage practices and the abandonment of formerly plowed fields (ex-arable land) are shown to have the highest potential to sequester SOC. Nevertheless reported sequestration rates vary and the effects of environmental site conditions remain poorly understood. Our results are based on a meta-analysis of 273 paired SOC estimates from 65 publications which included only mineral soils from the temperate zone. SOC stocks of ex-arable grasslands with an average of 14 years since abandonment were 18% larger compared to the SOC of arable land. Likewise, SOC stocks of never-plowed grassland plots were 11% larger than the SOC stocks of abandoned fields. The average sequestration rate was 0.72 t C ha− 1 yr− 1. Semi-arid and sub-humid climate as well as low initial SOC stocks positively affected proportional SOC gains suggesting that the recovery of carbon stocks is not limited by low primary production. Therefore, the northward shift of cultivation areas in the temperate zone will lead to the abandonment of soils with high SOC recovery potential. However, if native soils are opened up elsewhere to compensate for yield losses due to abandonment the surplus of SOC in ex-arable land can easily be overcompensated by cultivation losses.
Despite the high significance of the Western Siberian grain belt for crop production in Russia, its weed communities are largely unknown. In this region spring wheat is grown on fertile Chernozem soils with large field sizes but land-use intensity per area is low compared to Central Europe. By usin a randomized sampling design we studied arable weed assemblages in the northern forest-steppe zone of Tyumen region on 99 within-field sampling plots of 100 m² size. Surprisingly, with average of 9.8 ± 3.8 species 100 m-2 species richness was low when compared with low-input farming in Central Europe and did not differ between areas of different land-use intensity. Against expectations species composition was not predominantly controlled by soil characteristics and climate, most likely due to short natural gradients. Instead, management factors such as fertilization and tillage intensity seemed to be important factors. Except for two species the Tyumen weed flora consisted mainly of species that are widespread throughout the temperate zone. We found only 10 species with an origin or core area in North Asia or Eastern Europe. The species pool was generally small and with 26% the proportion of non-native spe cies (archaeophytes) was low, when compared to Central European weed communities. Given that weed communities with higher species richness are described from neighboring Bashkiria, we conclude that arable land-use intensity in Tyumen region is high enough to reduce community species richness within arable fields estimated by a randomized sampling design. Since measured soil nutrient values did not affect species richness, herbicide use is most likely the crucial management factor. Furthermore, species-richness was vitally restricted by the small species pool. The low proportion of thermophilous arable weed species that originate from the Mediterranean or Middle-Eastern area and contribute signif icantly to the Central European weed diversity indicate that climatic dispersal limitations may be re sponsible for the small number of weed species in the Tyumen flora. An additional constraint was the short history of arable farming in Western Siberia, where considerable arable land use was started only by the end of the 17th century.
Between Ekaterinburg and Nowosibirsk, in the Western Siberian grain belt, spring wheat is grown on fertileChernozem soils. Field and farm sizes are large but the land-use intensity per area is low compared to CentralEurope. Fertilizers and pesticides are applied only in low to moderate quantities and yields range between 10and 20 dt ha-1 . We studied the arable weed flora in the northern forest steppe zone of Tyumen region using arandomized sampling design. Surprisingly, the species richness was only moderate, on average 9.8 ± 3.8species per 100 m². Compared to weed communities of Bashkiria (Southern Ural) and less intensively usedarable land of Central Europe these numbers are rather low. Moreover, most of the recorded species werecosmopolitans or widely distributed throughout the temperate zone. We suggest that the land use intensitywas high enough to reduce the density of a number of weed species in a way that they were not registered byour random sampling design. The limited conservational value of the weed vegetation of large grain fields inTyumen leads to the conclusion that if intensification of land use is unavoidable, it should be directed to arableland and not to ex-arable land or ancient grassland, which is of higher conservation value.
Following the collapse of the Soviet Union in 1991 around 45 million hectares
of arable land became abandoned across Russia. Our study focused on the recovery
potential and conservation value of grassland vegetation on ex-arable land in the Tyumen
region of the Western Siberian grain belt. We compared ex-arable grasslands of different
successional stages with ancient grasslands as reference for the final stage of succession
along a climatic gradient from the pre-taiga to the forest steppe zone. Plant community
composition and species richness of ex-arable land clearly developed towards reference
sites over time, but even after 24 years of abandonment, the grassland vegetation had not
totally recovered. The c-diversity of vascular plants was slightly higher on ex-arable land
than in ancient grasslands but the mean a-diversity was still moderately lower. A significant proportion of the vegetation of ex-arable land still consisted of ruderal and mesic
grassland species and the number and cover of meadow-steppe species was significantly
lower than in ancient grasslands. Grazing and time since abandonment positively affected
the reestablishment of target grassland species, whereas it was negatively affected by the
cover of grasses. In contrast to ex-arable land, the conservation value of arable land is only
modest. Therefore, future intensification of land use is most likely less harmful if directed
to existing arable land. Re-cultivation of ex-arable land and grassland improvement operations such as seeding of competitive grass species are major threats for the biodiversity of secondary grasslands on ex-arable land in the forest steppe zone of Western Siberia.
Ecological restoration of an urban demolition site through introduction of native forb species
(2020)
Urban brownfields can provide habitats for endangered native plant species but may also support invasive non native species. The aim of our study was to develop and test different measures for the ecological restoration of an urban brownfield. We aimed to enhance native plant species richness by seeding two native forb seed mix tures containing 25 (HD-mixture) and 13 species (LD-mixture), respectively, without affecting spontaneously colonizing plant species of nature conservation value. Additionally, we tested the effects of species introduction and mowing on the establishment of invasive non-native plant species, woody species development, and per ennial grass dominance.
With establishment rates of 84% (HD) and 92% (LD) in the first study year and about 60% for both seed mixtures in the fourth year, species introduction was successful and led to rapid re-vegetation of the formerly bare brownfield. Although seeding did not result in increased species richness using either seed mixture, the dominance of perennial grasses was significantly reduced by the establishment of forb species from the HD mixture. Overall, we observed the spontaneous establishment of ten plant species of conservation value; seeding affected these species only temporarily, in the second year. Seeding (with either seed mixture) and mowing both resulted in reduced cover of woody species and a lower frequency of the invasive non-native Robinia pseudoa cacia.
Our study demonstrated the high nature conservation value of dry and nutrient-poor urban brownfields for spontaneously occurring threatened plant species. Further studies have to evaluate if the reduced cover of grasses and woody species through introduction of site-specific native forb species might increase these sites’ aesthetic value and broader acceptance of brownfields by urban residents.