Grassland Conservation Research Articles

Structural Characteristics and Driving Factors of Rhizosphere Microbial Communities in the Rhizosphere of Six Stipa Species Across the Ningxia Steppe

The relation and interaction of rhizosphere microbial communities with local environmental factors and root traits is currently a vibrant research hotspot. Yet little is known about how the morphological and functional properties of roots in steppe plants affect microbial community structure. Hence, this study investigated the rhizosphere soil of six Stipa species across the Ningxia steppe in China to examine how the composition of their microbial communities responds to both root traits as well as surrounding environmental factors. Our results reveal significant differences (p < 0.001) in the composition of rhizosphere microbial communities among different Stipa species. The dominant bacterial and fungal phyla are Proteobacteria and Ascomycota, respectively; further, Mortierellomycota plays a key role in the fungal community and is closely associated with other fungal taxa. According to the functional gene predictions for bacteria and fungi, the rhizosphere microbes associated with Stipa species are mainly related to organic matter metabolism and nitrogen cycling. We find that soil physicochemical properties (SOC, TN, TP, AP, SWC, FL, SL) and root traits (RTD, Rtn) are pivotal factors which directly influence the structure of microbial communities dwelling in the rhizosphere of Stipa species. The dominant phyla of fungi and bacteria can respond to those properties in two contrasting ways. One group, consisting of bacteria such as Acidobacteria and fungi like Mortierellomycota, has a relative abundance that is positively correlated with soil nutrients (SOC, TN, AN, TP), whereas the second group, which includes bacteria such as Bacteroidetes and fungi like Ascomycota, is characterized by a negative correlation. More importantly, our results show that root traits significantly impact (p < 0.001) fungal diversity, whereby the morphological and functional properties indirectly affect the composition of bacterial and fungal communities by modulating soil properties. Altogether, the findings suggest that the morphological and functional properties of Stipa roots play a prominent role in shaping the community structure of rhizosphere microbes in steppe, providing a theoretical basis for exploring changes in these communities across space and time, as well as offering insights for grassland conservation and sustainable management.

Landscape diversity, habitat connectivity, age and size determine the conservation value of limestone quarries for diverse wild bee communities

Abstract Abandoned and even active limestone quarries (excavation sites) can represent important secondary habitats for many species, including wild bees, associated with dry grasslands, which are threatened biodiversity hotspots in Europe. However, is not well understood how interactions between local habitat and landscape characteristics influence the value of limestone quarries for wild bees and how this could guide conservation schemes. We studied how wild bee communities in limestone quarries are affected by landscape variables (connectivity to neighbouring dry grasslands, landscape diversity), local quarry characteristics (area, age, woody vegetation cover, flowering plant species) and their interactions. We surveyed bee communities during 208 transects in 19 quarries in southern Lower Saxony, Germany. In total, we recorded 114 bee species (2360 individuals), including 35 endangered species. High flowering plant species richness positively affected bee abundance and richness. Large quarry area was important for determining the presence of endangered bee species. High levels of woody vegetation cover had a negative effect on bee abundance and richness. Bee abundance and richness can increase with quarry age, but only at sites with moderate woody vegetation cover. We found potentially positive interactions between quarry age and landscape diversity and/or habitat connectivity to neighbouring dry grasslands. In particular, high habitat connectivity ensured stable richness of endangered species in old quarries. Synthesis and applications. Observed negative effects of high woody vegetation cover on bee communities highlight the importance of local management to reduce shrub encroachment and reset successional processes in limestone quarries. Local management is particularly important in old quarries of great ecological value, where the adverse impact of high woody vegetation cover on wild bees appears to be most severe. Large and old quarries with high connectivity to neighbouring dry grasslands are especially valuable for endangered bee species. Therefore, landscape‐scale restoration and conservation of dry grasslands is the most promising approach to promote endangered bee species through enhanced habitat connectivity.

Unveiling and advancing grassland degradation research using a BERTopic modelling approach

Grassland degradation presents overwhelming challenges to biodiversity, ecosystem services, and the socio-economic sustainability of dependent communities. However, a comprehensive synthesis of global knowledge on the frontiers and key areas of grassland degradation research has <pg=>not been achieved due to the limitations of traditional scientometrics methods. The present synthesis of information employed BERTopic, an advanced natural language processing tool, to analyze the extensive ecological literature on grassland degradation. We compiled a dataset of 4,504 publications from the Web of Science core collection database and used it to evaluate the geographic distribution and temporal evolution of different grassland types and available knowledge on the subject. Our analysis identified key topics in the global grassland degradation research domain, including the effects of grassland degradation on ecosystem functions, grassland ecological restoration and biodiversity conservation, erosion processes and hydrological models in grasslands, and others. The BERTopic analysis significantly outperforms traditional methods in identifying complex and evolving topics in large datasets of literature. Compared to traditional scientometrics analysis, BERTopic provides a more comprehensive perspective on the research areas, revealing not only popular topics but also emerging research areas that traditional methods may overlook, although scientometrics offers more specificity and detail. Therefore, we argue for the simultaneous use of both approaches to achieve more systematic and comprehensive assessments of specific research areas. This study represents an emerging application of BERTopic algorithms in ecological research, particularly in the critical research focused on global grassland degradation. It also highlights the need for integrating advanced computational methods in ecological research in this era of data explosion. Tools like the BERTopic algorithm are essential for enhancing our understanding of complex environmental problems, and it marks an important stride towards more sophisticated, data-driven analysis in ecology.

Herders’ willingness to accept for grassland grazing ban in northwest China

Payment for Ecosystem Services (PES) has been widely acknowledged as an effective tool for mitigating grassland degradation and enhancing ecosystem services provision. However, critical factors such as herders’ willingness to accept (WTA) preferences and their compensation expectations, are often overlooked, leading to insufficient effectiveness of PES initiatives. This study focused on grassland ecological compensation policy (GECP), quantifying herders’ WTA compensation for grassland grazing bans. Through face-to-face surveys and employing the contingent valuation method, we estimated households’ WTA for participating in a grassland conservation program aimed at bolstering ecosystem service provision. Our findings indicate that herders required an average compensation of 237 CNY mu-1 yr-1 to engage in the grazing ban program. Notably, our study revealed that herders’ environmental awareness positively influenced their willingness to participation, whereas larger family sizes were negatively correlated with WTA. Additionally, herders in better health, with higher livestock incomes or categorized as semi-herders, tended to accept lower compensation levels. These insights are crucial for improving the effectiveness of GECP and provide valuable reference points for similar analyses in economically disadvantaged and ecologically fragile regions.

Moderate grazing intensity and pika disturbance can enhance plant diversity and soil nutrient cycling in the alpine grasslands of the Qinghai-Xizang Plateau

Grazing livestock and pikas, as the primary herbivores in grasslands, influence the health of grassland ecosystems through activities such as feeding, burrowing, and trampling. This study reviews 86 articles and examines the effects of varying grazing levels and pika activity on alpine grassland vegetation and soil in the Qinghai-Xizang Plateau, providing scientific insights to guide grassland conservation efforts. The research shows that: 1) Both grazing and pika disturbance significantly reduce aboveground biomass (AGB) in alpine grasslands (p < 0.05). Moderate grazing increases diversity indices, while pika disturbance has the opposite effect. 2) As grazing intensity increases, there is a significant decrease in total nitrogen (TN), total phosphorus (TP), and soil organic matter (SOM) content (p < 0.05). However, moderate pika disturbance leads to a significant increase in TP and TN content (p < 0.05). 3) In grazing trials, bulk density (BD) and the Shannon-Wiener index are significant positive drivers. Conversely, during pika disturbance, the Shannon-Wiener index and total nitrogen (TN) act as significant positive drivers, while BD is a significant negative driver. The study's findings indicate that moderate grazing intensity and pika disturbance can enhance plant diversity indices in grasslands, as well as improve soil structure and nutrient levels. Therefore, establishing a reasonable grazing system and controlling the pika population are effective methods for managing alpine grasslands.

Grassland albedo as a nature-based climate prospect: the role of growth form and grazing

Abstract Nature-based solutions for mitigating climate change focus largely on land management to reduce carbon emissions and enhance carbon sequestration. Tree planting, commonly advocated for carbon offset, threatens grassland biodiversity and may induce positive radiative forcing (warming) by lowering albedo. Before making decisions about land-use changes in grasslands, an understanding of the fine-scale albedo of grassy versus woody vegetation is needed. Existing satellite-based albedo products offer global coverage with temporally fine, but spatially coarse, resolution, whereas fine-scale in situ grassland albedo data are sparse. We examined the hypotheses that albedo varies seasonally between grass type patches, between shrub and grass patches, and with grazing at the patch scale. Using a tripod-mounted albedometer, we quantified albedo of seven distinct grassland patches in South Africa’s eastern Karoo during early and late dormancy and growing seasons. Patches included intensely-grazed grazing lawn (Cynodon dactylon), grazed and less-grazed red tussock grass (Themeda triandra), grazed and less-grazed white tussock grass (Eragrostis lehmanniana), shrub (Pentzia incana) encroached grass, and bare ground. Season influenced albedo in all patches and, additionally, we found strong differences for the same period between years due to varying rainfall and temperature patterns. For grass-dominated patches, albedo differences were most pronounced during early dormancy, likely due to an effect of grass inflorescences. Albedo of intensely-grazed grazing lawns was consistently higher than other patches, except during early dormancy when white tussock grass albedo was equally high. We found no albedo difference between grazed and less-grazed tussock patches of either red or white grass. Shrub-encroached patches exhibited consistently lower albedo than other patches. Our findings underscore the nuanced relationship between grassland patches and albedo, with shrub encroachment, proposed afforestation, and certain grasses possibly increasing warming potential through reduced albedo. As climate initiatives extend into grasslands, understanding these patterns is essential for climate change mitigation and grassland conservation.

Population genomics of a specialized insect, Tetraopes texanus (Coleoptera: Cerambycidae), across a fragmented grassland system

AbstractSpecialist insects are especially susceptible to loss of genetic diversity in the face of habitat destruction and fragmentation. Implementing effective conservation practices for specialist insects will benefit from knowledge of population structure and genetic diversity. Because insects are hyper-diverse, characterizing the population structure of all species within the insect community is untenable, even if focused within a particular habitat type. Thus, concentrating on a single species specialized to a particular habitat type is needed to infer general trends. Here, we investigate the range-wide population genetics of Tetraopes texanus Horn 1878 (Coleoptera: Cerambycidae), which provides a useful model of grassland insects due to its’ habitat specificity and unique biology. Tetraopes texanus occurs primarily in Texas and Oklahoma, into Northern Mexico, and possibly into eastern New Mexico but also occurs in Black Belt prairies of Mississippi and Alabama. Mitochondrial and nuclear DNA (RAD-seq) analysis identified two distinct population clusters of T. texanus corresponding to the Texas and Oklahoma population and the Mississippi and Alabama population. Demographic models indicate ongoing, though incomplete, isolation of the two populations, with estimated dates of divergence in the mid-Pleistocene, coinciding with the end of a glacial period and a shift in glacial interval. These results can inform conservation of grassland adapted insects and offers insight to the biogeography of the Gulf Coastal Plain.

Livestock grazing strengthens the effect of vole activity on the soil microbial community

Livestock grazing may affect small mammalian herbivore-soil microbe interactions and their association with the structure and functions of the ecosystem. However, the role of factors such as vegetation and soil nutrients in regulating these impacts is not clear. Here we conducted a 9-year experiment in temperate steppe to study how Brandt’s vole (Lasiopodomys brandtii) affects the soil microbial community under different livestock grazing intensities. This experiment contained 12 field enclosures with three livestock grazing intensities: control (CK), light grazing (LG), and moderate grazing (MG). We found that vole activity does not significantly change soil microbial diversity under non-grazing conditions. However, under livestock grazing conditions, vole activity led to a significant reduction in soil bacterial diversity and an increase in fungal diversity, demonstrating the impacts of livestock grazing on rodents-soil microbe interactions. The activity of voles significantly altered soil bacterial community composition, with changes primarily attributed to variations in the relative abundance of the phyla Actinobacteria, Bacteroidetes, Firmicutes, Gemmatimonadetes, and Proteobacteria. The soil fungal community remained relatively stable despite vole activity, which can be attributed to the richness of fungal colonies in mycelium and their low sensitivity to changes in external conditions. Vole activity also influenced soil microbial functional groups, and the variations in these groups were further amplified by livestock grazing. Furthermore, the shift in the microbial community composition and diversity induced by vole activity were mainly associated with the reduction of plant aboveground biomass. Overall, our study suggested that livestock grazing enhanced the changes in the soil microbial community induced by rodents, underscoring the importance of managing livestock grazing regimes for grassland conservation.

Combining private and common property management: The impact of a hybrid ownership structure on grassland conservation

This study finds that a hybrid property structure, where private ownership and communal ownership coexist, outperforms pure private or pure public ownership in terms of grassland conservation after a grassland tenure reform in China. The tenure reform of privatization replaced public ownership gradually and led to a significant 5.4% increase in grassland quality on average. The grassland quality increase is twice as large for private grassland with additional access to public grassland compared to those without such access. Interestingly, public grassland quality did not decline, indicating sustainable utilization by herders. These findings are consistent with the literature which suggests that a properly structured hybrid ownership arrangement could benefit from the positive effects of grassland privatization while mitigating the negative impacts of natural disasters. We further provide empirical support and show that the gains from public grassland access are substantially larger when there are adverse climatic shocks. Our study provides important policy implications for property rights and sustainable grassland management under more frequent climate events.

Mechanical mowing of semi‐natural grasslands compromises soil quality and survival of a conservation target plant species

Mowing is a crucial management strategy for conservation and restoration of semi‐natural grasslands. In the past decades, dominant mowing methods have changed from manual to mechanical, using heavy machines causing soil compaction. Whereas the negative effects of compaction are well understood in agriculture and forestry, they have received little attention so far in nature management. This study aims to investigate the effects of compaction on soil quality, arbuscular mycorrhizal fungal communities, and survival of a target plant species. We subjected seven grasslands to three contrasting mowing types: manual mowing with a brush cutter, softtrack mowing—designed to minimize soil compaction—and tractor mowing. We compared compaction, soil properties, and arbuscular mycorrhizal communities among the types. Additionally, we experimentally subjected intact grassland sods containing Devil's bit scabious (Succisa pratensis Moench), a target species of grassland conservation, to compaction levels corresponding to the three mowing types. Subsequently, we assessed plant survival. We found that soil compaction, soil nutrient availability, and toxic soil elements were significantly higher in the softtrack‐ and tractor‐mown parts of grassland sites compared to the manually mown parts. Also, the arbuscular mycorrhizal community composition differed significantly among mowing types, with the largest differences between “manual” and “tractor.” Succisa pratensis survival significantly decreased by 43 and 71% on the short term and by 71 and 86% on the longer term with increasing compaction. Consequently, mowing‐associated soil compaction compromises nature management targets via at least four mechanisms: nutrient enrichment, soil toxicity, changes in arbuscular mycorrhizal communities, and decreased survival of the target plant species.

Classification Model of Grassland Desertification Based on Deep Learning

Grasslands are one of the most important ecosystems on earth, and the impact of grassland desertification on the earth’s environment and ecosystem cannot be ignored. Accurately distinguishing grassland desertification types has important application value. The appropriate grazing strategies can be implemented based on these distinctions. Grassland conservation measures can be tailored accordingly. This contributes to further protecting and restoring grassland vegetation. This project takes color images labeled with the desertification types of grasslands as the research object, uses the currently popular deep learning model as the classification tool, and then establishes a color image-based grassland desertification classification model based on the feature extraction network, based on the Vision Transformer model, by comparing the various deep learning image classification models. The experimental results show that, despite the complex structure and large number of parameters of the grassland desertification classification model obtained in this project, the test accuracy rate reaches 88.72% and the training loss is only 0.0319. Compared with the popular classification models such as VGG16, ResNet50, ResNet101, DenseNet101, DenseNet169, and DenseNet201, and so on, the Vision Transformer demonstrates clear advantages in classification accuracy, fitting ability, and generalization capacity. By integrating with deep learning technology, the model can be applied to grassland management and ecological restoration. Mobile devices can be used to conveniently capture image data, and information can be processed quickly. This provides efficient tools for grazing managers, environmental scientists, and conservation organizations. These tools assist in quickly assessing the extent of grassland desertification, optimizing grassland management and conservation decisions. Furthermore, strong technical support is offered for the ecological restoration and sustainable management of desertification grasslands.

Characteristics of Vegetation and Soil of Degraded Grasslands and Their Relationships in Xizang

To investigate the characteristics of grassland degradation on a regional scale in Xizang, data on grassland degradation from the second grassland survey of Xizang and 12 vegetation and soil indicators from the National Tibetan Plateau Data Center were collected. Using ArcMap, 10 000 random sample points were selected on raster data （excluding non-grassland, desertification, and salinization data, leaving 7 949 valid sample points）. The multi-value extraction to-point method was applied to extract degradation and indicator data for each sample point. The characteristics of degraded grassland vegetation and soil and their relationships were analyzed in Xizang. Moreover, random forest modeling was conducted to predict the trend of grassland ecosystem changes. The results indicated that： ① The grasslands in Xizang were primarily composed of alpine steppe and alpine meadow types, accounting for 45.83% and 41.15% of the valid sample points, respectively. ② With the intensification of grassland degradation, the number of steppe-type species among the 17 grassland types gradually decreased, and the proportion of steppe dominated by species such as Stipa purpurea and Carex moorcroftii decreased, whereas the proportion of miscellaneous grasses and Dasiphora fruticosa increased. ③ As the degree of degradation increased, vegetation indicators generally showed a declining trend, with soil total nitrogen, total phosphorus, total potassium, and organic carbon decreasing, whereas soil pH and bulk density increased, and soil moisture content was not significant. ④ A positive correlation exists between soil moisture content, total nitrogen, total phosphorus, total potassium, organic carbon, vegetation cover, net primary productivity of vegetation, normalized difference vegetation index, aboveground biomass, and habitat quality. However, there was a negative correlation between pH and soil bulk density, and the correlation coefficients among various indicators decreased with the intensification of degradation. ⑤ The random forest simulation results showed that during the degradation process, the contribution rates of soil bulk density and habitat quality both exceeded 12%, with the model prediction accuracy reaching 78%. The study revealed that grassland degradation in Xizang was closely related to soil bulk density and habitat quality, indicating that higher soil bulk density or lower habitat quality may correspond to more severe grassland degradation. This provides a scientific basis for future grassland conservation and management.

Landscape-scale predictions of future grassland conversion to cropland or development.

Grassland conservation planning often focuses on high-risk landscapes, but many grassland conversion models are not designed to optimize conservation planning because they lack multidimensional risk assessments and are misaligned with ecological and conservation delivery scales. To aid grassland conservation planning, we developed landscape-scale models at relevant scales that predict future (2021-2031) total and proportional loss of unprotected grassland to cropland or development. We developed models for 20 ecoregions across the contiguous United States by relating past conversion (2011-2021) to a suite of covariates in random forest regression models and applying the models to contemporary covariates to predict future loss. Overall, grassland loss models performed well, and explanatory power varied spatially across ecoregions (total loss model: weighted group mean R2=0.89 [range: 0.83-0.96], root mean squared error [RMSE]=9.29ha [range: 2.83-22.77ha]; proportional loss model: weighted group mean R2=0.74 [range: 0.64-0.87], RMSE=0.03 [range: 0.02-0.06]). Amount of crop in the landscape and distance to cities, ethanol plants, and concentrated animal feeding operations had high variable importance in both models. Total grass loss was greater when there were moderate amounts of grass, crop, or development (∼50%) in the landscape. Proportional grass loss was greater when there was less grass (∼<30%) and more crop or development (∼>50%). Some variables had a large effect on only a subset of ecoregions, for example, grass loss was greater when ∼>70% of the landscape was enrolled in the Conservation Reserve Program. Our methods provide a simple and flexible approach for developing risk layers well suited for conservation that can be extended globally. Our conversion models can support conservation planning by enabling prioritization as a function of risk that can be further optimized by incorporating biological value and cost.

Scale dependency of taxonomic and functional diversity in pristine and recovered loess steppic grasslands

Widespread campaigns on forest restoration and various tree planting actions lower the awareness of the importance of grasslands for carbon sequestration and biodiversity conservation. Even lower attention is given to the conservation of biodiversity and ecosystem functioning in remnants of ancient, so-called pristine grasslands. Pristine grasslands generally harbour high biodiversity, and even small patches can act as important refuges for many plant and animal species in urbanised or agricultural landscapes. Spontaneous succession of grassland is frequently viewed as a cost-effective tool for grassland restoration, but its applicability is strongly dependent on many local to landscape-scale factors, and the recovery is often slow. It is therefore essential to monitor the success of grassland restoration projects that rely on spontaneous succession. We compared the species diversity and functional attributes of pristine and recovered grasslands by studying the taxonomic and functional diversity in thirteen (8 pristine and 5 recovered) loess steppic grasslands using differently sized sampling plots from 0.01 to 100 m2. Our results indicate that there are remarkable differences in taxonomic and functional diversity between pristine and recovered grasslands. We also found that during secondary succession there is a likely functional saturation of the species assembly in the first few decades of recovery, and while patterns and structure of recovered grasslands became quite similar to those of pristine grasslands, species richness and diversity still remained much lower. Pristine grasslands support considerable plant diversity, and species composition is slow to recover if destroyed by agricultural land use. This underlines the importance of preserving existing pristine grassland remnants, which might serve as sources of species for future restoration measures.

Natural grazing by horses and cattle promotes bird diversity in a restored European alluvial grassland.

A challenge in grassland conservation is to maintain both the openness and the heterogeneity of the habitat to support the diversity of their animal communities, including birds-a taxon that is known to be sensitive to disturbance. An increasingly used management tool in European grassland conservation, especially in rewilding projects, is grazing by large herbivores such as horses and cattle. These grazers are believed to create and maintain patchy landscapes that promote diversity and richness of other species, but their influence on birds is often debated by conservationists, who raise concerns about the impact of disturbance by the grazers. Our aim was to examine the relationship between the abundance and species richness of birds across four foraging guilds and the area utilization patterns of Highland cattle and Konik horses in an alluvial grassland in France. We also aimed to examine the influence of land cover and season on the spatial distribution, including abundance and species richness, of different bird guilds present in the grazed area. We used GPS-collars on all grazers and recorded their positions on an hourly basis over a study period of 1.5 years, assessing patterns of area usage. We counted birds weekly along three transects to describe their distribution within the grazed area and carried out land-cover surveys to describe the habitat. To assess how species richness and abundance of birds of different guilds were related to grazer density, season, and habitat characteristics, we used GAMM models in a spatially explicit framework. We also compared bird numbers at our main study site with a nearby non-grazed control area. The number of birds in the grazed area was about twice the number in the non-grazed control area. Within the grazed area, the abundance of open-area foraging birds increased with increasing grazer density. The number of woodland-foraging birds was also positively correlated with grazer density but less so than open-area foraging birds. The number of individuals in the aerial and wetland bird guilds was not correlated with the density of grazers. Most bird species and individuals were observed on open landscapes scattered with woody patches and waterbodies, and on areas with moderate grazer density. Low-intensity grazing represents a potentially important management tool in creating heterogeneity in alluvial grasslands, thereby promoting suitable habitat for a diverse assemblage of bird species.

Collective action in the pastural area of Inner Mongolia, China: Evidence from a lab-in-the-field experiment

The degradation of grasslands is a pressing global issue. Extensive research has explored the implementation of collective action as a means to ensure the sustainable use of grassland resources. However, empirical analysis of its impact in the field is lacking. Therefore, we conducted a lab-in-the-field experiment to evaluate the intensity of herders’ participation in collective action and estimated its impact on grassland conservation and livestock production at herder household level. As a robustness check, we performed a principal component analysis to measure herders’ willingness to participate in collective action. The empirical results show that collective action has significant positive effects on grassland quality and livestock number. A mechanism analysis indicates that herders who are more actively engaged in collective action are more likely to adopt rotational grazing management practices, leading to better grassland quality and a higher number of livestock. A heterogeneity analysis reveals that the benefits of collective action on grassland conservation vary based on resource endowments and individual characteristics, including grassland area and social network. This study makes a significant contribution to the study of sustainable grassland management that promotes the coupling development of grassland protection and livestock production.

Seed dispersal limitation causes negative legacy effect on restoration of grassland plant diversity on ski slopes.

Past forest use often has a long-term negative impact on the recovery of the original plant composition of semi-natural grasslands, which is known as a legacy effect. This study investigates the impact of seed dispersal limitations on the restoration of grassland plant diversity on ski slopes with past forest use, highlighting the negative legacy effect on biodiversity recovery. Focusing on ski areas, our research contrasts the vegetation on ski slopes originally created on semi-natural grasslands such as pasture (pasture slopes) and constructed by clearing secondary forests or conifer plantations (forest slopes). We examined species richness and diversity, considering seed dispersal modes, grassland management history, and seed source proximity. We reveal that the proximity to species-rich grassland sources is pivotal for the restoration of native grassland vegetation. Particularly, wind-dispersed species show significant recovery on slopes with sustained management for more than 70 years and those with neighboring species-rich grasslands, suggesting that both the duration of management and the proximity to seed sources are critical for overcoming the legacy effects of past forest use. Meanwhile, gravity-dispersed species failed to recover their richness and diversity regardless of both the duration of management and the proximity to seed source grasslands, which their diversity recovered where seed sources neighbored. Our findings emphasize the importance of considering seed dispersal limitation and management history in the restoration and conservation of grasslands and their biodiversity, particularly in landscapes experiencing past human intervention.

Dry grasslands in urban areas can harbour arthropod species of local conservation concern and should be prioritised for biodiversity‐friendly mowing regimes

Abstract Although urbanisation is one of the greatest threats to biodiversity, its effect on particular invertebrate groups remains ambiguous on local and landscape scales. We aimed to analyse the effect of urban grassland management on spiders (Araneae) and carabids (Coleoptera: Carabidae), as well as other local and landscape parameters. We investigated 27 grasslands of two different management intensities (‘extensive’: one to two late cuts with removal of biomass [n = 18]; ‘intensive’: three to five mulching cuts [n = 9]) in the city of Karlsruhe, Germany. Pitfall trapping and sweep netting were performed to sample carabids and spiders. Results indicate that urban grasslands in Karlsruhe are inhabited by species‐rich assemblages, including several species of conservation concern (cc). Latter remain mostly restricted to dry grassland. The number of total specimens and of those belonging to species of cc were negatively affected by intensive management. The number of specimens of species of cc further decreased with increasing humidity and in spiders, additionally, by vegetation height. Landscape factors had limited effects, and only isolation of meadows negatively influenced the species richness of carabids (total and of species of cc). Our results demonstrate that conservation of dry grasslands in urban areas is crucial for sustaining local arthropod communities. Dry urban grassland may also act as a refugium for species of cc and mitigate the global insect crisis on a local and regional scale. In conclusion, biodiversity‐friendly mowing regimes should be applied on a broader scale in urban areas and target especially dry grassland plots. In addition, increasing connectivity and permeability of the urban matrix assist the colonisation by species of cc.

Challenges of Orthoptera conservation in grasslands with land use-determined sizes and structural heterogeneity

Challenges of Orthoptera conservation in grasslands with land use-determined sizes and structural heterogeneity

Effect of Vegetation Structure on Lift-Off and Dispersal Velocities of Diaspores with Different Morphological Characteristics in Secondary Wind Dispersal

Diaspore dispersal is crucial in shaping plant population dynamics, biodiversity, and ecosystem functions. The effect of the vegetation structure on the secondary wind dispersal of diaspores with different appendage types is not well understood. Using a wind tunnel and a high-definition video camera, we accurately measured the lift-off and dispersal velocities of diaspores from sixteen plant species across six wind velocities (2, 4, 6, 8, 10, and 12 m s−1) under six simulated vegetation structures. Vegetation structure and appendage type were pivotal factors, explaining 41.1% and 42.3% of the variance in lift-off velocity and accounting for 12.0% and 25.3% of the variability in diaspore dispersal velocity, respectively. Vegetation coverage was the main factor influencing near-surface wind velocity, and the lift-off and dispersal velocities of diaspores changed significantly when vegetation coverage exceeded 40%. Diaspores with one wing, having high lift-off velocities and low dispersal velocities, adopt the anti-long-distance wind dispersal strategy, whereas diaspores with pappus, having low lift-off velocities and high dispersal velocities, adopt the long-distance wind dispersal strategy. In contrast, diaspores with thorn, discoid, balloon, and four wings adopt the non-long-distance wind dispersal strategy, suitable for environments such as low-coverage deserts and desert steppes but not high-coverage typical steppes. This study could help comprehend the effect of the vegetation structure on the dispersal process of diaspores, which facilitate habitat restoration and biodiversity conservation of grassland and forest ecosystems.