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Our objectives were to examine the species composition and diversity of soil seed bank (SSB) and standing vegetation (SV), explore association between compositional diversity of SV, SSB and selected environmental factors and assess the implications of SSB on regeneration of flooded riparian vegetation in Hamedan province, Iran. We estimated the ground cover of SV and SSB composition in 90 plots (1 m × 1 m) distributed across 15 sites in the river riparian zone. We evaluated the SSB by seedling emergence method. Canonical correspondence analysis (CCA) was used in a direct gradient analysis of the SV/SSB with the environmental factors. In total, 136 species were identified from germinated seed bank in the greenhouse and there were 131 plant species recorded in the aboveground vegetation. 31 species were observed in the SSB while they were absent in the SV, while there were also 26 species that were only present in the SV. Dominant species in the SSB were floatable seed species, i.e. Cyperus difformis and Dactylis glomerata. In addition, the results indicated a more pronounced effect of environmental factors on SV than on SSB distributions in which a higher number of environmental factors associated significantly with SV than with SSB (6 vs. 4). However, elevation, soil moisture content and total organic matter had significant effects on community distribution of both SSB and SV. The species diversity and composition evenness were significantly higher in the SSB than SV. Although, 105 species were common to SSB and SV, the mean Czekanowski similarity between SV and SSB was very low (15.5%). However, we argue that the recovery of vegetation in degraded sites can still rely on SSB. We concluded that the seed movement among plant communities through hydrochory led to a spatial homogenization of SSB, resulting in a decrease in SSB-SV similarity and an increase in SSB species diversity and compositional evenness. Differences in plant diversity and richness between the SSB and the SV are supposed to be a complementation of diversity between below- and above-ground and therefore, greater community resilience is predicted under stochastic disturbance events such as flooding in the riparian area. [ABSTRACT FROM AUTHOR]

Rehabilitation strategies for degraded mine dumps have generally seen limited success due to different complications associated with mining biophysical disturbance. In this study, we tested a combination of two methods to expedite revegetation of kimberlite tailings at Letseng Diamond Mine (i.e., in the Afro‐alpine areas of Lesotho). We ran trials on different growth media located on fine and coarse kimberlite tailings (i.e. sites) mixed with different substrate combinations and topsoil and sowing a seed mix comprised of native plant species. Overall, as predicted, fine kimberlite tailings displayed significantly higher plant abundance than coarse kimberlite tailings, and sown seeds performed significantly better than spontaneous colonisation by emerging species. Kimberlite tailings mixed with topsoil (100 mm) showed significantly greater plant abundance, and similarly, when coarse kimberlite tailings were introduced to fine tailings. Physicochemical analyses of growth media components suggested that topsoil provided additional nutrients and that plants could readily access available nutrients in the fine kimberlite tailings. We noted a gradual significant increase in plant abundance over 5 years, enhanced by new plant species emerging from the topsoil seed bank or by natural seed dispersal. Although plant abundance differed significantly, both fine and coarse kimberlite tailings displayed high plant species diversity (H = 3.4 and D = 0.95 and H = 3.5 and D = 0.95, respectively). Out of 36 emerging plant species, 15 species spontaneously colonised both growth media. The significant variation in abundance among plant species between treatments was mostly attributed to dominant forb species, namely Chrysocoma ciliata, Glumicalyx montanus, Oxalis obliquifolia, Senecio inaequidens and Trifolium burchellianum. We have identified suitable growth media for plant community restoration on kimberlite tailings in the Drakensberg alpine area using a seed mix of native plant species in combination with natural seed dispersal from the surrounding pristine environment. We provide evidence for using two complementary approaches to optimise native plant community development during restoration in the Drakensberg alpine area. [ABSTRACT FROM AUTHOR]

Question: Riparian vegetation and seed banks are the foundation of functional riparian zones, yet insight in the processes that explain their composition is limited. We tested three theories fundamental to dispersal and environmental filtering of riparian seed banks and vegetation. Combining these theories, we expected hydrochory to lead to increased species richness downstream in both soil seed bank and vegetation with accumulation restarting after a lake section, and geomorphological filtering to lead to higher similarity of seed bank and vegetation composition locally and within lakes, slow‐flowing sections and rapids, respectively, than between them. Location: Svartån, a free‐flowing river in central Sweden. Methods: We surveyed riparian vegetation and conducted a germination experiment on riparian soil seed bank cores from lakes, slow‐flowing sections and rapids. We combined these with trait data on seed dispersal syndromes, floating capacity of seeds and seed longevity. We analysed differences throughout the system with linear models and between process domains with Kruskal–Wallis tests and similarity in community composition with the Horn–Morisita similarity index. Results: Our results indicated that species richness did not increase downstream and was relatively similar throughout lakes, slow‐flowing sections and rapids for both riparian seed banks and vegetation. Seed floating capacity was similar throughout these river sections, too, and seed longevity was higher in seed banks than in vegetation. Conclusions: Geomorphology and hydrochory were not as important drivers in this area for riparian seed bank and vegetation composition as expected. In the area and on the scale studied here, other local and regional environmental factors and dispersal syndromes are more likely to be determinants of riparian dynamics and composition. Continued studies of riparian seed banks can help improve our understanding of riparian composition and functioning in the future. [ABSTRACT FROM AUTHOR]

To effectively restore species and habitat diversity in poorly managed degraded grasslands, it is important to understand the relationship between the soil seed bank and aboveground vegetation. Our study aimed to describe changes in soil seed bank composition compared to aboveground vegetation under two ploughing regimes (annual and single ploughing) of narrow strips on the edges of artificially grassed old fields in Podyjí National Park, the Czech Republic. We used the seed germination method, multivariate analyses and Kruskal–Wallis tests to compare differences in the proportion of species and individual numbers in the soil seed bank based on the origin of species (native species, archaeophytes, neophytes) and their habitat preferences (segetal, ruderal, grassland, endangered species) in two types of grasslands with varying soil moisture content. The highest numbers of individuals were present in annually ploughed dry grasslands whereas single ploughing in mesic grasslands resulted in greater species diversity. Ploughing increased the numbers of seedlings of all groups and promoted archaeophytes, grassland specialists, native species and ruderals in dry grasslands whereas mesic grasslands hosted segetal specialists and neophytes. Threatened plants and invasive species rarely emerged from the soil seed bank. The study also revealed the highest similarity between the soil seed bank and aboveground vegetation in annually ploughed plots. It gradually decreased during vegetation succession in the single ploughed variants. Whereas annual ploughing supported segetal specialists, single ploughing promoted grassland species in dry habitats. Neither type of ploughing can be recommended in mesic grasslands because of the risk of inducing the spread of expansive ruderals or invasive neophytes. [ABSTRACT FROM AUTHOR]

Wright fishhook cactus is a small globose cactus endemic to an area of 280,000 ha in south-central Utah and was listed as endangered in October of 1979 by the U.S. Fish and Wildlife Service (USFWS). There is a general paucity of information about this species, and no published data on the seed bank for any species in the genus. Our objective with this study was to provide insight into the established seed bank density for this species. We processed 500 soil samples from various locations near individual cacti and potential neighboring nurse plants. We found that the species had a detectable seed bank of a size similar to other members of the Cactaceae family. Seed bank densities were the highest immediately adjacent to, and downslope from, parent plants. Our data indicate that areas within 20 cm of seed-producing cacti contain by far the greatest density of seeds. These areas should be given special consideration in future management plans for this species. [ABSTRACT FROM AUTHOR]

Many Astragalus species exhibit seeds with physical dormancy (PY), but little is known about the ecological context of this dormancy. We focused on A. maritimus and A. verrucosus, two threatened Sardinian endemic species inside the subgenus Trimeniaeus Bunge. Fresh seeds collected from the only two respective known populations were used to investigate the effect of mechanical scarification, heat shock, and water imbibition processes on PY release and germination. PY can be overcome through mechanical scarification of the water-impermeable seed coats, while no dormancy break was detected, nor a subsequent increase in seed germination due to fire-induced heat. This suggests that fire does not trigger dormancy release and seed germination in these species. The seeds tolerate relatively high heat shock temperatures (up to 120 and 100 °C for A. verrucosus and A. maritimus, respectively), but after 120 °C for 10 min, the number of dead seeds increases in both species. These facts suggest the capacity to develop a soil seed bank that can persist after fires and delay germination until the occurrence of optimal conditions. As regards water imbibition, both Astragalus species did not show the typical triphasic pattern, as germination started without further water uptake. This study emphasizes the significance of understanding germination processes and dormancy in threatened species. In fire-prone ecosystems, PY dormancy plays a crucial role in soil seed bank persistence, and it may be selectively influenced by post-fire conditions. Understanding such adaptations provides useful insights into conservation strategies. [ABSTRACT FROM AUTHOR]

The soil seed bank present in forests serves as a crucial indicator of soil resilience following disturbances. The objective of this study was to investigate the composition, density, and vertical distribution of the soil seed bank in the Diga District of Western Ethiopia across four land use types: forestland, grassland, bare land, and shrubland. Soil samples were collected from plots measuring 225 square centimeters with a depth of 9 cm. A total of 108 soil samples were collected, representing the four land use types. Each plot was sampled at three different soil layers: 0–3 cm, 3–6 cm, and 6–9 cm depths. From the soil seed bank, 51 plant species were identified, with 46 (90.2%) being herbs, 3 (5.88%) trees, and 2 (3.92%) shrubs. The Asteraceae (13.30%), Poaceae (11.53%), and Fabaceae (9.61%) families exhibited the highest species composition, accounting for 38.44% of the total. Species richness varied significantly across all land use types and soil layers (p < 0.05), with shrubland having the highest species richness and bare land having the lowest count. The total seed bank density in the soil across all plots was 92153 seeds/m2, with the highest density observed in the top 3 cm of the soil layer. The first and second soil layers exhibited a high Jaccard similarity coefficient of 0.76. Forestland and shrubland displayed the highest Jaccard coefficient of similarity (0.72), while the lowest was observed between bare land and shrubland (0.43). There was greater species similarity between the first and second soil layers (0.76) and lower similarity between the middle and bottom layers (0.32). The study found limited similarity between aboveground vegetation and the soil seed bank due to the low regeneration of woody species. Forestland and shrubland exhibited a high Jaccard similarity coefficient to aboveground vegetation, while grassland had the lowest similarity coefficient. Based on the findings, it can be concluded that the shrubland land use types had high soil seed bank composition and density. Therefore, the conservation of shrubs in the Arjo-Diga Forest should be considered for the restoration of degraded areas, taking into account the soil seed bank in the shrubland ecosystem. [ABSTRACT FROM AUTHOR]

Granivores, such as rodents and harvester ants, are common in dryland ecosystems. In intact dryland ecosystems, the effects of such granivores on soil seed banks, plant community structure, and ecosystem functioning are well established. However, the effects of granivores on dryland restoration have received much less attention. In this study, we evaluated the seasonality of seed removal by harvester ants, seed preference of harvester ants, and effects of granivore exclosure on the soil seed bank at four sites in southeastern Utah. We studied two species of harvester ants, Pogonomyrmex rugosus and P. occidentalis. The foraging behavior of Pogonomyrmex spp. was temperature‐dependent; they removed no seeds during winter months, and up to 80% of seeds during high activity in the summer. Despite seasonal differences in seed removal, Pogonomyrmex spp. did not show significant preferences for seed species. However, their seasonal foraging behavior translated into measurable differences in an experimental soil seed bank. Over the summer months, ants reduced the number of seeds in the seed bank by approximately 20%, but when ants were excluded during the winter, the number of seeds in the seed bank remained the same. This finding supports the timing of business‐as‐usual seeding practices of applying seeds in late fall. If seeds germinate in the first season after application, ant granivory is unlikely to pose a large barrier to establishment. However, if seeds remain dormant during the first year, as is common in many dryland species, seeds are vulnerable to ant granivory. [ABSTRACT FROM AUTHOR]

Ecological systems are severely damaged by the anthropogenic disturbance of mining. Phosphate open‐pit mining fields cover over 200 km2 of the Negev desert, Israel. However, the effects of the ongoing mine site restoration efforts on the plant community have not been studied. Plants and their seed banks have a major role in ecosystem processes and restoration. In this study, we focused on three mining sites, restored in different years, along Zin River valley. We compared the plant community of restored mining plots within these areas to adjacent natural plots. We asked whether plant community germination potential from the soil seed bank differs between the restored plots and the adjacent natural plots within a mining site. We hypothesized that: (1) there is a lack of seed bank in the restored plots; (2) the altered soil composition at the restored plots inhibits germination. We used soil samples collected from the different mining sites and set up greenhouse experiments. One experiment compared natural and restored areas with different soil treatments. In another experiment, we added native seeds to test their germination potential on restored soil. Our results indicate that lack of seed bank is the major limiting factor hindering germination and not the composition of the soil after restoration. Our findings shed light on the constraints of seed bank establishment in post‐mining areas of hyper‐arid regions. We suggest considering active restoration practices to facilitate natural dispersal and improve seed bank establishment. [ABSTRACT FROM AUTHOR]

The assessment of seed banks could provide useful hints towards ensuring restoration planning and invasive species management. In this study, the impacts of two invaders such as Hyptis suaveolens and Urena lobata on the soil seed banks were investigated. We also assessed the seed characteristics of the invaders at the invaded sites. This was achieved using 10 sites each for H. suaveolens- and U. lobata- invaded habitats and -non-invaded habitats making a total of 30 sites. We collected 200 soil samples from each habitat type. A seedling emergence method was used to determine the seed bank recruitment of both invasive plants. The diversity indices of the above-ground vegetation of sites invaded by the two plants were significantly lower than those of the non-invaded sites. Only two plant species emerged from the seed banks of H. suaveolens and five plants from those of U. lobata when compared with non-invaded sites where 53 species emerged. A larger portion of the seeds was located in the soil's lower layer at all the sites invaded by H. suaveolens while those of U. lobata and non-invaded sites were found in the upper layers and there are significant associations between the habitats. The lower soil layers of the two species have the highest percentage of viable seeds. These results help us to understand more about the invasiveness of both species as related to their impacts on the seed banks and native vegetation. It also indicates that the native species that emerged from the invaded seed banks could be used for the restoration of the invaded habitats. [ABSTRACT FROM AUTHOR]

The soil seed bank could be viewed as an optimisation of the chances of plants to meet favourable conditions in time and space. Owing to the large number of publications and the field's complexity, available reviews do not cover the entire field. My objective was to produce a synthesis. Determination of the soil seed bank needs careful planning of sampling because of variations in soil depth and clumped distributions. Sample composition is determined from plantlets coming from germinated seeds after exposure to appropriate conditions or directly from seeds after their separation from soil particles. Seed longevity varies from months to decades and depends on desiccation resistance, defences against predators and germination control, notably dormancy. Dormancy characterisation and alleviation factors allow to understand species' strategies in ecosystems. In agricultural soils, weeds challenge future cultures. Research objectives are often to exhaust their seed banks before crop emergence by reducing seed production, inactivating germination, removing weeds before seed maturation, and controlling the harvest. In natural ecosystems, climax species tend to produce shorter-lived seeds compared to pioneered ones. The soil seed bank may help in restoring degraded vegetation but the similarity with the aboveground vegetation is low. Disturbances may increase or decrease the soil seed bank diversity. Restoration may often rely on natural recruitment from undisturbed areas or on artificial translocation. I emphasise the need to integrate soil seed bank knowledge into dynamic vegetation models, which generally lacks most of the soil seed bank features, while the future distribution of the plant species is one of the main questions in this climate change era. [ABSTRACT FROM AUTHOR]

In anthropized sites, the establishment and management of sustainable and nature-based wildflower meadow solutions exclude fertilization, weeding, and watering, and reduce the frequency of mowing. Once such inputs have been reduced, the ecosystem services generated by the vegetation result in an increase in biodiversity in terms of plant and animal species, an improvement in soil quality and biota, the mitigation of air pollutants and carbon sequestration, as well as a reduction in soil temperature. Environmental education and citizen science are also some of the benefits of this type of vegetation, especially in urban areas. Herbaceous meadow-like communities, which are composed of forbs only or a combination of graminoid and forb species, are usually established by sowing. The seeds are available for purchase from specialized seed producers as single species or in a mix, some companies offer mixes composed of garden species with botanical species. Donor meadows are the sources of the genetic material and the template to reproduce the meadow herbaceous community at different sites through seed harvest, hay harvest, and the displacement of soil with its seed bank. Management techniques, such as soil preparation, determining the appropriate sowing and mowing time, can help in establishing and maintaining the most desirable species. The suspension of urban turf mowing allows the growth of the natural seed bank, which in unproductive soils facilitates the appearance of many pollinator-friendly herbaceous species. With the appropriate pedological conditions and management, the natural urban herbaceous vegetation thus provides beautiful and rich plant communities, which are also easy to maintain. This review identifies the best practices through a qualitative selection of case studies related to the various methods to establish wildflower meadows in the urban infrastructure and the main constraints such as the lack of a suitable seed market. [ABSTRACT FROM AUTHOR]

Summary: Information on seed persistence and seedling emergence from the soil seed bank is critical for understanding species coexistence and predicting community dynamics. However, quantifying seed persistence in the soil is challenging; thus, its association with other life‐history traits is poorly known on a broad scale.Using germination phenology for 349 species in a 42‐yr experiment, we quantified the persistence–emergence correlations and their associations with intrinsic regeneration traits using Bayesian phylogenetic multilevel models.We showed no trade‐off between seed persistence and seedling emergence. Physically dormant seeds were more persistent but exhibited lower emergence than nondormant seeds. Monocarpic species had both higher persistence and emergence than polycarpic species. Seed mass posed a marginal proxy for persistence, while emergence almost doubled from the smallest to the largest seeds.This study challenges the traditional assumption and is the first demonstration of noncorrelation between persistence and emergence, probably owing to the complexity of regenerative strategies. Species with short persistence and low emergence would be the most vulnerable for in situ conservation. Our analyses of this unique, long‐term dataset provide a strong incentive for further experimental studies and a rich data resource for future syntheses. See also the Commentary on this article by Meitzel, 241: 521–522. [ABSTRACT FROM AUTHOR]

The composition and structure of soil seed banks provide insight into the long-term implications of plant invasions on resident communities. The effect of Salpichroa origanifolia (Sa) on the seed bank of a coastal mesophile forest (Tuscany) was studied by growing Sa-rhizomes in soils from low and high invaded sites, in full sun and canopy shade. Sa growth patterns, and the composition, biomass, nitrogen, and phosphorus contents of seedlings which emerged from seed banks were determined. Seed bank abundance and richness were also determined from under and 2 m apart established Sa populations. Sa plants' leaf traits and biomass allocation changed in response to light conditions. The germination of seed bank seedlings was not affected or even promoted by Sa, while their biomass as well as N and P uptake were more than halved in both light conditions, leading to a progressive depletion of the forest seed bank. Richness was lower under established Sa populations. Sa seedlings exerted a greater suppression on residents than Sa adults, and these appeared more competitive against their own seedlings than on residents. Sa is an invader of concern for Mediterranean forests because of its adaptability to shaded conditions, the competitiveness of its seedlings, and its vegetative spread by means of rhizomes. [ABSTRACT FROM AUTHOR]

Fabaceae produce seeds with water‐impermeable seed coats, i.e., physical dormancy (PY). We hypothesized that the proportion of PY seeds will increase with the dryness of the habitat, and some key seed ecological traits will be strongly associated with different levels of PY.Fresh seed of 25 Fabaceae species collected in northern India were used for imbibition and germination experiments to determine the proportion of seeds with PY and of nondormant (ND) seeds compared to their Sri Lankan congeners. Seed coat:seed mass ratio (SCR), 1000 seed weight, seed shape index (SSI), embryo type and median germination time of ND seeds were determined.Four imbibition and germination patterns were identified among seeds of the studied species. Seeds collected from Indian populations had a higher proportion of PY seeds than those of Sri Lankan populations. We identified a type of embryo called 'spatulate axile' that had not been identified before among the studied species. Species with ND seeds had a lower SCR and a higher SSI than those with PY.Our hypothesis was confirmed since populations from drier habitats in India produce a higher proportion of PY seeds than those from Sri Lanka. A low SCR ensures minimal resistance to germinating seeds, while seeds with a high SSI have a lower tendency to incorporate into the soil seed bank. Thus, these seed traits aid the fast germination of ND seeds, often dispersed just before the rainy season. [ABSTRACT FROM AUTHOR]

Questions: What role do soil seed banks play in the resilience of coastal freshwater wetland vegetation communities? How might soil seed bank composition and similarity to standing vegetation drive changes in vegetation expression, particularly given projected changes in climate? Location: Sixty wooded coastal freshwater wetlands in southeast Queensland, Australia. Methods: We surveyed standing vegetation and investigated soil seed bank composition through an 8‐month‐long emergence experiment. Results: Soil seed bank assemblages were dominated by forb and sedge species (23% exotic), but composition varied throughout the study region. Spatial (north–south) and land‐use (urban–rural) gradients explained some variation in soil seed bank composition. Soil moisture and groundwater dependence also influenced species distributions, particularly for freshwater wetland species. The similarity of soil seed banks to standing vegetation was low. Species present in both extant and soil seed bank assemblages were commonly native wetland taxa, including one salt marsh species (Juncus kraussii). Conclusions: Projected climatic changes will likely drive changes in coastal freshwater wetland vegetation communities through increases in the frequency and intensity of disturbances (e.g., storm surge). Our results suggest that regeneration from soil seed banks could promote four potential scenarios: (1) expansion of weed communities, (2) expansion of salt marsh communities, (3) maintenance and expansion of wetland/terrestrial species, and (4) transformation to an unvegetated open water zone because of reduced regeneration success under changing conditions. These diverse vegetation futures highlight the vulnerability of wooded coastal freshwater wetlands and the need for research and management interventions to maintain their biodiversity and ecosystem services. [ABSTRACT FROM AUTHOR]

Question: Patchiness of herbaceous species is a common feature of degraded alpine grasslands on the Qinghai–Tibet Plateau; however, the impact of this phenomenon on vegetation, soil seed bank (SSB), and soil carbon (C) and nitrogen (N) is largely unknown. We asked how different herbaceous patches affect above‐ground vegetation, the SSB and soil organic C (SOC) and total N (TN) contents in alpine meadows. Location: An alpine meadow on the Qinghai–Tibetan Plateau, China. Methods: We used field and greenhouse experiments to evaluate above‐ground vegetation parameters, the SSB composition, and SOC and TN contents of four commonly distributed herbaceous patches (Leymus secalinus, Kobresia humilis, Leontopodium nanum and Pedicularis kansuensis) and non‐patch vegetation (control). Results: There were significant differences in the species composition of above‐ground vegetation, with the plant species richness, Shannon–Wiener index, Simpson index, and Pielou evenness index reduced in the four patches compared to the control. In addition, patches had increased above‐ground biomass (AGB) and a lower below‐ground biomass to above‐ground biomass ratio (BGB:AGB); while the species diversity indices did not change considerably among the patches. The species composition of the SSB in the four patches differed from that in the control and the seed density increased markedly, but the species richness and diversity of the SSB remained unaltered. Moreover, the contents of SOC, total C, TN, microbial biomass C, and microbial biomass N in the four patches were markedly lower than in the control. Conclusions: These findings suggest that patchiness of herbaceous species can alter the flora composition of alpine meadows and reduce plant species diversity, as well as the SOC and TN contents, which will adversely impact grassland biodiversity conservation and soil C sequestration, and then may intensify the degradation of alpine meadows on the Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Increased atmospheric nitrogen (N) deposition affects biodiversity in terrestrial ecosystems. However, we do not know whether the effects of N on above‐ground plant β‐diversity are coupled with changes occurring in the soil seed bank. We conducted a long‐term N‐addition experiment in a typical steppe and found that above‐ground β‐diversity increased and then decreased with increasing N addition, whereas below‐ground β‐diversity decreased linearly. This suggests decoupled dynamics of plant communities and their soil seed bank under N enrichment. Species substitution determined above‐ and below‐ground β‐diversity change via an increasing role of deterministic processes with N addition. These effects were mostly driven by differential responses of the above‐ground vegetation and the soil seed bank β‐diversities to N‐induced changes in environmental heterogeneity, increased soil inorganic N concentrations and soil acidification. Our findings highlight the importance of considering above‐ and below‐ground processes simultaneously for effectively conserving grassland ecosystems under N enrichment. [ABSTRACT FROM AUTHOR]

Seed banks are fundamentally important components of the wetland ecosystem. Water levels on germination in soil seed banks have been documented in many ecosystems. However, there is a lack of knowledge about water levels on seed banks in freshwater wetlands, especially in those buried by sedimentation. Three burial depths (0–5 cm, 5–10 cm and 10–15 cm) within five water level gradient zones along the elevation in Poyang Lake, Eastern China, were sampled. The seedling-emergence method in a greenhouse under moist conditions and submersion was applied to allow all active seeds to be germinated. The experiment continued over an eight-week period in late spring up to early summer. A total of 7090 seedlings emerged, belonged to 20 families, 36 genera and 49 species. In terms of results, an average active soil seed density of 17,328 ± 1675 seeds/m2 was found in 0–15 cm in Poyang Lake, and the greatest average seed density was found at 0–5 cm with 7607 ± 790 seeds/m2, along with 5–10 cm and 10–15 cm with 5419 ± 589 seeds/m2 and 3855 ± 790 seeds/m2, respectively. An obvious difference in composition was found in the species composition of the seed bank at different water levels and burial depths. The highest water level and top layer of soil had the highest diversity index, with a Shannon–Wiener value of 2.011. Seed density, species richness and diversity decreased with the water level gradient zone from low elevation to high elevation and burial depth from surface to deepness. However, there was no interaction between inundation duration and burial depth, indicating that the water level fluctuation and sediment buried had a separate impact on the seed bank composition and diversity index. The present findings can be directly applied to the ecosystem conservation of healthy wetlands, and the ecological restoration of devastated and degraded wetlands in Poyang Lake. [ABSTRACT FROM AUTHOR]

The UN Decade on Ecosystem Restoration 2021–2030 has launched nature conservation, environmental protection, and ecosystem services' restoration on the global environmental policy agenda. However, particularly high mountain habitats being subject to erosion are up to now hardly restorable. Erosion with associated loss of vegetation, soil, and its fertility, is one of the most urgent environmental problems throughout the world. Consequently, we analyzed the soil seed bank of calcareous high‐mountain grassland in the European Alps to reveal the natural regeneration potential after shallow erosion events. We applied a chronosequence approach taking recently eroded grassland areas (<5 years) as well as areas with earlier erosion events (>5 up to 10 and >27 years) into account. Our results revealed that the vegetation of old eroded areas was not closely similar to the surrounding intact grasslands. However, it was well differentiated from the initial stages of young and intermediate eroded areas' vegetation and had higher plant cover and species richness. The old eroded areas' seed bank had higher seed density and species richness compared to younger areas. While typical mountain meadow species were present in the seedbank of eroded areas, the assessed indicator species of both, younger and older eroded areas did not resemble the ones of the aboveground vegetation. We conclude that the seed bank has important but limited potential for the restoration of the complete species range of calcareous eroded alpine grasslands. This implies that additional restoration measures are needed to reintroduce species absent from the seed bank. [ABSTRACT FROM AUTHOR]

Natural grasslands, one of the main ecosystems worldwide, are under threat and native species are desired when addressing restoration issues. The main processes for grasslands restoration success are plant establishment and seed addition in the soil. Thus, it requires overcoming barriers that prevent germination and seed dispersal strategies. This study aimed to assess the germination potential, treatments to overcome seed dormancy and endozoochory dispersal of forage native species by cattle. Seeds from 21 native species from the four most common botanical families (Poaceae, Asteraceae, Fabaceae and Cyperaceae) were collected in a natural grassland area (Pampa Biome) and used in the experiments. Experiment I: germination under controlled conditions of all species was carried out and compared to commercial forage (Paspalum notatum cv. "Pensacola"). Experiment II: three treatments to overcome seed dormancy (mechanical and chemical scarification; priming agent) were tested in six species. Experiment III: the recovery, viability and germination of native P. notatum Flüggé and Desmodium incanum DC seeds from cattle faeces were evaluated. The results show that Paspalum umbrosum Trin. and Saccharum angustifolium Nees have high germination potential when compared to commercial forage. The treatments to overcome seed dormancy increased the germination of D. incanum, Paspalum plicatulum Michx. and Paspalum dilatatum Poir. Total seed recovery of 15% (P. notatum) and 26% (D. incanum), without affecting seed viability, show that cattle are able to supply the soil seed bank with native species. Germination potential, treatments to overcome seed dormancy and endozoochory dispersal of forage native species may be exploited in natural grassland restoration. [ABSTRACT FROM AUTHOR]

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For the prevention of hilly soils from erosion, a smart selection of crop rotations is very important. The aim of this study was to investigate the influence of different agrophytocenoses on seed numbers in the soil runoff sediments and soil seed banks' relations to soil properties in hilly landscapes. This study analyzes long-term monitoring data from three different agrophytocenoses (permanent grassland, cereal–grass crop rotation and crop rotation with a row crop) set up on slopes of 9–11° steepness with collectors for soil and water installed. The soil of the southern exposition slope was a slightly eroded Eutric Retisol. In the soil of permanent grassland, the number of seeds was 4036 seeds m−2, 6.0 and 3.2 times smaller compared to cereal–grass crop rotation and crop rotation with a row crop. The seeds found in the soil runoff sediments composed, on average, 0.9% of the soil seed bank, and the number of seeds depended on the number of days with heavy precipitation during the plant vegetation period, as well as on the plant communities grown in a particular rotation. Correlation analysis showed the seed numbers' dependence on the soil's chemical and physical properties. Hill slopes were not affected by water erosion, when agrophytocenoses were based on perennial grassland and also cereal–grass crop rotation, where reduced soil tillage was applied. [ABSTRACT FROM AUTHOR]

In many landscapes, successful re‐establisment of plant populations depends on the presence of diaspores, either near or directly beneath sites to be restored. The soil seed bank is, therefore, an important part of ecosystem resilience and a vital pillar for regeneration of genetic diversity in many plant populations. However, regeneration from the soil seed bank and the siubsequent restoration can only be considered successful when genetic diversity of restored populations is not eroded nor genetic differentiation inflated.We compared genetic variation within and among soil seed bank and aboveground populations of Origanum vulgare, to test whether genetically variable populations can be restored from the soil seed bank. We explored levels of genetic diversity within aboveground populations and the corresponding soil seed banks. Furthermore, we assessed the extent to which the soil seed bank differs genetically from the aboveground population.Levels of genetic diversity were to generally similar in aboveground populations and the corresponding soil seed banks. Only levels of inbreeding were slightly higher in the lower layer of the soil seed bank compared to the aboveground populations, probably because of selection processes acting against homozygotes accumulating in the seed bank. Furthermore, significant genetic differentiation between the aboveground population and the corresponding seed banks was completely absent. Across all sites, genetic differentiation between the soil seed bank was similar to that between aboveground populations, probably due to the absence of severe climate conditions, strong bottlenecks or disturbance events.Our conclusions support the possibility of successful re‐establishment of healthy, genetically variable plant populations after aboveground destruction or following soil re‐allocation from persistent seed banks. [ABSTRACT FROM AUTHOR]

Riparian vegetation is a keystone ecosystem element heavily impacted by livestock grazing. Historically, regeneration approaches of the riparian vegetation use either active (planting) or passive (natural regeneration) strategies. Frameworks based on an understanding of the soil seed bank are needed to help guide the approach adopted. This study compared the soil seed bank composition to the extant riparian vegetation to assess the potential for natural regeneration to supplement active plantings, following livestock exclusion on the south-coast of Australia. At each of four sites, we surveyed the extant vegetation, and collected five soil samples from each of three zones (instream, slope, bank). Our results show that the proportions of species nativeness, growth forms, and life cycle was similar for both communities. However, while there were more terrestrial species recorded in the standing vegetation, there were more wetland specialists in the soil seed bank. A persistent native seed bank, combined with other basic management strategies, could potentially compete and limit the abundance of non-native or invasive grasses. The high abundance of native grass-types (Cyperaceae, Juncaceae, Juncaginaceae, Asparagaceae, Poaceae, Typhaceae), can be relied upon to regenerate the understorey to complement active planting of the trees and shrubs. As such, resources could be prioritised to sites where native species abundance in the seed bank is low. This study recommends that land managers should investigate the composition of the soil seed bank prior to allocating resources for active planting activities to ensure the most efficient use of resources across the landscape. [ABSTRACT FROM AUTHOR]

The possible persistence of genetically modified (GM) crop-to-wild hybrid seeds in the soil seed bank is a major concern in risk assessment and is closely related to seed characteristics such as dormancy. In the present study, we generated F3 hybrids via crosses between GM soybean accessions and wild soybean and evaluated the dormancy, overwintering ability and inheritance of foreign genes in different-coloured hybrid seeds (yellow, green, brown and black). The results revealed that the 5-enolpyruvylshikimate-3-phosphate synthase transgene may have no influence on crop wild hybrid seed dormancy and overwintering ability, and the dormancy of the hybrid seeds was closely related to seed coat colour. F3 hybrid seeds with light colours (yellow and green) were relatively nondormant, while seeds that were dark (brown and black) in colour were relatively dormant. Moreover, the hybrid seeds that were dark in colour had a much stronger overwintering ability than the lighter-coloured seeds, with 21.33 % of the black seeds and 33.33 % of the brown seeds remaining viable after 240 days of soil burial. In contrast, almost all the F3 yellow and green seeds were no longer viable during winter. Scanning electron microscopy revealed that the lighter-coloured seeds had a thin palisade layer and very few surface deposits, while the darker-coloured seeds had a thicker palisade layer and a large area of honeycomb-like surface deposits similar to those of wild soybean seeds. Thus, the physical dormancy and overwintering ability of the darker-coloured seeds may be related to the seed coat. Our results suggest that transgenes of GM soybean might disperse into wild populations and persist in seed banks. [ABSTRACT FROM AUTHOR]

The soil seed bank could be viewed as an optimisation of the chances of plants to meet favourable conditions in time and space. Owing to the large number of publications and the field's complexity, available reviews do not cover the entire field. My objective was to produce a synthesis. Determination of the soil seed bank needs careful planning of sampling because of variations in soil depth and clumped distributions. Sample composition is determined from plantlets coming from germinated seeds after exposure to appropriate conditions or directly from seeds after their separation from soil particles. Seed longevity varies from months to decades and depends on desiccation resistance, defences against predators and germination control, notably dormancy. Dormancy characterization and alleviation factors allow to understand species' strategies in ecosystems. In agricultural soils, weeds challenge future cultures. Research objectives are often to exhaust their seed banks before crop emergence by reducing seed production, inactivating germination, removing weeds before seed maturation, and controlling the harvest. In natural ecosystems, climax species tend to produce shorter-lived seeds compared to pioneered ones. The soil seed bank may help in restoring degraded vegetation but the similarity with the aboveground vegetation is low. Disturbances may increase or decrease the soil seed bank diversity. Restoration may often rely on natural recruitment from undisturbed areas or on artificial translocation. I emphasise the need to integrate soil seed bank knowledge into dynamic vegetation models, which generally lacks most of the soil seed bank features, while the future distribution of the plant species is one of the main questions in this climate change era. [ABSTRACT FROM AUTHOR]

Background. Many studies have focused on the dormancy-breaking response to heat treatment of freshly matured seeds and immediately after thermal shock. Aims. We evaluated whether the full effect of dry heat scarification in freshly matured seeds could be delayed over time and the possible influence of previous storage in the soil. Methods. Adenocarpus argyrophyllus was the model species selected to explore our hypotheses by analysing the: (a) influence of scarification treatments; (b) seedling emergence during 5 years after dry heat scarification of freshly matured seeds, and evaluating intrapopulation variation; (c) seedling emergence after dry heat scarification of seeds rescued from soil; and (d) ability to form persistent soil seed banks. Key results. Dry heat scarification of freshly matured seeds only resulted in 22.5% germination. However, exposure to pre-sowing thermal shock stimulated seedling emergence during the first few years post-planting, with high intrapopulation variation. In seeds recovered from soil, thermal shock before reseeding increased the seedling emergence rate. Conclusions and implications. Our results show that, to avoid incomplete interpretation, studies of thermal treatment on the breaking of physical seed dormancy should allow the seeds sufficient time to exhibit the complete effects of high temperature treatment, thereby preventing underestimation. [ABSTRACT FROM AUTHOR]

Members of the genus Atropa contain various tropane alkaloids, including atropine ((±)-hyoscyamine) and scopolamine, which possess medicinal properties. Preserving the diverse genetic background of wild populations via optimal plant production from seeds could be essential for avoiding the loss of potential uses. We analyzed the germination ecology of two Atropa species comprising the threatened A. baetica and widespread A. belladonna to determine the: (1) influence of temperature, light, and seed age on germination patterns; (2) effects of cold stratification and gibberellic acid (GA3); (3) phenology of seedling emergence in outdoor conditions; (4) phenology of dormancy break and loss of viability in buried seeds; and (5) ability to form persistent soil seed banks. Freshly matured seeds exhibited conditional physiological dormancy, with germination at high temperatures (32/18 °C) but not at low and cold ones (5, 15/4, 20/7 °C). The germination ability increased with time of dry storage and with GA3, thereby suggesting nondeep physiological dormancy. Under outdoor conditions, no seedlings emerged during the first post-sown autumn, but emergence peaks occurred in late winter–early spring. Both species could form small persistent soil seed banks with short durations (3–5 years). A plant production protocol from seeds was established for both taxa. [ABSTRACT FROM AUTHOR]

Persistent soil seed banks are a mechanism by which plant populations, especially those of pioneer species, replenish themselves after disturbance. Germination, and therefore aboveground replenishment, is linked to the abundance and vertical distribution of viable seeds in the soil, but it is unclear how different types of disturbance influence seed-bank structure. This distinction is critical for conservation, as anthropogenic sources increasingly alter the types of disturbance that ecosystems experience. We characterized the vertical structure of the seed banks of Paronychia chartacea (Papery Whitlow-wort) and Hypericum cumulicola (Highlands Scrub St. John's Wort), 2 federally endangered herbs endemic to Florida scrub, in habitats that experience fire (scrub habitat) and vehicle disturbance (roadsides). Within populations of each species in each habitat, we collected soil from 4 soil depths. We used microscopy and a germination study to measure total and viable seed density, then related these values to habitat, soil depth, and aboveground vegetation density. The vertical structure of viable seeds in the seed bank did not significantly differ between the 2 habitats. The top 4 centimeters of soil contained the majority of viable seeds for both species in both habitats, and viable seeds were denser in scrub habitat compared to roadsides. Roadsides contained relatively depauperate seed banks compared to natural, interior scrub. Abundance of viable seeds did not relate to aboveground vegetation density, possibly reflecting higher germination or recruitment on roadsides. This finding calls into question the long-term stability of apparently healthy roadside populations of endemic herbs, and necessitates further research into how seed banks influence the dynamics of these vulnerable species. [ABSTRACT FROM AUTHOR]

Premise: In 1879, Dr. William Beal buried 20 glass bottles filled with seeds and sand at a single site at Michigan State University. The goal of the experiment was to understand seed longevity in the soil, a topic of general importance in ecology, restoration, conservation, and agriculture, by periodically assaying germinability of these seeds over 100 years. The interval between germination assays has been extended and the experiment will now end after 221 years, in 2100. Methods: We dug up the 16th bottle in April 2021 and attempted to germinate the 141‐year‐old seeds it contained. We grew germinants to maturity and identified these to species by vegetative and reproductive phenotypes. For the first time in the history of this experiment, genomic DNA was sequenced to confirm species identities. Results: Twenty seeds germinated over the 244‐day assay. Eight germinated in the first 11 days. All 20 belonged to the Verbascum genus: Nineteen were V. blattaria according to phenotype and ITS2 genotype; and one had a hybrid V. blattaria × V. thapsus phenotype and ITS2 genotype. In total, 20/50 (40%) of the original Verbascum seeds in the bottle germinated in year 141. Conclusions: While most species in the Beal experiment lost all seed viability in the first 60 years, a high percentage of Verbascum seeds can still germinate after 141 years in the soil. Long‐term experiments such as this one are rare and invaluable for studying seed viability in natural soil conditions. [ABSTRACT FROM AUTHOR]

Seed banks are crucial regenerative resources for aboveground vegetation. The pattern of their changes holds immense significance in understanding alterations in the belowground seed bank. This understanding is pivotal for uncovering both short-term and long-term shifts in plant communities. Additionally, it contributes to the restoration of grassland ecosystems. To better protect grassland biodiversity and provide a theoretical basis for the restoration of degraded grasslands, in this study, the germination characteristics of soil seed banks in free-grazed, enclosed and mown areas were compared, and the results were combined with those of previous studies for a comprehensive analysis. The density of soil seed bank and perennial forage soil seed bank were significantly affected by different grassland utilization and soil depths. Grazing and enclosure grassland utilization methods increased the content of the soil seed bank, and mowing reduced the content of the seed bank. The soil seed bank density of perennial grasses accounted for the highest proportion under grazing, followed by mowing, and its lowest proportion was observed in the enclosures. Grazing not only facilitated the germination of the perennial grass seed bank but also substantially augmented its content. Mowing inhibited the germination of the upper growth grasses seed bank, which was particularly significant in the 0-2 cm soil layer under grazing. The content of the upper growth grasses seed bank affected the total seed bank to a certain extent, mainly in the 5-10 cm layer. The general correlations among the perennial grasses, upper growth grasses and soil germination seed bank resulted in 84.58% information extraction, and this information has practical significance for grassland ecological restoration. [ABSTRACT FROM AUTHOR]

Plant biodiversity data are prerequisites for the sustainable management of a forest. We used quantitative ecological tools to determine the species composition, diversity (richness and evenness), population structure, distribution patterns, and regeneration status of trees in a Tropical Moist Sal Forest of Eastern Ghats, India. For this purpose, a field inventory was conducted during 2020–2022 in sixteen 1.0 ha forest stands along a human-induced disturbance gradient. A total of 161 species (61 trees, 40 shrubs, 60 herbs) belonging to 77 families and 143 genera were recorded in the 16.0 ha of forest area. The results revealed a significant (p < 0.01) decrease in the tree and shrub species density, basal area, species richness, and diversity along the gradient of disturbance. However, in the case of herbs, the Shannon–Weiner diversity index increased significantly (p < 0.01) with increasing disturbance levels. Irrespective of forest types and disturbance levels, the tree diameter class (10–30 cm) accounted for the highest stem density in the forest. A mixed trend was found in the case of the basal area; the >41 cm diameter class constituted the highest basal area in the Pure Sal Forest while the 10–30 cm class was in the Moist Deciduous Forest without Sal. Tree species richness was found higher in lower diameter classes. Disturbances impacted the distribution pattern of trees; in the Pure Sal Forest, the contagious distribution of trees were 61.54%, 40%, and 12.5% in undisturbed, low-disturbed, and moderately disturbed sites, respectively. The percent of trees showing random and regular distribution increased with the increased level of disturbance in all forest types. The number of tree species having good regeneration decreased with the increased disturbance intensity in all forest types. Frequent grazing, repeated forest fires, and poor soil seed banks at the Moderately Disturbed site were the main reasons for the poor/no regeneration of Pterocarpus marsupium, Adina cordifolia, Terminalia bellerica, and some other economical species. Significant changes in structural attributes of the tree community revealed the impact of human-induced disturbances in the Moist Sal Forests of Eastern Ghats. The disturbance mosaics promoted the growth of many invasive weed species and lianas, depleting the number of valuable species in the forest. This study suggests the adaption of sustainable biodiversity conservation approaches through the active participation of the tribal so that the remnants the Moist Sal Forests of Eastern Ghats can be controlled to prevent further degradation. [ABSTRACT FROM AUTHOR]

Soil seed bank is the growth and reproduction source of vegetation community, playing an important role in vegetation establishment, succession and renewal, biodiversity maintenance. This study has selected the nascent wetland in the Yellow River Delta (YRD) formed in 1996 as study area and investigated the diversity and key influencing factors of soil seed bank diversity. The study results show that: (1) The soil seed bank in the study area has a simple structure, containing relatively few species. A total of five plant species, which belong to four families and five genera, were found in this bank, with Phragmites australis and Suaeda salsa being the dominant plants. (2) All species are herbs without woody species. One herb is annual herb and the others are perennial herbs. (3) From the sea to the river, the changes rules of the overall density and diversity of the seed bank are not obvious. (4) The dispersal distance from salt and freshwater has a significant influence on the density of the soil seed bank but has no significant influence on the diversity. Meanwhile, the soil salt content has a significant negative influence on the diversity of seed banks. (5) Aboveground vegetation did not closely relationship with diversity of soil seed bank. All above results can provide basic data and scientific evidence for the conservation of vegetation communities in the nascent wetlands and vegetation restoration in the degraded wetlands in the YRD. [ABSTRACT FROM AUTHOR]

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Introduced plants can have long-lasting and irreversible effects on the communities and ecosystems they invade. A critical step towards understanding the legacy of plant introductions is the characterisation of changes in the invaded plant communities and how these changes are related to biogeochemical modifications. Here, we addressed this issue by comparing the impacts of two large invasive herbs, Gunnera tinctoria and Impatiens glandulifera, on the compositional, functional, and phylogenetic structure of the standing vegetation (above-ground communities) and the soil seed bank (below-ground communities). The introduction of both invasive species was associated with a significant decrease in above-ground species richness, with subsequent changes in the functional diversity and phylogenetic dispersion of the vegetation. Yet, these invaders differed in their long-term impacts and the reversibility of any modifications they caused. While G. tinctoria invasions resulted in phylogenetically clustered communities (both above and below-ground) that were clearly distinct from uninvaded ones, seed bank communities invaded by I. glandulifera were indistinguishable from uninvaded ones, despite major compositional changes above-ground. Further, we found alterations in nutrient cycling associated with G. tinctoria invasions that could facilitate its local persistence and exacerbate any negative effects on native diversity. Our findings suggest a high susceptibility of pre-invasion above-ground communities to colonisation by distantly related herbs. However, the seed banks showed a degree of resilience against both invaders, with no major differences in species richness. Ultimately, differences in the impacts of these large invasive herbs suggest that dominance in the vegetation and a large stature are poor predictors of long-term plant community changes, including regeneration potential from seed, which are associated with plant introductions. [ABSTRACT FROM AUTHOR]

The exploitation of non‐timber forest products has been proposed as a sustainable way to exploit tropical forests, but such an opportunity remains to be proved. Here, we examine the impact of intensive açaí palm (Euterpe oleracea) management on the seed rain and soil seed bank in an estuarine forest landscape with a long history of forest management by locals in the Amazon region. Seed rain (100 80 cm2 collectors) and soil seed bank (100 30 cm2 samples) were monitored through a year across 20 forest stands, covering a gradient of açaí stem density (50–3575 açaí stems per ha). Seed rain and bank were dominated by açaí seeds (85.5%–85.8%) and by excluding them, seed rain and bank were low density and species poor, capturing a tiny subset from the local (17.91%–19.40%) and landscape woody flora (11.82%–14.55%). Moreover, autochthonous and vertebrated‐dispersed predominated as well as those from tree species considered useful by locals. Overall, açaí stem density positively affected açaí seed abundance in the seed rain and negatively affected seed pools in the bank in relation to abundance of seeds and vertebrated dispersed, while adult tree species richness and density and accessibility to forest stands were associated with more diversified seed pools. Thereby, forest stands are exposed to different levels of açaí management (high vs. low intensity) supported taxonomically distinct seed pools. Our results suggest that açaí intensification disturbs seed rain and soil seed bank with potential impacts on forest regeneration and the forest integrity standards required to consider açaí fruit production as sustainable according to current legislation. [ABSTRACT FROM AUTHOR]

Extensive green roofs are well known to improve the urban environment, but in the Mediterranean regions, dry climatic conditions pose the problem of their sustainability when no irrigation is applied. After planting or sowing in 2012, 18 local Mediterranean plant species on different types of exposure and substrate in a non-irrigated extensive green roof in Avignon (South-Eastern France), the physico-chemical characteristics of the soil, winter and spring soil seed banks, soil mesofauna and initially sown, planted, or spontaneous vegetation expressed on the surface were studied from 2013 to 2020. In 2020, significant differences related to the exposure conditions (shade/sun) and, to a lesser extent, to the depth of substrate used (5 cm/5 cm or 10 cm with a water retention layer) were found. The deeper plots in the shade have significantly higher soil fertility, cover, and vegetation height. However, the plots in the sun have higher moss cover, planted or sowed vegetation abundance, and springtail abundance. By 2020, more than half of the initially sown species had disappeared, except for several planted perennials and short-cycle annual species. On the other hand, a significant increase in the species richness of spontaneously established species was measured over time. In the absence of a permanent and transient seed bank for the sowed and spontaneous species, the plant community is then mostly dependent on species flows via the local surrounding seed rain. Planting perennial species (Sedum spp., Iris lutescens), followed by spontaneous colonization of species present in the vicinity of the roof would then represent a more efficient strategy for the persistence of extensive non-irrigated green roofs in Mediterranean environments than sowing a species-rich local Mediterranean seed mixture dominated by annual species. [ABSTRACT FROM AUTHOR]

South Busoga Central Forest Reserve, an isolated reserve in Uganda has been degraded for over forty years. To restore the reserve, the National Forestry Authority established plantations in some parts of the reserve and plans to reserve 40% under native vegetation. Until now, no study exists to inform management of the availability of native species in the degraded area to support natural forest regeneration. The objectives of this study were to: (i) establish if there are seeds of native forest species in the soil seed bank of plantations and unplanted areas (ii) assess the potential of the understory of plantations to serve as 'seed sources'. A seed bank assay of soils from plantations; Eucalyptus grandis, Maesopsis eminii and Pinus caribaea and unplanted areas was performed. Understory vegetation was sampled in 125 subplots of 5 × 5 m, randomly distributed in the plantations. In the seed bank, we recorded a total of 56 species in plantations and 22 in unplanted. There were more species in soils under E. grandis (12) > M. eminii (10) > P. caribaea (9) > unplanted area (3). Apart from Ficus sp. and Drypetes sp. that are woody, the rest of the species were non-woody. In the understory, we encountered a total of 56 species but only fifteen were native tree species with occurrence of less than five individuals each. These results show that sustained forest degradation depletes soil seed banks of native forest species and that plantations of exotic species can also nurse native species in their understory. [ABSTRACT FROM AUTHOR]

This study aimed to understand the impact of shrub encroachment on native species in the Guassa Community Conservation Area in Ethiopia. We assessed the soil seed bank composition and density across different elevations and aspects, and management systems within the area. The vegetation was stratified and eight blocks were selected across a range of elevation (<3350 m and >3350 m) and aspect (northeast, northwest, southeast, southwest). Within each block we established twenty 5m x 5m plots for a total of 160. We then collected soil samples from five subplots (1 m x 1 m) at three depths (0–3 cm, 3–6 cm and 6–9 cm) for a total of 480 samples, which were established in pots in greenhouse. We calculated species abundance by totaling the number of seedlings that emerged from each sample. To determine the variability in the abundance of Festuca macrophylla and Helichrysum splendidum in the soil seed bank along altitudinal gradient, we used two-way ANOVA using SAS statistical software version 9.0.1. Shannon diversity index was used to determine species diversity in the soil seedbank. After counting all the seeds, we identified 74 plant species represented in the soil seedbank which belong to 55 genera and 23 families. Eleven species are endemic to Ethiopia. At the lower elevation range, the effects of aspect (P <0.0088) and soil depth (P <0.005) are not significant to determine the abundance of seeds of H. splendidum and F. macrophylla. But when the factors are segregated, both aspect and soil depth play a significant role (p<0.0001) regarding the abundance of the seeds of the competing species at lower elevation. At higher elevation, only the effect of soil depth is significant (P<0.0001) for determining the abundance of H. splendidum. Soil depth and aspect have no significant effects on soil seed bank abundance at this elevation. [ABSTRACT FROM AUTHOR]

Invasion by nonnative annual plants that form prolific seed banks, including Bromus tectorum L. (cheat- grass), throughout western North America is a major natural resource concern. Even with known economic and ecological implications, soil seed banks and their potential to impact ecological restoration in arid and semiarid ecosystems are poorly understood. Quantifying the regenerative potential of the soil seed bank--the living seeds in the soil profile and on the soil surface--can help natural resource managers make decisions to increase the likelihood of restoration success. We analyzed the germinable soil seed bank composition and distribution of a rangeland site in western Colorado that experienced a wildfire in 1994 and is dominated by cheatgrass. We collected soil seed bank samples from 118 points in a 100 x 110 m grid to a depth of 5 cm. Each sample was split by depth from 0 to 2 cm and from 2 to 5 cm. and the seed bank was quantified using greenhouse emergence methods. We found that seeds of native species were more dense and evenly distributed (3391 seeds • m-2) than seeds of nonnative species were (1880 seeds • m-2) in the 0-5 cm seed bank across the site. We also found that seeds of both native and nonnative species were concentrated in the 0-2 cm layer of the seed bank but that native and nonnative seeds were present in substantive densities in the 2-5 cm layer. These findings suggest that the soil seed bank of the site is resilient, and a targeted approach to specifically deplete the seed bank of nonnative annuals could facilitate restoration by the in situ native seed bank. [ABSTRACT FROM AUTHOR]

Weeds can have both positive and negative effects on agricultural environments. However, despite the growing interest in the ecology of weed communities in agricultural areas, a few studies have been carried out in the northern region of the Andes of Colombia, where urban and agricultural expansion have generated highly disturbed scenarios. The aim of this study was to analyze the diversity of vegetation and weed seed banks in three agricultural production systems and a forest ecosystem in the northern Andes of Colombia. Hill numbers were used to compare diversity, Beta diversity to assess changes in composition, and range—abundance–dominance curves at different sites. Likewise, indicator species were analyzed to find species associations to each system. The results revealed differences in the composition of weeds between the forest ecosystem and the agricultural production systems, with higher equitability in the forest ecosystem and higher dominance in agricultural systems. Significant differentiation was observed among the dominant species within each agricultural system, particularly highlighting those species considered pests due to their unique life history traits. These traits confer them with a greater advantage in the face of various anthropogenic selection pressures. These findings highlight the impact of anthropogenic disturbances on the ecological dynamics of weed communities in different ecosystems, which should be considered when planning integrated weed management techniques. [ABSTRACT FROM AUTHOR]

The development of resistance in Alopecurus myosuroides populations to different herbicide active ingredients in Europe exacerbates efforts toward its chemical control. In Europe, cinmethylin provides an additional mode of action for the control of A. myosuroides. The objective of this study was to evaluate three resistance weed management (RWM) strategies, including cinmethylin and other pre‐emergence herbicides, for the control of multiple herbicide–resistant A. myosuroides. The RWM strategies used in this study differed in the extent of preventive cultural practices (tillage, crop rotation, sowing date and stale seedbed). Two field trials were conducted at sites with ACCase‐ and ALS‐resistant A. myosuroides biotypes in Germany between 2017 and 2020. Cinmethylin was included in the herbicide regime for A. myosuroides control. The combination of initial inversion tillage, delayed sowing, crop rotation diversification, and stale seedbed reduced the density of A. myosuroides bup to 90% compared to a strategy with pre‐emergence herbicides used as main components in control. At both sites, the amount of viable A. myosuroides seeds in the soil seed bank was reduced by over 90% after a 3‐year trial period in plots with initial inversion tillage. Molecular analyses revealed that the omission of ACCase and ALS inhibitors did not reduce the proportion of resistant A. myosuroides biotypes. Long‐term control of resistant A. myosuroides must be based on a combination of cultural practices that reduce the soil seed bank and suppress the occurrence of A. myosuroides and the use of still‐effective active ingredients for preventing the renewed entry of seeds into the soil. [ABSTRACT FROM AUTHOR]

We aimed to investigate the reproduction-related traits of Vicia biennis L., an endangered and poorly known wetland species in its western marginal populations (in Hungary), and discuss the conservational and ecological implications. We measured the mass, viability, and physical dormancy of half-year-old seeds in five in-situ collected seed lots, while potential seed longevity (i.e., seed bank type) was estimated from repeatedly germinating subsamples from four ex-situ collected seed lots for 3–8 years. Plant survival, flowering, and seed production were studied in different light-, irrigation-, and competition conditions in a botanical garden experiment. We found that 1) half-year-old seeds have a high germination capacity (78–100%), 2) and high level of physical dormancy (72–100%) in all examined Hungarian populations, and 3) the seeds can preserve their germination capacity for more than five years, although their viability sharply decreases, probably falling below 10% within ten years, when they are stored at room temperature. The results of the botanical garden experiment suggested that 1) the species is annual, not biennial; 2) it shows strong sensitivity to precipitation and low competitiveness for water; and 3) it can produce hundreds of seeds even in suboptimal (dry or shady) conditions. Although the species was found to be well-adapted to a temporally heterogeneous environment, its future vulnerability can increase depending on the duration of dry seasons. Further investigation of genetic diversity and soil seed bank is needed to estimate the actual vulnerability of the species while strengthening the populations through seed sowing, and additional vegetation control in the habitats is suggested. [ABSTRACT FROM AUTHOR]

Rare species threatened by climate and land-use change may harbor seeds in soil seed banks for periods of time even if adults have disappeared from the site. Soil samples were collected from sites with current Physostegia correllii populations and from sites with former populations in Lady Bird Lake (a reservoir of the Colorado River, Austin, Texas. A seedling emergence study was conducted under greenhouse conditions, and the presence/absence of seedling emergence was recorded for two years. Seeds germinated from the seed banks of all current and former colonies tested. The presence of seed banks in a historical site (Blunn Creek) of Physostegia correllii suggests that management to encourage the germination of seeds might help to encourage the establishment of populations of this species. The re-establishment of disturbance fugitives might be facilitated by removing overhanging ground vegetation or imposing water management regimes that mimic natural floodplain dynamics. [ABSTRACT FROM AUTHOR]

Non-ionic herbicides, such as propisochlor, are more easily retained in organic soil fractions. The presence of straw in tropical cropping systems can affect herbicide transposition to the underlying seed banks and their environmental behavior. The aim of this study was to evaluate propisochlor soil retention in the presence of soybean and sugarcane straw (0, 5 and 10 t ha−1) through radiometric techniques. Most of the applied 14C-propisochlor was retained in the soil profile (18.2–39.4%) following an extreme rainfall simulation in the presence of straw. Decreased herbicide leaching was observed in the presence of sugarcane and soybean straw (0.7–0.5%), compared with soil without straw (1.8%). Hysteresis values ranged from 0.8 to 1.0, indicating that propisochlor sorption was reversible allowing for soil seed bank effects, as well as environmental dissipation. These findings indicate that propisochlor can overcome straw barriers, although representing low groundwater contamination risks. Because of this, reduced environmental impacts following the application of this herbicide are noted for tropical cropping systems containing straw mulch. [ABSTRACT FROM AUTHOR]

Progressive habitat fragmentation threatens plant species with narrow habitat requirements. While local environmental conditions define population growth rates and recruitment success at the patch level, dispersal is critical for population viability at the landscape scale. Identifying the dynamics of plant meta-populations is often confounded by the uncertainty about soil-stored population compartments. We combined a landscape-scale assessment of an amphibious plant's population structure with measurements of dispersal complexity in time to track dispersal and putative shifts in functional connectivity. Using 13 microsatellite markers, we analyzed the genetic structure of extant Oenanthe aquatica populations and their soil seed banks in a kettle hole system to uncover hidden connectivity among populations in time and space. Considerable spatial genetic structure and isolation-by-distance suggest limited gene flow between sites. Spatial isolation and patch size showed minor effects on genetic diversity. Genetic similarity found among extant populations and their seed banks suggests increased local recruitment, despite some evidence of migration and recent colonization. Results indicate stepping-stone dispersal across adjacent populations. Among permanent and ephemeral demes the resulting meta-population demography could be determined by source-sink dynamics. Overall, these spatiotemporal connectivity patterns support mainland-island dynamics in our system, highlighting the importance of persistent seed banks as enduring sources of genetic diversity. [ABSTRACT FROM AUTHOR]

Anthropogenic nutrient enrichment and shifts in herbivory can lead to dramatic changes in the composition and diversity of aboveground plant communities. In turn, this can alter seed banks in the soil, which are cryptic reservoirs of plant diversity. Here, we use data from seven Nutrient Network grassland sites on four continents, encompassing a range of climatic and environmental conditions, to test the joint effects of fertilization and aboveground mammalian herbivory on seed banks and on the similarity between aboveground plant communities and seed banks. We find that fertilization decreases plant species richness and diversity in seed banks, and homogenizes composition between aboveground and seed bank communities. Fertilization increases seed bank abundance especially in the presence of herbivores, while this effect is smaller in the absence of herbivores. Our findings highlight that nutrient enrichment can weaken a diversity maintaining mechanism in grasslands, and that herbivory needs to be considered when assessing nutrient enrichment effects on seed bank abundance. Seed banks are reservoirs of plant diversity. This study shows that nutrient addition decreases diversity of grassland seed banks, increases their similarity to aboveground communities and interacts with aboveground herbivory to affect their abundance. [ABSTRACT FROM AUTHOR]

Aim: The soil seed bank is a key component of the biodiversity of plant communities, but various aspects of its functioning in temperate forest ecosystems are still unknown. We here adopted a trait‐based approach to investigate the effects of macro‐ and microclimatic gradients on the juvenile plant communities from the realized seed bank of two types of European temperate forest. Location: Oak‐dominated forests in Italy and Belgium. Methods: We analysed the variation of key functional traits (plant height, leaf area, leaf dry weight, specific leaf area and leaf number) of juvenile plants from the realised soil seed bank in relation to elevation (from 0 to 800 m a.s.l.), forest type (thinned and unthinned forest) and distance to the forest edge. We translocated soil samples from the forest core to the edge (and vice versa) and from high‐ to low‐elevation forests to test the effects of edge and warming respectively. Results: Taller communities developed at the forest edge due to higher light availability and warmer temperatures. The translocation from the core to the edge did not significantly modify mean trait values. Instead, the shadier and cooler microclimate of the forest core reduced the mean leaf area, mean dry weight, height and leaf number in the communities realised from the edge soil. The translocation from high‐ to lowland forests led to increased values for all traits (except specific leaf area). Edge vs core trait variation was more driven by intraspecific variability, whereas the translocation from high‐ to low‐elevation forests caused trait changes mostly due to species turnover. Conclusions: Global warming might result in a functional shift of the understorey due to both an early filtering effect on the seedlings from soil seed banks and their adaptive trait adjustments to temperature increase. Furthermore, our study underpins the importance of edge vs core microclimate in driving the functional composition of the realised soil seed bank. [ABSTRACT FROM AUTHOR]