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Dry evergreen Afromontane forests (DAF) once covered most of the Ethiopian highlands. Currently, they are found as a few patches. DAF restoration is a national forest restoration priority in Ethiopia. It has also been identified to be among global ecosystem restoration priorities. There are sufficient data to show DAF restoration from the soil seed bank or seed rain is hardly possible. Planting trees from multiple provenances is important to restore climate-resilient DAF. Therefore, DAF restoration cannot be achieved through natural regeneration alone and must be accomplished by planting characteristic DAF tree species. The poor soil moisture and nutrient conditions in Ethiopia's dry highlands result in low native tree seedling survival and growth. Hence, proper preparation of the planting sites and after-planting seedling care for at least two years is a reliable mechanism for achieving successful survival and growth. Along with seedling care after planting, four additional mechanisms discussed in this review (i.e. the use of nurse trees/shrubs, design of nursery practices, inoculation with arbuscular mycorrhizal fungi, and application of biochar) have also been shown to be useful. However, they cannot substitute for proper planting site preparation and post-planting seedling care. The complementary use of these five mechanisms could further enhance success. However, there are more questions than answers regarding the effectiveness of the five mechanisms discussed. We hope this review will motivate researchers to engage further to answer some of the important questions regarding restoration success. [ABSTRACT FROM AUTHOR]

The persistence of a soil seed bank influences weed management options. However, for many species, the degree of persistence of a soil seed bank is unknown. We assessed how long seeds remain in the soil for two invasive weeds, Chrysanthemoides monilifera subsp. monilifera (boneseed) and C. monilifera subsp. rotundata (bitou bush), as seeds of these species were predicted to have different longevity in the soil associated with differences in seed coat thickness. Seeds of both subspecies were buried at two depths at two sites in eastern Australia. Seeds were tested for germinability and viability regularly over an 8‐year period. Freshly collected seeds had quite low viability, and there was a rapid decline in viability in the first couple of years after burial, with C. m. rotundata declining faster than C. m. monilifera. Some seeds, however, remained viable in the soil at some sites for up to 8 years, with high site‐to‐site variability. The variability in viability from site to site may be due to the length of time soils remain moist: a combination of rainfall quantity and humidity levels. The low numbers of seeds remaining viable at 8 years indicate progressively lower probabilities of recruitment at sites following weed control but also suggest that monitoring for both subspecies needs to occur for a long period to minimize the risk of reinfestation from the seed bank. [ABSTRACT FROM AUTHOR]

Soil seedbanks are particularly important for the resiliency of species living in habitats threatened by climate change, such as alpine meadows. We investigated the germination rate and seedbank potential for the endemic species Dianthus pavonius, a carnation native to the Maritime Alps that is used as model system for disease in natural populations due to its frequent infections by a sterilizing anther-smut pathogen. We aimed to ascertain whether this species can create a persistent reserve of viable seeds in the soil which could impact coevolutionary dynamics. Over three years, we collected data from seeds sown in natural soil and analyzed their germination and viability. We found that D. pavonius seeds are not physiologically dormant and they are able to create a persistent soil seed bank that can store seeds in the soil for up to three years, but lower than the estimated plant lifespan. We conclude that while the seedbank may provide some demographic stability to the host population, its short duration is unlikely to strongly affect the host's ability to respond to selection from disease. Our findings have implications for the conservation of this alpine species and for understanding the evolutionary dynamics between the host and its pathogen. [ABSTRACT FROM AUTHOR]

This study investigates within-site variation in the diversity and composition of aboveground vegetation and seed bank in intensively managed wet grasslands of north-western Germany, comparing field edges, field margins and field interiors. We tested the hypothesis that unfertilized buffer strips at field edges function as refugia of characteristic species even in grasslands that are managed intensively for silage production. In 55 grassland sites on each marsh and moor soils, respectively, we conducted vegetation surveys, seed bank analyses and soil chemical measurements in field edge, margin and interior plots, and searched for the factors causing within-site variation in vegetation composition. The total species pool was small at the 110 sites, i.e. 148 species in the aboveground vegetation and 107 species in the seed bank, demonstrating severe impoverishment. The α-diversity decreased from 23 species (median) per 200 m2 at the edge to 15 species in the interior, with 38 species occurring only at field edges. The number of species with conservation value was very low in aboveground vegetation and seed bank and was only slightly higher at the edge than in the interior. Soil P availability was ca. 30% lower at the unfertilized edges than in the interior. We conclude that unfertilized buffer strips at grassland edges may help reducing nutrient leaching from high-input grassland systems, but they have mostly lost their refugial function for phytodiversity after decades of intensive management. Restoration efforts with seed or green hay transfer from richer source habitats are needed to promote biodiversity in field-edge buffer strips. [ABSTRACT FROM AUTHOR]

BACKGROUND: Striga hermonthica, an obligate root parasitic weed, poses a significant threat to cereal production in sub‐Saharan Africa. Lowering Striga seed bank in infested soils is a promising strategy to mitigate infestation levels. The dependency of Striga seed germination on strigolactones opens up the possibility of a 'suicidal germination' approach, where synthetic germination stimulants induce lethal germination in the absence of a host. Implementing this approach requires active germination stimulants with a suitable formulation for field application. Here, we describe the development of slow‐releasing granular formulation of two potent germination stimulants 'Methyl Phenlactonoate 3' and 'Nijmegen‐1' and the assessment of their activity under Laboratory, greenhouse, mini‐field, and field conditions. RESULTS: Under laboratory conditions, the granular formulation of either of the two germination stimulants (1.25 mg per plate, corresponding to 0.09 mg a.i.) induced Striga seed germination at a rate of up to 43%. With 10 mg granular product (0.75 mg a.i.) per pot, we observed 77–83% reduction in Striga emergence under greenhouse pot conditions. Application of the formulated stimulants under artificially or naturally infested fields resulted in approximately 56%, 60%, and 72% reduction in Striga emergence in maize, sorghum, and millet fields in Kenya and Burkina Faso, respectively. CONCLUSION: Our findings on the newly designed granular formulation of Methyl Phenlactonoate 3 and Nijmegen‐1 reveal encouraging prospects for addressing the Striga problem in Africa. These findings underscore several significant advantages of the formulated stimulants, including suitability for the African agricultural context, and, most importantly, their effectiveness in reducing Striga infection. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Phytogenic mounds are a type of microtopography formed under perennial plants canopies in water erosion areas. However, the function of phytogenic mounds in seed assemblages and their ecological consequences remain poorly understood in semiarid areas with water erosion. Thus, understanding the characteristics of seed banks on mounds is crucial for ecosystem conservation and management in water-eroded areas. Methods: We compared the quantity and composition of soil seed banks on the upslope and downslope parts of mounds and intercanopy surfaces along four slope gradients. We also explored the relationships among the soil seed bank, aboveground vegetation, and environmental factors. Furthermore, the species similarity between the soil seed bank and aboveground vegetation was analyzed to clarify the important ecological consequences of phytogenic mounds for plant community construction in serious soil erosion area. Results: For slopes with a = 46.6%, the intercanopy surfaces had greater soil seed bank species composition, density, and diversity than did the phytogenic mounds, and these characteristics showed no significant differences between the upslope and downslope parts of the mounds. As the slope increased, the soil seed bank density and species composition increased on the upslope part of the mound, and reached a maximum for slopes with a > 70%, while the downslope part of the mound negatively effected on seed aggregation. The sediment accumulation rate, soil moisture, particle size distribution, pH, organic matter carbon, and hardness were significantly correlated with the soil seed bank density and diversity in the study area. For slopes with 0 < a = 26.8%, the species similarity coefficient between the soil seed bank and aboveground vegetation was the highest for the intercanopy surface. This species similarity on the upslope part of the mound showed an increasing trend with increasing slope gradient, while the downslope part of the mound had the opposite trend. For slopes with a > 70%, the upslope part of the mound did not only have more species in the soil seed bank but also had more species in aboveground vegetation than did the downslope part of the mound and intercanopy surface. Conclusion: For slopes with a = 46.6%, phytogenic mounds had barely impact soil seed bank accumulation and conservation in semiarid and eroded areas. For slopes with a > 46.6%, the mounds (particularly on the upslope part of the mound) showed seed assemblage functions, which are coupled with improving edaphic conditions and decreasing microhabitat stress; thus, phytogenic mounds, or areas of microtopography, can be used to promote restoration success in semiarid eroded areas. [ABSTRACT FROM AUTHOR]

The soil seed bank (SSB) and soil microbial communities are among the most crucial drivers of belowground biodiversity in grasslands. Changes in components of soil biodiversity following protection from grazing were observed in cold, semiarid grasslands. To study these changes, soil samples were taken in an intensively grazed area and in an exclosure established 20 years prior to this study. In particular, changes in biodiversity components such as SSB and microbial activities in two soil depths (0–5 and 5–10 cm) were measured. Nonmetric dimensional scaling showed that after grazing removal, the SSB had changed. SSB density, richness, and diversity were higher in the ungrazed plots. The increase in SSB density and diversity in the exclosure may have been caused by the absence of direct adverse effects of grazing on the SSB, like trampling and plant consumption, or by reduced indirect effects, such as seed germination facilitation in canopy gaps created by grazing animals. The effect of grazing removal on basal respiration, substrate‐induced respiration, and urease activity was highly significant (p < 0.01) and may be due to an increase in soil moisture after grazing exclusion. The effect of grazing removal on soil biological parameters was greater in the upper layer than in the deeper soil layer. This study shows that grazing exclusion can be a useful approach in restoring components of soil biodiversity. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that the number of seedlings from the soil seed bank (SSB) in forests polluted by heavy metals and disturbed by recent fires decreases. It was also assumed that the consequences of pollution and fires for the soil seed bank are additive. We estimated the number of seedlings from the SSB of pine forests located near the Karabash copper smelter (KCS) (contaminated by Cu, Zn, Pb, and Cd) and from uncontaminated forests of the Ilmen State Reserve (ISR). In both areas, samples of the forest litter and humus horizon were taken from forests recently exposed to ground fires and long-term unburned forests. Samples were exhibited from June to September, conducting seven rounds of counting seedlings. Small peculiarities of the emergence of seedlings on the samples of the forest litter and the humus horizon were established. However, the regularities of the reaction of SSB to pollution and fire disturbances did not depend on the soil horizon. The number of seedlings on substrates from contaminated forests was 5–8 times lower than the number of seedlings on substrates from background forests. A decrease in the number of seedlings on polluted substrates was accompanied by an increase in the share of dicots in the total number of seedlings. The relationship between the number of seedlings and the age of fires was not found. The additivity of the consequences of pollution and fires has also not been established. Of the two types of damage, pollution and fires, the pollution factor is of leading importance for SSBs. The results indicate a low recovery capacity of the herb-shrub layer of polluted forests. [ABSTRACT FROM AUTHOR]

Survival in the soil seed bank is critical to a weed maintaining populations in arable lands. The role of the seed‐borne fungi in seed decay or survival needs to be determined to find solutions for reducing the weed seed banks in environmentally friendly ways. In this study, changes of the fungal microbiome after seed burial were determined in two economically important weed species, wild oat and barnyard grass. Seeds collected in different populations were buried in two sites and exhumed at intervals over the period of 1.5 years to test the seed fate. Epiphytic and endophytic fungal microbiota of seeds was characterised using both culture‐based approach and NGS of ITS1 region. The proportion of visually intact seeds and decayed seeds was different between the two burial sites. The observed species richness of the isolated epiphytic fungi was higher in the fresh compared to the buried seeds. Fungal taxa determined by NGS amplicon sequencing only partly coincided with the isolated fungi, revealing higher diversity in buried seeds. The dynamic of taxonomic structure of the fungal community was less pronounced in wild oat seeds compared to the barnyard grass seeds, where both endophytic and epiphytic communities were significantly different in the buried seeds and differed between the burial sites. It can be concluded that the epiphytic fungal communities change after seed burial in both plant species, while endophytic communities are more stable in the intact seeds and changes of the fungal community in the seed endosphere may be associated with seed decay. [ABSTRACT FROM AUTHOR]

Background: Understanding the reproductive biology of weeds is crucial for managing them effectively. Diplachne fusca (Poaceae) is a widely distributed weed species that poses significant challenges to agricultural productivity. Nevertheless, it remains unclear how the soil seed bank of D. fusca responds to environmental shifts, and whether a dormancy cycle is present in this species. Methods: We investigated how seed dormancy in D. fusca is broken and how it responds to natural environmental changes. The impact of incubation temperature, light exposure, cold stratification at 4 °C, and gibberellic acid (GA3) on seed germination/dormancy-break was investigated, along with assessing seasonal changes in germinability through monthly excavation and laboratory incubation of buried seeds over 2 years. Results: Results indicated that newly ripened seeds of D. fusca were dormant, with germination facilitated by GA3, cold stratification, and after-ripening at ambient room conditions. Exposure to darkness inhibited germination. Seasonal patterns of germination were observed, with peak germination occurring in cooler months and a marked decline during the hot summer months. After 2 years of being buried, approximately 40% of the seeds remained viable. Conclusion: In summary, seeds of D. fusca exhibit non-deep physiological dormancy and maintain a persistent soil seed bank. Seeds buried in the soil undergo a yearly dormancy/non-dormancy cycle. This dormancy cycle prevents seed germination and seedling emergence in autumn, which boosts the survival of seedlings in less favorable seasons, yet it also makes it more challenging to eradicate this weed. [ABSTRACT FROM AUTHOR]

The ecosystems across the world are affected by diverse impacts of climate change. Climate change will also affect soil seed bank as the seed bank is determined by the plants that are above the ground. This study was conducted to determine whether rainfall interception and resting period will affect the soil seed bank or not. Rainfall interception was employed as main plot treatment at four different levels--namely, 15%, 30%, 60%, and 0%--and the main plot treatments were each replicated five times using the rainout shelters arranged as main plot treatments in a split-plot experimental design. The main plots are 49 m² (7 m × 7 m) in size and were covered by metal frame structures with Vshaped clear acrylic bands on top without ultraviolet filter, and these plots were sub-divided into two sub-plots to determine the effect of resting periods (70 and 90 days). The soil samples were 8 cmin diameter and 20 cm in depth (1,005 cm³). We used seed emergence method rather than seed separation method to determine the soil seed bank due to the very small size of some seeds for some species. The 60% rainfall interception resulted in significantly high forb densities at both resting periods. The forb densities decreased by 32 and 35% at 15% and 30%, while they increased by 195% at 60% rainfall interception compared to 0% rainfall interception at 70-day resting period. Resting period significantly affected grass densities at 60% rainfall as the densities were higher at 70-than 90-day resting period. At 90-day resting period, grass densities were significantly higher at 0% rainfall interception than the rest of the treatments, while the grass densities were significantly lower at 60% rainfall interception. The 60% rainfall interception resulted in significantly (p< 0.05) higher total densities (forbs and grass) in both resting periods. Total density increased by 2.9% and 143.48% at 15% and 60% rainfall interception, respectively. Our results show that drought has a negative effect on grass soil seed bank, while it improves the forbs soil seed bank. Furthermore, the resting period has no significant effects on soil seed bank in grasslands. [ABSTRACT FROM AUTHOR]

The rare and threatened Heliosciadium repens grows in moist grasslands and has a distinct life cycle. Plants reproduce both clonally, although ramets tend to be short‐lived, and sexually, with seeds that can form a persistent soil seed bank. The germination requirements of H. repens were investigated, yielding important information for its habitat management and conservation. We examined the soil seed bank in three populations and carried out germination experiments and embryo growth measurements with fresh seeds in laboratory, greenhouse and outdoor conditions. We also investigated the effects of storage and burial of seeds. H. repens formed a long‐term persistent (>6 years) soil seed bank with very pronounced primary dormancy, but no secondary dormancy or dormancy cycles. Seeds can germinate throughout the growing season when temperatures are sufficiently high. Embryo growth and seed germination are triggered by light and, to a lesser extent, daily temperature fluctuations. Seeds of H. repens seem to have developed a unique germination syndrome with several strategies to remain dormant in the soil until optimal conditions are present for seedling establishment and survival. Both sexual reproduction and seed bank formation are crucial for the long‐term survival of the populations. [ABSTRACT FROM AUTHOR]

Aims: Changes in precipitation patterns, such as the predicted increases in the frequency of climatic extremes, are likely to alter plant communities, but whether responses to drought or to wetter conditions respectively cause consistent, opposite responses is debated. Here, we assessed the response in biomass production and species diversity of water‐limited plant communities to the direction (increase or decrease) and magnitude (micro‐ and macro‐climatic effects) of changes in soil moisture. Location: We reciprocally translocated soils containing seed banks from two climates (semi‐arid and mediterranean) at a micro‐climatic (opposite slopes) and a macro‐climatic scale (between climates) in Chile. Results: Biomass production for the soils that were translocated from wetter to drier climates was unrelated to the available soil moisture. The lowest biomass was produced in the wettest climate on the wet slope. Biomass production increased after a translocation to the drier climate (representing the largest change in climate). Nonetheless, the highest overall biomass for the wet to dry translocation was produced on the mediterranean dry slope with intermediate soil moisture. However, on the same mediterranean dry slope, biomass was almost zero for soil translocated the other way round (from drier to wetter). Diversity after 24 months was unaffected by micro‐climatic change, but soils transplanted toward the drier climate yielded a plant community with increased diversity. Conclusion: Our results showed direction and magnitude of climate change but also the response factor that is studied matters to detect direction‐dependent responses; i.e., species richness had a linear and reversible response. However, the response of biomass depended on the origin of the transplanted material (soil and plant community), indicating history dependence (hysteresis). This emphasizes that responses to unidirectional climate manipulation experiments may not be able to capture the entire nature of the response of plant communities to climate change. [ABSTRACT FROM AUTHOR]

Long‐term studies are needed to monitor recovery following restoration, as it may take decades or even centuries, particularly in the case of Mediterranean dry grasslands, for communities to reach their former equilibrium before the degradation occurred. A multi‐component approach is also needed to evaluate restoration success and better understand the complex impacts of former restoration projects on present‐day ecological interactions and ecosystem functions. The objective of this study was to address the restoration of a Mediterranean grassland in southern France, 20 years after implementation. Particularly, we examine the long‐term impact on soil, vegetation, and arthropods of the reintroduction of a dominant grass species (Brachypodium retusum) and the restoration of the natural stone cover on a degraded former cultivated field. Soil analyses revealed that reestablishing stone cover only slightly acidified the soil, while B. retusum presence enhanced soil fertility. Brachypodium retusum also decreased the nutritional value of forage and increased plant biomass and litter. Plant composition shifted with treatments: B. retusum and stone cover favored xeromesophilous species, while B. retusum alone encouraged less palatable species. The soil seed bank composition and abundance were positively influenced by stone cover but negatively impacted by B. retusum reintroduction. Negative outcomes on some arthropods and mesofauna were measured in treatments with both B. retusum and stones, except for Acari, which were positively impacted by the presence of stones. The findings emphasize that B. retusum is an ecological engineer with complex effects on the different ecosystem components. [ABSTRACT FROM AUTHOR]

Seed rain and the soil seed bank represent the dispersal of seeds in space and time, respectively, and can be important sources of recruitment of new individuals during plant community regeneration. However, the temporal dynamics of seed rain and the mechanisms by which the seed rain and soil seed bank may play a role in plant community regeneration with increased grazing disturbance remain unclear. Seed rain, soil seed bank, aboveground vegetation, and rodent density were sampled along a grazing gradient in an alpine marsh on the eastern Tibetan Plateau. We described the temporal dynamics of seed dispersal using Bayesian generalized mixed models, and nonmetric multidimensional scaling and the structural equation model were used to examine the effects of grazing disturbance on the relative role of seed rain and soil seed bank on aboveground plant community regeneration. The temporal dynamics of seed rain changed from a unimodal to a bimodal pattern with increased grazing disturbance. Both species diversity and seed density of the seed rain and seed bank increased significantly with increased grazing disturbance. Increased grazing disturbance indirectly increased the similarity of composition between seed rain, seed bank, and aboveground plant community by directly increasing species diversity and abundance of aboveground plant community. However, increased grazing disturbance also indirectly decreased the similarity of seed rain, soil seed bank, and aboveground plant community by directly increasing rodent density. The similarity between seed rain and aboveground plant community was greater than that of the soil seed bank and aboveground plant community with increased grazing disturbance. Grazing disturbance spreads the risk of seed germination and seedling establishment by changing the temporal dynamics of seed dispersal. Plants (positive) and rodents (negative) mediated the role of seed rain and soil seed bank in plant community regeneration. The role of seed rain in plant community regeneration is higher than the seed bank in disturbed alpine marshes. Our findings increase our understanding of the regeneration process of the plant community, and they provide valuable information for the conservation and restoration of alpine marsh ecosystems. [ABSTRACT FROM AUTHOR]

Soil seed bank contributes to the maintenance and renewal of the plant community. Species richness and density of the soil seed bank are affected by the temporal and spatial variations occurring in dry environments. Thus, this study aimed to characterize the effect of time (climatic season and annual precipitation) and space (soil depth and microhabitat type) on floristic composition, species richness, and seed density in the soil bank from a Brazilian dry forest over seven consecutive years. During the study period, 0–5 cm soil samples were collected in three types of microhabitats (Flat, Rocky, and Riverside) from the litter and soil, totaling 2940 samples. The seed bank was quantified using the seedling emergence method; each collected sample was monitored for six months. All data on species richness and seedling emergence were analyzed using the GLM and Anosim test for floristic composition. Results show that the floristic composition, species richness, and seed density differ between climatic seasons, between years of study, between soil depths, and between the three types of microhabitats found in the studied area. However, the explanatory power of each variable was low, demonstrating that other variables such as temperature, wind action, and predation may also be influencing seed storage in the soil bank. In summary, this study demonstrated that the richness, species composition, and emergence of seedlings recorded in soil seed banks are influenced by the spatiotemporal variation found in dry environments. Thus, all the tested variables partially explained the behavior observed in the seed bank. [ABSTRACT FROM AUTHOR]

There is some evidence that seed traits can affect the long-term persistence of seeds in the soil. However, findings on this topic have differed between systems. Here, we brought together a worldwide database of seed persistence data for 1474 species to test the generality of seed mass–shape–persistence relationships. We found a significant trend for low seed persistence to be associated with larger and less spherical seeds. However, the relationship varied across different clades, growth forms and species ecological preferences. Specifically, relationships of seed mass–shape–persistence were more pronounced in Poales than in other order clades. Herbaceous species that tend to be found in sites with low soil sand content and precipitation have stronger relationships between seed shape and persistence than in sites with higher soil sand content and precipitation. For the woody plants, the relationship between persistence and seed morphology was stronger in sites with high soil sand content and low precipitation than in sites with low soil sand content and higher precipitation. Improving the ability to predict the soil seed bank formation process, including burial and persistence, could benefit the utilization of seed morphology–persistence relationships in management strategies for vegetation restoration and controlling species invasion across diverse vegetation types and environments. [ABSTRACT FROM AUTHOR]

Background and aims: The most substantial global land use change is the transformation of native ecosystems into agroecosystems, leading to loss of biodiversity and reduction of ecosystem services. Potentially, these degraded systems could be restored from their soil seed bank. Our aim was to assess species richness and density of the soil seed bank along a structural complexity gradient in agroecosystems and Espinal forest fragments. Furthermore, we compared species composition between the soil seed bank and established vegetation of the reference system to explore its potential for regeneration of native plant communities. M&M: A structural complexity gradient was created from vegetation and soil structural variables from plots with different land uses to analyze seed bank variables. Results: The highest richness was recorded in the pasture soil seed bank, followed by the forests. The highest density and similarity to the established vegetation of the reference system was registered in the forests. Herbaceous species predominated in all plots. With the exception of Celtis tala, seeds of dominant woody species from the reference system were not observed. Conclusions: The pasture seed bank may be particularly relevant in the early stage of native forest restoration, especially if the aim is to reduce costs. However, the contribution of the seed bank to Espinal forests recovery in short to medium term is limited due to its low similarity to reference system. [ABSTRACT FROM AUTHOR]

Eucalyptus species are cultivated for various purposes around the world, mainly because they adapt well and grow quickly. These productive matrices of planted forests are common in Brazil, added to which, areas of native vegetation are requirements of environmental legislation. Although eucalyptus plantations are widely distributed in Brazil, little is known about the soil seed bank (SSB) in the eucalyptus productive matrix (EPM). We aim to understand how the EPM made up of eucalyptus plantations and native forest remnants affect the SSB in the Brazilian Pampa. Samples of the SSB of EPM were collected and monitored for 6 months in a shade house. We evaluated seedling emergence, richness, composition, ecological characteristics of the species, diversity, and floristic similarity. We recorded a high rate of seedling emergence, species richness, and different life forms and native species in all EPM treatments; however, the similarity between native remnants and eucalyptus plantations was low. The size and level of conservation of native remnants and the position and management of eucalyptus sites in the EPM influenced the diversity and composition of species. Eucalyptus plantations contain SSBs with potential for natural regeneration when they are in a landscape that maintains conserved native forest remnants. These results expand the knowledge of the SSB in EPM and can support actions in ecological restoration projects. [ABSTRACT FROM AUTHOR]

The aim of the present review is to compile and analyze information on biology of Rhinanthus species in the context of grassland biodiversity. Root hemiparasites have been relatively less studied in comparison to economically important holoparasitic weed species. Rhinanthus species appear to be genetically polymorphic, but also possess high phenotypic plasticity, and ecological factors are important determinants in evolution of specialization to most appropriate hosts. Rhinanthus individuals have a relatively short life span, and flowering is a photoperiod- or host plant-independent phenomenon. Both insect pollination and self-pollination can occur. Seeds do not form a persistent soil seed bank and have physiological dormancy broken by stratification. In general, Rhinanthus species have low host specificity, but there clearly are 'preferred' or 'avoided' hosts in natural conditions. In controlled conditions, interaction with most grass species result in more prominent parasite growth stimulation in comparison to that of legumes, and, especially, forbs, but there are significant gradations and exceptions. Ecological requirements of Rhinanthus species have been rarely studied, but it can be expected that significant tolerance against mineral nutrient heterogeneity and water shortage can be found. It seems that host plant characteristics are important determinants of the environmental resilience of Rhinanthus. Parasites not only obtain resources (water and minerals) from host plants but also negatively affect their physiological functions. The most intriguing and practically unexplored question is the exchange of chemical signals between the Rhinanthus parasite and the host plant. Extending this idea, it can be predicted that signals will also be exchanged between multiple host plants whose roots are connected through the parasite. It is highly possible that the exchange of small RNAs between plants could influence their environmental tolerance. Host selectivity forms the functional basis of changes in species diversity in grasslands, but the outcome seems to be highly dependent on other conditions, especially, soil edaphic factors. Development of new model systems is necessary to further expand our knowledge about the complex effects of parasitic plants on ecosystems. [ABSTRACT FROM AUTHOR]

Seeds maintained on seed banks are submitted to two conditions of light during discontinuous hydration: presence or absence. We aimed to investigate the influence of light during discontinuous hydration and its relationship with the establishment of the cacti species. We raised two hypotheses: discontinuous hydration increases the longevity of seeds, and the presence and the absence of light during hydration/dehydration cycles (HD cycles) present different benefits in maintaining their viability in the soil seed bank for a longer time. We subjected seeds to HD cycles in the presence and absence of light. After that, we established a soil seed bank and analyzed the germinative behavior and biochemical compounds at intervals of 0, 3, 6, 9, 12, and 15 months. HD cycles prolonged seed longevity, confirming our first hypothesis. Treatments of HD cycles in the darkness provided the maintenance of seed viability for a period longer than 9 months, which corroborates our second hypothesis. HD cycles in the presence of light only favor the germination behavior of fresh seeds. Reducing sugars are consumed during the first months in seeds buried in the soil. However, protein concentration remains higher in seeds not submitted to HD cycles after 12 months. Our study proposes the existence of a "seed dark hydration memory" related to seed longevity and a "seed light hydration memory" related to the germination of fresh seeds. Thus, the response to light incidence during discontinuous hydration represents an important strategy for the reproductive success of positive photoblastic species in their natural environment. [ABSTRACT FROM AUTHOR]

Biochar is a widely proposed solution for improving degraded soil in coastal wetland ecosystems. However, the impacts of biochar addition on the soil and plant communities in the wetland remains largely unknown. In this study, we conducted a greenhouse experiment using soil seed bank from a coastal salinealkaline wetland. Three types of biochar, including Juglans regia biochar (JBC), Spartina alterniflora biochar (SBC) and Flaveria bidentis biochar (FBC), were added to the saline-alkaline soil at ratios of 1%, 3% and 5% (w/w). Our findings revealed that biochar addition significantly increased soil pH, and increased available potassium (AK) by 3.74% - 170.91%, while reduced soil salinity (expect for 3% SBC and 5%SBC) by 28.08% - 46.93%. Among the different biochar types, the application of 5% FBC was found to be the most effective in increasing nutrients and reducing salinity. Furthermore, biochar addition generally resulted in a decrease of 7.27% - 90.94% in species abundance, 17.26% - 61.21% in community height, 12.28% - 56.42% in stem diameter, 55.34% - 90.11% in total biomass and 29.22% - 78.55% in root tissue density (RTD). In particular, such negative effects was the worst in the SBC samples. However, 3% and 5% SBC increased specific root length (SRL) by 177.89% and 265.65%, and specific root surface area (SRSA) by 477.02% and 286.57%, respectively. The findings suggested that the plant community performance was primarily affected by soil pH, salinity and nutrients levels. Furthermore, biochar addition also influenced species diversity and functional diversity, ultimately affecting ecosystem stability. Therefore, it is important to consider the negative findings indirectly indicate the ecological risks associated with biochar addition in coastal salt-alkaline soils. Furthermore, Spartina alterniflora was needed to desalt before carbonization to prevent soil salinization when using S. alterniflora biochar, as it is a halophyte. [ABSTRACT FROM AUTHOR]

The soil seed bank is one of the most important ecological indicators to evaluate and monitor the ecological restoration process of plant communities. We aimed to analyze the influence of two different ecological restoration techniques on the diversity and floristic composition of the soil seed bank and of standing vegetation, in two 4‐year‐old areas under forest restoration around bauxite mining, Southeast Brazil. A total of 30 soil samples were collected in each area (SPN—forest restoration by seedling planting in rows and nucleation techniques between planting rows and SP—forest restoration by seedling planting in rows). The samples were transported to a shade house and evaluated for 6 months, where germinated individuals were counted and identified weekly. A floristic census of shrub/tree species was conducted to assess the diversity of standing vegetation. The results indicated that the soil seed banks of the two areas are floristically similar (predominance of pioneer, herbaceous, and native origin species). The two restoration techniques did not differ in their effects on the species composition of the soil seed bank, mainly due to the restoration age. However, when analyzing the standing vegetation, 38 species were recorded in SPN, while only 20 species were in SP. This result demonstrates that nucleation techniques contributed to the increase in species diversity in SPN. We conclude that combining seedling planting in rows with nucleation techniques (topsoil transposition, direct seeding, and artificial perches) can enhance species diversity in standing vegetation, improve forest functionality, and consequently enhance the potential for forest restoration. [ABSTRACT FROM AUTHOR]

Soil seed banks help maintain species diversity through temporal storage effects and function as germination pools that can optimize fitness across varying environmental conditions. These characteristics promote the persistence of native plant communities, yet disturbances such as fire and associated invasions by non-native species can disrupt these reserves, fundamentally altering successional trajectories. This may be particularly true in deserts, where native plant communities are less adapted to fire. While studies of fire effects on desert plant communities are not uncommon, information regarding the short- and long- term effects of fire on seed banks is less available. To better understand the influence of fire and invasive species on desert seed banks, we investigated soil seed bank biodiversity from 30 wildfires that burned between 1972 and 2010 across the Mojave Desert ecoregion of North America. We assessed how characteristics of fire regimes (frequency, time since fire, and burn severity) interacted with climate and invasive plants on measures of a-, p-, and g- diversities. Because p-diversity is a direct measure of community variability and reveals important information about biodiversity loss, we further examined the nestedness and turnover components of p-diversity. Mean a- and ^-diversities were generally higher for burned locations than in unburned reference sites, however individual fire variables had little influence on patterns of seed bank diversity. Burned area seed banks tended to be dominated by non-native invasive species, primarily two grasses, (Bromus rubens, Bromus tectorum), as well as an invasive forb (Erodium cicutarium). The most striking pattern we observed was a collective sharp decline in a-, p-, and g-diversities with increased invasive species dominance, indicating the homogenization of seed bank communities with the colonization of invasive species after fire. Evidence of homogenization was further supported by reduced turnover and increased nestedness in burn areas compared to reference areas indicating potential biodiversity loss. Our findings highlight how biological processes such as plant invasions can combine with disturbance from fire to alter patterns of seed bank composition and diversity in desert ecosystems. [ABSTRACT FROM AUTHOR]

Bassia dasyphylla is a prevalent herbaceous plant that exhibits enhanced resilience to dryness and elevated temperatures. It is frequently found in dispersed or grouped formation on sandy soil within steppe, semi-desert, and desert regions. Herein, we conducted experiments to examine the growth and physiological traits of B. dasyphylla seeds originated from various regions in response to water scarcity. The study seeks to investigate the ability of these seeds to germinate under drought conditions and offer valuable insights for the development and breeding of high-quality germplasm resources in Inner Mongolia. The results demonstrated that B. dasyphylla originating from desert steppe (DS) exhibited a greater capacity to endure drought conditions in comparison to its counterparts from sandy land (SL). At a water potential of -0.30 MPa, the Seed germination rate from DS was 33.3%, while from SL it was 22.7%. With the increase in drought duration and intensity, germination rate, plumule length, both single-seed weight (SSW) and seed water content (SWC) of B. dasyphylla declined. The protective enzyme activity exhibited an initial increase, followed by a subsequent decline as the duration of the drought increased. Notably, we found that the protective enzyme activity from DS was higher than that from SL. During the initial and intermediate stages of dryness, the soluble sugar and protein of the plant from DS effectively inhibited the peroxidation of membrane lipids, whereas the osmoregulatory properties from SL did not have a significant impact. The findings suggest that the ability of B. dasyphylla to withstand drought conditions in DS can be attributed to its elevated amounts of protective enzymes and osmoregulatory factors, which serve to safeguard the cell membrane during periods of drought. [ABSTRACT FROM AUTHOR]

Environmental factors, such as temperature and moisture, and plant factors, such as seed position on the mother plant, can affect seed viability and germination. However, little is known about the viability and germination of seeds in different positions on the mother plant after burial in soil under natural environmental conditions. Here, diaspores from three positions on a compound spike and seeds from two/three positions in a diaspore of the invasive diaspore‐heteromorphic annual grass Aegilops tauschii were buried at four depths for more than 2 years (1–26 months) under natural conditions and viability and germination monitored monthly. Viability of seeds in each diaspore/seed position decreased as burial depth and duration increased and was associated with changes in soil temperature and moisture. Germination was highest at 2 cm and lowest at 10 cm soil depths, with peaks and valleys in autumn/spring and winter/summer, respectively. Overall, seeds in distal diaspore and distal seed positions had higher germination percentages than those in basal diaspore and basal seed positions, but basal ones lived longer than distal ones. Chemical content of fresh diaspores/seeds was related to diaspore/seed position effects on seed germination and viability during burial. We conclude that seeds in distal diaspores/seed positions have a 'high risk' strategy and those in basal positions a 'low risk' strategy. The two risk strategies may act as a bet‐hedging strategy that spreads risks of germination failure in the soil seed bank over time, thereby facilitating the survival and invasiveness of A. tauschii. [ABSTRACT FROM AUTHOR]

Questions: Free‐ranging herbivores are often seen as important endozoochorous dispersal vectors for plant propagules. Dispersal by free‐ranging animals, in contrast to domestic animals, and its effects on vegetation have rarely been studied. We ask what are the effects of deposition of dung on open landscape vegetation, how does it influence vegetation development after disturbance by soil removal, and does it change species richness or composition? Location: The Doupov Mountains, Czech Republic. Methods: We established a six‐year experiment in 2015 to study the effects of dung deposition on vegetation of an open grassland landscape. The experiment comprised 300 plots distributed across five fenced site locations and treatments were implemented in partially crossed design, with soil removed (disturbance) and dung pellets deposited; treatments were applied once to five replicates, from June to October 2015. We recorded plant species cover at the beginning of the vegetation seasons of 2016, 2017 and 2021. Results: Dung deposition increased species richness and Ellenberg Indicator Values for nutrients, and these effects were stronger in disturbed plots; however, these effects diminished with time. There were no effects of dung deposition on species composition. In contrast, disturbance affected species diversity, composition, Ellenberg Indicator Values for nutrients, proportion of dung‐dispersed species, but not species richness. Surprisingly, there were no effects of timing of dung deposition. Conclusions: Our results indicate that endozoochorous seed dispersal by red deer impacts vegetation dynamics of this open grassland landscape, but effects are weak and diminish with time. Considering the large seed load in dung, it is possible that endozoochorous seeds from wild herbivores are incorporated into the soil seed bank, where they persist until appropriate ecological conditions for germination arise. [ABSTRACT FROM AUTHOR]

Questions: Fire is an important ecological factor influencing plant communities in many fire‐prone ecosystems. Savannas in the Cerrado are resilient to fire, with plants exhibiting fire‐related traits, allowing them to persist in post‐fire environments. Therefore, excluding fire may result in changes in plant community dynamics, thus affecting their resilience. We investigated the effect of the reintroduction of fire in savannas where fire has been excluded for longer periods (>12 years) on seedling recruitment. We asked the following questions: (i) how does fire affect seed bank germination in sites with different fire histories; and (ii) how did fire exclusion affect species composition of the seed bank? Location: Estação Ecológica de Itirapina (EEI), Southeastern Brazil. Methods: Two sites with different fire histories were selected: FE1985 – fire exclusion for more than 30 years, with one fire event in 1985; and FE2009 – fire exclusion for 12 years, with three fire events since 1985, the last one being in 2009. Both areas have low fire frequency, but different times since the last fire. Soil samples were collected before and after prescribed fires to evaluate the effects of fire after longer periods of fire exclusion in the soil seed bank. Using the seedling emergence method, we evaluate the effects of the reintroduction of fire after longer periods of fire exclusion in the soil seed bank. Results: We found that fire significantly increased the seed bank recruitment at both sites, FE1985 and FE2009 (increase of 16% and 50% in seedling recruitment, respectively), showing that species of the Cerrado responded positively to the fire passage. The reintroduction of fire promoted different effects on seed bank recruitment: shrubs experienced a significant decrease in seedling emergence from the seed bank at FE1985, while their recruitment was not affected at FE2009. Time since last fire appears to influence the seed bank composition, showing a shift in dominance from a grassy community to a woody one. Conclusions: After fire, more species germinated from the seed bank, showing that direct and indirect effects of fire are affecting seed germination from the seed bank, and its importance on seedling recruitment from the seed bank in the Cerrado. [ABSTRACT FROM AUTHOR]

Natural regeneration after mining activities depends largely on the soil seed bank (SSB) and aboveground vegetation (AGV) richness and composition. We evaluated the species diversity pattern of the SSB and AGV on soil and technosol across second‐growth Atlantic Forests (SGFs) after mining tailings deposition in Mariana, southeastern Brazil. Two second‐growth Atlantic seasonal semideciduous forests of different stand ages were selected: a 3‐year‐old stand of SGF re‐growing on tailings (SGF tailings) and a 30‐year‐old stand of native reference forest not affected by tailings (SGF nontailings). Overall, the results showed significant differences in forest attributes (species richness and composition) in the SSB and AGV between the two forest patches evaluated (SGF tailings and SGF nontailings). Moreover, both nonzoochoric and zoochoric dispersed species of AGV showed significant differences between second‐growth forests, with higher variability of community‐weighted mean in SGF tailings. The result shows smaller differences in species richness between forest types for both SBB (ranging 85 and 90 species) and AGV (~55 species). Despite the time difference between the secondary forest and the absence of zoochoric species in the tailings seed bank, the AGV that are re‐growing on mining tailings presented a high proportion of zoochoric species. This pattern of species richness and community composition variability observed in the technosol seed bank, and AGV that are re‐growing after the deposition of mining tailings are important recovery indicators for plant communities affected. [ABSTRACT FROM AUTHOR]

The New Zealand bottlebrush, Metrosideros excelsa (Myrtaceae), was introduced into South Africa in the 1940s as an ornamental plant and subsequently naturalized in coastal parts of the Cape Floristic Region. Knowledge of M. excelsa's propagule pressure and response to fire in South Africa can inform evaluation of the species' invasion potential and management. We assessed M. excelsa's canopy and soil seed banks in burnt and unburnt stands; and post‐fire regeneration via reseeding and resprouting in relation to fire severity and tree size. Soil seed banks were assessed using an emergence technique, but no seedlings emerged from soil collected under burnt or unburnt plants suggesting that the species does not maintain a viable soil‐stored seed bank or germination triggers were not met (though unlikely). The annual seed crop in the canopies of unburnt trees was approximately 0.5–23 million seeds per tree. Viability, assessed through tetrazolium stain testing, of canopy‐borne seeds on unburnt trees was 18%, whereas a canopy fire, ranging in severity from low to extreme, killed all canopy‐borne seeds. Fifteen months post‐fire, the seedling to pre‐fire (live) tree ratio was 0.01, whereas 43% of burnt trees survived via basal resprouting. Fire severity had a non‐linear effect on tree survival (survival was highest after medium and high fire severity and lowest after low and extreme fire severity), while larger trees were more likely to survive fire. These results suggest that even low‐severity (safe) burning may be a useful control measure as it kills canopy‐borne seeds and causes substantial mortality, particularly of smaller trees. An opportunistic evaluation of an uncontrolled (no comparison with untreated individuals) foliar herbicide application to post‐fire resprouting individuals also showed considerable (91%) mortality. However, rigorous herbicide trials (also with herbicide in conjunction with burning) are required to inform the management of M. excelsa. [ABSTRACT FROM AUTHOR]

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Background: Hyptis suaveolens (L.) Poit., native to the American tropics, is a pantropical annual plant and a major invasive species throughout India. It was anticipated that the availability of sunlight, coupled with its superior reproductive potential, persistent propagule bank, and dispersal ability, could lead to an increase in the growth and spread of this invader, thus potentially impeding herbaceous growth and diversity in non-native areas. Clarifying its ecological fitness and competitive performance will be useful to manage the spread of H. suaveolens in natural ecosystems that are facing a wide range of anthropogenic pressures. Methods: The present study is a three-tier experiment. In the first tier, a field study was conducted to assess the patterns of H. suaveolens abundance and herbaceous species diversity in response to light availability (sun, 842–1072 µmol m–2 s−1 and shade 253–341 µmol m–2 s−1) in the tropical dry deciduous ecosystems in the Vindhyan highlands, India. Furthermore, the impact of H. suaveolens abundance on the resident native and non-native species abundance and diversity was also studied. In the second tier, a randomized common garden experiment was conducted to understand the trait fitness of H. suaveolens in sun (940 µmol m–2 s−1) and shade (300 µmol m–2 s−1) conditions. In the third tier, a plant growth chamber experiment with high-light (940 µmol m–2 s−1) and low-light (300 µmol m–2 s−1) treatments was done to learn how H. suaveolens partitions its biomass between aboveground and belowground plant parts. Results: The field study indicated that the sunlit areas had a higher abundance of H. suaveolens and a lower diversity of resident herbaceous species than the shaded areas. The common garden experiment showed that sun-dwelling H. suaveolens individuals performed better in germinative, vegetative, eco-physiological, and reproductive traits than the shade-dwelling individuals. The growth chamber experiment exhibited that plants grown in high-light environment had greater seed germination, seedling recruitment, and aboveground biomass than those grown in low-light environment, whereas plants grown in low-light environment exhibited a higher root mass ratio than the high-light individuals. These results suggest that H. suaveolens individuals mask the understory vegetation owing to higher seedling recruitment, relative growth rate, photosynthetic performance, resource acquisition-allocation, and reproductive output in response to high-light conditions. Conclusions: The study concludes that light significantly controls the invasive population dynamics of H. suaveolens in dry deciduous forests. In high-light areas, H. suaveolens populations dominate the forest understory with suboptimal shade tolerance. In shade environment, H. suaveolens maintains a persistent soil seed bank along with 'Oskar individuals' that become active in response to high-light availability. The modus operandi is a 'sit and wait' strategy. The current study provides insights on prioritizing areas for H. suaveolens management that will potentially reduce the risk of biological invasions on the native species diversity of tropical regions. [ABSTRACT FROM AUTHOR]

Many plant species are well-adapted to historical fire regimes. An increase in the severity, frequency, and extent of wildfires could compromise the regenerative capacity of species, resulting in permanent shifts in plant diversity. We surveyed extant vegetation and soil seed banks across two forest types with contrasting historical fire regimes—Shrubby Dry Forest (fire return interval: 10–20 years) and Sub-Alpine Woodland (50–100 years). Over the past 20 years, both forests have been subject to repeated, high-severity wildfires at intervals significantly shorter than their historical return intervals. We examined the soil seed bank response to fire-cued germination, and whether the plant diversity in soil seed banks and extant vegetation demonstrated similar responses to short-interval, high-severity wildfires. The soil seed bank demonstrated a positive response to heat in combination with smoke, and for the Sub-Alpine Woodland, this was limited to sites more frequently burnt by fire. With an increase in fire frequency, there was a decline in species richness and Shannon's Diversity and a shift in species composition in both extant vegetation and the soil seed bank. The fire frequency effects on the relative richness of trait associations were restricted to the Shrubby Dry Forest, and included an increase in short-lived obligate seeders, wind-dispersed species, and ant-dispersed shrubs in burnt relative to long unburnt sites in both extant vegetation and the soil seed bank. Graminoids were the most abundant component of the soil seed banks of Sub-Alpine Woodlands, and this increased with more frequent fire, with a similar trend (p = 0.06) in extant vegetation. Clear shifts in plant diversity in both soil seed banks and extant vegetation in forest types with contrasting historical fire regimes suggest that emerging fire regimes are pushing ecosystems beyond their historical range of variability, including potentially more flammable states and a decline in the buffering capacity of soil seed banks. [ABSTRACT FROM AUTHOR]

Background and aims: Soil seed bank plays a significant role in the natural recovery and the succession of forest. A large number of natural secondary forests are distributed in the Qining Mountains, China. However, it remains unclear how the soil seed banks develop and influence the recovery of secondary forests. Methods: We explored the aboveground vegetation and soil seed bank at 27 plots along forest developmental stages of pine and oak forests in the Qinling Mountains. Species composition and abundance of aboveground vegetation as well as seed bank composition and density were surveyed and their correlations with forest developmental stages were determined. Results: The results showed that the species richness of seed banks was the highest in middle-aged forests, as well as the aboveground vegetation. The seed density and abundance increased with forest developmental stages and varied among different forest types. The similarity between seed banks at different developmental stages of the same forest type was high, as well as aboveground vegetation. The seed bank and aboveground vegetation showed low similarity across the three developmental stages of both forest types, and the persistent soil seed bank did not reflect the changes in aboveground vegetation. Conclusion: Our findings demonstrate that developmental stages play an important role in the composition of seed banks and aboveground vegetation. Our results also highlight the persistent soil seed bank contributes less to the forest recovery. We can assume that the natural recovery of disturbed natural secondary forests is largely dependent on transient soil seed bank and seed dispersal. [ABSTRACT FROM AUTHOR]

The ongoing loss of red‐listed coastal heathlands is a threat to biodiversity and cultural heritage legacies throughout the Atlantic coastal regions of Europe. It is possible to restore degraded and afforested heathlands, but restoration interventions are often labour‐intensive and costly, and the outcome of specific restoration actions are not well documented. We assess the efficiency of restoring coastal heathlands through natural succession (i.e. 'passive restoration') after removal of Sitka spruce Picea sitchensis (Bong.) Carr. plantations. The study was replicated on two neighbouring islands in a nature reserve in Western Norway. Low‐intensity free‐range sheep grazing was implemented as part of the reserve management plan. Furthermore, we tested the effect of leaving the clear‐felled woody material as chips on site, this being a cost‐efficient strategy on islands. Succession was monitored 1, 2, 4/5 and 8 years after clear‐felling, and revegetation of vascular plants and bryophytes was compared to target heathland vegetation. Surprisingly, we found different successional trajectories on the two islands. Species composition on one island approached target heathland vegetation during succession, but not on the other. Wood chips reduced species richness and slowed the restoration process, but these negative effects were only short‐term (<8 years). Differences in seed bank composition and soil conditions due to land use may explain the deviating successional trajectories on the two islands. We also found that management actions beyond clear‐felling and introducing sheep grazing are necessary due to the rapid seed regeneration of the Sitka spruce. [ABSTRACT FROM AUTHOR]

Accumulated evidence indicates that species with small, rounded seeds predominantly maintain a persistent soil seed bank, while those having larger and less isodiametric seeds have a transient seed bank. We assumed that species in certain special habitats may be exceptions to this rule. In habitats with sandy soil and open vegetation, the seeds do not necessarily have to penetrate the deeper soil layers through cracks in the soil. Instead, the seeds can become buried by a windblown layer of sand, thus seed morphology does not really affect the burial process. To test our hypothesis, we selected five semi-desert shrubs and one perennial herb of open sandy grasslands, all of which had large and flattened seeds. For each species, 12 repetitions of 50 seeds were buried in the soil. Seeds were recovered after 3, 20 and 26 months of burial and subjected to germination tests. Seeds of each species germinated in all test occasions, with final germination as follows: Atriplex canescens 89.0%, Haloxylon ammodendron 11.5%, H. persicum 11.5%, Pteropyrum aucheri 43.5%, Xylosalsola richteri 12.0% and Asclepias syriaca 26.0%. The results confirm the hypothesis that each of the six species is capable of forming a persistent soil seed bank. The results also show that in habitats where seed burial can take place passively through windblown soil, plant species might bypass the tradeoff between seed size/shape and seed longevity. [ABSTRACT FROM AUTHOR]

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]