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Background and aims Seed heteromorphism is a plant strategy that an individual plant produces two or more distinct types of diaspores, which have diverse morphology, dispersal ability, ecological functions and different effects on plant life history traits. The aim of this study was to test the effects of seasonal soil salinity and burial depth on the dynamics of dormancy/germination and persistence/depletion of buried trimorphic diaspores of a desert annual halophyte Atriplex centralasiatica . Methods We investigated the effects of salinity and seasonal fluctuations of temperature on germination, recovery of germination and mortality of types A, B, C diaspores of A. centralasiatica in the laboratory and buried diaspores in situ at four soil salinities and three depths. Diaspores were collected monthly from the seedbank from December 2016 to November 2018, and the number of viable diaspores remaining (not depleted) and their germinability were determined. Results Non-dormant type A diaspores were depleted in the low salinity “window” in the first year. Dormant diaspore types B and C germinated to high percentages at 0.3 and 0.1 mol L -1 soil salinity, respectively. High salinity and shallow burial delayed depletion of diaspore types B and C. High salinity delayed depletion time of the three diaspore types and delayed dormancy release of types B and C diaspores from autumn to spring. Soil salinity modified the response of diaspores in the seedbank by delaying seed dormancy release in autum and winter and by providing a low-salt concentration window for germination of non-dormant diaspores in spring and early summer. Conclusions Buried trimorphic diaspores of annual desert halophyte A. centralasiatica exhibited diverse dormancy/germination behavior in respond to seasonal soil salinity fluctuation. Prolonging persistence of the seedbank and delaying depletion of diaspores under salt stress in situ primarily is due to inhibition of dormancy-break. The differences in dormancy/germination and seed persistence in the soil seedbank may be a bet-hadging strategy adapted to stressful temporal and spatial heterogeneity, and allows A. centralasiatica to persist in the unpredictable cold desert enevironment.

Aims Seeds are usually classified as short- or long-term persistent. It is still hardly understood how environmental conditions influence seed persistence. The study aimed to monitor the long-term effects of different moisture and substrate on seed persistence. Methods Seeds of three Rumex species buried in autumn 2009 in combinations of moisture and substrate were exhumed in spring 2015 and 2021 to test their persistence in the soil after 5.5 and 11.5 years, respectively. Long-term persistence data were compared with data from previous short-term experiment for the same species and environmental conditions reported in Abedi et al. (Plant Soil 374:485-495, 2014). Results No seeds of R.   acetosa were found viable after 1.5 years. Seeds of R.   acetosella retained viability after 11.5 years mostly in dry-loam (~ 60%) and moist-sand (~ 25%) test conditions and moisture levels were identified as the main driver. R.   maritimus retained ≥ 80% viability in moist and wet test conditions and > 40% in the dry test conditions. Conclusions For one ( R. acetosella ) of the three investigated species, the classification of soil seed bank type depended on environmental conditions, emphasizing the need to introduce a more detailed classification scheme for soil seed persistence and to include the information about extrinsic parameters in databases. However, in the other two species with transient ( R. acetosa ) and long-term persistent ( R. maritimus ) seed banks, there are rather intrinsic parameters that affect seed viability. Hence, both site-specific environmental factors as well as seed germination traits need full consideration in the classification of future soil seed bank studies.

Knotroot foxtail [Setaria parviflora (Poir.) Kerguélen], a perennial Setaria species, is becoming more problematic in forage and grazing systems across the southeastern United States. Setaria parviflora reproduces through the production of rhizomes and seeds, further complicating management strategies. Significant knowledge gaps exist regarding the biology and control of this species. This research aimed to understand the influence of burial depth on S. parviflora propagules and the physiological differences between it and other Setaria spp. Experiments were conducted between October 2019 and February 2021 in Clarke County, GA, to investigate the influence of burial depth (1, 2, 4, 8, and 16 cm) on the emergence and growth of S. parviflora rhizomes and seeds. Zero emergence was estimated at 8.7, 10.8, and 11.2 cm for small rhizomes, large rhizomes, and seeds, respectively. Therefore, producers could implement tillage events to a depth of 11.2 cm or greater to control S. parviflora. A separate study compared S. parviflora, yellow foxtail [Setaria pumila (Poir.) Roem. & Schult.], green foxtail [Setaria viridis (L.) P. Beauv.], and giant foxtail (Setaria faberi Herrm.) plant morphology. Despite similar aboveground appearances, S. pumila and S. parviflora had different total and belowground biomass 2 to 5 mo after emergence, which suggests differences in root formation and perennialization of S. parviflora. The present research determined that burying propagules using tillage could be included in management recommendations concerning S. parviflora; however, it should be complemented with herbicide applications during the growing season to assist in controlling S. parviflora plants produced by seeds.

One of the biggest issues in plant ecology is determining the interaction outcome between seeds and scatter-hoarding rodents because the latter has a dual role as dispersers and predators of seeds. Density-dependence contexts involving resource abundance largely influence the outcome of this interaction. Here, we investigated how the variation in the density of a large-seeded tropical tree (Joannesia princeps Vell) affects its probability of seed removal, consumption, dispersal, and burial by a neotropical rodent (Dasyprocta azarae Lichtenstein). We tested whether the elevated resource availability in high tree density areas would cause scatter hoarder’s satiation by decreasing seed removal and consumption (predator satiation hypothesis) or increasing seed dispersal and burial (predator dispersal hypothesis). We tracked the fate of 461 seeds in 14 plots with distinct J. princeps abundances inside a large Atlantic Forest fragment. We used spool-and-line tracking and camera trappings to determine seed fate and identify interacting animals. Agouti was the only species removing J. princeps seeds. Tree density benefitted J. princeps by increasing seed dispersal through buried seed but not affecting seed removal and consumption. This result shows how density-dependent contexts, such as tree density, may alter seed fate in seed–rodent interactions supporting future studies aiming to reestablishing seed dispersal functions in Atlantic Forest fragments.

Premise of the study: Seed longevity and persistence in soil seed banks may be especially important for population persistence in ecosystems where opportunities for seedling establishment and disturbance are unpredictable. The fire regime, an important driver of population dynamics in sagebrush steppe ecosystems, has been altered by exotic annual grass invasion. Soil seed banks may play an active role in postfire recovery of the foundation shrub Artemisia tridentata, yet conditions under which seeds persist are largely unknown. Methods: We investigated seed longevity of two Artemisia tridentata subspecies in situ by retrieving seed bags that were placed at varying depths over a 2 yr period. We also sampled naturally dispersed seeds in litter and soil immediately after seed dispersal and before flowering in subsequent seasons to estimate seed persistence. Key results: After 24 mo, seeds buried at least 3 cm below the soil surface retained 30-40% viability whereas viability of seeds on the surface and under litter declined to 0 and < 11%, respectively. The density of naturally dispersed seeds in the seed bank was highly heterogeneous both spatially and temporally, and attrition varied significantly by region. Conclusion: Our study suggests that Artemisia tridentata has the potential to form a short-term soil seed bank that persists longer than has been commonly assumed, and that burial is necessary for seed longevity. Use of seeding techniques that promote burial of some seeds to aid in formation of a soil seed bank may increase restoration potential.

is a dominant native perennial shrub on sand dunes in arid deserts of northwestern China, and is therefore widely used in sand dune stabilization in these regions. However, it remains largely unknown how seedling emergence of has adapted to unpredictable sand movement and extreme drought. Here we examined effects of seed burial depth, light intensity, and seed age on seedling emergence, and considered seed germination and seedling emergence strategies for the shrub's adaption to the desert environment. In our pot experiment, the optimum seeding depth for emergence of was 2 cm, indicating that for germination and seedling emergence only moderate sand burial is required. Light intensity at the surface soil (0 cm) was important for seedling emergence, while there was no significant difference between 50 and 20% light flux density, at burial depths of 1 and 2 cm, indicating that seeds had adapted to sand burial, while not exposure from sand erosion. We also found seedlings emerged in spring and in late summer to early autumn. Meanwhile, seedling emergence percentage for 3-year-old seeds was similar to that of 1-year-old seeds, which meant that seeds were well preserved under normal sand dune conditions, thus were capable of developing a persistent, but shallow soil seed-bank. These results indicated that germination and seedling emergence take a bet-hedging strategies to adapt to variable desert environments. Our study confirmed that desert shrubs combine strategies in its adaption to arid and variable sand environments.

Alpine cushion plants play keystone roles in regulating and sustaining various ecosystem functions, including enhancement and maintenance of community diversity and productivity. Therefore, their population dynamics may exert significant influences on alpine ecosystems. However, the mechanisms driving their population dynamics, particularly during critical early recruitment stages such as seedling emergence and subsequent growth, remain poorly understood. This study investigated how warming temperatures, intense UV‐B radiation, and increased seed burial depth affect the emergence, growth, and mortality of seedlings from 11 cushion plant species in the alpine subnival zones of the Himalaya‐Hengduan Mountains in southwestern China. Results revealed that deep seed burial (exceeding 1 cm) significantly suppressed seedling emergence in cushion species, with substantial loss of seed viability occurring within 3 months for seeds buried at greater depths. Warmed temperatures (> 20°C) accelerated emergence rates and enhanced seedling growth (increased height and leaf number), but also resulted in high seedling mortality rates (ranging from 60% to 100% in most species). In addition, intensified UV‐B radiation consistently impaired seedling recruitment across multiple stages, leading to reduced emergence percentages, stunted growth, and increased mortality rates. These findings suggest that the coarse, mobile substrates characteristic of subnival zones exacerbate natural constraints on seedling emergence in cushion plants. While increased temperatures may promote emergence and growth, they can also result in significant mortality, thereby hindering future population recruitment and expansion. Furthermore, enhanced UV‐B radiation due to ozone layer depletion poses additional threats to cushion populations. Nevertheless, the observed species‐specific responses to these factors indicate that cushion species may exhibit diverse population dynamics under future climate change scenarios. This study provides essential insights into the potential trajectories of alpine cushion populations under climate change, offering valuable implications for the conservation of ecosystems and biodiversity. This study investigated the effects of warming temperatures, intense UV‐B radiation, and seed burial depth on seedling emergence, growth, and survival of 11 cushion plant species in alpine subnival zones of the Himalaya‐Hengduan Mountains. Deep burial (> 1 cm) severely inhibited emergence in 10 species, with viability loss within 3 months. Warming accelerated emergence and growth but also increased mortality. Intense UV‐B radiation consistently impeded recruitment, reducing emergence, growth, and increasing mortality.

Dung beetles relocate vertebrate feces under the soil surface, and this behavior has many ecological consequences. In tropical forests, for example, seeds defecated by mammals that are subsequently buried by dung beetles are less likely to suffer predation. While the effects of dung beetles on the fate of defecated seeds have been relatively well studied, their effect on seeds already buried in the soil has not. To contribute to fill this gap, we designed a study with three objectives: (a) Describe the vertical re-distribution of soil seeds that occurs due to dung beetle activity; (b) Determine if beetle activity favors establishment of seedlings from the soil seed bank; and (c) Determine if the effect of dung beetles is stronger in sites of recurrent mammal defecation. We carried out three complementary field experiments, one with artificial seeds (plastic beads) of three sizes buried at known depths, one with two species of seeds buried at those same depths, and one with the natural soil seed bank in sites of single vs. recurrent defecation. Buried beads were moved by dung beetles along the vertical axis, both upwards (9.5%) and downwards (11.5%); smaller beads were more frequently moved downwards while the contrary occurred for larger beads. Dung beetle activity caused an increase in seedling establishment, both from experimentally buried seeds and from the natural seed bank. Defecation recurrence had no effect on seedling establishment. We conclude that dung beetle activity affects seed bank dynamics with important consequences for seedling establishment in tropical forests.

The independent domestication of crop plants in several regions of the world formed the basis of human civilizations, and attracts considerable interest from archaeologists and biologists. Selection under cultivation led to a suite of domestication traits which distinguish crops from their wild progenitors, including larger seeds in most seed crops. This selection may be classified as ‘conscious’ or ‘unconscious’ selection according to whether humans were aware of the changes that they were driving. The hypothesis that human cultivation buried seeds deeper than natural dispersal, exerting unconscious selection favouring larger seeds with greater reserves, was tested. Using a comparative approach, accessions of eight grain legumes, originating from independent domestication centres across several continents, were sampled. Seeds were planted at different depths in a controlled environment, and seedling emergence scored for 5 weeks after sowing. Domestication in all species was associated with increased seed mass. In three species, greater mass was not correlated with increased ability to emerge from depth. In five species, emergence depth did correlate with mass, suggesting that selection during domestication may have acted on emergence depth. However, domestication only had a significant effect in two of these species (lentil and mung bean), and the increase in depth was no more than predicted by a cube-root allometric relationship with seed mass. The results do not support the hypothesis that burial under cultivation was a general selection mechanism for increased seed mass during the domestication of grain legumes, but it may have acted in particular species or regions.

Seed dispersal and burial are important processes in the expansion and restoration of Zostera marina (eelgrass) meadows. The depth at which seeds are buried is a significant factor contributing to the success of seedling survival. If seeds are buried below 6 cm, it is unlikely that viable seedlings will develop, while shallow burials protect seeds from predation on the sediment surface. Burrowing behavior of infaunal organisms is one factor that contributes to seed burial with a potentially positive or negative influence on seedling survival. In this study, we designed a laboratory experiment to determine the relationship between lugworm (Abarenicola pacifica) density and eelgrass seed burial. Three treatments (no worms, low-density, and high-density of worms) with three replicates each were used to quantify seed burial. Each replicate was seeded with a blend of seed mimics and real seeds. After 25 days, three cores were extracted from each replicate and the depths of the seeds recorded. In the high-density worm treatments, most of the seeds and mimics were buried below the 6 cm critical depth, while in the low-density treatments most seeds were found shallower than 3 cm. These results agree with previous work on the burying capacity of infaunal organisms, and strongly suggest that the presence and activity of infauna can determine the success of Z. marina meadow expansion and restoration.