Dispersal syndrome influences the match between seed rain and soil seed bank of woody species in a Neotropical dry forest

Objective: To investigate the impact of different slope directions on the quantity and quality of the soil seed bank and seedling germination process of Castanopsis hystrix plantations. Method: Fixed sample plots in forest stands of Castanopsis hystrix were established on different slope directions (sunny slope, semi-sunny slope, semi-shady slope, and shady slope). The characteristics of the forest stand were investigated, and per-wood scaling was carried out. The temporal dynamics of the seed rain and seed bank were quantified using seed rain collectors and by collecting soil samples from different depths. The quantity and quality of the seeds were determined, and the vigor of mature seeds was measured throughout the study. Results: (1) The diffusion of Castanopsis hystrix seed rain started in mid-September, reached its peak from late October to early November, and ended in mid-December. (2) The dissemination process, occurrence time, and composition of the seed rain varied between the different slope directions. The seed rain intensity on the semi-sunny slope was the highest (572.75 ± 9.50 grains∙m−2), followed by the sunny slope (515.60 ± 10.28 grains∙m−2), the semi-shady slope (382.13 ± 12.11 grains∙m−2), and finally the shady slope (208.00 ± 11.35 grains∙m−2). The seed rain on the sunny slope diffused earliest and lasted the longest, while the seed rain on the shady slope diffused latest and lasted the shortest time. Seed vigor and the proportion of mature seeds within the seed rain were greatest on the semi-sunny slope, followed by the sunny slope, semi-shady slope, and the shady slope. (3) From the end of the seed rain to August of the following year, the amount of total reserves of the soil seed banks was highest on the semi-sunny slope, followed by the sunny slope then the semi-shady slope, and it was the lowest on the shady slope. The amount of mature, immature, gnawed seeds and seed vigor of the soil seed bank in various slope directions showed a decreasing trend with time. The seeds of the seed bank in all slope directions were mainly distributed in the litter layer, followed by the 0–2 cm humus layer, and only a few seeds were present in the 2–5 cm soil layer. (4) The seedling density of Castanopsis hystrix differed significantly on the different slope directions. The semi-sunny slope had the most seedlings, followed by the sunny slope, semi-shady slope, and the shady slope. Conclusions: The environmental conditions of the semi-sunny slope were found to be most suitable for the seed germination and seedling growth of Castanopsis hystrix, and more conducive to the regeneration and restoration of its population.

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Seasonal variation in soil seed bank size and species composition of selected habitat types in Maputaland, South Africa

Bothalia ◽

10.4102/abc.v37i2.323 ◽

2007 ◽

Vol 37 (2) ◽

pp. 249-258 ◽

Cited By ~ 7

Author(s):

M. J. S. Kellerman ◽

M. W. Van Rooyen

Keyword(s):

South Africa ◽

Seasonal Variation ◽

Species Composition ◽

Seed Bank ◽

Soil Seed Bank ◽

Woody Species ◽

Forest Edge ◽

Seed Banks ◽

Habitat Types ◽

Open Woodland

Seasonal variation in seed bank size and species composition of five selected habitat types within the Tembe Elephant Park. South Africa, was investigated. At three-month intervals, soil samples were randomly collected from five different habitat types: a, Licuati forest; b, Licuati thicket; c, a bare or sparsely vegetated zone surrounding the forest edge, referred to as the forest/grassland ecotone; d, grassland; and e, open woodland. Most species in the seed bank flora were either grasses, sedges, or forbs, with hardly any evidence of woody species. The Licuati forest and thicket soils produced the lowest seed densities in all seasons. Licuati forest and grassland seed banks showed a two-fold seasonal variation in size, those of the Licuati thicket and woodland a three-fold variation in size, whereas the forest/grassland ecotone maintained a relatively large seed bank all year round. The woodland seed bank had the highest species richness, whereas the Licuati forest and thicket soils were poor in species. Generally, it was found that the greatest correspondence in species composition was between the Licuati forest and thicket, as well as the forest/grassland ecotone and grassland seed bank floras.

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Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

Journal of Plant Ecology ◽

10.1093/jpe/rtaa008 ◽

2020 ◽

Vol 13 (3) ◽

pp. 256-265 ◽

Cited By ~ 1

Author(s):

José Djalma de Souza ◽

Bruno Ayron de Souza Aguiar ◽

Danielle Melo dos Santos ◽

Vanessa Kelly Rodrigues de Araujo ◽

Júlia Arruda Simões ◽

...

Keyword(s):

Seed Bank ◽

Linear Models ◽

Temporal Dynamics ◽

Soil Seed Bank ◽

Seed Banks ◽

Dry Forest ◽

Herbaceous Species ◽

Physical Dormancy ◽

Soil Seed Banks ◽

Interspecific Differences

Abstract Aims In dry tropical forests, herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the soil. Evolutionarily acquired, these mechanisms are efficient for the establishment and survival of these herbs, especially in forests with unpredictable climates, such as the Caatinga. Thus, our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome, to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical forest. Methods Seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical dormancy. We collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the greenhouse. We verified the differences in germination and seed bank emergence in the soil by generalized linear models. Important Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous species. We found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic seasons. In perennial herbs, consecutive lack of emergence between seasons and years was frequent, which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument barriers. In these species, seed dimorphism and dormancy may confer additional advantages to their survival. Moreover, presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall unpredictability. In contrast, we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes, as evidenced by the increase and significant reduction of its emergence in the soil seed bank. These differences acquired evolutionarily are advantageous for the establishment of herbaceous populations, mainly in semiarid regions with an unpredictable climate.

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Seed Rain, Soil Seed Bank, and Seedling Emergence Indicate Limited Potential for Self-Recovery in a Highly Disturbed, Tropical, Mixed Deciduous Forest

Plants ◽

10.3390/plants9101391 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1391

Author(s):

Anussara Chalermsri ◽

La-aw Ampornpan ◽

Witoon Purahong

Keyword(s):

Mortality Rate ◽

Seed Bank ◽

Tree Species ◽

Deciduous Forest ◽

Soil Seed Bank ◽

Seedling Emergence ◽

Seed Rain ◽

Reproductive Phenology ◽

Mixed Deciduous Forest ◽

Standing Vegetation

Human activity negatively affects the sustainability of forest ecosystems globally. Disturbed forests may or may not recover by themselves in a certain period of time. However, it is still unclear as to what parameters can be used to reasonably predict the potential for self-recovery of human-disturbed forests. Here, we combined seed rain, soil seed bank, and seed emergence experiments to evaluate the potential for self-recovery of a highly disturbed, tropical, mixed deciduous forest in northeastern Thailand. Our results show a limited potential for self-recovery of this forest due to low seedling input and storage and an extremely high mortality rate during the drought period. There were 15 tree species of seedlings present during the regeneration period in comparison with a total number of 56 tree species in current standing vegetation. During the dry season, only four tree seedling species survived, and the highest mortality rate reached 83.87%. We also found that the correspondence between the combined number of species and composition of plant communities obtained from seed rain, soil seed bank, and seedling emergence experiments and the standing vegetation was poor. We clearly show the temporal dynamics of the seed rain and seedling communities, which are driven by different plant reproductive phenology and dispersal mechanisms, and drought coupled with mortality. We conclude that this highly disturbed forest needs a management plan and could not recover by itself in a short period of time. We recommend the use of external seed and seedling supplies and the maintenance of soil water content (i.e., shading) during periods of drought in order to help increase seedling abundances and species richness, and to reduce the mortality rate.

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Seed rain, soil seed bank and regeneration ofLarix principis-rupprechtiistands in the Upper Reaches of Wenyuhe

Acta Ecologica Sinica ◽

10.5846/stxb201406181268 ◽

2015 ◽

Vol 35 (11) ◽

Author(s):

高润梅 GAO Runmei ◽

石晓东 SHI Xiaodong ◽

郭跃东 GUO Yuedong ◽

樊兰英 FAN Lanying

Keyword(s):

Seed Bank ◽

Soil Seed Bank ◽

Seed Rain

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Restoration of high species density in calcareous grassland: the role of seed rain and soil seed bank

Applied Vegetation Science ◽

10.2307/1479088 ◽

1998 ◽

Vol 1 (1) ◽

pp. 91-100 ◽

Cited By ~ 71

Author(s):

J.H. Willems ◽

L.P.M. Bik

Keyword(s):

Seed Bank ◽

Soil Seed Bank ◽

Seed Rain ◽

Species Density ◽

Calcareous Grassland

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Seed and vegetation dynamics in an alpine herb field: effects of disturbance type

Canadian Journal of Botany ◽

10.1139/b93-052 ◽

1993 ◽

Vol 71 (3) ◽

pp. 471-485 ◽

Cited By ~ 68

Author(s):

Jeanne C. Chambers

Keyword(s):

Seed Bank ◽

Vegetation Cover ◽

Soil Seed Bank ◽

Vegetative State ◽

Seed Rain ◽

Life History Strategies ◽

Small Scale ◽

Pocket Gopher ◽

Growing Seasons ◽

Highly Correlated

Relationships among the aboveground vegetation, seed rain, and seed bank were examined on a late seral herb field characterized by pocket gopher disturbance and on an early seral gravel borrow that had been severely disturbed 35 years ago on the Beartooth Plateau, Montana. Aboveground vegetation cover was assessed by species in twelve 5-m2 plots. Seed rain was sampled during the 1988, 1989, and 1990 growing seasons with pitfall traps, and the soil seed bank was sampled in fall 1989, spring 1990, and fall 1990. The seed rain (filled seeds) on the borrow area ranged from 7730 to 14 009 seeds/m2 and was higher than that found on other alpine sites; that on the Geum turf ranged from 3375 to 6179 seeds/m2 and was similar to that for other alpine sites. Although highly variable among dates on the borrow area, the seed banks were similar to those of comparable alpine sites. Seed bank density ranged from 1980 to 6003 seeds/m2 on the borrow area and from 3202 to 4647 seeds/m2 on the Geum turf area. The Geum turf area had higher vegetation cover than the borrow area (87 vs. 25%) and higher numbers of species in the aboveground vegetation, seed rain, and seed bank. Relationships among the aboveground vegetation, seed rain, and seed bank were largely determined by the disturbance characteristics of the different sites and the life-history strategies of the dominant species. Medium-lived species, primarily grasses, with high production of small and compact seeds had colonized the borrow area. Despite establishment of other species, 35 years after disturbance the medium-lived species still dominated the aboveground vegetation, seed rain, and seed bank. Species abundances in the three different components were all highly correlated. In contrast, on the Geum turf area there were no correlations among the aboveground vegetation, seed rain, or seed bank. Long-lived forbs that produced low numbers of relatively large seeds dominated the aboveground vegetation and persisted on the area primarily in the vegetative state. The same medium-lived species that dominated the borrow area had the highest abundance in the seed rain on the Geum turf area and appeared to persist by colonizing small-scale disturbances caused by gopher burrowing. Short-lived species with small, long-lived seeds existed on the site primarily through a highly persistent seed bank. The relationships among the aboveground vegetation, seed rain, and seed bank on the Geum turf and borrow areas are compared with those observed for more temperate systems following disturbance. Key words: alpine, herb field, Geum turf, disturbance, vegetation cover, seed rain, seed bank, colonization, establishment, succession.

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