Tree species determine soil seed bank composition and its similarity with understory vegetation in a semi-arid African savanna

O objetivo do presente trabalho foi estudar o banco de sementes no solo de um fragmento florestal com Araucaria angustifolia (Bert.) O. Ktze. no estado do Paraná. Para isso, investigou-se a distribuição vertical das sementes, a influência do sombreamento sobre a emergência das plântulas, sua identificação e quantificação. A distribuição vertical de sementes em quatro camadas foi analisada através da identificação e quantificação das plântulas emergentes em casa de vegetação, levando em consideração o nível de sombreamento. Os dados referentes ao banco de sementes foram obtidos no período de 210 dias, por meio de identificação botânica e contagens semanais das plântulas germinadas das quatro profundidades de solo em quatro parcelas experimentais. As amostras foram colocadas para germinar sob 0 e 50% de sombreamento em casa de vegetação. Os resultados obtidos no estudo de banco de sementes permitiram as seguintes conclusões: o banco de sementes parece ser pobre em espécies arbóreas e abundante em espécies herbáceas; o banco de sementes das espécies arbóreas foi maior na segunda camada; ocorreu maior germinação sob 0% de sombreamento. Provavelmente, a estratégia de regeneração da maioria das espécies presentes nessa área de estudo parece não ser pelo banco de sementes no solo.Palavras-chave: Banco de sementes no solo; Araucaria angustifolia; fragmento florestal. AbstractSoil seed bank analysis in a forest fragment with Araucaria angustifolia, State of Parana. A research on soil seed bank had been developed in an Araucaria angustifolia (Bert.) O. Ktze. forest fragment in the State of Paraná. It had surveyed vertical distribution of seeds within the soil and shadow influence on seedling emergence, besides the improvement of their identification and quantity measuring. Vertical distribution of seeds in four soil layers had been analyzed by identification and quantification of germinated seedlings in greenhouse, with full light or 50% shaded conditions. Data related to seedlings of trees, weeds, grasses and lianas were calculated separately in weekly intervals during a 210-day period. Results suggested that the soil seed bank in this forest was poor in relation to tree species, in diversity as far as density. On the other hand, seeds of grasses and weeds decreased along vertical soil profile, and forest tree species tended to abundance in the 5-10 cm layer. Germination was higher with full light than in 50% shaded conditions. Probably, regeneration strategy for most species in this focused area doesn’t seem to be soil seed bank.Keywords: Soil seed bank; Araucaria angustifolia; forest fragment.

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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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The Relationship Between Distance From Water and the Soil Seed Bank in a Grazed Semi-Arid Subtropical Rangeland

Australian Journal of Botany ◽

10.1071/bt9960421 ◽

1996 ◽

Vol 44 (4) ◽

pp. 421 ◽

Cited By ~ 33

Author(s):

SC Navie ◽

RA Cowley ◽

RW Rogers

Keyword(s):

Seed Bank ◽

Soil Seed Bank ◽

Common Species ◽

Pressure Gradients ◽

Standing Vegetation ◽

Open Woodland ◽

The Relationship ◽

Germinable Seed ◽

Eucalyptus Populnea ◽

Semi Arid

The germinable soil seed bank of a grassy Eucalyptus populnea F.Muell, open woodland was investigated in relationship to distance from water (away from a bore-drain) on North Yancho Station, near Bollon in southern semi-arid Queensland. The germinable soil seed bank was both diverse and abundant, 69 taxa of seedlings being identified to species and 2 more to genus. A mean density of 13 207 ± 4160 seeds m-2 was recorded, with over 80% of the seed being from the annual forbs Crassula sieberana (Schultes & J.H.Shultes) Druce, Wahlenbergia tumidifructa P.J.Smith and Dysphania gomulifera (Nees) Paul G.Wilson. Most common species showed spatial variation in their germinable seed density with relation to distance from water, resembling the patterns previously reported by other authors for standing vegetation under stocking pressure gradients.

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Regeneration Potential of Floodplain Forests Under the Influence of Nonnative Tree Species: Soil Seed Bank Analysis in Northern Italy

Restoration Ecology ◽

10.1111/rec.12027 ◽

2013 ◽

Vol 22 (1) ◽

pp. 22-30 ◽

Cited By ~ 11

Author(s):

Sandra Skowronek ◽

André Terwei ◽

Stefan Zerbe ◽

Inga Mölder ◽

Peter Annighöfer ◽

...

Keyword(s):

Seed Bank ◽

Tree Species ◽

Soil Seed Bank ◽

Northern Italy ◽

Floodplain Forests ◽

Regeneration Potential

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Soil seed bank recovery occurs more rapidly than expected in semi-arid Mediterranean gypsum vegetation

Annals of Botany ◽

10.1093/aob/mcr260 ◽

2011 ◽

Vol 109 (1) ◽

pp. 299-307 ◽

Cited By ~ 19

Author(s):

J. M. Olano ◽

I. Caballero ◽

A. Escudero

Keyword(s):

Seed Bank ◽

Soil Seed Bank ◽

Semi Arid

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Soil seed bank dynamics under the influence of grazing as alternative explanation for herbaceous vegetation transitions in semi-arid rangelands

Ecological Modelling ◽

10.1016/j.ecolmodel.2016.07.013 ◽

2016 ◽

Vol 337 ◽

pp. 253-261 ◽

Cited By ~ 9

Author(s):

Frank van Langevelde ◽

Zewdu K. Tessema ◽

Willem F. de Boer ◽

Herbert H.T. Prins

Keyword(s):

Seed Bank ◽

Alternative Explanation ◽

Soil Seed Bank ◽

Herbaceous Vegetation ◽

Seed Bank Dynamics ◽

Arid Rangelands ◽

Semi Arid

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Soil seed bank characteristics in relation to land use systems and distance from water in a semi-arid rangeland of southern Ethiopia

South African Journal of Botany ◽

10.1016/j.sajb.2005.09.003 ◽

2006 ◽

Vol 72 (2) ◽

pp. 263-271 ◽

Cited By ~ 28

Author(s):

T.B. Solomon ◽

H.A. Snyman ◽

G.N. Smit

Keyword(s):

Land Use ◽

Seed Bank ◽

Soil Seed Bank ◽

Southern Ethiopia ◽

Land Use Systems ◽

Semi Arid ◽

Arid Rangeland

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Abandoned corrals: colonization and vegetation recovery of ephemeral habitats in silvo-pastoral systems

Journal of Plant Ecology ◽

10.1093/jpe/rtaa062 ◽

2020 ◽

Vol 13 (6) ◽

pp. 722-731

Author(s):

Arie Vinograd ◽

Eli Zaady ◽

Jaime Kigel

Keyword(s):

Seed Bank ◽

Negative Impact ◽

Soil Seed Bank ◽

Mineral Resources ◽

Natural Forests ◽

Planted Forests ◽

Pastoral Systems ◽

Animal Protection ◽

Dispersal Vectors ◽

Semi Arid

Abstract Aims Management of silvo-pastoral systems in planted and natural forests in semi-arid Mediterranean regions often employs seasonal night corrals for animal protection. This management system changes the spatial distribution of animal excreta, resulting in a net transfer of soil mineral resources and their accumulation in the corrals. After abandonment, corrals are colonized by ruderal species, becoming focal sources for their spread in the forest. We aimed to implement a rational management of seasonal sheep corrals based on a better understanding of the vegetation processes occurring in abandoned corrals, in order to alleviate their negative impact in the forest. Methods Relationships between temporal changes in the vegetation, the soil seed-bank and levels of soil nutrients were studied in a chronosequence of abandoned sheep corrals and compared with nearby reference plots in planted Eucalyptus forests grazed by sheep in the semi-arid North-Western Negev, Israel. The region has a bi-seasonal Mediterranean climate, with high dominance of annual species in the grazing range. Important Findings Abandoned sheep corrals were colonized by seeds of ruderals originating in older abandoned corrals. Subsequent successional changes occur at a slow rate, driven by the depletion of soil resources in the abandoned corrals, and were still in progress 20 years after abandonment. Ruderals were gradually replaced, first by taller grasses and followed by short grasses, but most forbs and particularly geophytes did not recover during this period. Recovery of the original herbaceous vegetation in the corrals was through seed dispersal from the surrounding vegetation, not from the original soil seed-bank remaining in the corrals after abandonment. Ruderal species in the grazed, planted forests behave as patch-tracking metapopulations. Their persistency depends on constant creation of new corrals compensating for the gradually dwindling populations in older abandoned corrals, and on the availability of dispersal vectors.

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