Natural regeneration triggers compositional and functional shifts in soil seed banks

Soil seed banks have been used for investigation of natural regeneration of forests. In this study, we compared seed density and species composition of soil seed banks of trees among natural forests, restored forests of different ages, and abandoned agricultural land. The soil seed banks were collected from a natural forest (NF), 12-year-old and 17-year-old restoration sites (RF12y and RF17y), and 17-year-old abandoned site (AA) at Ban Mae Sa Mai, Chiang Mai, Thailand. A seedling emergence technique was used to assess seed density and species of emerged seedlings was identified. We found 5-8 tree species at each site. Seed densities in the study areas ranged from 43 to 298 seeds/m2. The seed density of RF12y was significantly higher than that of both NF and AA but not significantly different than RF17y (p < 0.01). Although there was no significant relationship between the restoration ages and the seed densities of the soil seed banks, the species composition of standing vegetation was related to the seed bank species. Sorensen’s similarities between the species composition of the soil seed banks and the existing trees in each area were between 0 and 13.79%, suggesting seed dispersal of both within and across study sites. Eight out of fourteen species in the soil seed banks were dispersed into restoration sites without standing vegetation of those species. Seven of those were animal-dispersed species. The selected native trees, framework species, attracted small seed dispersers into the study areas, especially at the restoration sites. This finding suggests that active forest restoration improved natural regeneration in restoration sites as well as neighboring areas via seed dispersal.

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Natural vegetation regeneration from soil seed banks in the cultivated edges of Sudd wetlands in Juba, Southern Sudan

East African Journal of Science, Technology and Innovation ◽

10.37425/eajsti.v2i2.214 ◽

2021 ◽

Vol 2 (2) ◽

Author(s):

Josephine Esaete ◽

Augustine Bongo ◽

Thomas Lado ◽

Tomor Bojoi ◽

Henry Busulwa

Keyword(s):

Species Richness ◽

Species Composition ◽

Seed Bank ◽

Natural Regeneration ◽

Soil Seed Bank ◽

Seed Banks ◽

Interquartile Range ◽

Seed Density ◽

Soil Seed Banks ◽

Species Richness And Diversity

Soil seed banks are important for regeneration of degraded wetlands ecosystems. The Sudd wetlands of Juba city have long been encroached for crop cultivation. Seedling germination was monitored in a greenhouse to establish possible natural regeneration in Mindiari, Rejaf and Roton wetlands in the Sudd. Sixty-four species germinated from the soil seed bank of which 12.5% were dominated by Cyperus difformis and Typha capensis. The findings showed that median wetland species richness in Mindiari was 1.5 (interquartile range = 0.75?3.5), Rejaf 2.5 (interquartile range = 1.0 ? 4.0), Roton 3 (interquartile range = 1.0 ? 5.0) while median Shannon-Wiener diversity was 1.5 (1.14 ?1.73), 1.43 (1.01?1.66), 1.15 (0.98?1.67) for Mindiari, Rejaf and Roton respectively. Both the median seed species richness and diversity were not significantly different among the study wetlands. The median of seed density (56.1) was significantly higher in Roton than in Mindiari (36.7) and Rejaf (29.4) wetlands. The NMDS results showed that species composition of Mindiari and Rejaf was different from Roton. It is concluded that growing crops in wetlands did not influence species richness and diversity but it reduced seed density and altered species composition. Although wetland species were not significantly different in the three-wetland categories, dominance of canopy species belonging to Typhaceae and Cyperaceae indicates that these species are resilient to cultivation and could facilitate natural regeneration of cultivated wetlands edges of the Sudd region in Juba. Further research should examine effect of cultivation duration and flooding regimes on soil seed bank species richness, diversity, and density and composition.

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Seed rain and soil seed banks in Chinese fir plantations and an adjacent natural forest in southern China: implications for the regeneration of native species

10.22541/au.163310017.70875649/v1 ◽

2021 ◽

Author(s):

Bo Liu ◽

Qingqing Liu ◽

Chenxi Zhu ◽

Zhigang Liu ◽

Zhijun Huang ◽

...

Keyword(s):

Natural Regeneration ◽

Native Species ◽

Southern China ◽

Seed Banks ◽

Seed Rain ◽

Chinese Fir ◽

Natural Forest ◽

Ecosystem Functions ◽

Soil Seed Banks ◽

Mixed Plantation

The natural regeneration of native broadleaved species underneath forest monoculture plantations is important to recover ecosystem functions and to mitigate adverse environmental effects. To understand how seed rain and soil seed banks facilitate natural regeneration, we surveyed their density and composition in a monoculture Chinese fir plantation, a mixed Chinese fir–broadleaf plantation, and an adjacent natural broadleaved forest for two years in southern China. Twenty-eight species (16 families) were in seed rain, and 45 species (27 families) were in soil seed banks. Seed rain density did not differ significantly across stands; however, the number of taxa in seed rain was highest in the mixed plantation and lowest in the natural forest. Seed bank density was significantly higher in the mixed plantation than in the other stands. The Sørensen similarity indices of species composition between seed sources and aboveground vegetation were relatively low (<0.50). In addition, the seeds of native tree species common to the seed banks of the three forests indicated the adjacent natural forest was a seed source for the natural regeneration of native species in forest plantations. To augment regeneration and accelerate the rate of conversion, we recommend direct seeding or planting of desired species.

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Effects of Different Dune Positions and Microbiotic Crusts on Soil Seed Banks in the Gurbantonggut Desert

Arid Zone Research ◽

10.3724/sp.j.1148.2008.00107 ◽

2008 ◽

Vol 25 (1) ◽

pp. 107-113

Author(s):

Rong-yi CHEN

Keyword(s):

Seed Banks ◽

Soil Seed Banks ◽

Microbiotic Crusts

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Classification of Post-Fire Responses of Woody Plants to include Pyrophobic Communities

Fire ◽

10.3390/fire3020015 ◽

2020 ◽

Vol 3 (2) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

Lynda D. Prior ◽

David M. J. S. Bowman

Keyword(s):

Woody Plants ◽

Seed Banks ◽

Classification Systems ◽

Woody Vegetation ◽

General Category ◽

Conifer Species ◽

Soil Seed Banks ◽

Obligate Seeder ◽

In Fire

Developing standardised classification of post-fire responses is essential for globally consistent comparisons of woody vegetation communities. Existing classification systems are based on responses of species growing in fire-prone environments. To accommodate species that occur in rarely burnt environments, we have suggested some important points of clarification to earlier schemes categorizing post-fire responses. We have illustrated this approach using several Australasian conifer species as examples of pyrophobic species. In particular, we suggest using the term “obligate seeder” for the general category of plants that rely on seed to reproduce, and qualifying this to “post-fire obligate seeder” for the narrower category of species with populations that recover from canopy fire only by seeding; the species are typically fire-cued, with large aerial or soil seed banks that germinate profusely following a fire, and grow and reproduce rapidly in order to renew the seed bank before the next fire.

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