Seedling Recruitment in Forests: Calibrating Models to Predict Patterns of Tree Seedling Dispersion

Ecology ◽  
1994 ◽  
Vol 75 (6) ◽  
pp. 1794-1806 ◽  
Author(s):  
Eric Ribbens ◽  
John A. Silander ◽  
Stephen W. Pacala
2019 ◽  
Vol 35 (2) ◽  
pp. 74-82 ◽  
Author(s):  
Hamza Issifu ◽  
George K. D. Ametsitsi ◽  
Lana J. de Vries ◽  
Gloria Djaney Djagbletey ◽  
Stephen Adu-Bredu ◽  
...  

AbstractDifferential tree seedling recruitment across forest-savanna ecotones is poorly understood, but hypothesized to be influenced by vegetation cover and associated factors. In a 3-y-long field transplant experiment in the forest-savanna ecotone of Ghana, we assessed performance and root allocation of 864 seedlings for two forest (Khaya ivorensis and Terminalia superba) and two savanna (Khaya senegalensis and Terminalia macroptera) species in savanna woodland, closed-woodland and forest. Herbaceous vegetation biomass was significantly higher in savanna woodland (1.0 ± 0.4 kg m−2 vs 0.2 ± 0.1 kg m−2 in forest) and hence expected fire intensities, while some soil properties were improved in forest. Regardless, seedling survival declined significantly in the first-year dry-season for all species with huge declines for the forest species (50% vs 6% for Khaya and 16% vs 2% for Terminalia) by year 2. After 3 y, only savanna species survived in savanna woodland. However, best performance for savanna Khaya was in forest, but in savanna woodland for savanna Terminalia which also had the highest biomass fraction (0.8 ± 0.1 g g−1 vs 0.6 ± 0.1 g g−1 and 0.4 ± 0.1 g g−1) and starch concentration (27% ± 10% vs 15% ± 7% and 10% ± 4%) in roots relative to savanna and forest Khaya respectively. Our results demonstrate that tree cover variation has species-specific effects on tree seedling recruitment which is related to root storage functions.


1996 ◽  
Vol 26 (4) ◽  
pp. 584-589 ◽  
Author(s):  
S.K. Bank ◽  
P. Rao ◽  
R.S. Tripathi ◽  
H.N. Pandey

Recruitment and survival of four important broad-leaved tree species, viz Quercusdealbata L., Quercusgriffithii Hk., Rhododendronarboreum Sm., and Schimakhasiana Dyer., were studied over 2 years in the undisturbed, mildly disturbed and highly disturbed forest stands of a subtropical humid forest of Meghalaya, northeast India. Recruitment of S. khasiana seedlings was maximum in the highly disturbed stand, while Q. dealbata seedlings were abundant in the undisturbed and mildly disturbed stands. Seedlings of Q. dealbata, Q. griffithii, and R. arboreum were equally successful in all the stands, while S. khasiana seedlings showed better survival in the highly disturbed stand than in the mildly disturbed and undisturbed stands. Six microenvironmental factors, viz photosynthetically active radiation, relative humidity, air temperature, soil temperature, soil moisture, and thickness of litter on the forest floor, were correlated with the age-specific mortality rate of seedlings. In Q. dealbata, Q. griffithii, and S. khasiana, mortality rate was significantly affected by microenvironmental factors, while in R. arboreum mortality was not correlated with any of the microenvironmental factors. On the basis of seedling recruitment and survival pattern, it was concluded that Q. dealbata, Q. griffithii, and R. arboreum were successful in both disturbed and undisturbed forest stands, while S. khasiana seedlings showed better survival and establishment in the disturbed stands.


Plant Disease ◽  
2018 ◽  
Vol 102 (3) ◽  
pp. 640-644 ◽  
Author(s):  
Mary Ridout ◽  
George Newcombe

Poor seedling performance and reduced seed emergence are often ascribed to known pathogens that cause low seedling recruitment and poor seed emergence in forest nurseries and regeneration plantings. On the other hand, foliar endophytes are often overlooked as a source of poor emergence or tree seedling disease. Here, we show that an endophytic fungus common to the foliar microbiome of Pinus ponderosa acts as a cryptic pathogen in delaying emergence. In a series of experiments, we inoculated seed of P. ponderosa with a suspension of Sydowia polyspora 12 h prior to sowing. S. polyspora reduced seed emergence of its host, P. ponderosa, by as much as 30%. A tetrazolium chloride viability assay showed that S. polyspora reduces emergence by preventing germination; seed remained viable. In sum, pathogens affecting tree seed emergence and seedling recruitment may be endophytic as well as in seed and soil and deserve greater attention in studies of natural regeneration.


2013 ◽  
Vol 287 ◽  
pp. 140-146 ◽  
Author(s):  
Tony Vizcarra Bentos ◽  
Henrique E.M. Nascimento ◽  
G. Bruce Williamson

Oecologia ◽  
2015 ◽  
Vol 179 (2) ◽  
pp. 599-608 ◽  
Author(s):  
Lise Tingstad ◽  
Siri Lie Olsen ◽  
Kari Klanderud ◽  
Vigdis Vandvik ◽  
Mikael Ohlson

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Esther R. Frei ◽  
Eva Bianchi ◽  
Giulietta Bernareggi ◽  
Peter Bebi ◽  
Melissa A. Dawes ◽  
...  

2007 ◽  
Vol 37 (1) ◽  
pp. 103-115 ◽  
Author(s):  
Georges Kunstler ◽  
Joël Chadœuf ◽  
Etienne K Klein ◽  
Thomas Curt ◽  
Monique Bouchaud ◽  
...  

Encroachment of trees into low-productivity grasslands is a serious threat to grassland biodiversity throughout Europe. Although the rate of encroachment of trees into grassland is variable and poorly understood, it is thought to result from variation in tree seedling recruitment, which is limited mainly by the availability of safe sites and the dispersal distances of propagules. In this study, we established spatially explicit models of seedling recruitment for two major sub-Mediterranean trees: Quercus pubescens Willd. and Fagus sylvatica L. We quantified the spatial distribution of Q. pubescens and F. sylvatica seedlings up to 20 years old at three grassland sites. We also quantified the spatial distribution and size of mature trees and of the two dominant species of shrubs, Buxus sempervirens L. and Juniperus communis L., at each of the three sites. Ninety-eight percent of the regeneration took place under shrub canopy. Quercus pubescens seedlings showed higher seedling production per unit of canopy area and longer mean effective dispersal distances than did F. sylvatica seedlings. Quercus pubescens seedlings also had a large advantage over F. sylvatica seedlings for establishment in open areas. Juniperus shrubs were better safe sites for the establishment of Q. pubescens and F. sylvatica seedlings than were Buxus shrubs. We calculated indices of seedling dispersal limitation and safe site availability for recruitment for four dates. In the dolomitic Causse grasslands examined in this study, the availability of safe sites for germination and survival was far more important than seedling dispersal limitation for recruitment of both tree species.


2014 ◽  
Vol 68 (1) ◽  
pp. 33-45 ◽  
Author(s):  
A. C. Medeiros ◽  
E. I. von Allmen ◽  
C. G. Chimera

2019 ◽  
Vol 35 (5) ◽  
pp. 223-236 ◽  
Author(s):  
Franck Trolliet ◽  
David Bauman ◽  
Pierre-Michel Forget ◽  
Jean-Louis Doucet ◽  
Jean-François Gillet ◽  
...  

AbstractLarge frugivores provide critical seed dispersal services for many plant species and their extirpation from forested ecosystems can cause compositional shifts in regenerating plant cohorts. Yet, we still poorly understand whether large seed-dispersers have complementary or redundant roles for forest regeneration. Here, to assess the functional complementarity of large-bodied frugivores in forest regeneration, we quantified the effects of varying abundance of hornbills, primates and the forest elephant on the density, species richness and the mean weighted seed length of animal-dispersed tree species among seedlings in five sites in a forest–savanna mosaic in D. R. Congo, while accounting for percentage forest cover and the local presence of fruiting trees. We found that the abundance of primates was positively associated with species richness of seedlings, while percentage forest cover was negatively associated (R2 = 0.19). The abundance of hornbills, the presence of elephants and percentage forest cover were positively associated with mean seed length of the regenerating cohort (R2 = 0.13). Spatially explicit analysis indicated that some additional processes have an important influence on these response indices. Primates would seem to have a preponderant role for maintaining relatively high species richness, while hornbills and elephant would seem to be predominantly responsible for the recruitment of large-seeded trees. Our results could indicate that these taxa of frugivores play complementary functional roles for forest regeneration. This suggests that the extirpation of one or more of these dispersers would likely not be functionally compensated for by the remaining taxa, hence possibly cascading into compositional shifts.


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