Changes in seed rain during secondary succession in a tropical montane cloud forest region in Oaxaca, Mexico

AbstractSeed dispersal is the first stage of colonization, and potentially affects recruitment. This process deserves more attention in tropical montane cloud forests (TMCF), since secondary succession is common owing to episodic disturbances. We studied annual seed rain in 10 nearby forest stands, ≈7 to ≈100 y following shifting agriculture, and one primary forest stand in southern Mexico to test the hypothesis that seed rain is limited at the scale of neighbouring fragments and that such limitation differs among species with different dispersal modes and successional origin. Annual seed rain was heterogeneous among forest fragments probably due to the prevalence of local seed dispersal, differences in stand age and the proportion of zoochory, and may help explain the patchy distribution of species observed in TMCF. Seed rain abundance and species diversity per unit trap area increased with the age of the stand. Biotically dispersed seeds increased towards older stands relative to abiotically dispersed seeds. Late-successional seeds were rarer in early successional stands than pioneer seeds in late-successional stands, suggesting that long-distance dispersal is generally more common for pioneer plants. Seed dispersal appears to constrain forest regeneration and to influence fragment species composition as a function of the distance from the source forests.

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Influence of Long-Distance Seed Dispersal on the Genetic Diversity of Seed Rain in Fragmented Pinus densiflora Populations Relative to Pollen-Mediated Gene Flow

Journal of Heredity ◽

10.1093/jhered/est022 ◽

2013 ◽

Vol 104 (4) ◽

pp. 465-475 ◽

Cited By ~ 5

Author(s):

H. Ozawa ◽

A. Watanabe ◽

K. Uchiyama ◽

Y. Saito ◽

Y. Ide

Keyword(s):

Genetic Diversity ◽

Gene Flow ◽

Seed Dispersal ◽

Pinus Densiflora ◽

Seed Rain ◽

Long Distance

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Distance effect from cloud forest fragments on plant community structure in abandoned pastures in Veracruz, Mexico

Journal of Tropical Ecology ◽

10.1017/s0266467406003221 ◽

2006 ◽

Vol 22 (4) ◽

pp. 431-440 ◽

Cited By ~ 53

Author(s):

Miguel Angel Muñiz-Castro ◽

Guadalupe Williams-Linera ◽

José María Rey Benayas

Keyword(s):

Species Richness ◽

Vegetation Structure ◽

Forest Restoration ◽

Cloud Forest ◽

Distance Effect ◽

Basal Area ◽

Woody Species ◽

Primary Forest ◽

Forest Fragments ◽

Forest Region

Secondary succession was studied in a Mexican cloud forest region along a chronosequence of 15 abandoned pastures (0.25–80 y). Our objective was to determine the effects of distance from the forest border on successional vegetation structure and woody species richness along the chronosequence. Vegetation structure similar to that of mature forests recovered over 40–50 y, both close to (0–10 m) and away from (40–50 m) the border. Total woody species richness was similar for both distances but species composition differed significantly. When primary forest species were analysed separately, basal area, height, abundance and richness were all significantly higher close to the forest border. Primary species such as Quercus spp. (barochorous-synzoochorous) and Carpinus caroliniana (anemochorous) had lower basal area, density and height away from the border than close to it. Secondary species such as Lippia myriocephala (anemochorous) and Myrsine coriacea (endozoochorous) did not differ in their rate of colonization between distances. The limitation of seed dispersal and establishment for primary woody species away from forest borders suggests that propagules need to be introduced to accelerate forest restoration.

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Determinism and stochasticity in seed dispersal-successional feedbacks

10.1101/791988 ◽

2019 ◽

Author(s):

Nohemi Huanca Nuñez ◽

Robin L. Chazdon ◽

Sabrina E. Russo

Keyword(s):

Community Structure ◽

Seed Dispersal ◽

Secondary Forest ◽

Seed Rain ◽

Secondary Forests ◽

Forest Fragments ◽

Mature Forest ◽

Site Variation ◽

Tropical Secondary Forest ◽

Successional Age

AbstractRegeneration of tropical secondary forests depends critically on seed input, and yet successional dynamics of seed dispersal remain poorly understood. We investigated the role of stochastic vs. deterministic processes in structuring seed rain in successional forests using four years of seed rain data collected at two time periods in four tropical secondary forest fragments representing a chronosequence and in mature forest. Determinism in successional trajectories is defined as predictable, directional, and orderly changes in community structure through time, resulting in convergence toward a climax community. We found that with increasing successional age, the community assembly of the seed rain in secondary forests became more deterministic, and community structure converged to that in the mature forest, both in terms of taxonomic and functional composition. Taxonomic similarity of the seed rain in successional forest to that of the mature forest increased with successional age, as did species co-occurrence and the percentage of shared species between the seed rain of successional and mature forests. The proportions of large, shade-tolerant species in the seed rain increased with successional age, although the proportion of animal-dispersed species increased only modestly. Analyses of the spatial variation in community structure in the seed rain among sites within each secondary forest showed evidence that assembly processes transitioned from being deterministic and convergent early on, to purely stochastic, and then to deterministic and divergent later in succession. Moreover, with increasing successional age, the composition of the seed rain became more similar to that of the mature woody stems in the forest, which could be an important deterministic driver of successional change, that, along with among site variation in landscape context and environment, could also generate idiosyncratic successional patterns among secondary forest fragments Our results suggest that the dominant processes influencing seed dispersal and assembly of the seed rain change during succession and point to successional feedbacks influencing the seed rain that are likely to shape regeneration trajectories.

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The role of frugivorous birds and bats in the colonization of cloud forest plant species in burned areas in western Mexico

Animal Biodiversity and Conservation ◽

10.32800/abc.2015.38.0175 ◽

2015 ◽

Vol 38 (2) ◽

pp. 175-182

Author(s):

J. Rost ◽

◽

E. J. Jardel–Peláez ◽

J. M. Bas ◽

P. Pons ◽

...

Keyword(s):

Plant Species ◽

Cloud Forest ◽

Seed Rain ◽

Cloud Forests ◽

Long Distance ◽

Forest Patch ◽

Frugivorous Birds ◽

Burned Areas ◽

Western Mexico

The extension of montane cloud forests in western Mexico is threatened by several disturbances that limit their extension. In this study we aim to assess the contribution of birds and bats in the dispersal and colonization of cloud–forest plants in contiguous surface–burned pine forests. We sampled seed rain and sapling establishment over one year in two surface–burned sites, which differed in the size of their closest cloud forest patch. A total of 17 plant species were found, most of which were late–successional trees, shrubs and climbers. Distance influenced the seed rain of only one dispersed taxon (Solanum sp.) and had no effect on the sapling distribution of this or other plants. In turn, marked differences were found between sites, with more seeds dispersed and higher sapling density in the site that was next to the larger cloud forest patch. The role of long–distance dispersers and the existence of seed banks before fire could explain the little importance of distance from seed source on seed dispersal and sapling distribution. Nevertheless, dispersal by birds and bats before or after fire facilitates the regeneration and conservation of cloud forests in disturbed areas formerly occupied by other habitats.

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Post-stripping recolonization of vascular epiphytes in cloud-forest fragments in Mexico

Journal of Tropical Ecology ◽

10.1017/s0266467415000395 ◽

2015 ◽

Vol 31 (6) ◽

pp. 499-508 ◽

Cited By ~ 4

Author(s):

Margoth Acuña-Tarazona ◽

Tarin Toledo-Aceves ◽

Alejandro Flores-Palacios ◽

Vinicio J. Sosa ◽

M. Luisa Martínez

Keyword(s):

Secondary Forest ◽

Cloud Forest ◽

Dominance Rank ◽

Forest Fragments ◽

Southern Mexico ◽

Vascular Epiphytes ◽

Recovery Capacity ◽

Epiphyte Communities ◽

Accumulation Curves ◽

Vascular Epiphyte

Abstract:The response of vascular epiphyte communities following natural or human disturbance has been little studied. Over 5 y, we evaluated the post-stripping recolonization of vascular epiphytes in cloud forest. Vascular epiphytes were experimentally removed from branch and trunk plots (1 m in length) on five trees in two secondary cloud forest fragments in southern Mexico. Similarity between colonizer and established communities was compared in each fragment using a further five trees with no stripping. All seedlings were recorded yearly. Non-vascular epiphyte cover was estimated in each plot. The recolonization rate was very high; after 5 y, epiphyte density of the colonizer community (27.4 ± 6.8 individuals per segment) reached similar values to those of the established community (26.7 ± 3.3) in nearby trees. While similarity (composition and abundance) between the colonizer community and established community was high (81%), diversity accumulation curves indicated that the colonizer community presents a lower diversity of epiphytes (5.5 equivalent species) than the established community (11.4). Colonization of xerophytic bromeliads was high, while pteridophytes and orchids presented reduced recovery. The immediately surrounding source of propagules had a strong influence on recolonization. In both the colonizer and established communities, dominance rank was bromeliads > peperomias > pteridophytes. The results show that the recovery capacity of epiphytic vegetation in secondary forest is high, if propagule sources are close by. However, at 5 y after disturbance, it is unclear whether the colonizer community would present the same species composition as the established community or if it would give rise to a different community.

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Below-ground secondary succession in tropical forests of Borneo

Journal of Tropical Ecology ◽

10.1017/s0266467411000149 ◽

2011 ◽

Vol 27 (4) ◽

pp. 413-420 ◽

Cited By ~ 17

Author(s):

Francis Q. Brearley

Keyword(s):

Secondary Succession ◽

Fine Root ◽

Soil Nutrient ◽

Nutrient Status ◽

Stand Age ◽

Primary Forest ◽

Root Mass ◽

Soil Nutrient Status ◽

Lowland Forests ◽

Below Ground

Abstract:As the destruction and severe disturbance of primary tropical forest continues, it is important to understand how these forests may recover from perturbations. Considerable work has been done on above-ground recovery but below-ground processes are less well understood. To determine changes in root mass during tropical secondary succession in lowland forests of Central Borneo, samples were taken from stands of increasing ages since abandonment of agriculture (1, 3, 14 and 31 y) with a primary forest control (six plots from 1-y-old stands and three from all other ages). Root mass and elemental concentrations were determined and soils were chemically analysed. There was no increase in root mass with stand age for fine-root (< 2 mm diameter) or small-root (< 5 mm diameter) mass but there was a trend for coarse-root mass (5–10 mm diameter) to increase with stand age. Negative correlations were shown between root mass and soil nutrient status. Fine-root C concentrations increased with stand age but there was no clear effect of stand age on fine-root N or P. Fine-root mass did not increase significantly with stand age suggesting a rapid recovery; instead, soil nutrient status appeared to be the most important factor controlling root mass. Of the soil nutrients measured in this study, N had a stronger control over root mass than P suggesting that this element may be limiting during secondary succession in tropical lowland forests of Borneo.

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Parent-parent and parent-offspring distances inSpondias radlkoferiseeds suggest long-distance pollen and seed dispersal: evidence from latrines of the spider monkey

Journal of Tropical Ecology ◽

10.1017/s0266467417000050 ◽

2017 ◽

Vol 33 (2) ◽

pp. 95-106 ◽

Cited By ~ 4

Author(s):

Víctor Arroyo-Rodríguez ◽

Esther Aguilar-Barajas ◽

Arturo González-Zamora ◽

Víctor Rocha-Ramírez ◽

Antonio González-Rodríguez ◽

...

Keyword(s):

Seed Dispersal ◽

Spider Monkey ◽

Parental Origin ◽

Forest Fragments ◽

Forest Types ◽

Long Distance ◽

Ecological Processes ◽

Adult Trees ◽

Pollen And Seed Dispersal ◽

Dispersal Distances

Abstract:Pollen and seed dispersal are key ecological processes, directly impacting the spatial distribution, abundance and genetic structure of plant populations; yet, pollen- and seed-dispersal distances are poorly known. We used molecular markers to identify the parental origin (n = 152 adult trees) of 177Spondias radlkoferi(Anacardiaceae) seeds deposited by the spider monkey (Ateles geoffroyi) in latrines located beneath 17 sleeping-trees in two continuous forest sites (CF) and two forest fragments (FF) in the Lacandona rain forest, Mexico. We estimated mean parent-offspring (PO) distances per latrine and, for those seeds (54% of seeds) with more than one candidate parent (i.e. the potential maternal and parental parents), we also estimated parent-parent (PP) distances per latrine, and tested if PO and PP distances differed between forest types. Global PO and PP distances per latrine averaged 682 m (range = 83–1741 m) and 610 m (range = 74–2339 m), respectively, and did not differ significantly between CF and FF. This suggests that pollen dispersal is extensive in both forest types and that long seed dispersal distances (>100 m) are common, thus supporting the hypothesis that the spider monkey is an effective seed disperser ofS. radlkoferiin continuous and fragmented forests.

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Conservation status of the littoral forest of south-eastern Madagascar: a review

Oryx ◽

10.1017/s0030605306000111 ◽

2006 ◽

Vol 40 (1) ◽

pp. 57-66 ◽

Cited By ~ 25

Author(s):

An Bollen ◽

Giuseppe Donati

Keyword(s):

Seed Dispersal ◽

Conservation Status ◽

Forest Fragments ◽

Endemic Plant ◽

Long Distance ◽

Littoral Forest ◽

Plant Animal Interactions ◽

Conservation Plans ◽

Near Future

The littoral forest of the Fort Dauphin region of south-east Madagascar is expected to lose numerous endemic plant and animal species in the near future as a result of deforestation and consequent habitat changes. The disruption of plant-animal interactions is of particular concern. This review describes the conservation status of the littoral forest of Sainte Luce, Fort Dauphin, and examines the role of animal-facilitated seed dispersal in regeneration. The main threats to this habitat are described and possible management implications are discussed in relation to existing initiatives. Protection of the largest remaining forest fragments has been agreed by local communities and a draft plan for forest management is currently under evaluation. Over the next few years plantations will be created to provide local people with wood for fuel and other purposes. An important flying fox Pteropus rufus roost site needs to be included in conservation plans because of its importance for long-distance seed dispersal. Despite the presence of natural barriers, the creation of forest corridors will be crucial for connecting isolated fragments and facilitating genetic exchange between subpopulations. Increased attention needs to be given to the need to promote conservation-related income activities.

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How does the functional diversity of frugivorous birds shape the spatial pattern of seed dispersal? A case study in a relict plant species

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2015.0280 ◽

2016 ◽

Vol 371 (1694) ◽

pp. 20150280 ◽

Cited By ~ 12

Author(s):

Jessica E. Lavabre ◽

Luis J. Gilarranz ◽

Miguel A. Fortuna ◽

Jordi Bascompte

Keyword(s):

Seed Dispersal ◽

Spatial Pattern ◽

Functional Diversity ◽

Seed Rain ◽

Local Network ◽

Modular Organization ◽

Long Distance ◽

Frugivorous Birds ◽

Dispersal Events

Genetic markers used in combination with network analysis can characterize the fine spatial pattern of seed dispersal and assess the differential contribution of dispersers. As a case study, we focus on the seed dispersal service provided by a small guild of frugivorous birds to the common yew, Taxus baccata L., in southern Spain. We build the spatial networks of seed dispersal events between trees and seed-plots within the studied population—local network—and the spatial network that includes all dispersal events—regional network. Such networks are structured in well-defined modules, i.e. groups of tightly connected mother trees and seed-plots. Neither geographical distance, nor microhabitat type explained this modular structure, but when long-distance dispersal events are incorporated in the network it shows a relative increase in overall modularity. Independent field observations suggested the co-occurrence of two complementary groups, short- and long-distance dispersers, mostly contributing to the local and regional seed rain, respectively. The main long-distance disperser at our site, Turdus viscivorus , preferentially visits the most productive trees, thus shaping the seed rain at the landscape scale and affecting the local modular organization. We end by discussing how DNA barcoding could serve to better quantify the role of functional diversity.

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