Seed Banks in Savanna, Forest Fragments, and Continuous Forest Edges Differ in a Tropical Dry Forest in Madagascar

Abstract:Few reports have described the relationship between the distribution of frugivorous birds and vegetation successional changes in dry forests. We assessed the abundance and behaviour of frugivorous birds in early, intermediate and mature dry forests in the Balsas river basin, Guerrero, Mexico. We selected nine dry-forest fragments, three fragments per stage, in these three stages of succession. We analysed the vegetation, estimated bird abundances in 10-min count periods, and recorded the way birds process fruits in circular plots (11–15 plots per fragment, 123 plots in total). Birds were classified as seed predators (15% of all individuals in this study), pulp consumers (15%) or legitimate dispersers (70%). Bird abundance was higher in mature forests in the dry season, while abundance and richness of legitimate dispersers and seed predators were positively related to vegetation complexity. Mature forests have a high vegetation complexity and a high cover ofBurseraspecies that produce fruit during the dry season. During the rains, abundance was higher in early-successional sites when the zoochorous plants produced fruit. Legitimate disperser migrants (i.e.Tyrannus vociferans, Myiarchus cinerascensandM. tyrannulus) were widespread, helping the establishment of zoochorous trees such asBurseraspp. in early-successional forests.

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Influence of matrix type on tree community assemblages along tropical dry forest edges

American Journal of Botany ◽

10.3732/ajb.1300396 ◽

2014 ◽

Vol 101 (5) ◽

pp. 820-829 ◽

Cited By ~ 14

Author(s):

Julieta Benítez-Malvido ◽

Julio César Gallardo-Vásquez ◽

Mariana Y. Alvarez-Añorve ◽

Luis Daniel Avila-Cabadilla

Keyword(s):

Tropical Dry Forest ◽

Dry Forest ◽

Forest Edges ◽

Matrix Type ◽

Tree Community ◽

Community Assemblages

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High density of white-faced capuchins (Cebus capucinus) and habitat quality in the Taboga Forest of Costa Rica

10.1101/692293 ◽

2019 ◽

Author(s):

Elizabeth Tinsley Johnson ◽

Marcela E. Benítez ◽

Alexander Fuentes ◽

Celia R. McLean ◽

Ariek B. Norford ◽

...

Keyword(s):

Costa Rica ◽

Anthropogenic Disturbance ◽

Tropical Dry Forest ◽

Cebus Capucinus ◽

High Density ◽

Dry Forest ◽

Primate Species ◽

Tropical Dry Forests ◽

Forest Fragments ◽

Key Resources

ABSTRACTAcross the globe, primate species and habitats are threatened by human activity. This is especially true for species found in tropical dry forests, which are widely distributed and comprise diverse habitats that remain largely unprotected. Evidence suggests that some primate species endemic to tropical dry forests may be more sensitive to anthropogenic disturbance than others, but our ability to predict primate abundance in the face of disturbance also depends on the specific variables for each site. Here, we consider the factors that explain the high density of white-faced capuchins (Cebus capucinus) found in the Taboga Forest, Costa Rica, a relatively small fragment of tropical dry forest surrounded by agricultural fields. Our analyses suggest that, for capuchins (and potentially for mantled howler monkeys, Alouatta palliata), the size and disturbance of a forest fragment may matter less than the composition and availability of key resources, like above-ground water. Group sightings for both species were higher near permanent water sources, but group sightings did not vary between edge and interior forest. These findings help explain why some primate species can flourish even alongside anthropogenic disturbance and thus carry important implications for conservation efforts. Smaller forest fragments, like Taboga, may be able to support high densities of some species because they provide a mosaic of habitats and key resources that buffer adverse ecological conditions. Future studies will assess the extent to which primates in the Taboga Forest rely on the canals versus the river and will consider how the high density of capuchins in Taboga influences ranging patterns, home range overlap, and the frequency and intensity of intergroup encounters.RESEARCH HIGHLIGHTSHere we introduce a new white-faced capuchin study site in the Taboga Forest, Costa Rica, a fragmented tropical dry forest.Forest fragments like Taboga may support high primate densities because they provide a mosaic of habitats and key resources.

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A new species of the armored spider genus Caraimatta Lehtinen, 1981 from Colombia (Araneae: Synspermiata: Tetrablemmidae)

Zootaxa ◽

10.11646/zootaxa.4619.1.8 ◽

2019 ◽

Vol 4619 (1) ◽

pp. 168-176

Author(s):

ANDRÉS F. GARCÍA ◽

LEONEL MARTÍNEZ ◽

DANIELA AHUMADA-C

Keyword(s):

New Species ◽

Tropical Dry Forest ◽

First Record ◽

Identification Key ◽

Dry Forest ◽

Forest Fragments ◽

Male And Female ◽

Males And Females ◽

A New Species

A new species of the armored spider genus Caraimatta Lehtinen, 1981 from Colombian Tropical dry forest fragments is described and illustrated: Caraimatta brescoviti sp. nov. (based on male and female) from Bolivar and Sucre departments, representing the first record of the genus from Colombia. Additionally, photographs of Monoblemma muchmorei Shear, 1978 (other tetrablemmid species previously recorded from the country) are given. A map with the known distribution and an identification key for males and females of the Caraimatta species are also included.

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Nonconstituent species in soil seed banks as indicators of anthropogenic disturbance in forest fragments

Canadian Journal of Forest Research ◽

10.1139/x06-137 ◽

2006 ◽

Vol 36 (9) ◽

pp. 2300-2316 ◽

Cited By ~ 8

Author(s):

Luxiang Lin ◽

Min Cao ◽

Yongtao He ◽

Jerry M Baskin ◽

Carol C Baskin

Keyword(s):

Forest Fragmentation ◽

Forest Ecosystems ◽

Biological Diversity ◽

Seed Banks ◽

Soil Samples ◽

Southwestern China ◽

Native Forest ◽

Forest Fragments ◽

Soil Seed Banks ◽

Continuous Forest

Forest fragmentation is prevalent in regions with high human population density, but also with high biological diversity, such as southwestern China. Predicting potential changes in species composition in native forest ecosystems resulting from forest fragmentation is an important approach in assessing forest ecosystems and sustainable management of forests. The term nonconstituent species is proposed for plant species that occur in a natural landscape but are not native to it. We hypothesized that fragmentation of continuous forests significantly increases both the richness and the size of soil seed banks of nonconstituent species. To test our hypothesis we compared soil seed banks in three small fragments and one large tract of subtropical evergreen broad-leaved forest in Yunnan Province, southwestern China. In total, 249 species were identified in all soil samples from the four sites. Nonconstituent species represented 36.4%–61.5% of the total taxa and 33.8%–59.6% of total germinants from soil samples in the three forest fragments, but only 3.7%–7.9% of total taxa and 7.5%–9.4% of total germinants from soil samples in the continuous forest tract. Both richness and size of soil seed banks of nonconstituent species were greater under forest fragments than under continuous forest. A majority of nonconstituent species were native weeds and annual herbs with wind-dispersed seeds; most were present in soil seed banks but not in aboveground vegetation. We suggest that nonconstituent species in soil seed banks could be used as an indicator species group for assessing human disturbance. If so, the richness and size of soil seed banks of nonconstituent species could play an important role in quantifying disturbance in forests.

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Edaphic and Seasonal Heterogeneity of Seed Banks in Agricultural Fields of a Tropical Dry Forest Region in Southern Mexico

Botanical Sciences ◽

10.17129/botsci.393 ◽

2012 ◽

Vol 90 (3) ◽

pp. 287 ◽

Cited By ~ 5

Author(s):

Jorge A. Meave ◽

Claudia Flores-Rodríguez ◽

Eduardo A. Pérez-García ◽

Marco Antonio Romero-Romero

Keyword(s):

Seed Bank ◽

Tropical Dry Forest ◽

Abundant Species ◽

Black Soil ◽

Seed Banks ◽

Dry Forest ◽

Agricultural Fields ◽

Tropical Region ◽

Soil Cores ◽

Southern Mexico

The slash-and-burn agriculture practiced across tropical dry regions results in the elimination of native vegetation. Upon field abandonment, the seed bank becomes a potentially important mechanism of natural regeneration at early successional stages. Soil properties and climate seasonality may affect seed bank characteristics, thus we analyzed the effects of these two factors on seed bank density and composition in agricultural fields of a seasonally dry tropical region of southern Mexico. Soil cores were collected for the rainy and the dry seasons in order to assess changes occurring in the seed bank from the time of harvest to the moment when succession could potentially start (the next rainy season). The 12 studied fields comprised three different soil types recognized by local inhabitants: sandy and stony, silty, and clayey soils, locally known as cascajo, black soil, and red soil, respectively. At each fi eld 20 soil cores (8 cm diameter, 4.5 cm depth) were collected and mixed to form four pooled samples, which were placed in a greenhouse to induce germination. A total of 4,422 seedlings (2,291 seeds m-2) representing 40 species were recorded. The most abundant species were, in decreasing order, Melanthera nivea, Rhynchelytrum repens, Waltheria indica, Amaranthus scariosus, Digitaria bicornis, and Cenchrus pilosus. Herbs were the prevailing growth form (> 80% of total richness). No clear pattern was observed in the seed bank related to soil type; however, seed bank characteristics tended to be associated with the time of use of the agricultural fields, a variable that was not controlled in the study. Seed bank species richness was significantly larger in the dry season, and although seed density showed a similar trend, it was not significant. The studied seed banks contain no elements of the regional primary tropical dry forest, which suggests that seed banks in deforested areas cannot guarantee their maintenance beyond forested areas.

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A new species of Capparidastrum (Capparaceae Juss.) from the Cauca inter Andean valley of Colombia

Phytotaxa ◽

10.11646/phytotaxa.439.3.9 ◽

2020 ◽

Vol 439 (3) ◽

pp. 276-286

Author(s):

JORGE D. MERCADO-GÓMEZ ◽

MARÍA EUGENIA MORALES-PUENTES

Keyword(s):

New Species ◽

Tropical Dry Forest ◽

Dry Forest ◽

Forest Fragments ◽

Santa Fe ◽

Biogeographic Province ◽

A New Species

We describe and illustrate a new species of Capparidastrum subgen. Pulviniglans (Capparaceae). Capparidastrum dugandii occurs in tropical dry forest fragments of the Colombian inter-Andean valley of the Dagua River, near the municipality of Santa Fe de Antioquia. Capparidastrum dugandii is distinguished from other species of subgen. Pulviniglans molecularly and by the lowest number of stamens (18–20). In addition, the species is endemic to the Cauca biogeographic province.

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Effects of disturbance and altitude on soil seed banks of tropical montane forests

Journal of Tropical Ecology ◽

10.1017/s0266467413000667 ◽

2013 ◽

Vol 29 (6) ◽

pp. 523-529 ◽

Cited By ~ 7

Author(s):

Denis Lippok ◽

Florian Walter ◽

Isabell Hensen ◽

Stephan G. Beck ◽

Matthias Schleuning

Keyword(s):

Species Richness ◽

Tropical Forests ◽

Species Turnover ◽

Habitat Type ◽

Seed Banks ◽

Seed Density ◽

Forest Fragments ◽

Forest Edges ◽

Soil Seed Banks ◽

Forest Remnants

Abstract:Vast areas of tropical forests have been deforested by human activities, resulting in landscapes comprising forest fragments in matrices of deforested habitats. Soil seed banks (SSB) are essential sources for the regeneration of tropical forests after disturbance. In a fragmented montane landscape in the Bolivian Andes, we investigated SSB in three different habitat types that were associated with different degrees of disturbance, i.e. in forest interior, at forest edges and in deforested habitats. Sampling of habitats was replicated at six sites ranging in altitude from 1950 to 2450 m asl. We extracted seeds from dried soil samples by sieving, classified seeds into morphospecies and size classes, and characterized SSB in terms of density, species richness and composition. We tested effects of disturbance (i.e. habitat type) and altitude on SSB characteristics. Overall, small seeds (<1 mm) dominated SSB (81% of sampled seeds). Seed density and species richness were lowest in deforested habitats, especially in large seeds and distant from adjacent forests (≥20 m), while small-seeded species were most numerous near forest margins. Species turnover between habitats was high. Altitude altered the composition of SSB, but had no effects on seed density and species richness. We conclude that the potential of SSB for natural regeneration of deforested habitats is low and decreases with increasing distance from forest remnants and that forest edges may be eventually invaded by small-seeded species from deforested habitats.

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