Weedy and secundary palm species in central amazonian forest Fragments

Forest fragmentation may affect the abundance and distribution of organisms. Some species populations decrease being eventually driven to local extinction while other species may experience population increase. In a survey of the composition and abundance of secondary and weedy palms in eight forest fragments (three of 1-, three of 10- and two of 100-ha), in three sites (Dimona, Porto Alegre and Esteio) in central Amazonia, five native palm species which do not occur in the continuous forest were identified. Three were secondary species (Astrocaryum acaule Mart., Bactris maraja Mart. var. maraja and Bactris sp), one weedy (Lepidocaryum tenue Mart.), and one of unknown status (B. oligocarpa Barb. Rodr. & Trail). The highest abundance was found in the 1-ha fragments which had 172 of the 206 palms found compared with 33 in the 10-ha and one in the 100-ha fragments. However, most of these palms occur in the Dimona site, which accounted for 195 of the 206 of the individuals, compared with seven in Esteio and four in Porto Alegre. The weedy L. tenue, which forms clonal populations, although occurring only in Dimona, accounted for 91% of the individuals recorded. It is possible that with increased habitat degradation of small fragments, some populations of secondary and weedy species will also increase, what may be detrimental to the closed forest plant species populations occurring in forest fragments.

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EXOTIC PALMS THREATENS NATIVE PALMS: A RISK TO PLANT BIODIVERSITY OF ATLANTIC FOREST

Revista Árvore ◽

10.1590/1806-90882018000200016 ◽

2018 ◽

Vol 42 (2) ◽

Author(s):

Tiago Monteiro Condé ◽

Fernando da Silva ◽

Agostinho Lopes de Souza ◽

Helio Garcia Leite ◽

Eder Aparecido Garcia ◽

...

Keyword(s):

Atlantic Forest ◽

Secondary Forest ◽

Control Measures ◽

Anthropogenic Pressure ◽

Forest Fragments ◽

Palm Trees ◽

Continuous Forest ◽

High Germination ◽

Palm Species ◽

Forest Strata

ABSTRACT Invasive plants can profoundly modify physical and biological characteristics of their new environments, especially when such habitats are already fragmented and reduced by anthropogenic pressure, such as the Atlantic Forest of Brazil. Here, we hypothesized that exotic palms successfully establish among the natural Euterpe edulis populations through a continuous propagule input by avifauna, high germination rates, and rapid growth. As a result, the native palm is experiencing decline and may be threatened with extinction. Beginning in 2007, we conducted a continuous forest inventory (FCI) every three years in the primary and secondary forest fragments of Viçosa, Minas Gerais. We use a Markov matrix to project future distributions of palm trees. The secondary forest contained three exotic palm species: Archontophoenix alexandrae, Livistona chinensis, and Arenga caudata. The first palm is a serious risk to natural E. edulis populations in the Atlantic because of frequent interactions with birds, rapid germination, and aggressive colonization in the lower to medium vertical forest strata. Currently, natural E. edulis populations are viable and sustainable, capable of regeneration, growth, and fruiting, their communities maintain continuous gene flow, dominating vertical forest strata compared with exotic palms. However, exotic palms should be monitored and control measures should be analyzed, especially in areas with A. alexandrae populations.

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Long Term Interactions of Native and Invasive Species in a Marine Protected Area Suggest Complex Cascading Effects Challenging Conservation Outcomes

Diversity ◽

10.3390/d13020071 ◽

2021 ◽

Vol 13 (2) ◽

pp. 71

Author(s):

Charalampos Dimitriadis ◽

Ivoni Fournari-Konstantinidou ◽

Laurent Sourbès ◽

Drosos Koutsoubas ◽

Stelios Katsanevakis

Keyword(s):

Invasive Species ◽

Native Species ◽

High Performance ◽

Marine Protected Area ◽

Habitat Degradation ◽

Population Increase ◽

Rocky Reef ◽

Cascading Effects ◽

High Level

Understanding the interactions among invasive species, native species and marine protected areas (MPAs), and the long-term regime shifts in MPAs is receiving increased attention, since biological invasions can alter the structure and functioning of the protected ecosystems and challenge conservation efforts. Here we found evidence of marked modifications in the rocky reef associated biota in a Mediterranean MPA from 2009 to 2019 through visual census surveys, due to the presence of invasive species altering the structure of the ecosystem and triggering complex cascading effects on the long term. Low levels of the populations of native high-level predators were accompanied by the population increase and high performance of both native and invasive fish herbivores. Subsequently the overgrazing and habitat degradation resulted in cascading effects towards the diminishing of the native and invasive invertebrate grazers and omnivorous benthic species. Our study represents a good showcase of how invasive species can coexist or exclude native biota and at the same time regulate or out-compete other established invaders and native species.

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The persistence of ant-following birds in small amazonian forest fragments

Acta Amazonica ◽

10.1590/1809-43921989191263 ◽

1989 ◽

Vol 19 (0) ◽

pp. 249-263 ◽

Cited By ~ 41

Author(s):

Lee H. Harper

Keyword(s):

Forest Fragments ◽

Ant Colonies ◽

Amazonian Forest ◽

Army Ant ◽

Continuous Forest ◽

Introduced Birds ◽

Small Forest

SUMMARYMist-net captures of army ant-following bird were monitored during the isolation of central Amazonian forest fragments of 1 ha (n = 5), 10 ha (n = 4) and 100 ha (n = 1). Post-isolation captures of the three obligate ant-following birds Dendrocinela merula, Pithys albifrons, and Gymnopithys rufigula decreased significantly in all fragments. post-isolation captures of four facultative ant-following species were not significantly different in forest fragments of 1 ha and 10 ha, although two species decreased significantly in the 100 ha fragment. Experimental introductions of obligate species into small forest fragments in the absence and presence of introduced Eciton burchelli army ant colonies resulted in significantly greater recaptures of introduced birds when active army ant colonies were present. Of the 105 birds introduced, 58 ' 55%) crossed 100-320 m od dedorested area an were recaptured in continuous forest.

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Distribution of Atta (Hymenoptera - Formicidae) in "terra-firme" rain forest of Central Amazonia: density, species composition and preliminary results on effects of forest fragmentation

Acta Amazonica ◽

10.1590/1809-43921988183315 ◽

1988 ◽

Vol 18 (3-4) ◽

pp. 309-315 ◽

Cited By ~ 14

Author(s):

Heraldo Luís de Vasconcelos

Keyword(s):

Species Composition ◽

Rain Forest ◽

Abundant Species ◽

Forest Fragments ◽

Forest Fragment ◽

Terra Firme ◽

Atta Sexdens ◽

Conservation Areas ◽

Continuous Forest ◽

Leaf Cutting

One hundred and fourteen hectares of a "terra-fiirme" rain forest 70 km north of Manaus, Amazonas, Brazil, were surveyed for leaf-cutting ant colonies (Atta spp). One half of this area was in isolated forest fragments (surrounded by pastures or second growth) of two sizes: 1 and 10 ha. The other half was in non-isolated fragments (connected to a large parch of forest) of the same sizes. Only two species occured in this forest: Atta sexdens sexdens L. and A. cepfhalotes L. The first was the most abundant species with a mean density of 0.35 colonies per ha. The mean density of A. cephalotes colonies was 0.03 per ha. The density of colonies was not significantly different between the isolated fragments and the continuous forest. Furthermore, the species composition did not change with isolation. However, pre-isolation data and long term monitoring are necessary to conclude that the isolation of a forest fragment has no effect upon Atta colonies. The non-uniform spatial distribution of Atta colonics within the "terra-firme" forest must be taken into account when selecting conservation areas in the Amazon, in order to preserve this important group of ants together with their native habitat.

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Recover and They’ll Come: Flower Visiting Bees Benefit from the Continuous of Micro-Environments Set by Regenerating Forest Fragments

Sociobiology ◽

10.13102/sociobiology.v68i1.5861 ◽

2021 ◽

Vol 68 (1) ◽

pp. 5861

Author(s):

Ana Isabel Sobreiro ◽

Lucas Lopes da Silveira Peres ◽

Jessica Amaral Henrique ◽

Rosilda Mara Mussury ◽

Valter Vieira Alves-Junior

Keyword(s):

Urban Areas ◽

Environmental Changes ◽

Climatic Conditions ◽

Agricultural Activity ◽

Forest Fragments ◽

Forest Types ◽

Continuous Forest ◽

Flower Visiting ◽

Bee Communities ◽

Forest Habitats

Forest habitats are important sources of food and nesting resources for pollinators, primarily in urban areas and landscapes with intense agricultural activity. The forest fragmentation and environmental changes occurring in these green refuges are known to impose survival challenges to pollinating bees, leading to species loss. However, it is not well known how the species of bees that visit flowers are distributed in forest micro-environments. To fill this gap, we sampled flower visiting bees in a continuous forest matrix with micro-environments of two forest types (mature and regenerating forest). We examined how the local environmental changes and climatic conditions affect the composition and uniformity of bee communities in the different micro-environments. Our results indicated that both abundance and richness were similar between forest types studied here, however climatic conditions and plant flowering patterns affect the composition of bees. Thus, our results demonstrated that the continuous micro-environments can favor floral visits and the reintegration of bee communities, and still, that this strategy can be used to minimize the impacts of environmental changes at local scales.

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Primate populations in continuous forest and forest fragments in Central Amazonia

Acta Amazonica ◽

10.1590/1809-43921988183307 ◽

1988 ◽

Vol 18 (3-4) ◽

pp. 291-307 ◽

Cited By ~ 59

Author(s):

Anthony B. Rylands ◽

Alexine Keuroghlian

Keyword(s):

Food Sources ◽

Primate Species ◽

Forest Fragments ◽

The Past ◽

Pithecia Pithecia ◽

Ateles Paniscus ◽

Continuous Forest ◽

Second Growth ◽

Central Amazonia ◽

One Year

Population densities of six primate species (Saguinus midas, Pithecia pithecia, Cebus apella, Chiropotes satanas, Alouatta seniculus and Ateles paniscus) were estimated in continuous forest and in isolated reserves (one of 100 ha and four of 10 ha). Saguinusdensities in the continuous forest were found to be low, probably due to the lack of edge habitat and second growth favoured by them; Pithecia, Cebus and Ateles populations are also low, possibly because of more widely distributed and/or less abundant food sources than is true for other Amazonian regions, although hunting in the past, particularly of Ateles may also be a contributing factor; and Chiropotes and Alouatta densities were found to be similar to those observed in other areas of Amazonas forests. Ateles and Chiropotes, which occupy ranges on the order of three km2 were excluded from the 100-ka reserve at the time of its isolation. Unfortunately populations were not known prior to isolation of this reserve but during isolation there remained four groups of Saguinus, two Pitheciagroups, one Cebus groups and five Alouatta groups. One Saguinus group disappeared two months later, and one year post-isolation the Cebus group also left the reserve. Single Alouatta groups survive in the isolated 10-ha reserves. Saguinus, present in the four 10-ha reserves following isolation, have disappeared from two of them. One 10-ha reserve retains a group of Pithecia.

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

Biotropica ◽

10.1111/btp.12228 ◽

2015 ◽

Vol 47 (4) ◽

pp. 435-440 ◽

Cited By ~ 4

Author(s):

Kim Valenta ◽

Travis S. Steffens ◽

Radoniaina R. Rafaliarison ◽

Colin A. Chapman ◽

Shawn M. Lehman

Keyword(s):

Tropical Dry Forest ◽

Seed Banks ◽

Dry Forest ◽

Forest Fragments ◽

Forest Edges ◽

Continuous Forest

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Nutrient Enrichment, Sedimentation, Heavy Metals and Plastic Pollution in the Marine Environment and its Implications on Philippine Marine Biodiversity: A Review

IAMURE International Journal of Ecology and Conservation ◽

10.7718/ijec.v15i1.999 ◽

2015 ◽

Vol 15 (1) ◽

Cited By ~ 1

Author(s):

Neil Angelo S. Abreo ◽

Edison D. Macusi ◽

Ginalyn C. Cuenca ◽

Cyril Tom B. Ranara ◽

Michael B. Andam ◽

...

Keyword(s):

Heavy Metals ◽

Food Web ◽

Alien Species ◽

Marine Environment ◽

Nutrient Enrichment ◽

Indirect Effects ◽

Habitat Degradation ◽

Population Increase ◽

Marine Biodiversity ◽

Plastic Pollution

Marine biodiversity plays a vital role in ecosystem resilience and stability against climate change and alien species invasions, among others. This also plays a role in the provision of ecosystem services and functions that benefits humans. However due to anthropogenic activities and population increase, marine biodiversity have been affected most. We conducted a review using open-sourced journals on the effects of nutrient enrichment, sedimentation, heavy metals and plastic pollution in the marine environment and its implications on marine biodiversity. Lethal and sub-lethal effects were observed in different organisms that could affect marine biodiversity directly or indirectly. Direct effects include mortality of organisms while indirect effects include habitat degradation or alteration, a simplified food web, increase alien species invasion and reduced fitness of organisms. Human land use change, coastal construction activities, untreated sewage discharges, pesticides, mine tailings, uncollected, unsegregated and improperly dumped garbages and unabated garbage dumping at sea have been found to negatively influence marine biodiversity. In the Philippines, very few studies have been conducted with regards to marine pollution, especially on marine plastic debris, and even fewer studies have been made that tackles the effect of these stressors at an ecosystem level. Furthermore, this review has identified direct and indirect effects of pollution stressors on marine organisms which include: mortality and reduced fitness, vulnerability to disease or sickness,-habitat degradation, and food web simplification. Keywords - Ecology, nutrient enrichment, sedimentation, plastic, biodiversity, literature review, pollution, Philippines

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Abundance and Distribution of Odonates (Dragonflies and Damselflies) In Akwa Ibom State, Nigeria

Pan African Journal of Life Sciences ◽

10.36108/pajols/8102/10(0160) ◽

2018 ◽

Vol 1 (1) ◽

pp. 33-38

Author(s):

Kehinde A. Kemabonta ◽

Rosemary Essien ◽

Babasola W. Adu ◽

Sylvester U. Ogbogu ◽

Abdussalam Iysa ◽

...

Keyword(s):

Species Diversity ◽

Statistical Difference ◽

Habitat Degradation ◽

Anthropogenic Activities ◽

Ongoing Research ◽

Management Techniques ◽

Study Sites ◽

Abundance And Distribution ◽

Number Of Individuals ◽

Sweep Net

Introduction: Odonates are used as bio-indicators for monitoring habitat degradation both on terrestrial and aquatic ecosystem because of their sensitivity to anthropogenic activities. They serve an important role in the ecological food chain by consuming aquatic larvae and being in turn consumed by birds and various amphibians. This study is part of the ongoing research on the diversity of Odonate species of Nigeria. The objective is to determine the abundance and distribution of odonates in Akwa Ibom State and to compare the species diversity across the various sites in Akwa Ibom State. Methodology: Akwa Ibom state was divided into six areas namely Ikot Akpaden, Obio Akpa, Ikot Okoro, Ikot Udofia, Urua Udofia and Obio Ndot using biotypes and a study site was randomly selected in each area. Adult members were captured using a sweep net and were preserved for identification using morphological features. Results: A total of 767 odonates were collected at the six study sites representing 24 species, 16 genera and four families namely Libellulidae (77%), Coenagrionidae (21%), Calopterygidae (>1%) and Chlorocyphidae (>1%). Most of the species collected were members of family Libellullidae (77%) with Palpopleura lucia having the highest occurrence (41%) and found in all the sites. Family Calopterygidae and Chlorocyphidae had less than 1% population of the total individuals collected. Ikot Okoro had the highest number of individuals (238) and the least evenness (e^H/S=0.3292) while Ikot Akpaden, which had the least effect of anthropogenic intrusion had the largest diversity of Odonata species (H’=2.387). Obio Ndot had the most evenly distributed Odonata species (e^H/S=0.8028). There was no statistical difference in the occurrence of dragonflies across all study sites (p= 0.238). Conclusion: The high occurrence of family Libellulidae which are anthropogenic tolerant, and the absence of more highly localized species indicate that most of the study sites have been degraded and may not be fit for species with narrow niches. It is therefore vital to conserve the Odonata community by implementing proper forest management techniques.

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Reference Site Influences Perceived Species Loss in Shade Coffee, But Assemblages in Fact Depend on Landscape Context

10.21203/rs.3.rs-766613/v1 ◽

2021 ◽

Author(s):

Maria Juliana Bedoya ◽

Harrison H Jones ◽

Kristen Malone ◽

Lyn C Branch

Keyword(s):

Agricultural Landscapes ◽

Camera Traps ◽

Landscape Context ◽

Forest Fragments ◽

Shade Coffee ◽

Coffee Plantations ◽

Fragmented Forest ◽

Continuous Forest ◽

Species Occupancy

Abstract Context: Shade coffee plantations are purported to maintain forest biodiversity in agricultural landscapes. Understanding their conservation importance is hindered, however, by the limited taxa studied and failure to account for the landscape context of plantations and quality of reference sites.Objectives/Research questions: (1) how occupancy of mammals and birds changed from continuous forest to fragmented forest and coffee plantations while statistically controlling for landscape context, and (2) whether mammal and bird communities responded differently to shade coffee with regard to richness and composition.Methods: We used camera traps to sample ground-dwelling birds and medium- and large-bodied mammals (31 and 29 species, respectively) in shade coffee plantations and two types of reference forest (fragmented and continuous) in Colombia’s Western Andes. We used a multi-species occupancy model to correct for detection and to estimate occupancy, richness, and community composition.Results Shade coffee lacked ~50% of the species found in continuous forest, primarily forest-specialist insectivorous birds and forest-specialist and large-bodied mammals, resulting in different species composition between coffee and forest assemblages. Coffee plantation birds were generally a unique subset of disturbance-adapted specialists, whereas mammals in coffee were mostly generalists encountered across land uses. Forest fragments had species richness more similar to shade coffee than to continuous forest. Species sensitive to shade coffee responded negatively to isolation and disturbance at the landscape scale.Conclusions: Studies comparing coffee with relictual forest fragments may overestimate the conservation value of shade coffee. Conservation of biodiversity in shade coffee landscapes will be ineffective unless these efforts are linked to larger landscape-level conservation initiatives.

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