The effect of forest fragments on abundance, diversity and species composition of predatory ants in sugarcane fields

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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A PAISAGEM COMO CONDICIONADORA DE BORDAS DE FRAGMENTOS FLORESTAIS

FLORESTA ◽

10.5380/rf.v35i1.2427 ◽

2005 ◽

Vol 35 (1) ◽

Cited By ~ 7

Author(s):

Bethania Cristiane Herrmann ◽

Efraim Rodrigues ◽

André De Lima

Keyword(s):

Species Composition ◽

Patch Size ◽

Nearest Neighbor ◽

Core Area ◽

Forest Fragments ◽

Spatial Structures ◽

Landscape Index ◽

Area Index ◽

Components Analysis ◽

The Relationship

Fragmentos florestais diferem em sua estrutura espacial afetando a composição de espécies em suas bordas. O objetivo deste trabalho foi analisar a influência dos índices da paisagem sobre as bordas de fragmentos florestais próximos à cidade de Londrina - PR. As características estruturais dos fragmentos aqui consideradas incluem área, forma, área central e índice de área central; e as características estruturais da paisagem: área da classe, tamanho médio e coeficiente de variação do tamanho dos fragmentos de floresta, distância média até o fragmento florestal mais próximo e total de bordas de floresta. A relação entre composição de espécies, fragmentos florestais e índices de paisagem foi estudada através de Análise de Correspondência Canônica. Os índices de maior importância foram: área, forma e área central dos fragmentos. Godoy, fragmento com 2371,14 ha e inclui o Parque Estadual Mata dos Godoy, apresentou maior variação na composição de espécies quando comparado com os demais. The landscape as conditioning of edges of forest fragments Abstract Forests fragments differ in their spatial structure afecting the species composition of edges. The objective of this paper was to analyze the influence of some landscape index over sapling species composition in edges of forests fragments near Londrina - PR. The spatial structures of fragments considered in this paper involved area, shape, core area and core area index; and the spatial structures of landscape: class area, mean patch size, coefficient of variation of the size of the patch (%), mean nearest neighbor distance and total edge of forest. The relationship between sapling species composition, forests fragments and landscape index were evaluated through Principal Components Analysis. Godoy, fragment with 2371,14 ha showed more variation in the species composition when compared with other fragments.

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Frugivorous butterflies in Venezuelan forest fragments: abundance, diversity and the effects of isolation

Journal of Tropical Ecology ◽

10.1017/s0266467499001121 ◽

1999 ◽

Vol 15 (6) ◽

pp. 703-722 ◽

Cited By ~ 44

Author(s):

Ghazala Shahabuddin ◽

John W. Terborgh

Keyword(s):

Species Diversity ◽

Habitat Fragmentation ◽

Species Composition ◽

Dry Season ◽

Butterfly Species ◽

Forest Fragments ◽

Interspecific Differences ◽

Species Responses ◽

Source Populations ◽

Abundance And Diversity

Frugivorous butterflies were studied in a set of forested islands (0.1 to 1.15 ha) in a reservoir in eastern Venezuela to investigate the effects of fragmentation and the resulting isolation on their abundance, diversity and species composition. While some islands showed reduced abundance and species diversity in comparison to unfragmented (or control) sites, others did not. Isolation status affected both butterfly abundance and diversity. Islands located close to their colonizing sources (0.1–1 km) tended to support similar densities of butterflies but lower numbers of species in comparison to control sites. Far fragments (1–3 km from their colonizing sources) tended to harbour lower butterfly densities in comparison to control sites but undiminished numbers of species. Species composition varied significantly between control sites and islands and amongst control sites, near islands and far islands. Interspecific differences were observed in species' responses to fragmentation. Charaxines, medium-sized satyrines, morphines and brassolines may be vulnerable to extinction after habitat fragmentation while small-sized satyrines may be relatively resistant. Observations during the dry season indicate that butterfly species may exist as mainland-island metapopulations in Lago Guri, in which small habitat fragments require recolonization every year from source populations in large islands and mainland habitat.

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Trophic structure stability and extinction dynamics of beetles (Coleoptera) in tropical forest fragments

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1998.0221 ◽

1998 ◽

Vol 353 (1367) ◽

pp. 437-451 ◽

Cited By ~ 114

Author(s):

R. K. Didham ◽

J. H. Lawton ◽

P. M. Hammond ◽

P. Eggleton

Keyword(s):

Species Richness ◽

Species Composition ◽

Tropical Forest ◽

Forest Fragmentation ◽

Trophic Structure ◽

Forest Edge ◽

Forest Fragments ◽

Trophic Groups ◽

Predator Species ◽

Extinction Probabilities

A first analysis of the stability of trophic structure following tropical forest fragmentation was performed in an experimentally fragmented tropical forest landscape in Central Amazonia. A taxonomically and trophically diverse assemblage of 993 species of beetles was sampled from 920 m 2 of leaf litter at 46 sites varying in distance from forest edge and fragment area. Beetle density increased significantly towards the forest edge and showed non-linear changes with fragment area, due to the influx of numerous disturbed-area species into 10 ha and 1 ha fragments. There was a marked change in species composition with both decreasing distance from forest edge and decreasing fragment area, but surprisingly this change in composition was not accompanied by a change in species richness. Rarefied species richness did not vary significantly across any of the sites, indicating that local extinctions of deep forest species were balanced by equivalent colonization rates of disturbed-area species. The change in species composition with fragmentation was non-random across trophic groups. Proportions of predator species and xylophage species changed significantly with distance from forest edge, but no area-dependent changes in proportions of species in trophic groups were observed. Trophic structure was also analysed with respect to proportions of abundance in six trophic groups. Proportions of abundance of all trophic groups except xylomycetophages changed markedly with respect to both distance from forest edge and fragment area. Local extinction probabilities calculated for individual beetle species supported theoretical predictions of the differential susceptibility of higher trophic levels to extinction, and of changes in trophic structure following forest fragmentation. To reduce random effects due to sampling error, only abundant species ( n ≥ 46) were analysed for extinction probabilities, as defined by absence from samples. Of these common species, 27% had significantly higher probabilities of local extinction following fragmentation. The majority of these species were predators; 42% of all abundant predator species were significantly more likely to be absent from samples in forest fragments than in undisturbed forest. These figures are regarded as minimum estimates for the entire beetle assemblage because rarer species will inevitably have higher extinction probabilities. Absolute loss of biodiversity will affect ecosystem process rates, but the differential loss of species from trophic groups will have an even greater destabilizing effect on food web structure and ecosystem function.

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Species composition and floristic relationships in southern Goiás forest enclaves

Rodriguésia ◽

10.1590/2175-7860201162109 ◽

2011 ◽

Vol 62 (1) ◽

pp. 123-137 ◽

Cited By ~ 3

Author(s):

Paulo Oswaldo Garcia ◽

Arthur Sérgio Mouço Valente ◽

Daniel Salgado Pifano ◽

José Felipe Salomão Pessoa ◽

Luiz Carlos Busato ◽

...

Keyword(s):

Species Composition ◽

Human Impacts ◽

Forest Fragments ◽

Generalist Species ◽

Central Brazil ◽

Breast Height ◽

Savanna Vegetation ◽

Tree Community ◽

Analysis Of Similarity ◽

Forest Remnants

Abstract Hinterland fragments of Atlantic forests situated in transitional areas are poorly known with respect to the effectsof human impacts on their species composition and regeneration. The purpose of this study was to describe andcharacterize the structure and composition of the tree community of forest remnants located in Itumbiara, GoiásState, Central Brazil, and to analyze their floristic relationship with other areas of seasonal and transitionalvegetation ecotones. Five forest fragments were chosen for tree community sampling. The survey was carried outusing PCQ (point-centered quarter) method and 25 points were distributed along linear transects totalling 125sampling units. Four live trees with circumference at breast height (1.30 m) > 15 cm were recorded at each point.The floristic and phytosociological surveys recorded 149 tree species belonging to 110 genera and 47 families.The analysis of similarity confirmed the ecotonal character with many generalist species and other with occasionaloccurrence in 'Cerrado' (woody savanna) and seasonal forests. The forest remnants in Itumbiara showed a hightree species diversity. In spite of this, the tree community species suggests higher similarity with savanna vegetation.

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Avian top-down control affects invertebrate herbivory and sapling growth more strongly than overstorey species composition in temperate forest fragments

Forest Ecology and Management ◽

10.1016/j.foreco.2019.03.055 ◽

2019 ◽

Vol 442 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Daan Dekeukeleire ◽

Irene M. van Schrojenstein Lantman ◽

Lionel R. Hertzog ◽

Martijn L. Vandegehuchte ◽

Diederik Strubbe ◽

...

Keyword(s):

Species Composition ◽

Temperate Forest ◽

Forest Fragments ◽

Top Down ◽

Sapling Growth ◽

Invertebrate Herbivory

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Influence of Deforestation on the Community Structure of Sand Flies (Diptera: Psychodidae) in Eastern Amazonia

Journal of Medical Entomology ◽

10.1093/jme/tjz014 ◽

2019 ◽

Vol 56 (4) ◽

pp. 1004-1012

Author(s):

José Manuel Macário Rebêlo ◽

Jorge Luiz Pinto Moraes ◽

Gustavo Barbosa Vieira Cruz ◽

Joudellys Andrade-Silva ◽

Maria Da Conceição Abreu Bandeira ◽

...

Keyword(s):

Community Structure ◽

Species Composition ◽

Significant Influence ◽

Sand Fly ◽

Forest Fragments ◽

Sand Flies ◽

Human Occupation ◽

Short Term

Abstract Variation in the structure of phlebotomine (sand fly) communities in forest fragments with different degrees of preservation and human occupation (peridomicile) in eastern Amazonia was studied. We identified 43 species of sand flies in our study, of which 38 occurred in both preserved forest areas and in the peridomiciles of short-term settlements, while another 28 species occurred in altered forest fragments and long-term settlements. The composition of the community at each site changed with the type of environment (forest or peridomicile), with the species Lutzomyia evandroi, L. whitmani, L. choti, L. serrana, L. triacantha, L. migonei, L. hirsuta, L. shannoni, and L. brachyphylla accounting for more than 54% of the differences among environments. The quality of the environment exerted a significant influence on the structure of phlebotomine communities, and affected their species composition, richness, and abundance.

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Bryophytes in fragments of Terra Firme forest on the great curve of the Xingu River, Pará state, Brazil 1 Part of Master's Dissertation of the first author.

Brazilian Journal of Biology ◽

10.1590/1519-6984.02814bm ◽

2015 ◽

Vol 75 (3 suppl 1) ◽

pp. 238-249 ◽

Cited By ~ 6

Author(s):

ACC. Pantoja ◽

AL. Ilkiu-Borges ◽

ACC. Tavares-Martins ◽

ET. Garcia

Keyword(s):

Species Composition ◽

Tropical Forest ◽

Environmental Changes ◽

Forest Fragments ◽

Habitat Conditions ◽

Terra Firme ◽

Xingu River ◽

Microclimatic Conditions ◽

Terra Firme Forest ◽

Made In

Abstract Microclimatic conditions of tropical forest favour the high richness of bryophytes, which by being sensitive to environmental changes, are important indicators of habitat conditions. The aim of this study was to determine the richness and species composition of the bryophyte flora in fragments of terra firme forest on the great curve of the Xingu River, Pará state, Brazil. The collections were made in August and September 2012 in 14 fragments, in which were installed two plots per fragment, one at the edge and one inside, measuring 10 × 10 m each. The results showed 77 species in 45 genera and 18 families. Lejeunea setiloba Spruce and Marchesinia brachiata (Sw.) Schiffn. are new records for Pará state. The richness families in this study were the ones typically found in tropical forest surveys. A high richness of rare species in comparison to common ones, a pattern usually observed for plants in tropical forests was not reported in this study, probably due to historical fragmentation and disturbance in the area. The richness and species composition were determined mainly by the physiognomic characteristics of the studied forest fragments.

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Structure and tree species composition of forest fringe of a forest fragment in an oil palm plantation at Suai, Sarawak, Malaysian Borneo

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d220755 ◽

2021 ◽

Vol 22 (7) ◽

Author(s):

Claudia Lennya Jana ◽

ISMAIL JUSOH

Keyword(s):

Species Composition ◽

Oil Palm ◽

Tree Species ◽

Forest Fragments ◽

Forest Fragment ◽

Tree Species Composition ◽

Oil Palm Plantation ◽

Strong Winds ◽

Fragmented Forests ◽

Forest Fringe

Abstract. Jana CL, Jusoh I. 2021. Structure and Tree Species Composition of Forest Fringe of A Forest Fragment in an Oil Palm Plantation at Suai, Sarawak, Malaysian Borne. Biodiversitas 22: 3013-3019. Forest fragments in oil palm plantations are remnants of the original forest tract with various sizes and shapes after clearing forested lands for crops and roads. Fragmented forests usually created forest fringe or edge habitats that differ in light intensity, temperature, humidity, heavy rainfall, and strong winds from its core. The study was aimed to determine the structure and tree species composition of the forest fringe of a fragmented forest in an oil palm plantation Suai, Sarawak. This study established a total of 24 sampling plots within the forest fringe. Tree enumeration and species identification were conducted in all sampling plots to all trees with a diameter at breast height 5 cm and higher. A total of 59 families comprised of 274 species and 948 trees individuals were recorded. The aboveground biomass stand at 260 Mg ha?¹. Species Elateriospermum tapos was predominant, and family Dipterocarpaceace dominated the forest fringe. Based on the calculated indices, species diversity and richness were considered high, while the dispersion of individual trees was random but unevenly distributed. Natural regeneration in the forest fringe is sustainable. The forest structure and species composition are intact, and without significant disturbance, the whole forest fragment is self-sustain.

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