Distance from roads and cities as a predictor of habitat loss and fragmentation in the caatinga vegetation of Brazil

Roads and cities represent huge sources of degradation for adjacent ecosystems regarding nutrient cycling, energy, water flow and species composition. In this study we test the hypothesis that distance from roads and cities is associated with habitat loss and fragmentation in the caatinga vegetation- a dry forest to scrub vegetation that covers ca. 736,000 km² of northeast Brazil. The study site comprised a 2,828.8 km² piece (64 km x 44.2 km) of Xingó region (09°36'S, 37°50'W), which is located between the States of Alagoas and Sergipe. Based on satellite imagery we mapped the remaining vegetation, 145 km of paved roads and the seven small-sized cities set in the study site. A positive correlation was found between the combined distance from roads and cities and the percentage of remaining vegetation as it dropped from 18% at 12 km distant to 5.9% at 1 km distant from cities and roads. Thus, remaining vegetation was reduced by one third near cities and roads. A positive correlation was also found between distance from cities and roads and the percentage of fragments larger than 200 ha, which ranged from 3.6% (within 3 km distance class) to 23.3% (15 km distance class) of all fragments. Our results suggest a road/city-effect zone of 12 to 15 km width, over which habitat loss and fragmentation extend throughout the caatinga vegetation. These findings should be considered in the regional polices for biodiversity conservation and economic development of the caatinga region.

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Multi-taxa ecological responses to habitat loss and fragmentation in western Amazonia as revealed by RAPELD biodiversity surveys

Acta Amazonica ◽

10.1590/1809-4392202004532 ◽

2021 ◽

Vol 51 (3) ◽

pp. 234-243

Author(s):

Gabriel M. MOULATLET ◽

Emmanuel AMBRIZ ◽

Jennifer GUEVARA ◽

Karima G. LÓPEZ ◽

Marina RODES-BLANCO ◽

...

Keyword(s):

Species Composition ◽

Habitat Loss ◽

Forest Cover ◽

Landscape Fragmentation ◽

Dung Beetles ◽

Landscape Configuration ◽

Edge Density ◽

Logistic Regression Models ◽

Habitat Loss And Fragmentation ◽

Taxonomic Groups

ABSTRACT Habitat loss and fragmentation caused by deforestation are important anthropogenic drivers of changes in biodiversity in the Amazon rainforest, and has reached its highest rate in recent decades. However, the magnitude and direction of the effects on species composition and distribution have yet to be fully understood. We evaluated the responses of four taxonomic groups − birds, amphibians, orchid bees, and dung beetles - to habitat loss and fragmentation at both species and assemblage level in the northern Ecuadorian Amazon. We sampled fifteen 250-m long plots in terra-firme forest remnants. We calculated one landscape fragmentation index (fragindex), which considers the proportion of continuous forest cover, edge density and isolation in the landscape, and nine landscape configuration metrics. Logistic regression models and multivariate regression trees were used to analyze species and assemblage responses. Our results revealed that over 80% of birds, amphibians or orchid-bee species, and 60% of dung beetles were negatively affected by habitat loss and fragmentation. Species composition of all taxonomic groups was significantly affected by differences in forest cover and connectivity. Less than 5% of all species were restricted to landscapes with fragindex values higher than 40%. Landscape metrics related to the shape and area of forest patches determined the magnitude and direction of the effect on species responses. Therefore, changes in the landscape configuration of Ecuadorian Amazonia should be minimized to diminish the effects of habitat loss and fragmentation on species occurrence and assemblage composition.

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Effect of habitat loss and fragmentation on fruit-feeding butterflies in the Brazilian Atlantic Forest

Canadian Journal of Zoology ◽

10.1139/cjz-2018-0202 ◽

2019 ◽

Vol 97 (7) ◽

pp. 588-596 ◽

Cited By ~ 1

Author(s):

D.H.A. Melo ◽

B.K.C. Filgueiras ◽

C.A. Iserhard ◽

L. Iannuzzi ◽

A.V.L. Freitas ◽

...

Keyword(s):

Species Composition ◽

Atlantic Forest ◽

Habitat Loss ◽

Habitat Type ◽

Forest Edge ◽

Fragmented Landscape ◽

Brazilian Atlantic Forest ◽

Habitat Loss And Fragmentation ◽

Threatened Taxa ◽

Butterfly Assemblages

Habitat loss and fragmentation have drastically altered the availability and quality of tropical forest habitats, but information on how such changes influence local biodiversity is still insufficient. Here, we examine the effects of both patch and landscape metrics on fruit-feeding butterfly assemblages in a fragmented landscape of the Brazilian Atlantic Forest. Our study was carried out in three habitat types: eight fragments (ranging from 8 to 126 ha), eight areas of forest edge (50 m from forest border), and eight areas of forest interior (>200 m from forest border) of the largest remnant (3500 ha) of the Atlantic Forest of northeast Brazil. Our results demonstrated that fragment area is negatively correlated with observed and estimated richness and abundance of butterflies, whereas habitat type is correlated with estimated richness and abundance of butterflies. Species composition responded to habitat type, fragment area, and distance between sample units. These findings illustrated (i) fruit-feeding butterfly sensitivity to habitat loss and fragmentation, (ii) that species composition and abundance are adequate parameters to access the responses of fruit-feeding butterflies to habitat loss and fragmentation, and (iii) the relevance of a heterogeneous and connected landscape for conservation of butterflies, where small fragments are important for generalist or open-habitat specialists and large remnants are key for disturbance-sensitive and threatened taxa.

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Potential extinction debt due to habitat loss and fragmentation in subalpine moorland ecosystems

Plant Ecology ◽

10.1007/s11258-021-01118-4 ◽

2021 ◽

Author(s):

Daichi Makishima ◽

Rui Sutou ◽

Akihito Goto ◽

Yutaka Kawai ◽

Naohiro Ishii ◽

...

Keyword(s):

Habitat Loss ◽

Extinction Debt ◽

Habitat Loss And Fragmentation

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Consequences of habitat loss and fragmentation for wetland amphibian assemblages

Wetlands ◽

10.1007/bf03161728 ◽

1999 ◽

Vol 19 (1) ◽

pp. 1-12 ◽

Cited By ~ 169

Author(s):

Richard M. Lehtinen ◽

Susan M. Galatowitsch ◽

John R. Tester

Keyword(s):

Habitat Loss ◽

Habitat Loss And Fragmentation

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Assessing Mammal Species Losses Due to Habitat Loss and Fragmentation Across the World's Terrestrial Ecoregions

SSRN Electronic Journal ◽

10.2139/ssrn.3796529 ◽

2021 ◽

Author(s):

Koen Jacobus Josefus Kuipers ◽

Jelle P. Hilbers ◽

John Garcia-Ulloa ◽

Bente J. Graae ◽

Roel May ◽

...

Keyword(s):

Habitat Loss ◽

Mammal Species ◽

Habitat Loss And Fragmentation

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Squamata reptiles of a fragment of tropical dry forest in northwestern Venezuela (Lake Maracaibo region)

Check List ◽

10.15560/8.6.1220 ◽

2012 ◽

Vol 8 (6) ◽

pp. 1220 ◽

Cited By ~ 1

Author(s):

Junior T. Larreal ◽

Gilson A. Rivas ◽

Carlos Portillo-Quintero ◽

Tito R. Barros

Keyword(s):

Species Composition ◽

San Francisco ◽

Tropical Dry Forest ◽

Single Species ◽

Dry Forest ◽

Forest Fragment ◽

Dry Forests ◽

Maracaibo Basin ◽

Lake Maracaibo

We present a commented taxonomic list of the reptiles found during herpetological surveys carried out in an isolated fragment of tropical dry forest located in the municipality of San Francisco, Zulia state, northwestern Venezuela between January-December 2011. We report a total of 24 species belonging to the order Squamata, distributed in 12 families and 21 genera. Colubridae is the most diverse family with six species, followed by Dipsadidae (four species), Boidae, Gymnophthalmidae, Phyllodactylidae and Teiidae with two species each, and finally Dactyloidae, Iguanidae, Elapidae, Gekkonidae, Sphaerodactylidae and Viperidae with a single species each. The species composition at this site matches what would be expected in a tropical dry forest in the region. Our study suggests that this isolated tropical dry forest fragment is the last refuge of the herpetofauna that once occupied much of the dry forests of the northern Maracaibo basin and should therefore be considered for conservation purposes.

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Peacekeeping, Compliance with International Norms, and Transactional Sex in Monrovia, Liberia

International Organization ◽

10.1017/s0020818316000242 ◽

2016 ◽

Vol 71 (1) ◽

pp. 1-30 ◽

Cited By ~ 27

Author(s):

Bernd Beber ◽

Michael J. Gilligan ◽

Jenny Guardado ◽

Sabrina Karim

Keyword(s):

Economic Development ◽

United Nations ◽

Gender Equality ◽

Satellite Imagery ◽

International Norms ◽

Transactional Sex ◽

Large Majority ◽

Sensitive Questions ◽

Development Goals ◽

Sexual Histories

AbstractUnited Nations policy forbids its peacekeepers and other personnel from engaging in transactional sex (the exchange of money, favors, or gifts for sex), but we find the behavior to be very common in our survey of Liberian women. Using satellite imagery and GPS locators, we randomly selected 1,381 households and randomly sampled 475 women between the ages of eighteen and thirty. Using an iPod in private to preserve the anonymity of their responses, these women answered sensitive questions about their sexual histories. More than half of them had engaged in transactional sex, a large majority of them (more than 75 percent) with UN personnel. We estimate that each additional battalion of UN peacekeepers caused a significant increase in a woman's probability of engaging in her first transactional sex. Our findings raise the concern that the private actions of UN personnel in the field may set back the UN's broader gender-equality and economic development goals, and raise broader questions about compliance with international norms.

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