scholarly journals Effects of deforestation pattern and private nature reserves on the forest conservation in settlement areas of the Brazilian Amazon

2001 ◽  
Vol 1 (1-2) ◽  
pp. 1-14 ◽  
Author(s):  
Jean Paul Metzger

The effects of deforestation patterns, private nature-reserve extents and agricultural fallow periods on forest conservation were simulated for settlement projects in the Brazilian Amazon that produce a fish-bone pattern of occupation and where slash-and-burn agriculture is predominantly used. Data for simulation was obtained from previous work at the Bragantina region, the oldest agricultural frontier in the Brazilian Amazon. Forest conservation was evaluated using the size of remnant forest fragments, the amount of interior habitat, the connectivity among fragments and the extent of fragmentation. Results showed that the best scenario for forest conservation is the maintenance of 80% of the lot as privatereserve using deforestation pattern that allow to group the reserves from different farmers at the end of the lot. When private-reserve coverage is bellow 80% of the landscape, forest conservation status will be influenced by the deforestation pattern. Some patterns (e.g. random location of deforestation plots) will then be particularly deleterious, producing a highly fragmented landscape, while other patterns (e.g., progressive deforestation from one edge) can allow the maintenance of large forest fragments. To get forest conservation in these cases, private-reserve extent and deforestation pattern should be considered together. Considering both forest conservation and agricultural use, progressive patterns of deforestation (or land use) in a lot of 2,000m by 500m, with private nature-reserves covering 50% of the landscape seems to be the best compromise. To guarantee the private forest preservation, these forests should be pre-established when settlements are planned and grouped at the end of the lots.

2021 ◽  
Vol 46 (2) ◽  
pp. 273-279
Author(s):  
Aline Fernandes Pontes-Pires ◽  
Maria Regina de V. Barbosa ◽  
David M. Johnson

Abstract— During a taxonomic and phylogenetic study of Xylopia from the Amazon River basin, South America, we examined collections from the Brazilian states of Amazonas, Mato Grosso, Pará, Rondônia, and Tocantins that resembled Xylopia nitida by some characteristics of the leaves, but differed consistently from the latter in a number of floral and fruit characters. On the basis of these specimens we describe here a new species, Xylopia maasiana. The new species is a small to medium-sized tree encountered mostly in riparian habitats across the southern Brazilian Amazon and in some transition areas between the Amazon forest and cerrado biomes in Central Brazil. In addition to the detailed description, we include a preliminary assessment of conservation status, taxonomic comments, illustrations, a distribution map of the new species, and comparison with X. nitida.


Rodriguésia ◽  
2021 ◽  
Vol 72 ◽  
Author(s):  
Paulo Henrique Gaem ◽  
Eve Lucas ◽  
Ana Andrade ◽  
Alberto Vicentini ◽  
Fiorella Fernanda Mazine

Abstract Myrcia is the sole genus of the Myrciinae, one of the nine subtribes of Myrteae (Myrtaceae). The Amazon forest holds about one-quarter of the Brazilian species of Myrcia, but the genus is still understudied in this whole region. In this context, this study presents a floristic survey of Myrcia in the permanent plots of the Biological Dynamics of Forest Fragments Project (BDFFP), in Amazonas state, Brazil. The genus is represented by 36 species in the study area, comprehending 32% of its total richness in the Brazilian Amazon forest, with 19 of them endemic to this domain. Myrcia neospeciosa is reported as a new occurrence for Amazonas state and M. grandis is recorded for the first time from upland terra firme forests on clayish soils. Myrcia cuspidata, a species with calyptrate flowers, is classified under Myrcia sect. Aulomyrcia, representing the second taxon of the genus with this feature removed from Myrcia sect. Calyptranthes. Finally, morphological aspects of the infra-generic categories of Myrcia are reported more overlapping than previously thought. A map containing the location of the study area, an identification key, descriptions, comments, and figures are provided.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
R. Libonati ◽  
J. M. C. Pereira ◽  
C. C. Da Camara ◽  
L. F. Peres ◽  
D. Oom ◽  
...  

AbstractBiomass burning in the Brazilian Amazon is modulated by climate factors, such as droughts, and by human factors, such as deforestation, and land management activities. The increase in forest fires during drought years has led to the hypothesis that fire activity decoupled from deforestation during the twenty-first century. However, assessment of the hypothesis relied on an incorrect active fire dataset, which led to an underestimation of the decreasing trend in fire activity and to an inflated rank for year 2015 in terms of active fire counts. The recent correction of that database warrants a reassessment of the relationships between deforestation and fire. Contrasting with earlier findings, we show that the exacerbating effect of drought on fire season severity did not increase from 2003 to 2015 and that the record-breaking dry conditions of 2015 had the least impact on fire season of all twenty-first century severe droughts. Overall, our results for the same period used in the study that originated the fire-deforestation decoupling hypothesis (2003–2015) show that decoupling was clearly weaker than initially proposed. Extension of the study period up to 2019, and novel analysis of trends in fire types and fire intensity strengthened this conclusion. Therefore, the role of deforestation as a driver of fire activity in the region should not be underestimated and must be taken into account when implementing measures to protect the Amazon forest.


Phytotaxa ◽  
2021 ◽  
Vol 510 (2) ◽  
Author(s):  
KAUÊ NICOLAS LINDOSO DIAS ◽  
FABRÍCIO MOREIRA FERREIRA ◽  
PEDRO LAGE VIANA

Pariana caxiuanensis (Poaceae) is described and illustrated as a new species from the Brazilian Amazon. The new species is characterized by having the leaves clustered at the apex of the leafy culm, fimbriae few to absent, dimorphic flowering culms, large ligules (2.5–4 mm long), and pubescent to hirsute synflorescences. We present a morphological description, illustrations of the new species, the conservation status assessment, and a key to differentiate P. caxiuanensis from its morphologically related congeners.


2011 ◽  
Vol 64 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Marcondes Lima da Costa ◽  
Gaspar Morcote Rios ◽  
Mônia Maria Carvalho da Silva ◽  
Glayce Jholy da Silva ◽  
Uliana Molano-Valdes

Several Archaeological Dark Earth (ADE) sites have been already found in the Colombian Amazon forest showing high content of archaeological ceramic fragments similarly to those in the Brazilian Amazon represented by Quebrada Tacana site. Their fragments are yellow to grey colour, display a burned clayey matrix which involves fragments of cariapé and coal and ash particles, besides grains of quartz and micas. The clay matrix is made of metakaolinite, quartz, and some mica flakes, chlorite and sepiolite. Cariapé and cauixi spicules are constituted of cristobalite, which is also the main mineral component of the coal and ashes. Although not detected by X-ray diffraction, the phosphate minerals should be present, since the contents of phosphor reach up to 2.90 Wt.% P2O5. Possibly it occurs as aluminium-phosphate, since Ca contents fall below 0.1 Wt.%. These mineralogical and chemical characteristics allow to correlate these ceramic fragments with those found in the ADE in Brazil and reinforce phosphor as an important chemical component, which indicates human activity by the daily use of pottery all over the Amazon region.


2019 ◽  
Vol 50 (2) ◽  
pp. 219-227 ◽  
Author(s):  
Felipe de Figueiredo Silva ◽  
Richard K. Perrin ◽  
Lilyan E. Fulginiti

Hoehnea ◽  
2016 ◽  
Vol 43 (1) ◽  
pp. 119-134 ◽  
Author(s):  
Aline Melo ◽  
Elsie F. Guimarães ◽  
Marccus Alves

ABSTRACT Peperomia is the second most diverse genus of Piperaceae, with an estimated 1,600 species and a pantropical distribution. This work aims to present a taxonomic synopsis of the genus in the State of Roraima, in the extreme north of the Brazilian Amazon forest and belonging to the central-south portion of the Guayana Shield. Based on collecting expeditions and analysis of specimens in various herbaria, 23 taxa were recognized, with two new records for the State and one of them, a new record for Brazil. The taxa are differentiated mainly by phyllotaxis, shape and size of their leaves, in addition to habit and fruits. They have been found in areas of lowland, submontane, montane, tepui and floodplain (várzea) forests and mostly show a distribution restricted to the Neotropics. Some species in the state are presently known exclusively from Mount Roraima, and restricted to a few specimens.


Biotropica ◽  
2015 ◽  
Vol 48 (2) ◽  
pp. 170-180 ◽  
Author(s):  
Juliana M. Silveira ◽  
Julio Louzada ◽  
Jos Barlow ◽  
Rafael Andrade ◽  
Luiz Mestre ◽  
...  

2019 ◽  
Vol 12 (2) ◽  

Cavite’s remaining upland forest fragments are either remnant from commercial logging activities ca. 25-45 years ago or as a direct result of land conversions for agriculture or human settlements. These forest fragments are very significant because they represent areas where pockets of wildlife habitat still remain. The terrestrial vertebrates are often used to assess animal diversity because they are ideal biological indicators of environmental change and anthropogenic disturbances. The study aimed to determine terrestrial vertebrate diversity, conservation status, and identify major anthropogenic threats in these fragments. Terrestrial vertebrates were surveyed using a combination of strip-transect sampling, time-constrained searches, visual encounter survey (VES), and acoustic encounter survey (AES; for amphibians only), point counts, live trapping and mist netting from October 2014 to March 2016. Species richness and biodiversity estimation were computed using Shannon-Wiener Diversity Index, linear regression, detection and probability modeling using PAST, and confidence limits for nestedness (0.05α) using EpiTools. A total of 175 terrestrial vertebrates were documented and among the vertebrate groups, the birds had the highest observed diversity. Twenty-nine (19 birds, 3 mammals, 3 lizards, and 4 anurans) species are listed as threatened. Habitat loss and degradation due to the conversion of habitats to agricultural and/or residential areas remained to be the most prevalent threat in the remaining forested areas in upland Cavite. Baseline data generated shall be used in the different government biodiversity monitoring activities as the basis for impacts and mitigation and initial planning for the management and conservation of these remaining forest patches.


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