Ten-Year Landsat Classification of Deforestation and Forest Degradation in the Brazilian Amazon

Fires are both a cause and consequence of important changes in the Amazon region. The development and implementation of better fire management practices and firefighting strategies are important steps to reduce the Amazon ecosystems’ degradation and carbon emissions from land-use change in the region. We extended the application of the maximum entropy method (MaxEnt) to model fire occurrence probability in the Brazilian Amazon on a monthly basis during the 2008 and 2010 fire seasons using fire detection data derived from satellite images. Predictor variables included climatic variables, inhabited and uninhabited protected areas and land-use change maps. Model fit was assessed using the area under the curve (AUC) value (threshold-independent analysis), binomial tests and model sensitivity and specificity (threshold-dependent analysis). Both threshold-independent (AUC = 0.919 ± 0.004) and threshold-dependent evaluation indicate satisfactory model performance. Pasture, annual deforestation and secondary vegetation are the most effective variables for predicting the distribution of the occurrence data. Our results show that MaxEnt may become an important tool to guide on-the-ground decisions on fire prevention actions and firefighting planning more effectively and thus to minimise forest degradation and carbon loss from forest fires in Amazonian ecosystems.

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Quantifying forest loss and forest degradation in Myanmar’s “home of teak”

Canadian Journal of Forest Research ◽

10.1139/cjfr-2018-0508 ◽

2020 ◽

Vol 50 (2) ◽

pp. 89-101

Author(s):

Thu Ya Kyaw ◽

René H. Germain ◽

Stephen V. Stehman ◽

Lindi J. Quackenbush

Keyword(s):

Supervised Classification ◽

Landsat Imagery ◽

Reference Sample ◽

Tectona Grandis ◽

Forest Degradation ◽

Training Data ◽

Forest Loss ◽

Mountain Range ◽

And Training

The Bago Mountain Range in Myanmar is known as the “home of teak” (Tectona grandis L. f.) because of its bountiful, naturally growing teak-bearing forests. Accelerating forest loss and degradation are threatening the sustainable production of teak in the region. Changes in land cover between 2000 and 2017 in four reserved forests of the Bago Mountain Range were mapped using supervised classification of Landsat imagery and training data collected in the field. A stratified random sample was used to collect reference data to assess accuracy of the maps and estimate area. Based on the reference sample, it was estimated that the forest area declined from 71 240 ha (standard error (SE) = 1524 ha) in 2000 to 40 891 ha (SE = 4404 ha) in 2017, whereas the area of degraded forests increased from 88 797 ha (SE = 1694 ha) to 97 013 ha (SE = 5395 ha). The annualized rates of gross forest loss and gross forest degradation were 1.03% and 0.97%, respectively, indicating that forest degradation paralleled forest loss. In many degraded areas, there is an opportunity to ameliorate the situation through silviculture. The 2017 map identifies bamboo-dominated degraded forests where enrichment planting or reforestation is recommended.

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A new species and taxonomic notes on Lycianthes series Glanduliferae (Solanaceae) from the Brazilian Amazon

Phytotaxa ◽

10.11646/phytotaxa.527.1.5 ◽

2021 ◽

Vol 527 (1) ◽

pp. 51-59

Author(s):

RAFAEL COSTA-SILVA ◽

LEANDRO LACERDA GIACOMIN ◽

MARIA DE FATIMA AGRA

Keyword(s):

Electron Microscopy ◽

New Species ◽

Conservation Status ◽

Glandular Trichomes ◽

Brazilian Amazon ◽

Terra Firme ◽

Brazilian Flora ◽

A New Species ◽

Scanning Electron

During our analyses of Lycianthes exsiccates, as part of the taxonomic treatment for the Brazilian flora, a new species was discovered and is described and illustrated here. The species is compared and contextualized within the infra-generic classification of Lycianthes. Analyses of indument and trichomes were performed by stereomicroscopy (SM) and scanning electron microscopy (SEM). The new species, Lycianthes amazonica, is recognized as an endemic species to the Brazilian Amazon, which has its habitat described as secondary formations (capoeira) of terra-firme forests. It is closely related to L. sprucei, with which shares the scandent or vine habit, flexuous branches and ferrugineous indument of glandular trichomes. However, they are distinguished by several morphological features, including trichomes morphology, a sessile inflorescence and calyx appendages of equal length; both species belong to Lycianthes. subg. Polymeris sect. Eulycianthes ser. Glanduliferae. The description of this species expands the total number of Lycianthes species to the Brazilian Amazon to six, as well as thirteen to Brazil. The affinities of Lycianthes amazonica with its related species, distribution, ecology, and conservation status are discussed. Additionally, a lectotypification of Lycianthes sprucei, a species closely related to L. amazonica, is proposed.

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Rapid Recent Deforestation Incursion in a Vulnerable Indigenous Land in the Brazilian Amazon and Fire-Driven Emissions of Fine Particulate Aerosol Pollutants

Forests ◽

10.3390/f11080829 ◽

2020 ◽

Vol 11 (8) ◽

pp. 829

Author(s):

Gabriel de Oliveira ◽

Jing M. Chen ◽

Guilherme A. V. Mataveli ◽

Michel E. D. Chaves ◽

Hugo T. Seixas ◽

...

Keyword(s):

Respiratory Health ◽

Human Health Risk ◽

Agricultural Practices ◽

Brazilian Amazon ◽

Forest Degradation ◽

Climate Feedback ◽

Emission Model ◽

Annual Average ◽

Fire Emissions ◽

Indigenous Land

Deforestation in the Brazilian Amazon is related to the use of fire to remove natural vegetation and install crop cultures or pastures. In this study, we evaluated the relation between deforestation, land-use and land-cover (LULC) drivers and fire emissions in the Apyterewa Indigenous Land, Eastern Brazilian Amazon. In addition to the official Brazilian deforestation data, we used a geographic object-based image analysis (GEOBIA) approach to perform the LULC mapping in the Apyterewa Indigenous Land, and the Brazilian biomass burning emission model with fire radiative power (3BEM_FRP) to estimate emitted particulate matter with a diameter less than 2.5 µm (PM2.5), a primary human health risk. The GEOBIA approach showed a remarkable advancement of deforestation, agreeing with the official deforestation data, and, consequently, the conversion of primary forests to agriculture within the Apyterewa Indigenous Land in the past three years (200 km2), which is clearly associated with an increase in the PM2.5 emissions from fire. Between 2004 and 2016 the annual average emission of PM2.5 was estimated to be 3594 ton year−1, while the most recent interval of 2017–2019 had an average of 6258 ton year−1. This represented an increase of 58% in the annual average of PM2.5 associated with fires for the study period, contributing to respiratory health risks and the air quality crisis in Brazil in late 2019. These results expose an ongoing critical situation of intensifying forest degradation and potential forest collapse, including those due to a savannization forest-climate feedback, within “protected areas” in the Brazilian Amazon. To reverse this scenario, the implementation of sustainable agricultural practices and development of conservation policies to promote forest regrowth in degraded preserves are essential.

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Classification of successional forest stages in the Brazilian Amazon basin

Forest Ecology and Management ◽

10.1016/s0378-1127(03)00003-3 ◽

2003 ◽

Vol 181 (3) ◽

pp. 301-312 ◽

Cited By ~ 56

Author(s):

Dengsheng Lu ◽

Paul Mausel ◽

Eduardo Brondı́zio ◽

Emilio Moran

Keyword(s):

Amazon Basin ◽

Brazilian Amazon

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Fire Occurrences and Greenhouse Gas Emissions from Deforestation in the Brazilian Amazon

Remote Sensing ◽

10.3390/rs13030376 ◽

2021 ◽

Vol 13 (3) ◽

pp. 376

Author(s):

Claudia Arantes Silva ◽

Giancarlo Santilli ◽

Edson Eyji Sano ◽

Giovanni Laneve

Keyword(s):

Greenhouse Gas ◽

Ghg Emissions ◽

Brazilian Amazon ◽

Forest Degradation ◽

Primary Forest ◽

Steady Increase ◽

Strong Impact ◽

Ecosystem Degradation ◽

Slash And Burn ◽

Forest Clearing

This work presents the dynamics of fire occurrences, greenhouse gas (GHG) emissions, forest clearing, and degradation in the Brazilian Amazon during the period 2006–2019, which includes the approval of the new Brazilian Forest Code in 2012. The study was carried out in the Brazilian Amazon, Pará State, and the municipality of Novo Progresso (Pará State). The analysis was based on deforestation and fire hotspot datasets issued by the Brazilian Institute for Space Research (INPE), which is produced based on optical and thermal sensors onboard different satellites. Deforestation data was also used to assess GHG emissions from the slash-and-burn practices. The work showed a good correlation between the occurrence of fires in the newly deforested area in the municipality of Novo Progresso and the slash-and-burn practices. The same trend was observed in the Pará State, suggesting a common practice along the deforestation arch. The study indicated positive coefficients of determination of 0.72 and 0.66 between deforestation and fire occurrences for the municipality of Novo Progresso and Pará State, respectively. The increased number of fire occurrences in the primary forest suggests possible ecosystem degradation. Deforestation reported for 2019 surpassed 10,000 km2, which is 48% higher than the previous ten years, with an average of 6760 km2. The steady increase of deforestation in the Brazilian Amazon after 2012 has been a worldwide concern because of the forest loss itself as well as the massive GHG emitted in the Brazilian Amazon. We estimated 295 million tons of net CO2, which is equivalent to 16.4% of the combined emissions of CO2 and CH4 emitted by Brazil in 2019. The correlation of deforestation and fire occurrences reported from satellite images confirmed the slash-and-burn practice and the secondary effect of deforestation, i.e., degradation of primary forest surrounding the deforested areas. Hotspots’ location was deemed to be an important tool to verify forest degradation. The incidence of hotspots in forest area is from 5% to 20% of newly slashed-and-burned areas, which confirms the strong impact of deforestation on ecosystem degradation due to fire occurrences over the Brazilian Amazon.

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