Tropical deforestation Research Papers - Academia.edu (original) (raw)
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- Landscape Ecology, Brazil, Amazonia, Ecohydrology
Tropical deforestation remains a critical issue given its present rate and a widespread consensus regarding its implications for the global carbon cycle and biodiversity. Nowhere is the problem more pronounced than in the Amazon basin,... more
Tropical deforestation remains a critical issue given its present rate and a widespread consensus regarding its implications for the global carbon cycle and biodiversity. Nowhere is the problem more pronounced than in the Amazon basin, home to the world's largest intact, tropical forest. This article addresses land cover change processes at household level in the Amazon basin, and to this end adapts a concept of domestic life cycle to the current institutional environment of tropical frontiers. In particular, it poses a risk minimization model that integrates demography with market-based factors such as transportation costs and accessibility. In essence, the article merges the theory of Chayanov with the household economy framework, in which markets exist for inputs (including labor), outputs, and capital. The risk model is specified and estimated, using survey data for 261 small producers along the Transamazon Highway in the eastern sector of the Brazilian Amazon.
This paper applies a spatial economic regression model to analyze the relation between deforestation in the period from 1989 to 1994 and access to roads and markets, ecological conditions, land tenure, and zoning policies in Santa Cruz,... more
This paper applies a spatial economic regression model to analyze the relation between deforestation in the period from 1989 to 1994 and access to roads and markets, ecological conditions, land tenure, and zoning policies in Santa Cruz, Bolivia. The data comes from a Geographic Information System (GIS) compiled by the Natural Resources Department of the Santa Cruz Government. Locations closer to roads and the City of Santa Cruz and that have more fertile soils and higher rainfall have a greater probability of being deforested. The same also applies to colonization areas. National parks and areas occupied by indigenous people do not have significantly less deforestation than sites with similar acess and ecological conditions. Forest concessions, on the other hand seem to protect forests.
In September 2021, the Cat Specialist Group completed the Red List Assessment for mainland clouded leopard Neofelis nebulosa (Gray et al. 2021) for the IUCN Red List of Threatened Species TM. Since the previous Red List assessment... more
In September 2021, the Cat Specialist Group completed the Red List Assessment for mainland clouded leopard Neofelis nebulosa (Gray et al. 2021) for the IUCN Red List of Threatened Species TM. Since the previous Red List assessment (Grassman et al. 2016), there have been several published studies investigating the range-wide distribution of remaining habitat and recent occurrence records (e.g., Macdonald et al. 2019, Petersen et al. 2020a). These assisted the most recent assessment, as did new published estimates on site-specific population densities (e.g., Singh & Macdonald 2017, Petersen et al. 2020b, Fig. 1.). This latest assessment resulted in the species maintaining its status as globally Vulnerable.
By their biophysical conditions, tropical forests have a large ability to provide ecosystem services. The Paranaense Forest, one of the most threatened tropical rainforests of South America, has now reached 1,200,000 has., mainly... more
By their biophysical conditions, tropical forests have a large ability to provide
ecosystem services. The Paranaense Forest, one of the most threatened tropical
rainforests of South America, has now reached 1,200,000 has., mainly preserved in
Argentina and to a lesser extent in Brazil and Paraguay. This work aims to analyze
the loss of regulation services from the assessment of the deforestation process and
land use change between 2001 and 2011 in an Argentinean-Brazilian Binational
Basin, the San Antonio River Basin (SArB). The surface of the basin (117,348 has.),
which is part of the Iguazú River, is distributed similarly in both countries. However,
the classification of satellite images (Landsat 5 TM sensor) reveals that, in 2011,
Argentina retains 61.7% of forested areas prevailing regulatory services, while Brazil
25%. Nevertheless, the average annual total deforestation (R) and the annual
change rate (q) in the period were significantly higher in the Argentinean sector (R:
8.143, q: 0.02) than in Brazil (R: 1.493, q: 0.01). The temperature data provided by
the satellite (band 6) indicate a direct relationship between lower temperatures and
the forest area, which coincides with the classification made. It is considered
essential to deepen the analysis of the links between the ability to provision
ecosystem services and social demands, as well as of the development of
methodologies for valuation services in border areas.
Keywords: regulation and supply services, deforestation and annual change rates,
border areas, integrated watershed management.
Understanding the effect of anthropogenic disturbance, and its interaction with carnivores and their prey, is crucial to support the conservation of threatened carnivores, particularly in rapidly changing landscapes. Based on systematic... more
Understanding the effect of anthropogenic disturbance, and its interaction with carnivores and their prey, is crucial to support the conservation of threatened carnivores, particularly in rapidly changing landscapes. Based on systematic camera-trap sampling of four protected areas in Riau Province of central Sumatra, we assessed the habitat occupancy and spatiotemporal overlap between people, potential carnivore prey, and four threatened species of medium-sized or large carnivores: Sumatran tigers (Panthera tigris sumatrae), Malayan sun bears (Helarctos malayanus), dholes (Cuon alpinus), and Sunda clouded leopards (Neofelis diardi). To assess spatial overlap of target species, we used single-species occupancy models and applied a Species Interaction Factor (SIF) to conditional two-species occupancy models. We also used kernel density estimation (KDE) to assess temporal overlap among these species. Our habitat use models showed that altitude (elevation) strongly influenced the occupancy of all large carnivores and potential prey species. Except for Sunda clouded leopards, the occurrence of large carnivore species was positively related to the spatial co-occurrence of humans (SIF > 1). In addition, we found that sun bears and dholes both exhibited high spatial overlap with tigers, and that sun bears alone exhibited high temporal overlap with people. Our findings contribute to an improved understanding of the contemporary ecology of carnivores and their prey in rapidly changing, southeast Asian landscapes. Such knowledge is important to the conservation and recovery of large carnivores in conservation hotspots that are increasingly dominated by humans across Sumatra, as well as globally.
Understanding patterns of tropical deforestation is a crucial issue for Mexico, a country that has lost more than 95% of its original rainforest cover. This paper examines the causes of accelerated deforestation in the Sierra Santa Marta,... more
Understanding patterns of tropical deforestation is a crucial issue for Mexico, a country that has lost more than 95% of its original rainforest cover. This paper examines the causes of accelerated deforestation in the Sierra Santa Marta, Veracruz, Mexico, by looking at settlement history and the evolution of productive schemes in the villages of Venustiano Carranza and Magallanes. Both settlements were founded in the 1960s, after the government donated land to landless peasants. Conversion of forests into pastures, after several agricultural enterprises failed, resulted in more than 80% of the original tropical rainforests being removed in both communities between 1960 and 1998. The process of deforestation in the villages differed from models proposed for the Amazon and Central America, in which deforestation responded to capitalintensive efforts to open up the tropical frontier. In the villages, transformation of forests into pastures was, from the beginning, a smallholder phenomenon. Misguided policies and institutional malfunctions appeared to direct households toward deforestation. Nevertheless, environmental deterioration could not only be explained by external causes. Inside the communities, demographic pressure over land, the modification of traditional land tenure systems and the cultural adoption of cattle as a way to overcome poverty were significant factors in the relationship between colonization and forest clearance. Deforestation at Venustiano Carranza and Magallanes cannot be considered an ecologically destructive practice performed by peasants. In fact, the process reflects not only a lack of environmental awareness in national development policies, but also the intricate interaction of ecological, cultural, social and economical variables.
- by Tom Headland and +1
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- Economics, Socioeconomics, Natural Resources, Conservation
This paper examines how can deforestation affect animal biodiversity in tropical rainforests. It describes what it causes such as the loss of natural habitat, extinction of animals, competition between native species. At the same time, as... more
This paper examines how can deforestation affect animal biodiversity in tropical rainforests. It describes what it causes such as the loss of natural habitat, extinction of animals, competition between native species. At the same time, as a result of this research, some possible solutions are provided to avoid the negative consequences of deforestation.
Tropical forest felling can be for the purpose of traditional shifting cultivation, after which forest is re-established, or for permanent land-use change, which is defined as deforestation. Recent decades have seen a dramatic increase in... more
Tropical forest felling can be for the purpose of traditional shifting cultivation, after which forest is re-established, or for permanent land-use change, which is defined as deforestation. Recent decades have seen a dramatic increase in tropical deforestation caused by slash-and-bum clearing for the establishment of more permanent agriculture, plantations and pastures, which often result in degraded grasslands or degraded fallows. The net CO 2 balance in shifting cultivation is near zero if the forest returns to its original biomass and soil organic carbon status, although there is a small net release of other greenhouse gases during the cropping cycle. Deforestation by contrast normally causes large losses of CO 2 from the soil and vegetation. Greenhouse gas (GHG) emissions are still difficult to quantify. Deforestation may lead to changes in evapotranspiration, runoff and local climate but there are few data. If it occurs in large continuous areas, the rainfall may be decreased, according to modelling studies. There is now no doubt that "human activities are substantially increasing the atmospheric concentrations of the greenhouse gases", and that "these increases will enhance the greenhouse effect" (IPCC, 1990. Climate Change: The IPCC Scientific Assessment). The questions we address in this paper are to what extent slash-and-bum of forest is responsible, and how land conversion of this type will affect the climate system, including its impact on local and regional hydrology.
A recent (2002) analysis concluded that rates of tropical deforestation and atmospheric carbon emissions during the 1990-1997 interval were lower than previously suggested. We challenged this assertion with respect to tropical carbon... more
A recent (2002) analysis concluded that rates of tropical deforestation and atmospheric carbon emissions during the 1990-1997 interval were lower than previously suggested. We challenged this assertion with respect to tropical carbon emissions, but our conclusions were disputed by the authors of the original study. Here we provide further evidence to support our conclusion that the effect of tropical deforestation on greenhousegas emissions and global warming is substantial. At least for Brazilian Amazonia, the net impact of tropical deforestation on global warming may be more than double that estimated in the recent study.
Brazilian Amazonia has particular importance owing to the current rate of forest loss and the vast area of remaining forest at risk of future deforestation. Approximately two-thirds of the Amazon Basin is in Brazil. Brazil’s “Legal... more
Brazilian Amazonia has particular importance owing to the current rate of forest loss and the vast area of remaining forest at risk of future deforestation. Approximately two-thirds of the Amazon Basin is in Brazil. Brazil’s “Legal Amazonia” region refers to a 5 million km2 administrative area covering all or part of nine states; about three-fourths of this area was originally covered by Amazonian forest and one-fourth by cerrado (central-Brazilian savanna) or other non-forest vegetation. The “Amazonia Biome” is the area where the predominant original vegetation was Amazon forest; with the exception of a minuscule area in the state of Maranhão, the Amazonia Biome is entirely contained within Legal Amazonia. When the distinction between these two official Amazon areas is not important, the term “Brazilian Amazonia” is used. Deforestation threatens environmental services in maintaining biodiversity, avoiding greenhouse gas emissions, and recycling water that is essential to maintaining rainfall in Amazonia and in other locations that water vapor is transported to (including São Paulo). Understanding the diverse causes of deforestation in the region is essential to effective efforts to slow and contain the process.
Tropical forests do far more than sustain biodiversity; they are homes to indigenous peoples, pharmacopeias of natural products, and provide vital ecosystem services, such as¯ood amelioration and soil conservation. At regional and global... more
Tropical forests do far more than sustain biodiversity; they are homes to indigenous peoples, pharmacopeias of natural products, and provide vital ecosystem services, such as¯ood amelioration and soil conservation. At regional and global scales, tropical forests also have a major in¯uence on carbon storage and climate. I highlight these bene®ts, then assess the pattern and pace of tropical forest destruction in the Americas, Asia, and Africa. Asia emerges as the most immediate concern, because it has less surviving forest than the other two regions and higher relative rates of deforestation and logging. At regional and national levels, however, there is enormous variation in rates of forest loss. I discuss some factors that tend to promote forest conversion in developing countries, and propose that four Ð human population pressure, weak government institutions and poor policies, increasing trade liberalization, and industrial logging Ð are emerging as key drivers of forest destruction. # 0006-3207/99/$ -see front matter # 1999 Elsevier Science Ltd. All rights reserved. P I I : S 0 0 0 6 -3 2 0 7 ( 9 9 ) 0 0 0 8 8 -9
Brazil’s Amazon deforestation is a major global and national nvironmental concern, and the ability to model and project both its course and the effect of different policy options depends on understanding how this process occurs at... more
Brazil’s Amazon deforestation is a major global and national
nvironmental concern, and the ability to model and project both its course and the effect of different policy options depends on
understanding how this process occurs at present and how it might change in the future. The present paper addresses one key factor in Amazon deforestation: land-tenure concentration in settlements. Brazil’s policies for establishing and regulating settlement projects represent critical government decisions shaping the landscape in the 5 � 106 km2 Legal Amazonia region. We used remote-sensing data and information provided by the National Institute for Colonization and Agrarian Reform (INCRA) to evaluate the effect of land-tenure concentration in a settlement project (Projeto de Assentamento) located in a frontier area where cattle-ranching is expanding. We identified the actors and their
deforestation patterns in the Matupi settlement in the southern part of Brazil’s state of Amazonas. We spatially identified actors who concentrated “lots” (the parcels of land distributed to individual settlers) in 2011 and assessed whether the concentration was done by individual landholders or by “families” (where members merged their lots and the clearing was done together). Deforestation rates (1995–2011) were estimated for each type of actor and the trajectory of deforestation in the settlement (cumulative deforestation to 1994 and annual deforestation 1995–2016) was also analyzed. Concentrators occupied 28% (9653 ha) of the settlement and 29% of the lots (152 lots) analyzed; the numbers of lots concentrated ranged from two to ten. Concentrators of two lots and non-concentrators were the predominant actor types in the settlement. The mean annual clearing per landholding for concentrators of two lots (families: 4.1 � 2.8 ha (mean � SD); individuals: 5.1 � 4.6 ha) was greater than for non-concentrators (1.7 � 1.2 ha), despite their having similar patterns of small clearings.
Concentrators of three or more lots had mean annual clearing per landholding between 6.2 � 12.2 ha and 23.9 � 38.7 ha and, the pattern of patches cleared per year >34 ha in area was predominant. The deforestation rate per lot was higher among concentrators as compared to non-concentrators, showing that lot concentration speeds
deforestation. Analysis of deforestation patterns helps to better understand the process of lot concentration by spatially identifying the predominant patterns of each type of actor. The approach used in our study could assist authorities in identifying and monitoring land-tenure concentration in settlements. Agrarian-reform policymakers
need to monitor this process, since it speeds deforestation in Amazonian settlement projects, as well as undermining the social objectives of the agrarian-reform program.
The following resources related to this article are available online at
This study aims to predict the spatial distribution of tropical deforestation. Landsat images dated 1974Landsat images dated , 1986Landsat images dated and 1991 were classified in order to generate digital deforestation maps which locate... more
This study aims to predict the spatial distribution of tropical deforestation. Landsat images dated 1974Landsat images dated , 1986Landsat images dated and 1991 were classified in order to generate digital deforestation maps which locate deforestation and forest persistence areas. The deforestation maps were overlaid with various spatial variables such as the proximity to roads and to settlements, forest fragmentation, elevation, slope and soil type to determine the relationship between deforestation and these explanatory variables. A multi-layer perceptron was trained in order to estimate the propensity to deforestation as a function of the explanatory variables and was used to develop deforestation risk assessment maps. The comparison of risk assessment map and actual deforestation indicates that the model was able to classify correctly 69% of the grid cells, for two categories: forest persistence versus deforestation. Artificial neural networks approach was found to have a great potential to predict land cover changes because it permits to develop complex, non-linear models.
Efecto de la interacción entre fragmentación y factores ambientales sobre la distribución potencial de psitácidos en la Península de Yucatán TESIS presentada como requisito parcial para optar al grado de Doctor en Ciencias en Ecología y... more
Efecto de la interacción entre fragmentación y factores ambientales sobre la distribución potencial de psitácidos en la Península de Yucatán TESIS presentada como requisito parcial para optar al grado de Doctor en Ciencias en Ecología y Desarrollo Sustentable por Alexis Herminio Plasencia Vázquez 2014 A la memoria de mi padre † que estaría muy orgulloso de tener un doctor en la familia y que presumiría de este título como propio. A mi madre por su apoyo incondicional y por su preocupación desde la distancia.
Tropical deforestation still pervades in the developing countries despite the conservation and development programs implemented by national agencies and international community. Its effects are mostly felt not only by forest dependent... more
Tropical deforestation still pervades in the developing countries despite the conservation and development programs implemented by national agencies and international community. Its effects are mostly felt not only by forest dependent rural communities, but also by other people across the globe in line with the changing climate. In relation to this, up to date and reliable estimates of forest cover is necessary in order to guide the policy makers and forest managers in implementing relevant policies and programs for sustainable forest management and conservation. However, as other tropical countries like the Philippines, forest cover maps and statistics is hampered by multiple imagery sources, varying scale and resolutions, undisclosed methods of mapping and use of different forest classes and definitions. In this study, global and freely available Landsat processed data were used in order to quantify the rates of forest loss on the provincial level and to determine its level of accuracy in the Philippines. The Landsat processed data was enhanced by defining a threshold on percent tree cover that represents forest. However, by applying previously published forest maps, non-forest features were masked out. This data was then analyzed to produce net change ranking and annual forest loss trends and correlations. This was done per forest cover type to provide more detailed insights on forest cover change. Results showed that at least 53,620.20 hectares of forest was lost in the country from year 2000-2012. Overall accuracy indicates high reliability for both loss (86.48%, kappa statistic = 0.86) and gain (92.26%, kappa statistic = 0.92). Mindanao provinces such as Zamboanga Sibugay (-11.30%), Zamboanga del Norte (-5.42%) and Basilan (-4.06) topped the provinces with negative aggregate net changes. Provinces like Surigao del Sur (r = 0.77), Surigao del Norte (r = 0.65) and Ilocos Sur (r = 0.61) had the highest increasing trend of forest loss (p-value at ¡ 0.05). For open forest alone, all Zamboanga provinces showed high aggregate net change while forest cover loss correlations with positive trend were significant in Agusan del Sur (r = 0.70), Tarlac (r = 0.69) and Davao Oriental (r = 0.69). Among the forest cover types analyzed, the open forest (secondary) type exhibited the highest aggregate net change, implying that it was most dynamic and vulnerable to deforestation. This study showed that forest cover changes could be quantified consistently given a globally available platform such as the Landsat processed data.
Deforestation in Brazilian Amazonia destroys environmental services that are important for the whole world, and especially for Brazil itself. These services include maintaining biodiversity, avoiding global warming, and recycling water... more
Deforestation in Brazilian Amazonia destroys environmental services that are important for the whole world, and especially for Brazil itself. These services include maintaining biodiversity, avoiding global warming, and recycling water that provides rainfall to Amazonia, to other parts of Brazil such as São Paulo, and to neighboring countries such as Argentina. The forest also maintains the human populations and cultures that depend on it. Deforestation rates have gone up and down over the years with major economic cycles. A peak of 27,772 km2/year was reached in 2004, followed by a major decline to 4571 km2/year in 2012, after which the rate trended upward, reaching 7989 km2/year in 2016 (equivalent to about 1.5 hectares per minute). Most (70%) of the decline occurred by 2007, and the slowing in this period is almost entirely explained by declining prices of export commodities such as soy and beef. Government repression measures explain the continued decline from 2008 to 2012, but an important part of the effect of the repression program hinges on a fragile base: a 2008 decision that makes the absence of pending fines a prerequisite for credit for agriculture and ranching. This could be reversed at the stroke of a pen, and this is a priority for the powerful “ruralist” voting block in the National Congress. Massive plans for highways, dams and other infrastructure in Amazonia, if carried out, will add to forces in the direction of increased deforestation.
Amazonian biodiversity is increasingly threatened due to the weakening of policies for combating deforestation, especially in Brazil. Loss of animal and plant species, many not yet known to science, is just one among many negative... more
Amazonian biodiversity is increasingly threatened due to the weakening of policies for combating deforestation, especially in Brazil. Loss of animal and plant species, many not yet known to science, is just one among many negative consequences of Amazon deforestation. Deforestation affects indigenous communities, riverside as well as urban populations, and even planetary health. Amazonia has a prominent role in regulating the Earth's climate, with forest loss contributing to rising regional and global temperatures and intensification of extreme weather events. These climatic conditions are important drivers of emerging infectious diseases, and activities associated with deforestation contribute to the spread of disease vectors. This review presents the main impacts of Amazon deforestation on infectious-disease dynamics and public health from a One Health perspective. Because Brazil holds the largest area of Amazon rainforest, emphasis is given to the Brazilian scenario. Finally, potential solutions to mitigate deforestation and emerging infectious diseases are presented from the perspectives of researchers in different fields.
Indonesia's transmigration program to transport people from Java and other densely populated islands to largely forested outer islands has high environmental, social, and financial costs, while doing little towards relieving population... more
Indonesia's transmigration program to transport people from Java and other densely populated islands to largely forested outer islands has high environmental, social, and financial costs, while doing little towards relieving population pressure on Java. Transmigration has been an important cause of forest loss in Indonesia. World Bank fi-nancing promoted the program directly over the [1976][1977][1978][1979][1980][1981][1982][1983][1984][1985][1986][1987][1988][1989] period and continues to underwrite other settlement models that have supplanted earlier programs. The bank projects included creating and strengthening a Ministry of Transmigration, which also carried out settlements of types other than those financed as discrete components of bank loans. Some of these indirectly supported activities have had particularly serious human rights consequences. The case of transmigration provides valuable lessons for tropical countries and international development agencies such as the World Bank, and many of these lessons have yet to be learned.
ABSTRACT The Mt Elgon ecosystem straddles the frontier between Kenya and Uganda and a major catchment for Lake Victoria, the Nile River system and Lake Turkana. It supplies a range of ecosystem goods and services to over 2 million people... more
ABSTRACT The Mt Elgon ecosystem straddles the frontier between Kenya and Uganda and a major catchment for Lake Victoria, the Nile River system and Lake Turkana. It supplies a range of ecosystem goods and services to over 2 million people in Kenya and Uganda. Most of the people are poor, and place tremendous pressure on the integrity of the ecosystem. This has seen conflicts arising from competition for dwindling natural resources in fast degrading landscape.
The forestry industry provides a good illustration of the active roles that industry associations, environmental nongovernmental organizations (NGOs), national governments, and international organizations can play in developing and... more
The forestry industry provides a good illustration of the active roles that industry associations, environmental nongovernmental organizations (NGOs), national governments, and international organizations can play in developing and promoting codes of conduct that are formally sanctioned and certified. It also reflects some of the challenges of disseminating codes of conduct in developing countries and ensuring market benefits from certification. We describe the emergence of forest certification standards, outline current certification schemes, and discuss the role of major corporations in creating demand for certified products. We also discuss the limited success of certification and some of the obstacles to its adoption in developing countries. The current diversity of forest certification programs and ecolabeling schemes has created a costly, less-than-transparent system that has been largely ineffective in terms of the initial goals of reducing tropical deforestation and illegal logging. Some steps have been taken toward harmonization of different certification criteria as well as endorsement and mutual recognition among existing forest certification programs. However, it is unlikely that standardization alone can overcome other, more serious barriers to certification in developing countries.
Deforestation and forest degradation in the tropics is a major source of global greenhouse gas (GHG) emissions. The tropics also harbour more than half the world's threatened species, raising the possibility that reducing GHG emissions by... more
Deforestation and forest degradation in the tropics is a major source of global greenhouse gas (GHG) emissions. The tropics also harbour more than half the world's threatened species, raising the possibility that reducing GHG emissions by curtailing tropical deforestation could provide substantial co-benefits for biodiversity conservation.
Protected areas have numerous roles (such as biodiversity preservation, the development of scientific research and the sustainable use of natural resources), but they are under threat from political and economic forces. The 837 000-ha... more
Protected areas have numerous roles (such as biodiversity preservation, the development of scientific research and the sustainable use of natural resources), but they are under threat from political and economic forces. The 837 000-ha Serra do Divisor National Park (SDNP) in the southwestern Brazilian Amazon combines the conservation of natural resources and the maintenance of the productive activities of c. 400 resident families. The Brazilian and Peruvian governments have proposed a road linking Acre (Brazil) to Ucayali (Peru) that would bisect the SDNP. Another threat to the SDNP is a bill proposing its downgrading to an 'environmental protection area'. This study aims to map the land cover of the SDNP and its surroundings from 1988 to 2018 and to analyse the dynamics of land-use change. Analysis of Landsat satellite images with supervised classification using the MaxVer algorithm show that, during the 30-year period, pasture showed the highest absolute land-cover gain, with 1986 ha in the interior and 7661 ha along the periphery of the SDNP. Only 1% of the park's primary forest was lost by 2018, but the proposed road and potential downgrading may result in accelerated deforestation and forest degradation in the near future.
This paper assesses the role of protected and community managed forests for the long term maintenance of forest cover in the tropics. Through a meta-analysis of published case-studies, we compare land use/ cover change data for these two... more
This paper assesses the role of protected and community managed forests for the long term maintenance of forest cover in the tropics. Through a meta-analysis of published case-studies, we compare land use/ cover change data for these two broad types of forest management and assess their performance in maintaining forest cover. Case studies included 40 protected areas and 33 community managed forests from the peer reviewed literature. A statistical comparison of annual deforestation rates and a Qualitative Comparative Analysis were conducted. We found that as a whole, community managed forests presented lower and less variable annual deforestation rates than protected forests. We consider that a more resilient and robust forest conservation strategy should encompass a regional vision with different land use types in which social and economic needs of local inhabitants, as well as tenure rights and local capacities, are recognized. Further research for understanding institutional arrangements that derive from local governance in favor of tropical forest conservation is recommended.
Monitoring deforestation and forest degradation is central to assessing changes in carbon storage, biodiversity, and many other ecological processes in tropical regions. Satellite remote sensing is the most accurate and cost-effective way... more
Monitoring deforestation and forest degradation is central to assessing changes in carbon storage, biodiversity, and many other ecological processes in tropical regions. Satellite remote sensing is the most accurate and cost-effective way to monitor changes in forest cover and degradation over large geographic areas, but the tools and methods have been highly manual and time consuming, often requiring expert knowledge. We present a new userfriendly, fully automated system called CLASlite, which provides desktop mapping of forest cover, deforestation and forest disturbance using advanced atmospheric correction and spectral signal processing approaches with Landsat, SPOT, and many other satellite sensors. CLASlite runs on a standard Windows-based computer, and can map more than 10,000 km 2 , at 30 m spatial resolution, of forest area per hour of processing time. Outputs from CLASlite include maps of the percentage of live and dead vegetation cover, bare soils and other substrates, along with quantitative measures of uncertainty in each image pixel. These maps are then interpreted in terms of forest cover, deforestation and forest disturbance using automated decision trees. CLASlite output images can be directly input to other remote sensing programs, geographic information systems (GIS), Google Earth™, or other visualization systems. Here we provide a detailed description of the CLASlite approach with example results for deforestation and forest degradation scenarios in Brazil, Peru, and other tropical forest sites worldwide.
KEY WORDS: forest cover change, processed data Updated information of forest resources is vital in proper management and policy formulation from local to national scale. However, data generation regarding forest maps and statistics in the... more
KEY WORDS: forest cover change, processed data Updated information of forest resources is vital in proper management and policy formulation from local to national scale. However, data generation regarding forest maps and statistics in the Philippines is hampered by multiple imagery sources, varying scale and resolutions, undisclosed methods of mapping and different forest classes and definitions used. In this study, processed Landsat forest cover data was analyzed to quantitatively measure the rates of forest loss on the regional level, to analyze its level of applicability and to validate forest changes through various geospatial and other forestry data. Raw data consists of forest tree cover, loss, gain and loss year layers. Five forest vectors were used to extract forest areas from the main data rasters before subsetting them regionally. A forest tree cover threshold of 85 percent and above was used to isolate densely forested rasters. These rasters were further analyzed to produce gain, loss and aggregate net change ranking; annual forest loss and annual forest cover trends, with their corresponding maps and statistics. Among the regions, Zamboanga Peninsula had the highest aggregate net change (-7.18%) followed by CALABARZON (-3.41%) and CARAGA (-3.16%) from 2000-2012. CARAGA had the highest average annual forest loss of-147.53 ha and a correlation of 0.7. On the other hand, Zamboanga and CALABARZON had average annual forest loss which were less than hundred hectares (-73.10 ha and-31.4 ha; r = 0.34 and r = 0.13, respectively). However, only CARAGA had a significant correlation, with p value < 0.05 (0.0098). In terms of annual forest tree cover, CARAGA had the highest average annual forest cover increment of-1,238.16 ha, followed by Zamboanga Peninsula (-830.12 ha) and CALABARZON (-527.61 ha). Forest cover increments exhibited negative values since forest recovery is always outweighed by forest extraction. Error matrix of loss, gain and no change registered an overall accuracy of 86.48% and 92.26%, for loss and gain respectively. Yet, the assessment had lower user accuracy values compared to that of producers'. This might be affected by inadequate high resolution images (mainly Google Earth and Landsat) used in the satellite based validation. The research showed that freely available forest global datasets could be used to pinpoint significant areas where forest loss is occurring. Correlation analysis with other forestry data and field validation through group discussions and interviews may also illustrate insights regarding the drivers of forest loss on a particular area.
Accelerated land use changes in the Brazilian Amazonian region over the last four decades have raised questions about potential consequences for local hydrology. Under the hypothesis of a lack of frontier governance, projections of future... more
Accelerated land use changes in the Brazilian Amazonian region over the last four decades have raised questions about potential consequences for local hydrology. Under the hypothesis of a lack of frontier governance, projections of future changes in the Amazon basin suggest that 20–30% or more of this basin could be deforested in the next 40 years. This could trigger a cascade of negative impacts on water resources. In this study, we examined how a future conversion of the forest into pasture would influence streamflow and water balance components by using a conceptual and semi-distributed hydrological model in a large (142,000 km 2) forested basin: specifically, the Iriri River basin in the Brazilian Amazon. The results showed that the land use change could substantially alter the water balance components of the originally forested basin. For example, an increase of over 57% in pasture areas increased a simulated annual streamflow by ~6.5% and had a significant impact on evapotranspiration, surface runoff, and percolation. Our findings emphasize the importance of protected areas for conservation strategies in the Brazilian Amazonian region.
- by Camila Abe
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- Water, Hydrology, Water resources, Amazonia
Deforestation and land degradation remain two major economic and environmental threats in Côte d’Ivoire. This study assessed land use and land cover (LULC) change and farmers’ perceptions of the drivers and effects of deforestation and... more
Deforestation and land degradation remain two major economic and environmental threats in Côte d’Ivoire. This study assessed land use and land cover (LULC) change and farmers’ perceptions of the drivers and effects of deforestation and land degradation in south-western Côte d’Ivoire. We used remotely sensed data to determine LULC change trends, and a household survey to collect farmers’ perceptions of deforestation and land degradation. A total of 411 households were interviewed using a structured questionnaire and the focus group discussions involved 25 farmers. Landsat image analysis reported a drastic LULC change and a conversion of forestlands into agriculture from 1987 to 2015 at a rate of 1.44%/year and 3.44%/year for dense forests and degraded forests, respectively. The household survey revealed that the major causes of deforestation perceived by farmers included population growth (79.3%), extensive agriculture (72.9%), migration (54.2%) and logging (47.7%). Land degradation evolved, from a shortened fallow period (46.7%) and an inappropriate application of inputs (31.4%). The perceived major effects linked to deforestation encompassed land degradation (70.6%), loss of biodiversity (63.8%), global warming (56.9%) and loss of livelihood assets (54.3%). Therefore, this study recommends participatory landscape planning, reforestation and capacity building of stakeholders for sustainable intensification of the production systems to reduce LULC challenges for enhanced productive and protective functions of remaining forests.
Landscape change occurs through the interaction of a multitude of natural and human driving forces at a range of organisational levels, with humans playing an increasingly dominant role in many regions of the world. Building on the... more
Landscape change occurs through the interaction of a multitude of natural and human driving forces at a range of organisational levels, with humans playing an increasingly dominant role in many regions of the world. Building on the current knowledge of the underlying drivers of landscape change, a conceptual framework of regional landscape change was developed which integrated population, economic and cultural values, policy and science/technology. Using the Southern Brigalow Belt biogeographic region of Queensland as a case study, the role of natural and human drivers in landscape change was investigated in four phases of settlement since 1840. The Brigalow Belt has experienced comparable rates of vegetation clearance over the past 50 years to areas of tropical deforestation. Economic factors were important during all phases of development, but the five regional drivers often acted in synergy. Environmental constraints played a significant role in slowing rates of change. Temporal trends of deforestation followed a sigmoidal curve, with initial slow change accelerating though the middle phases then slowing in recent times. Future landscape management needs to take account of the influence of all the components of the conceptual framework, at a range of organisational levels, if more ecologically sustainable outcomes are to be achieved.
This paper provides a survey of`first wave' economic studies of tropical deforestation and land use. These studies of tropical forest land conversion are generally at the cross-country level. We also conduct a synthesis cross-country... more
This paper provides a survey of`first wave' economic studies of tropical deforestation and land use. These studies of tropical forest land conversion are generally at the cross-country level. We also conduct a synthesis cross-country analysis of tropical agricultural land expansion. The results show that agricultural development is the main factor determining land expansion, but institutional factors have an important influence. Income effects tend to vary from region to region, and do not always display an`Environmental Kuznets Curve' relationship.
The cultivation of cocoa has been an important driver of tropical deforestation globally. Efforts to reverse this trend are focusing on the reintroduction of shade trees to cocoa plantations. Shade trees are valuable in enhancing... more
The cultivation of cocoa has been an important driver of tropical deforestation globally. Efforts to reverse this trend are focusing on the reintroduction of shade trees to cocoa plantations. Shade trees are valuable in enhancing biophysical conditions on cocoa (Theobroma cacao) fields and contribute to biodiversity and product diversification for smallholder producers. Participatory trials of cocoa agroforests planted with indigenous shade tree species were undertaken with farmers in the Atwima District of the Ashanti Region of Ghana, to increase tree volume on cocoa fields while improving rural livelihoods and enhancing environmental sustainability. An ex ante financial analysis of the technology was undertaken to assess its economic viability. Input-output data were collected from farmer experiments over three seasons and supplemented with data from traditional cocoa fields of varying rotation ages, and secondary data on production in later years of an eighty-year cocoa rotation. A discounted cash flow analysis was carried out to estimate the benefit-cost (B/C) ratio, net present value (NPV), internal rate of return (IRR) and land expectation value (LEV) as well as the sensitivity to a 20% decline in cocoa prices and additional chemical costs for various shade scenarios at a 10% discount rate. It was observed that cocoa production is, in general, profitable. The change from the traditional system to one with hybrid cocoa raised the IRR from 31% to 57% with planted shade and 67% without, although extra agrochemical costs would tend to reduce the profitability of unshaded hybrid cocoa in particular. The age of maximum LEV for the various scenarios suggests that the optimum economic rotation for the hybrid cocoa is between 18 and 29 years, much less than the traditional system.
Land cover changes (LCC) affect the water balance (WB), changing surface runoff (SurfQ), evapotranspiration (ET), groundwater (GW) regimes, and streamflow (Q). The Tapajós Basin (southeastern Amazon) has experienced LCC over the last 40... more
Land cover changes (LCC) affect the water balance (WB), changing surface runoff (SurfQ), evapotranspiration (ET), groundwater (GW) regimes, and streamflow (Q). The Tapajós Basin (southeastern Amazon) has experienced LCC over the last 40 years, with increasing LCC rates projected for the near future. Several studies have addressed the effects of climate changes on the region's hydrology, but few have explored the effects of LCC on its hydrological regime. In this study, the Soil and Water Assessment Tool (SWAT) was applied to model the LCC effects on the hydrology of the Upper Crepori River Basin (medium Tapajós Basin), using historical and projected LCC based on conservation policies (GOV_2050) and on the " Business as Usual " trend (BAU_2050). LCC that occurred from 1973 to 2012, increased Q by 2.5%, without noticeably altering the average annual WB. The future GOV_2050 and BAU_2050 scenarios increased SurfQ by 238.87% and 300.90%, and Q by 2.53% and 2.97%, respectively, and reduced GW by 4.00% and 5.21%, and ET by 2.07% and 2.43%, respectively. Results suggest that the increase in deforestation will intensify floods and low-flow events, and that the conservation policies considered in the GOV_2050 scenario may still compromise the region's hydrology at a comparable level to that of the BAU_2050.
El cultivo de palma africana está asociado a impactos más que significativos a nivel tanto ambiental como social. Estos mismos impactos han sido atribuidos al caso mexicano en general y a la Selva Lacandona en particular. Este estudio... more
El cultivo de palma africana está asociado a impactos más que significativos a nivel tanto ambiental como social. Estos mismos impactos han sido atribuidos al caso mexicano en general y a la Selva Lacandona en particular. Este estudio ofrece datos para el caso del sureste de la Selva Lacandona, y en concreto para los municipios de Marqués de Comillas y Benemérito de las Américas. Los resultados aquí presentados indican que el cultivo de palma africana se ha expandido principalmente a costa de la ganadería, especialmente en el caso de familias de ingresos medios y bajos. Las restricciones en cuanto a inversiones laborales y de capital que enfrentan los productores, así como la orientación agro-industrial que ha seguido el esquema de promoción del cultivo ha favorecido el uso de agroquímicos, particularmente herbicidas. Aunque el uso de los mismos es por el momento limitado, su incremento o uso continuado tendría efectos deletéreos en la salud de las familias campesinas así como en el ambiente. A diferencia de otras regiones del mundo, la compra de tierras para siembra de palma africana se ha visto limitada por la existencia de la tenencia ejidal, elemento clave para evitar deforestación y vulnerabilidad social. Existe poca atención a la situación de los trabajadores, un sector prácticamente invisible, y cuyos derechos deben ser garantizados. Este estudio recomienda la certificación RSPO para controlar o reducir impactos. Esta certificación es en cualquier caso insuficiente y se deben hacer modificaciones a las políticas públicas relacionadas con este cultivo para de este modo garantizar un desarrollo sustentable. Este proceso podría ser fortalecido por la industria nacional alimentaria que, por el momento y como en el pasado para la ganadería, no ha llevado a cabo esfuerzos significativos en la consecución de la sustentabilidad en la región.
While the global community is seeking to reduce fossil fuel consumption, a parallel but equally important issue is the environmental impacts of increased world consumption of beef. We provide a comparative analysis and synthesis of the... more
While the global community is seeking to reduce fossil fuel consumption, a parallel but equally important issue is the environmental impacts of increased world consumption of beef. We provide a comparative analysis and synthesis of the expansion of beef cattle production and its regional and global environmental impacts for Queensland (Australia), Colombia and Brazil. Evidence assembled indicates that rising beef consumption is a major driver of regional and global change, and warrants greater policy attention. We propose four policy imperatives to help mitigate escalating environmental impacts of beef: stop subsidising beef production and promoting beef consumption; control future expansion of soybeans and extensive grazing; protect and restore regrowth forests in grazing lands; and allocate resources to less environmentally damaging alternative land uses. ß
As part of an effort to develop a comprehensive management plan for the Imbak Canyon Conservation Area in central Sabah, Malaysian Borneo, we conducted a rapid but extensive mammal survey using camera-trapping techniques. We gathered... more
As part of an effort to develop a comprehensive management plan for the Imbak Canyon Conservation Area in central Sabah, Malaysian Borneo, we conducted a rapid but extensive mammal survey using camera-trapping techniques. We gathered baseline data on mammal species richness and community composition, as well as information on activity patterns for some mammal species. Eighty motion-triggered digital camera-traps were set in the primary and logged forests in and around the Imbak Canyon. The total accumulated camera-trapping effort of 1,436 camera trap-nights yielded 1,641 digital photographs of mammals represented by 27 species in 14 families and fi ve orders. The species photo-captured included common species, as well as rare and elusive species and species that are of high conservation value, such as the Sunda clouded leopard, Neofelis diardi and orang utan, Pongo pygmaeus. Our results indicated that the primary forest of the Imbak Canyon and its surrounding disturbed forests are important habitats for mammal conservation. Of particular importance are the carnivores, with 13 species recorded. Game animals, such as bearded pig, Sus barbatus, muntjac, Muntiacus spp., and mousedeer, Tragulus spp., were found to be among the most frequently photo-captured and the most widespread species. The activity patterns of mammals investigated did not show that they were affected by human activities. Even so, we found substantial evidence of poaching and illegal collection of the aromatic gaharu tree resin (Aquilaria spp.) in the surveyed areas, raising management concerns and highlighting the urgent need for law enforcement activities in the area.
Qui a déforesté l'Afrique centrale : l'Homme ou le climat ? Scientific news Actualidad cientifica Actualité scientifique Les premiers agriculteurs Bantous, qui ont colonisé les forêts d'Afrique centrale il y a 2 500 ans, les ont-ils en... more
Qui a déforesté l'Afrique centrale : l'Homme ou le climat ? Scientific news Actualidad cientifica Actualité scientifique Les premiers agriculteurs Bantous, qui ont colonisé les forêts d'Afrique centrale il y a 2 500 ans, les ont-ils en même temps fortement défrichées, comme cela a été avancé récemment ? Ou bien ont-ils simplement bénéficié d'un changement climatique brutal qui a fragmenté le bloc forestier et leur a ainsi permis d'y pénétrer plus facilement ? Plusieurs spécialistes de l'IRD et leurs partenaires 1 archéologues, paléoenvironnementalistes et palynologues 2 défendent l'hypothèse climatique dans la revue Science. Les fouilles archéologiques (ici au Cameroun) ont révélé que la civilisation bantoue a colonisé la sous-région bien après que la forêt ait laissé place à la savane (entre savane et forêt en République centrafricaine au milieu). A droite, brûlis en forêt au Gabon. Contacts Jean Maley, directeur de recherche honoraire de l'IRD
Mining is a significant driver of deforestation. Not only do mines clear native forests for mineral extraction, they also often establish new infrastructure, which indirectly facilitates new access to land and further clearing. Forest... more
Mining is a significant driver of deforestation. Not only do mines clear native forests for mineral extraction, they also often establish new infrastructure, which indirectly facilitates new access to land and further clearing. Forest loss and fragmentation have serious effects on biodiversity, yet rarely are these cumulative impacts of mining studied at the regional scale. Here, we examine potential impacts of mining in a biodiverse region of the Brazilian Amazon. The National Reserve of Copper and Associates (“Renca”) is currently off limits to mining activities but was recently threatened with a move to permit mineral exploration. We analyzed historic forest loss and fragmentation within two mining regions neighboring Renca to explore what might happen if Renca were to be mined. We also investigated historic deforestation trajectories within Renca’s protected areas, to determine how well conserved these forests are against current threats. We found that mining, and other infrastructure associated with mines (i.e. roads), caused significant forest loss and fragmentation within neighboring mining sectors, and that Renca’s protected areas are not currently immune to forest loss. Permitting new mines within and surrounding Renca will place additional pressure on its biodiversity. If mineral development is to proceed, huge regulatory changes will be required to effectively manage negative impacts on forests and biodiversity. Environmental Impact Assessments for new mining projects must assess and mitigate the cumulative region-wide effects on forests, while existing protected areas must be strengthened to ensure they are not directly or indirectly compromised by mining activities
As part of an effort to develop a comprehensive management plan for the Imbak Canyon Conservation Area in central Sabah, Malaysian Borneo, we conducted a rapid but extensive mammal survey using camera-trapping techniques. We gathered... more
As part of an effort to develop a comprehensive management plan for the Imbak Canyon Conservation Area in central Sabah, Malaysian Borneo, we conducted a rapid but extensive mammal survey using camera-trapping techniques. We gathered baseline data on mammal species richness and community composition, as well as information on activity patterns for some mammal species. Eighty motion-triggered digital camera-traps were set in the primary and logged forests in and around the Imbak Canyon. The total accumulated camera-trapping effort of 1,436 camera trap-nights yielded 1,641 digital photographs of mammals represented by 27 species in 14 families and fi ve orders. The species photo-captured included common species, as well as rare and elusive species and species that are of high conservation value, such as the Sunda clouded leopard, Neofelis diardi and orang utan, Pongo pygmaeus. Our results indicated that the primary forest of the Imbak Canyon and its surrounding disturbed forests are important habitats for mammal conservation. Of particular importance are the carnivores, with 13 species recorded. Game animals, such as bearded pig, Sus barbatus, muntjac, Muntiacus spp., and mousedeer, Tragulus spp., were found to be among the most frequently photo-captured and the most widespread species. The activity patterns of mammals investigated did not show that they were affected by human activities. Even so, we found substantial evidence of poaching and illegal collection of the aromatic gaharu tree resin (Aquilaria spp.) in the surveyed areas, raising management concerns and highlighting the urgent need for law enforcement activities in the area. KEY WORDS.-camera trapping, Imbak Canyon, mammal species richness, activity patterns.