scholarly journals Congo Basin forest loss dominated by increasing smallholder clearing

2018 ◽  
Vol 4 (11) ◽  
pp. eaat2993 ◽  
Author(s):  
Alexandra Tyukavina ◽  
Matthew C. Hansen ◽  
Peter Potapov ◽  
Diana Parker ◽  
Chima Okpa ◽  
...  
Keyword(s):  
Population Growth ◽  
Large Scale ◽  
Forest Cover ◽  
Forest Type ◽  
Forest Disturbance ◽  
Timber Harvesting ◽  
Selective Logging ◽  
Congo Basin ◽  
Small Scale ◽  
Forest Loss

A regional assessment of forest disturbance dynamics from 2000 to 2014 was performed for the Congo Basin countries using time-series satellite data. Area of forest loss was estimated and disaggregated by predisturbance forest type and direct disturbance driver. An estimated 84% of forest disturbance area in the region is due to small-scale, nonmechanized forest clearing for agriculture. Annual rates of small-scale clearing for agriculture in primary forests and woodlands doubled between 2000 and 2014, mirroring increasing population growth. Smallholder clearing in the Democratic Republic of the Congo alone accounted for nearly two-thirds of total forest loss in the basin. Selective logging is the second most significant disturbance driver, contributing roughly 10% of regional gross forest disturbance area and more than 60% of disturbance area in Gabon. Forest loss due to agro-industrial clearing along the Gulf of Guinea coast more than doubled in the last half of the study period. Maintaining natural forest cover in the Congo Basin into the future will be challenged by an expected fivefold population growth by 2100 and allocation of industrial timber harvesting and large-scale agricultural development inside remaining old-growth forests.

Economic crisis, small-scale agriculture, and forest cover change in southern Cameroon

2000 ◽  
Vol 27 (3) ◽  
pp. 284-290 ◽  
Author(s):  
W.D. SUNDERLIN ◽  
O. NDOYE ◽  
H. BIKIÉ ◽  
N. LAPORTE ◽  
B. MERTENS ◽  
...  
Keyword(s):  
Population Growth ◽  
Economic Crisis ◽  
Rural Population ◽  
Structural Adjustment ◽  
Large Scale ◽  
Forest Cover ◽  
Small Scale ◽  
Forest Cover Change ◽  
Macroeconomic Shocks ◽  
Adjustment Policies

The rate of forest cover loss in the humid tropics of Cameroon is one of the highest in Central Africa. The aim of the large-scale, two-year research project described here was to understand the effect of the country's economic crisis and policy change on small-scale agricultural systems and land-clearing practices. Hypotheses were tested through surveys of more than 5000 households in 125 villages, and through time-series remote sensing analysis at two sites. The principal findings are that: (1) the rate of deforestation increased significantly in the decade after the 1986 onset of the crisis, as compared to the decade prior to the crisis; (2) the main proximate causes of this change were sudden rural population growth and a shift from production of cocoa and coffee to plantain and other food crops; and (3) the main underlying causes were macroeconomic shocks and structural adjustment policies that led to rural population growth and farming system changes. The implication of this study is that it is necessary to understand and anticipate the undesirable consequences of macroeconomic shocks and adjustment policies for forest cover. Such policies, even though they are often not formulated with natural resource consequences in mind, are often of greater relevance to the fate of forests than forest policy.

scholarly journals The national determinants of deforestation in sub-Saharan Africa

2013 ◽  
Vol 368 (1625) ◽  
pp. 20120405 ◽  
Author(s):  
Thomas K. Rudel
Keyword(s):  
Forest Cover ◽  
Driving Forces ◽  
National Level ◽  
Congo Basin ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Urban Migration ◽  
Forest Cover Change ◽  
Level Data ◽  
Sub Saharan

For decades, the dynamics of tropical deforestation in sub-Saharan Africa (SSA) have defied easy explanation. The rates of deforestation have been lower than elsewhere in the tropics, and the driving forces evident in other places, government new land settlement schemes and industrialized agriculture, have largely been absent in SSA. The context and causes for African deforestation become clearer through an analysis of new, national-level data on forest cover change for SSA countries for the 2000–2005 period. The recent dynamic in SSA varies from dry to wet biomes. Deforestation occurred at faster rates in nations with predominantly dry forests. The wetter Congo basin countries had lower rates of deforestation, in part because tax receipts from oil and mineral industries in this region spurred rural to urban migration, declines in agriculture and increased imports of cereals from abroad. In this respect, the Congo basin countries may be experiencing an oil and mineral fuelled forest transition. Small farmers play a more important role in African deforestation than they do in southeast Asia and Latin America, in part because small-scale agriculture remains one of the few livelihoods open to rural peoples.

Causes and history of forest loss in Cambodia

2019 ◽  
Vol 21 (3) ◽  
pp. 372-384 ◽  
Author(s):  
R. TSUJINO ◽  
T. KAJISA ◽  
T. YUMOTO
Keyword(s):  
Forest Cover ◽  
Arable Land ◽  
Growth Period ◽  
Rapid Expansion ◽  
Small Scale ◽  
Forest Loss ◽  
Rapid Economic Growth ◽  
History Of ◽  
Post War ◽  
The 1960S

To reconstruct the history of forest loss in Cambodia, the literature and national/provincial statistics of landuse patterns and the socio-economic situation were investigated. Forest cover in the 1960s was 73.3 % (13.3 Mha). However, this drastically decreased to 47.3% (8.6 Mha) in 2016. In the 1960s, the forest was less-disturbed. From 1970 to 1993, the forest was lost gradually owing to the political instability caused by the Cambodian Civil War. In the post-war reconstruction period from 1993 to around 2002, the need for reconstruction, international demand for timber, and forest logging concessions led to a significant increase in timber production. In the rapid economic growth period from 2002 until present, while several political actions were taken to combat rapid deforestation, economic land concessions, which promoted agroindustrial plantations, as well as small-scale agriculture has been leading to the rapid expansion of arable land and deforestation since 2009.

scholarly journals Analyses of Land Cover Change Trajectories Leading to Tropical Forest Loss: Illustrated for the West Kutai and Mahakam Ulu Districts, East Kalimantan, Indonesia

Land ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 108 ◽  
Author(s):  
Carina van der Laan ◽  
Arif Budiman ◽  
Judith Verstegen ◽  
Stefan Dekker ◽  
Wiwin Effendy ◽  
...  
Keyword(s):  
Land Cover ◽  
Land Cover Change ◽  
Large Scale ◽  
Expert Knowledge ◽  
Small Scale ◽  
Forest Loss ◽  
The West ◽  
East Kalimantan ◽  
Open Forest ◽  
Over Time

In Indonesia, land cover change for agriculture and mining is threatening tropical forests, biodiversity and ecosystem services. However, land cover change is highly dynamic and complex and varies over time and space. In this study, we combined Landsat-based land cover (change) mapping, pixel-to-pixel cross tabulations and expert knowledge to analyze land cover change and forest loss in the West Kutai and Mahakam Ulu districts in East Kalimantan from 1990–2009. We found that about one-third of the study area changed in 1990–2009 and that the different types of land cover changes in the study area increased and involved more diverse and characteristic trajectories in 2000–2009, compared to 1990–2000. Degradation to more open forest types was dominant, and forest was mostly lost due to trajectories that involved deforestation to grasslands and shrubs (~17%), and to a lesser extent due to trajectories from forest to mining and agriculture (11%). Trajectories from forest to small-scale mixed cropland and smallholder rubber occurred more frequently than trajectories to large-scale oil palm or pulpwood plantations; however, the latter increased over time. About 11% of total land cover change involved multiple-step trajectories and thus “intermediate” land cover types. The combined trajectory analysis in this paper thus contributes to a more comprehensive analysis of land cover change and the drivers of forest loss, which is essential to improve future land cover projections and to support spatial planning.

scholarly journals Resource extraction and infrastructure threaten forest cover and community rights

2018 ◽  
Vol 115 (52) ◽  
pp. 13164-13173 ◽  
Author(s):  
Anthony J. Bebbington ◽  
Denise Humphreys Bebbington ◽  
Laura Aileen Sauls ◽  
John Rogan ◽  
Sumali Agrawal ◽  
...  
Keyword(s):  
Forest Cover ◽  
Resource Extraction ◽  
Small Scale ◽  
Forest Loss ◽  
Growth Strategies ◽  
Conservation Areas ◽  
Population Movements ◽  
Cross Border ◽  
Forested Areas ◽  
Potential Resource

Mineral and hydrocarbon extraction and infrastructure are increasingly significant drivers of forest loss, greenhouse gas emissions, and threats to the rights of forest communities in forested areas of Amazonia, Indonesia, and Mesoamerica. Projected investments in these sectors suggest that future threats to forests and rights are substantial, particularly because resource extraction and infrastructure reinforce each other and enable population movements and agricultural expansion further into the forest. In each region, governments have made framework policy commitments to national and cross-border infrastructure integration, increased energy production, and growth strategies based on further exploitation of natural resources. This reflects political settlements among national elites that endorse resource extraction as a pathway toward development. Regulations that protect forests, indigenous and rural peoples’ lands, and conservation areas are being rolled back or are under threat. Small-scale gold mining has intensified in specific locations and also has become a driver of deforestation and degradation. Forest dwellers’ perceptions of insecurity have increased, as have documented homicides of environmental activists. To explain the relationships among extraction, infrastructure, and forests, this paper combines a geospatial analysis of forest loss overlapped with areas of potential resource extraction, interviews with key informants, and feedback from stakeholder workshops. The increasing significance of resource extraction and associated infrastructure as drivers of forest loss and rights violations merits greater attention in the empirical analyses and conceptual frameworks of Sustainability Science.

scholarly journals Object-Based Classification of Forest Disturbance Types in the Conterminous United States

2019 ◽  
Vol 11 (5) ◽  
pp. 477 ◽  
Author(s):  
Lian-Zhi Huo ◽  
Luigi Boschetti ◽  
Aaron Sparks
Keyword(s):  
United States ◽  
Forest Cover ◽  
Forest Disturbance ◽  
Global Scale ◽  
Management Policy ◽  
Forest Loss ◽  
Forest Cover Change ◽  
Forest Change ◽  
Goods And Services ◽  
Moderate Resolution Imaging Spectroradiometer

Forest ecosystems provide critical ecosystem goods and services, and any disturbance-induced changes can have cascading impacts on natural processes and human socioeconomic systems. Forest disturbance frequency, intensity, and spatial and temporal scale can be altered by changes in climate and human activity, but without baseline forest disturbance data, it is impossible to quantify the magnitude and extent of these changes. Methodologies for quantifying forest cover change have been developed at the regional-to-global scale via several approaches that utilize data from high (e.g., IKONOS, Quickbird), moderate (e.g., Landsat) and coarse (e.g., Moderate Resolution Imaging Spectroradiometer (MODIS)) spatial resolution satellite imagery. While detection and quantification of forest cover change is an important first step, attribution of disturbance type is critical missing information for establishing baseline data and effective land management policy. The objective here was to prototype and test a semi-automated methodology for characterizing high-magnitude (>50% forest cover loss) forest disturbance agents (stress, fire, stem removal) across the conterminous United States (CONUS) from 2003–2011 using the existing University of Maryland Landsat-based Global Forest Change Product and Web-Enabled Landsat Data (WELD). The Forest Cover Change maps were segmented into objects based on temporal and spatial adjacency, and object-level spectral metrics were calculated based on WELD reflectance time series. A training set of objects with known disturbance type was developed via high-resolution imagery and expert interpretation, ingested into a Random Forest classifier, which was then used to attribute disturbance type to all 15,179,430 forest loss objects across CONUS. Accuracy assessments of the resulting classification was conducted with an independent dataset consisting of 4156 forest loss objects. Overall accuracy was 88.1%, with the highest omission and commission errors observed for fire (32.8%) and stress (31.9%) disturbances, respectively. Of the total 172,686 km2 of forest loss, 83.75% was attributed to stem removal, 10.92% to fire and 5.33% to stress. The semi-automated approach described in this paper provides a promising framework for the systematic characterization and monitoring of forest disturbance regimes.

scholarly journals Assessment of Large Scale Land Cover Change Classifications and Drivers of Deforestation in Indonesia

2015 ◽  
Vol XL-7/W3 ◽  
pp. 557-562 ◽  
Author(s):  
A. Wijaya ◽  
R. A. Sugardiman Budiharto ◽  
A. Tosiani ◽  
D. Murdiyarso ◽  
L.V. Verchot
Keyword(s):  
Land Cover ◽  
Large Scale ◽  
Forest Cover ◽  
Spatial Information ◽  
Brazilian Amazon ◽  
Congo Basin ◽  
Reliable Estimate ◽  
Forest Conversion ◽  
Forest Cover Change ◽  
Forest Change

Indonesia possesses the third largest tropical forests coverage following Brazilian Amazon and Congo Basin regions. This country, however, suffered from the highest deforestation rate surpassing deforestation in the Brazilian Amazon in 2012. National capacity for forest change assessment and monitoring has been well-established in Indonesia and the availability of national forest inventory data could largely assist the country to report their forest carbon stocks and change over more than two decades. This work focuses for refining forest cover change mapping and deforestation estimate at national scale applying over 10,000 scenes of Landsat scenes, acquired in 1990, 1996, 2000, 2003, 2006, 2009, 2011 and 2012. Pre-processing of the data includes, geometric corrections and image mosaicking. The classification of mosaic Landsat data used multi-stage visual observation approaches, verified using ground observations and comparison with other published materials. There are 23 land cover classes identified from land cover data, presenting spatial information of forests, agriculture, plantations, non-vegetated lands and other land use categories. We estimated the magnitude of forest cover change and assessed drivers of forest cover change over time. Forest change trajectories analysis was also conducted to observe dynamics of forest cover across time. This study found that careful interpretations of satellite data can provide reliable information on forest cover and change. Deforestation trend in Indonesia was lower in 2000-2012 compared to 1990-2000 periods. We also found that over 50% of forests loss in 1990 remains unproductive in 2012. Major drivers of forest conversion in Indonesia range from shrubs/open land, subsistence agriculture, oil palm expansion, plantation forest and mining. The results were compared with other available datasets and we obtained that the MOF data yields reliable estimate of deforestation.

scholarly journals Degradation of visible autumn icons and conservation opportunities: trends in deciduous forest loss in the contiguous US

2021 ◽  
Author(s):  
Lindsay M Dreiss ◽  
Jacob W Malcom
Keyword(s):  
Protected Areas ◽  
Forest Cover ◽  
Deciduous Forest ◽  
Forest Disturbance ◽  
The United States ◽  
Environmental Stability ◽  
Forest Loss ◽  
Conservation Action ◽  
Worst Case ◽  
Temperate Deciduous Forests

Temperate deciduous forests are one of the most visible biomes on Earth because of their autumn aesthetics and because they harbor some of the most heavily populated regions, including in the United States. Their location and their ability to attract leaf-peeping outsiders may provide greater opportunities for people to experience nature, which has been linked to greater conservation action. However, accelerating human modification of landscapes means continued forest loss and fragmentation. We use spatial overlay analyses to quantify recent (1984-2016) and predicted (2016-2050) forest disturbance in each U.S. ecoregion and the extent to which each ecoregion falls into protected areas. Almost all ecoregions saw a steady decline in deciduous forest cover between 1985 and 2016 with some of the top ecoregions for autumn aesthetics being underrepresented in the protected areas network and vulnerable to additional losses. Generally, ecoregions undergoing greater proportional losses have greater forest area and are less represented in the protected areas network. Under worst-case forecasting scenarios, losses are predicted to continue. However, environmentally focused scenarios suggest there is still opportunity to reverse deciduous forest loss in some ecoregions. The large difference in forest loss estimates in the predictions scenarios emphasizes the importance of human approaches to economic growth and sustainability in securing environmental stability. Increasing public exposure to temperate forests may help ensure conservation of more natural areas and preserve the quantity and quality of autumn forest viewing.

scholarly journals Assessment of the CLASlite forest monitoring system in detecting disturbance from selective logging in the Selva Maya, Mexico

Silva Fennica ◽  
2019 ◽  
Vol 53 (1) ◽  
Author(s):  
Irving Hernández-Gómez ◽  
Carlos Cerdán ◽  
Angélica Navarro-Martínez ◽  
Dinora Vázquez-Luna ◽  
Samaria Armenta-Montero ◽  
...  
Keyword(s):  
Monitoring System ◽  
Forest Disturbance ◽  
Road Construction ◽  
Timber Harvesting ◽  
Selective Logging ◽  
Reference Points ◽  
Forest Monitoring ◽  
Landsat Images ◽  
Community Forests ◽  
Logging Impacts

Detecting and monitoring forest disturbance from selective logging is necessary to develop effective strategies and polices that conserve tropical forests and mitigate climate change. We assessed the potential of using the remote sensing tool, CLASlite forest monitoring system, to detect disturbance from timber harvesting in four community forests () of the Selva Maya on the Yucatan Peninsula, Mexico. Selective logging impacts (e.g. felling gaps, skid trails, logging roads and log landings) were mapped using GPS in the 2014 annual cutting areas (ACAs) of each ejido. We processed and analyzed two pre-harvest Landsat images (2001 and 2013) and one post-harvest image (November 2014) with the CLASlite system, producing maps of degraded, deforested and unlogged areas in each ACA. Based on reference points of disturbed (felling and skidding), deforested (log landings and roads) and unlogged areas in each ACA, we applied accuracy assessments which showed very low overall accuracies (<19.1%). Selective logging impacts, mainly from log landings and new logging road construction, were detected in only one ejido which had the highest logging intensity (7 m ha).ejidos3–1

scholarly journals Mapping Forest Disturbance Due to Selective Logging in the Congo Basin with RADARSAT-2 Time Series

2021 ◽  
Vol 13 (4) ◽  
pp. 740
Author(s):  
Oleg Antropov ◽  
Yrjö Rauste ◽  
Jaan Praks ◽  
Frank Martin Seifert ◽  
Tuomas Häme
Keyword(s):  
Time Series ◽  
Change Detection ◽  
Forest Disturbance ◽  
Selective Logging ◽  
Congo Basin ◽  
Optical Data ◽  
Textural Features ◽  
Before And After ◽  
Disturbed Forest ◽  
Log Ratio

Dense time series of stripmap RADARSAT-2 data acquired in the Multilook Fine mode were used for detecting and mapping the extent of selective logging operations in the tropical forest area in the northern part of the Republic of the Congo. Due to limited radiometric sensitivity to forest biomass variation at C-band, basic multitemporal change detection approach was supplemented by spatial texture analysis to separate disturbed forest from intact. The developed technique primarily uses multi-temporal aggregation of orthorectified synthetic aperture radar (SAR) imagery that are acquired before and after the logging operations. The actual change analysis is based on textural features of the log-ratio image calculated using two SAR temporal composites compiled of SAR scenes acquired before and after the logging operations. Multitemporal aggregation and filtering of SAR scenes decreased speckle and made the extracted textural features more prominent. The overall detection accuracy was around 80%, with some underestimation of the area of forest disturbance compared to reference based on optical data. The user’s accuracy for disturbed forest varied from 76.7% to 94.9% depending on the accuracy assessment approach. We conclude that change detection utilizing RADARSAT-2 time series represents a useful instrument to locate areas of selective logging in tropical forests.

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