Loss Of Forest Area Research Articles

Analysis of coastline change in relation to meteorological conditions and human activities in Ca mau cape, Viet Nam

Ca Mau Cape is a part of Ngoc Hien district and is the southernmost tip of inland Vietnam. The district is highly vulnerable to coastal processes induced by natural and human factors that play important role in shaping and controlling the coastline. This study investigated the coastline change over 20 years, 1990–2010, in relation to meteorological conditions and human interventions using the land-use map (Landsat TM) and questionnaire survey. During this period, Ngoc Hien lost 2206 ha of coastal zone due to erosion. Most of the erosion occurred in the communes located in the east coast side. Remarkable changes in land-use/land-cover patterns were observed with a substantial reduction in the forest and increase in the aquaculture farming land. The results of the technical data analysis and questionnaire survey showed that both meteorological conditions and human interventions were interacted to cause the changes. Although the impacts of individual factors could not be readily quantified, the most important factors causing the coastline changes were forest area loss, river dredging, aquaculture and infrastructure development. The scientific information obtained in this study can be used to develop sustainable coastal management strategies for the study area.

The effects of urbanization on China's forest loss from 2000 to 2012: Evidence from a panel analysis

Forest loss has severe impacts on global environment change and biodiversity. However, few studies have used panel models to analyze forest loss at the national level, attributed to the limited time-space-series data on the forest loss at such large scale. The freely accessible Landsat images provide data to derive the global forest loss at a high spatial resolution of 30 m (Hansen et al., 2013), which make it possible to carry out this study. Here we used the global forest loss dataset as a data source, a space-time panel model for 31 provinces, autonomous regions, or municipalities in mainland of China from 2000 to 2012 were built to investigate the relationship between the urbanization process and the forest loss both at the national and regional level. The results indicated that (1) the forest loss area of each province were between 3 and 89 ha to more than 89 ha during 2001 and 2012, with larger area of forest loss in the southern and north-eastern regions, while less forest loss in the central and western region. (2) In the study period, the forest loss rates were more than 4% in the southern China, while the rates were less than 0.1% in most of the northwest China; and the annual forest loss demonstrated an aggravated trend in most provinces of China. (3) There exists a scale effect and regional divergence in the impact of urbanization on forest loss: urbanization level is among the most critical factor affecting forest loss at the national level; while at the regional level, the most sensitive factor for forest loss is road mileage in the eastern region, urban green area in the central region, while urban level in the western region. This study may help to advance the understanding of the impact of urbanization process on China's forest loss, and therefore it provides good policy implications to make more effective and comprehensive solutions to reduce the loss of forests.

Biodiversity conservation through indigenous agricultural practices: Woody species composition, density and diversity along an altitudinal gradient of Northern Ethiopia

AbstractThe greatest human impact on the forest ecosystems such as loss of forest area, habitat fragmentation, and soil degradation leads to decline biodiversity. These impacts can be addressed by ...

Over-Agglomeration and Its Effects on Sustainable Development: A Case Study on Istanbul

Inequality, in any form and dimension, is a major damaging factor for sustainable development. One of the essential drivers of inequality is the over-agglomeration and congestion in a certain region. The reasons for the agglomeration are well documented, such as knowledge-spillovers, access to supply and demand markets, availability of skilled labor, and good infrastructure. However, over-agglomeration in a region, mainly triggered by poor planning and mismanagement of resource allocation, may also become a barrier for sustainable development. The over-agglomeration generally results in undesired negative effects impeding the economic, social, and environmental development any further, even causing irreversible social and environmental issues. Following the big-push model, a theoretical model is proposed to consider the negative effects of increasing rent prices due to over-agglomeration first on the industrial development of a country. This is then followed by a case study of Istanbul as a megacity and its effects on Turkey’s sustainable development through industrial, social, and ecological aspects. Istanbul has been the main industrial and economic center of Turkey as the city further expanded rapidly in the last 50 years in terms of population and urbanization. This over-agglomeration has resulted in very high rent prices in the city compared to the rest of Turkey, which affected the country’s industrialization. The over-agglomeration in Istanbul has also created significant economic imbalances and income-inequalities within the city and across Turkey. The environmental degradation, the loss of forest area, and very high air and noise pollution were other results of the city’s rapid expansion and over-agglomeration. These industrial, social, and environmental dynamics pose serious challenges to Turkey’s sustainable development as long as over-agglomeration in Istanbul persists or even aggravates further.

Assessing the impact of mining on deforestation in India

We explore the role of mining in contributing to deforestation across 300 plus districts in India. Using a unique dataset, covering the period 2001–2014, the impact of mining related deforestation is delineated from those driven by various socio-economic, demographic and climatic factors. The roles of several minerals, such as coal, iron, bauxite, dolomite, limestone, manganese, quartz, fireclay and granite are explicitly tested using econometric analysis. Findings indicate that, on average, a district that did not produce any of the minerals considered in the study had suffered about 350 km2 lower forest area loss compared to a mineral producing district. Districts that produced coal, iron or limestone, saw on average 450 km2 higher forest cover loss compared to those that did not produce the same minerals. Iron ore production was positively associated with barren land area across districts, whereas forest cover loss was higher in districts that produced higher amounts of limestone or granite. Overall, mining has evidently contributed to deforestation at a district level, and within the mineral groups considered in this study, coal, iron and limestone have had the most adverse impact on forest area loss. However, minerals such as fireclay, manganese, dolomite, and quartz are being produced in districts that have seen either a lower deforestation rate or an improvement in forest area over the study period. Among the non-mining related drivers of deforestation, higher share of cropping area in a district's geographical area significantly contributed to deforestation.

Impact of land use land cover change on ecosystem services: a comparative analysis on observed data and people\u2019s perception in Inle Lake, Myanmar

BackgroundA healthy wetland provides a range of goods and services contributing to human wellbeing. Inle Lake, the first Biosphere Reserve in Myanmar, has been supporting the local inhabitants with ecosystem services (ES) including habitat for a wide range of biodiversity. In the recent years, influenced by land use land cover change (LULCC), the lake has witnessed changes with altered flow of ES, affecting human well-being. Communities’ perceptions are often undermined, when it comes to research LULCC. We analyzed LULCC change data from 1989–2000 to 2000–2014 using Landsat imageries. This was then linked to ES considering dependency through qualitative data collated from participatory rural appraisal tools and structured questionnaires focusing on people’s perception to understand the LULCC dynamics and its implication.ResultsDuring 25 years (1989–2014), there has been a sharp reduction of 164 km2 perennial wetland area in the Inle Lake, which is 4.2-fold higher in 2014 to that of 1989. Similarly, forest area has been declined by 92 km2 (8.56%) in last 25 years. Contrary to this, cropland area showed an increment of 60.67% in 2000 and 64.53% in the year 2014 alone giving a total increase by 268 km2 over the last 25 years and an expansion of 40 km2 seasonal freshwater area were observed showing periodic increment over the time. Communities from the three study areas, namely, Kyaung Taung, Zay Gon and Kyar Taw are found to have high dependence in their surrounding ecosystems. These villages utilizes 17 ES from forest ecosystem, 13 from agro-ecosystem, 10 from seasonal and 4 from perennial water body for their livelihood respectively. Around 93% of the respondents opined that forest ecosystem has decreased over the last 10 years. Around 40% of the respondents reflected an increase in area used for cropland; 43% conversely perceived a declination. About 63% of the respondents perceived such changes have brought huge reduction in availability of freshwater ES. A significant number of respondents (92%) perceived an enormous reduction in seasonal water body during the dry season.ConclusionObserved decreasing trends in forest and perennial wetland areas were consistent with people’s perceived changes. Communities associate loss of forest and wetland area with reduced availability of ES as well as degraded health of the lake.

Quantifying the trade-off between cost and precision in estimating area of forest loss and degradation using probability sampling in Guyana

Guyana is a high forest cover, low deforestation country. Since 2011–2014 the Guyana Forestry Commission (GFC) has used visual interpretation of 5 m resolution RapidEye imagery to map forest loss and nearby degradation for the entire country. According to the GFC produced national map, 58% of all forest loss events cover less than 1 ha, so forest loss is very rare and occurs at a scale that can be difficult to detect and monitor. Nearly all (~97%) of the forest loss and nearby degradation is due to small-scale mining and its associated infrastructure. For any country wanting to accurately map and monitor forest loss, sample-based area estimation can be considerably less expensive than wall-to-wall mapping. To quantify the tradeoff between precision and cost, we evaluated the standard errors of area estimators for several sample-based strategies using Guyana as a case study. We partitioned Guyana into 374 blocks, with each block 24 km × 24 km to align with the image tiles provided by RapidEye's 3A product. The area of forest loss and area of degradation for each of the 374 blocks were determined from the GFC map to create the population data used to evaluate the precision of different sample-based strategies. We compared the standard errors of estimators of area of forest loss and area of degradation obtained from simple random, stratified random and systematic sampling as applied to these population data. To construct strata for the stratified design, we evaluated two forest loss maps produced from Landsat data, a 30 m global forest loss product and a 30 m national forest loss map produced specifically for Guyana. For both of these maps, several options for defining stratum boundaries and allocating sample size to strata were evaluated. All stratified design options reduced the standard error of the area estimators relative to simple random sampling. The Dalenius-Hodges and Jenks methods for choosing stratum boundaries yielded greater improvements in precision than the Equal Area method. For this Guyana case study, optimal and equal allocation of sample size to strata led to substantially better precision than proportional allocation. Only small improvements in precision were attained by increasing the number of strata from three to five. For simple random sampling, incorporating the global and national forest loss map information in a regression estimator reduced standard errors of estimated area of forest loss and area of degradation relative to the standard error of the Horvitz-Thompson estimator that does not incorporate the forest loss map information. However, the best performing stratified sampling design options had better precision than the regression estimator. RapidEye data cost 800 USD per ‘3A’ tile so the annual imagery cost for mapping Guyana would be 274,000 USD. For an investment of 75,200 USD (the cost of 94 RapidEye tiles, the largest sample size evaluated), the best performing stratified random sample achieved a relative standard error (100% times the standard error divided by area) of 7% for estimating area of forest loss and 6% for estimating area of degradation. This study demonstrates the utility of Landsat-based forest loss maps to provide effective strata to improve precision of area estimators produced from a sample of RapidEye imagery in a country for which forest loss and degradation are very rare features of the landscape.

Land Change Modelling to Inform Strategic Decisions on Forest Cover and CO2 Emissions in Eastern Madagascar

SummaryDecision-makers need readily accessible tools to understand the potential impacts of alternative policies on forest cover and greenhouse gas (GHG) emissions and to develop effective policies to meet national and international targets for biodiversity conservation, sustainable development and climate change mitigation. Land change modelling can support policy decisions by demonstrating potential impacts of policies on future deforestation and GHG emissions. We modelled land change to explore the potential impacts of expert-informed scenarios on deforestation and GHG emissions, specifically CO2 emissions, in the Ankeniheny–Zahamena Corridor in eastern Madagascar. We considered four scenarios: business as usual; effective conservation of protected areas; investment in infrastructure; and agricultural intensification. Our results highlight that effective forest conservation could deliver substantial emissions reductions, while infrastructure development will likely cause forest loss in new areas. Agricultural intensification could prevent additional forest loss if it reduced the need to clear more land while improving food security. Our study demonstrates how available land change modelling tools and scenario analyses can inform land-use policies, helping countries reconcile economic development with forest conservation and climate change mitigation commitments.

Deforestation pattern dynamics in protected areas of the Brazilian Legal Amazon using remote sensing data

Forest fragmentation and deforestation are subjects of great concern in tropical regions, namely in South America and Africa, contributing to a rapid loss of tropical forest area and with serious implications for ecosystem functioning and biodiversity conservation. Despite the decrease in deforestation rates in recent years, the Brazilian Amazon, with the largest continuous region of tropical forest in the world, has suffered the greatest recorded losses, which have been contributing to continuous habitat fragmentation and a reduction in the territory occupied by Amerindian populations. In an attempt to preserve the remaining habitats and forests, Brazil has been adopting land conservation policies, including the implementation of protected areas. Protected areas (PAs) possess the potential to significantly reduce habitat fragmentation by conserving large, contiguous areas of land. In order to examine how effective PAs are at conserving forest area in the Brazilian Legal Amazon, patterns of deforestation are analyzed and compared, inside and outside the PAs, through landscape metrics calculated using the Patch Analyst and V-LATE extensions of a Geographic Information System. Two different sources (the Hansen Global Forest Change Dataset and the Brazilian National Institute for Space Research's (INPE) PRODES project) of annual forest cover-loss data derived from satellite imagery at medium-to-high spatial and temporal resolutions are compared at two-yearly intervals across 2002–2016. Additionally, fragmentation levels associated with deforestation patterns are assessed through an index modeled using a set of uncorrelated landscape metrics, and the associated change factors and trend are discussed. Results show that there is greater fragmentation in some PAs located in Mato Grosso and Pará States, especially those near the “arc of deforestation”, and that Yanomami Indigenous Lands (YIL) are tending towards more fragmentation. Although some PAs are in a critical condition, findings show they all actively contribute to improved conservation of the native ecosystem and, in conjunction with sustainable management policies, will continue to help reduce or avoid forest fragmentation and degradation processes.

Is the impact of loggings in the last primeval lowland forest in Europe underestimated? The conservation issues of Białowieża Forest

Loggings in biodiversity hot-spots are perceived as very serious threat to forest species and habitats of high conservation interest. In this paper we scrutinize the spatial impacts of recent loggings in the Polish part of the renowned Białowieża Forest being the last remaining area of lowland temperate forest with a primeval character in Europe with the status of World Heritage and Natura 2000 site. The loggings have been applied in order to cope with the outbreak of the spruce bark beetle Ips typographus. We used satellite images to perform cover change detection analysis that delineated areas being logged in Białowieża Forest between July 2015 and June 2018. Next, we assessed the extent of forest loss in areas with different management regimes as well as landscape-scale impacts. The total area of detected clear-cuts amounted to at least 675 ha, including 229 ha of old-growth stands. Assuming a buffer of 100 m from the edge of cleared forest patches, the cumulative direct and indirect impact of recent logging activities was estimated to amount to at least 4073 ha of affected forest. Logging activities resulted in a 26% increase in fragmentation in the entire Natura 2000 area. We argue that the ecological impact of logging extends beyond the logged areas by modifying the landscape structure and affecting ecosystem functioning on a landscape scale. As such, the recent salvage loggings in the Białowieża Forest clearly damaged the conservation value of this precious area, not in the least by increasing its fragmentation. To avoid further degradation, we strongly argue for allowing natural tree regeneration on clear cuts and also for the extension of Białowieża National Park to cover the entire forested area.

A systems approach to assess climate change mitigation options in landscapes of the United States forest sector

BackgroundUnited States forests can contribute to national strategies for greenhouse gas reductions. The objective of this work was to evaluate forest sector climate change mitigation scenarios from 2018 to 2050 by applying a systems-based approach that accounts for net emissions across four interdependent components: (1) forest ecosystem, (2) land-use change, (3) harvested wood products, and (4) substitution benefits from using wood products and bioenergy. We assessed a range of land management and harvested wood product scenarios for two case studies in the U.S: coastal South Carolina and Northern Wisconsin. We integrated forest inventory and remotely-sensed disturbance data within a modelling framework consisting of a growth-and-yield driven ecosystem carbon model; a harvested wood products model that estimates emissions from commodity production, use and post-consumer treatment; and displacement factors to estimate avoided fossil fuel emissions. We estimated biophysical mitigation potential by comparing net emissions from land management and harvested wood products scenarios with a baseline (‘business as usual’) scenario.ResultsBaseline scenario results showed that the strength of the ecosystem carbon sink has been decreasing in the two sites due to age-related productivity declines and deforestation. Mitigation activities have the potential to lessen or delay the further reduction in the carbon sink. Results of the mitigation analysis indicated that scenarios reducing net forest area loss were most effective in South Carolina, while extending harvest rotations and increasing longer-lived wood products were most effective in Wisconsin. Scenarios aimed at increasing bioenergy use either increased or reduced net emissions within the 32-year analysis timeframe.ConclusionsIt is critical to apply a systems approach to comprehensively assess net emissions from forest sector climate change mitigation scenarios. Although some scenarios produced a benefit by displacing emissions from fossil fuel energy or by substituting wood products for other materials, these benefits can be outweighed by increased carbon emissions in the forest or product systems. Maintaining forests as forests, extending rotations, and shifting commodities to longer-lived products had the strongest mitigation benefits over several decades. Carbon cycle impacts of bioenergy depend on timeframe, feedstocks, and alternative uses of biomass, and cannot be assumed carbon neutral.

Lower land-use emissions responsible for increased net land carbon sink during the slow warming period

The terrestrial carbon sink accelerated during 1998-2012, concurrently with the slow warming period, but the mechanisms behind this acceleration are unclear. Here we analyse recent changes in the net land carbon sink (NLS) and its driving factors, using atmospheric inversions and terrestrial carbon models. We show that the linear trend of NLS during 1998-2012 is about 0.17 +/- 0.05 Pg C yr(-2), which is three times larger than during 1980-1998 (0.05 +/- 0.05 Pg C yr(-2)). According to terrestrial carbon model simulations, the intensification of the NLS cannot be explained by CO2 fertilization or climate change alone. We therefore use a bookkeeping model to explore the contribution of changes in land-use emissions and find that decreasing land-use emissions are the dominant cause of the intensification of the NLS during the slow warming period. This reduction of land-use emissions is due to both decreased tropical forest area loss and increased afforestation in northern temperate regions. The estimate based on atmospheric inversions shows consistently reduced land-use emissions, whereas another bookkeeping model did not reproduce such changes, probably owing to missing the signal of reduced tropical deforestation. These results highlight the importance of better constraining emissions from land-use change to understand recent trends in land carbon sinks.

Forest cover loss and recovery in an East African remnant forest area: Understanding its context and drivers for conservation and sustainable ecosystem service provision

Understanding of the often complex forest cover change drivers, and the perceived and observed forest cover changes substantially contributes to the sustainable management of tropical forests. This paper aims at developing an integrated view on tropical forest cover change and its drivers by combining the perception of the stakeholders (farmers, forest guards, and forest managers) and five decades forest cover mapping, based on interview and remote sensing respectively, through a case study in the central highlands of Ethiopia. Afforestation and deforestation occurred when law enforcement was stronger and weaker respectively, depending on political regimes. Since 1937 i.e., the early Imperial period, the position of the forest edge has not changed much over time, it rather became sharper. In the late Imperial era (1972–1975), the forest cover declined only by 1.6%. In the subsequent two governments, the socialist and the current federal rule (1975–2014), the forest cover increased by 17%. There was a 3.9% forest cover decline during the transition between the two governments. This pattern of overall net forest cover increase observed by remote sensing data has been correctly perceived by stakeholders. Stakeholders acknowledged the observed forest cover increase, however, they argued that the forest is declining in terms of its quality for several ecosystem services (ES). The ES decline is believed to have resulted from the gradual shift of pure dense indigenous forest to an increasing share of exotic plantations. In the three political regimes, land policy, illegal encroachments, population pressure and social unrest have been the leading drivers of forest cover change. Communities' involvement in forest management activities and sharing benefits were regarded as positive perception of forest management strategies during the federal administration (1993–2007) of the current government by farmers. Among the factors that determine forest management strategies proposed by stakeholders are gender, landholding size, education level and age. Future conservation and development interventions need to consider stakeholders' concerns. Their involvement in forest management is also necessary for improved biodiversity conservation, ecosystem service provision, and social wellbeing.

Detecting Vegetation Change in Response to Confining Elephants in Forests Using MODIS Time-Series and BFAST

Afromontane forests are biodiversity hotspots and provide essential ecosystem services. However, they are under pressure as a result of an expanding human population and the impact of climate change. In many instances electric fencing has become a necessary management strategy to protect forest integrity and reduce human-wildlife conflict. The impact of confining hitherto migratory elephant populations within forests remains unknown, and monitoring largely inaccessible areas is challenging. We explore the application of remote sensing to monitor the impact of confinement, employing the Breaks For Additive Season and Trend (BFAST) time-series decomposition method over a 15-year period on Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) (MOD13Q1) datasets for two Kenyan forests. Results indicated that BFAST was able to identify disturbances from anthropogenic, fire and elephant damage. Sequential monitoring enabled the detection of gradual changes in the forest canopy, with degradation and regeneration being observed in both sites. Annual rates of forest loss in both areas were significantly lower than reported in other studies on Afromontane forests, suggesting that installing fences has reduced land-use conversion from human-related disturbances. Negative changes in EVI were predominantly gradual degradation rather than large-scale, abrupt clearings of the forest. Results presented here demonstrate that BFAST can be used to monitor biotic and abiotic drivers of change in Afromontane forests.

Ongoing primary forest loss in Brazil, Democratic Republic of the Congo, and Indonesia

Humid tropical forests provide numerous global ecosystem services, but are under continuing threat of clearing from economic drivers. Here, we report primary humid tropical forest extent for the year 2001, and primary forest loss and distance to loss from 2002–2014 for the largest rainforest countries of Brazil, Democratic Republic of the Congo (DRC), and Indonesia. Brazil’s total area of primary forest loss is more than twice that of Indonesia and five times that of DRC. Despite unprecedented success in slowing deforestation along its forest frontier, Brazil’s most remote forests are increasingly nearer to loss, as extractive activities such as logging and mining intrude upon previously intact forests. In absolute terms, DRC has the lowest area of primary forest loss; however, its forests are increasingly encroached upon as smallholder agriculturalists move into remaining forests, often to escape conflict and insecurity. The decrease in DRC forests’ distance to loss as a function of area of forest loss was five times that of Brazil or Indonesia. In 2014, Indonesia had the least area of remaining primary forest. Despite an announced moratorium on concession licenses in 2011, Indonesia exhibited a rate of primary forest loss twice that of DRC and triple that of Brazil by the end of the study period. Forest loss dynamics in Indonesia range from industrial-scale clearing of coastal peatlands to logging of interior montane rainforests. While results illustrate considerable variation in forest loss dynamics between the three countries, the dominant narrative is of ongoing exploitation of primary humid tropical forests.

Do Sustainable Forest Managements Affect Forest Conservation?

This study examined the effect of sustainable forest management schemes on forest conservation using remote sensing data on forest change. We applied fixed effect models focusing on two major sustainable forest management schemes: the Forest Stewardship Council and the Programme for the Endorsement of Forest Certification. The regression results showed that, contrary to findings from previous research, expansion of the sustainable forest management area was uncorrelated with forest loss when the fixed effects of country and time were controlled. Our findings were robust to different types of forest definition and to country groups restricted by OECD or non-OECD membership. Our estimations suggested that sustainable forest management increased forest loss in non-certified forest areas, indicating the existence of leakage of forest loss from certified to non-certified forest areas. These findings imply that leakage effects should be considered when implementing forest management or protected forest schemes.

Shadows of the edge effects for tropical emergent trees: the impact of lianas on the growth of Aspidosperma polyneuron

Forest edge impacts emergent trees growth by reducing the number of growth releases. This reduction seems to be related with lianas infestation found at the forest edge. Deforestation in tropical regions is raising fragmentation to alarming levels. Not only does it lead to losses of forest area, but also the abiotic and biotic changes on forest edge areas alter the development of the remaining trees. We aimed to assess the impacts of forest fragmentation on the growth of tropical emergent trees. We sampled the endangered species Aspidosperma polyneuron (Apocynaceae) at forest edge and interior in the highly fragmented Brazilian Atlantic Forest. We obtained increment cores of each tree along with data about tree and surrounding canopy heights, plus their current levels of liana infestation. We used tree-ring analyses to estimate age and growth rate of trees. Sampled trees and surrounding canopy were taller at the forest interior than at the edge, even though both sampled populations have similar ages. Overall, trees at forest interior show a lifetime growth pattern common to shade-tolerant species, with a peak of growth rate at 120 years. Indeed, all sampled trees exhibited this pattern before fragmentation. However, trees at forest edge presented constantly slow growth rates for all diameter classes after the fragmentation event. The strong presence of lianas at forest edge prevents trees from experiencing the expected growth releases throughout their lifetime, probably by keeping the leaves of A. polyneuron under shaded conditions. Therefore, the management of lianas at the forest edge is likely the most effective procedure to ensure the growth of emergent trees, guarantying their role on forests structure, carbon storage, and ecosystem functioning.

Emerging trends of tropical dry forests loss in North & Central America during 2001–2013: The role of contextual and underlying drivers

Historical anthropogenic pressures on tropical dry forests (TDF) have led to the loss of more than 50% of its potential coverage worldwide. However, information on the temporal and spatial dynamics of TDF deforestation or disturbance is scarce. In this study, we present a national and sub-national level assessment of TDF loss patterns in Mexico and Central America at high spatial and temporal resolution using remote sensing and GIS technologies. We used the Global Forest Change (GFC) dataset published by Hansen et al. (2013) which shows detected forest loss at 30-m pixel resolution at interannual rates from 2000 through 2013. We analyzed TDF loss within a peer reviewed moderate resolution map of TDF extent based on 2004 satellite imagery, eliminated potential sources of errors and enforced all polygons to correspond to forest loss only within TDF dominated cover. We analyzed trends in the magnitude of deforestation (total forest loss area) and TDF loss patch size as well as density of forest loss across the region. We also investigated the spatial pattern of increasing or decreasing temporal trends of forest loss by applying a space-time hotspot analysis. For the 2001–2013 period, we identified five areas where TDF loss was high and had the tendency to increase; while widespread low TDF loss with the tendency to decrease was found across most Central America countries and most of the Pacific coast of Mexico. Contextual and underlying causative factors vary, conforming to cultural and socioeconomic differences across the region, with rural migration, small-scale agricultural expansion, agricultural intensification, oil palm expansion and cattle ranching amongst the main causes of TDF conversion.

Long-Term Changes in Forest Cover in Central Veracruz, Mexico (1993–2014)

Deforestation and fragmentation are threats to the conservation of species and have consequences for ecosystem functions. The focus of this study was to elucidate forest cover change in the period of 1993 to 2014. Our study area is in the central region of Veracruz, Mexico. Land cover and land use classes for the Years 1993, 2000, and 2014 were derived from Landsat images applying supervised classification. Then, we quantified the net change in forest area, the loss of original forest area, and evaluated forest fragmentation using landscape metrics. Our results showed that the area covered by remnant forests decreased 57%. The annual net forest cover change rate for 1993 to 2000 was −0.44%; since then forest cover increased at a rate of 0.11% from 2000 to 2014. The decreasing total edge density and the mean proximity index during the entire period of the study indicate decreasing irregularity in the shape of remnant forest patches and a slight decrease of vulnerability to edge effects. Forest patches augmented in 2000 and decreased in 2014 demonstrating an 18% decrease in relation to the number of fragments existing in 1993. According to our study, this area demands an urgent attention on preservation initiatives because only 2% of the surface extent is below federal protection and 0.8% is under State protection. It is important to protect the larger forest areas left in the pine-oak and humid montane forest belt because of their importance to plant diversity conservation and particularly, as these are threatened by urban and agricultural expansion.

Assessment of the land surface temperature dynamics in the city of Sofia using Landsat satellite data

The paper presents the results of forest cover change mapping in two study areas in Bulgaria (in mountainous and plain-hilly terrain) for period of about 20 years. A comparison was made of two approaches for classification of multitemporal SPOT HRV/HRVIR data with 20 m spatial resolution. The first approach was the post-classification comparison, i.e. pixel-by-pixel comparison of forest/non forest maps produced by separate classifications of the images from the two ends of the time period. The second approach was a direct multitemporal classification of an image stack comprised of the two-date image data. Following international guidance, instead of counting pixels in the map to obtain the area of forest loss and gain, the areas were estimated by applying an unbiased estimator to sample data collected by stratified random sampling. The map was used to stratify the study areas. Producer’s, user’s and overall accuracy were also estimated using the sample data. A comparison of accuracy and area estimates, and confidence intervals of estimates, showed that the map produced by direct multitemporal classification was more accurate. It yielded consistently higher class-specific accuracies than the map made by post-classification comparison. As expected, the accuracies of the change classes – forest disturbance and reforestation – were significantly lower than that of the stable classes regardless of the change detection approach. Finally, practical issues and guidelines for future forest change detection studies were discussed.