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Abstract: In the modern era, high-impact mega-fires are unprecedented for the suppression costs, property losses, natural resource damages, and loss of life often involved. For a number of years, these extraordinary wildfires have been increasing in number and in severity. They affect countries around the world, including those with enormous firefighting capabilities. High-impact mega-fires are frustrating efforts to provide for public safety, slow rates of deforestation, sequester carbon and reduce black carbon emissions. Despite more determined bidding, attempts to match increasing wildfire threats with greater suppression force have not stemmed climbing mega-fire trends. Yet, the majority of after-action reviews, reports, and commissions continue to weight recommendations to correcting emergency response deficiencies, generally through a fire operations lens. This paper explores the mega-fire phenomenon through a forest land management prism. It is an early attempt to focus on the contributory factors that may set the stage for high-impact mega-fires. The paper draws on the results from two coarse-filter overviews of high-impact mega-fires from around the world and the authors’ firsthand experiences dealing with others in the United States. Drought and fire exclusion policies have been implicated in the large fire problem. However, several high-impact mega-fires can be further traced to land management decisions that resulted in dense forest conditions with high biomass and fuel build-ups over extensive areas. As droughts have intensified, more of these accumulated fuels have become available to burn at intensities that exceed suppression capabilities. In contrast, some places have managed to largely avoid high-impact mega-fires. State and federal lands in Florida and Crown lands in Western Australia have better aligned policies and practices with the disturbance regimes that define the forested landscapes that they protect. They use prescribed fire at appropriate intensities, intervals, and scales to reduce fuels as the means to protect people, maintain forest resilience, ensure biodiversity, and increase margins of suppression effectiveness. Forest land management policies and practices that, by design or by default, result in greater volumes of fuel and rely on suppression capabilities to maintain these conditions may no longer be sustainable as droughts deepen and become more widespread. This paper suggests that adapting wildland fire management programs, forest land management policies, and the current regulatory framework to the reality of warmer, drier climate patterns will be essential in reducing mega-fire risks. Protecting fire-prone landscapes can no longer rely on suppression alone; protection will become more dependent on the management of forests where high-impact mega-fires incubate. [Copyright &y& Elsevier]

Highlights • In 2016, field hedges extend over 5.6 km per km2 of cropland in Dantiandou district, Niger. • On average there is one woody plant growing every 5 to 6 m along a field hedge. • No overall trend in woody plants of 12 sampled field hedges observed over 24 years. • The field hedge network expanded by 3.7% annually following land tenure splitting. • Woody plants of field hedges contribute to increase woody plants in croplands. Abstract Changing woody plant density across agricultural landscapes of the Sudano-Sahelian region is a debated issue. This paper reports the results of an investigation on the contribution of field hedges to overall woody plant density. Hedges separating individual cropped parcels were studied within village agropastoral territories in the Dantiandou district in western Niger. In 1992, field hedges were mapped over the study area using aerial photography and in 2016, using high resolution Google Earth imagery. In 1992, field hedge length was equal to 1006 km within 435 km2 of croplands, equivalent to 2.3 km km−2. In 2016, 17.5% of these hedges had disappeared, but 1591 km of new hedges were observed resulting in an increased density of hedges to 5.6 km km−2. In 24 years, hedges had increased at a mean annual rate of 3.7% likely associated with the splitting of crop fields by inheritance. The composition and productivity of hedges were also monitored in 1996, 2010 and 2015. All trees (maximum height ≥ 4 m), shrubs (<4 m) and tussock perennial grasses were recorded within twelve field hedge samples of 200 m each. Field measurements were used to estimate basal area, crown area, foliage mass and wood mass of each woody plant within the sampled hedges. No significant trends were found between 1996 and 2015 in woody plant density, basal area, crown cover, wood and foliage masses across all monitored hedges. However, overall means hide a slight decrease in tree contributions, while shrub contributions first increased and then decreased. They also mask contradictory trends among sites most likely related to different rates of shrub coppicing and tree cutting. The woody species composition of the hedges is poor with an increase of Combretum glutinosum to the detriment of Guiera senegalensis over the study period. Multiplying the hedge sample statistics by the changing lengths of field hedges in the study area provides estimates of the contribution of the hedge woody plants to the woody plant population at a landscape scale. Between 1992 and 2016, field hedges contributed to increases of woody plant density by 3.9%, basal areas by 5.4%, crown cover by 2.7%, leading to 6.1% annual increase in foliage mass and 8.8% increase in wood mass. [ABSTRACT FROM AUTHOR]

• The Atlantic Forest is the biome with the highest number of papers on ecological restoration. • Pantanal, Pampa and Caatinga are the least studied in terms of ecological restoration. • In all biomes, most of the studies are related to monitoring. • The number of species used in restored areas is limited. • It is necessary to include different life forms, restoration techniques and studies using reference areas to measure success. The Bonn challenge aims at the restoration of 350 million hectares of degraded ladscapes by 2030. In Brazil, the restoration goal for 2030 is 12 million hectares. Despite the great demand for ecological restoration across the whole of Brazil, there have been no analyses of the studies carried out in different biomes. In addition, conservation efforts must cover all biomes, so that different regions can take advantage of the many benefits of restoration. Our aim was to identify advances and gaps in current restoration knowledge in order to guide future efforts in Brazil. Our bibliometric survey in the Web of Science using 23 keywords related to restoration generated a total of 530 papers, of which 291 were included in the analysis. The papers were published in 121 scientific journals between 1988 and 2018, with the largest number of papers in 2016. The Atlantic Forest was the biome with the highest number of studies, as it is one of the most threatened tropical forest regions in the world and maintains the largest number of research institutions and receives the highest level of funding support in the country. Regarding the types of studies, temporal monitoring was more frequent in the Amazon, Cerrado, Caatinga, and Pampa, while the monitoring at one point in time was more frequent in the Atlantic Forest. From the studies examined, 31% used a reference area for comparing restoration success. The most studied organisms were plants (81%), and among them, trees were the most frequent, followed by fungi, birds, invertebrates, mammals, and reptiles. The pre-restoration degradation differed among biomes, with deforestation for logging the most cited in the Amazon, agriculture, and livestock in the Atlantic Forest and Cerrado, logging and cattle ranching in Caatinga, and livestock in the Pampa and Pantanal. In general, active/assisted natural succession was the most frequent restoration process: planting seedlings more readily occurred in the Amazon, Atlantic Forest, and Caatinga, whereas natural regeneration in the Cerrado and Pantanal and sowing in Pampa. The studies varied among the age of restoration (>1 to 67 years for active restoration and >1 to 120 years for passive/unassisted natural succession), and the number of species planted (1 to 121 species). We identified an important regional knowledge gap for the Pantanal, Caatinga, and Pampa, as well as the need to include reference areas, evaluate different restoration techniques (besides planting seedlings), and the inclusion of other taxa and life forms in biodiversity studies apart from trees. We also identified the need to expand research to assess landscape metrics, prioritization, legislation, and public policies. [ABSTRACT FROM AUTHOR]

The impact of agricultural and livestock activities on tropical forests often results in long-lasting damage to soil and vegetation. In undisturbed tropical forests, nutrient stocks tend to be larger in the aboveground biomass than in the soil profile; therefore, deforested sites may remain bare for decades due to nutrient limitation. In such circumstance, amelioration of edaphic conditions and planting of tree species adapted to open canopy conditions (pioneers) could help restore ecosystem functions while providing a sustainable source of timber and prompting natural succession. The aim of this study was to evaluate the use of biochar as a soil amendment that could accelerate the reforestation of degraded lands. We used a randomized block design with five treatments and four replications, comparing the performance of exotic eucalyptus ( Eucalyptus urophylla × Eucalyptus grandis ) and native Tachigali vulgaris trees. We monitored reforested plots for 49 months, evaluating tree survival and growth rates, litter production, canopy cover and density of invasive grasses. The addition of biochar in the soil did not result in significant differences in tree survival or productivity when compared to controls. Comparing the two species, native trees ( T. vulgaris ) performed better by all metrics, showing 52% survival and producing 241.7 Mg ha −1 of aboveground biomass after four years of growth. During that same period the survival rate of eucalyptus was 38% and the aboveground productivity was only 82.4 Mg ha −1 . In contrast with eucalyptus plantations, T. vulgaris showed rapid canopy cover and completely suppressed invasive grasses, generating up to 11.7 Mg ha −1 more litter than eucalyptus trees. Although eucalyptus is one of the most commonly used species in reforestation for timber, charcoal, and pulp and paper production in Brazil, our results demonstrate that T. vulgaris has the potential to replace eucalyptus in commercial plantations with the added benefit of being a native species that can promote the establishment of a stable forest cover in degraded sites. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

Abstract: Understanding actor-specific responsibility for deforestation in the Brazilian Amazon is key in adjusting policy and resource allocation in the face of current forest destruction. However, previous research shows that there is great variability in such assessments. To contribute to the ongoing discussions on forest conservation and rural development policies in the Amazon, this paper studies actor-specific deforestation and its environmental effects in four municipalities situated along the Transamazon Highway. We used spatially explicit methods that integrate a database of 8281 georeferenced properties with a time series of remote-sensing data covering four periods between 1986 and 2007. We also included landscape ecology metrics as improved indicators of the complex environmental effects of forest fragmentation. The analysis demonstrates that smallholders (defined as colonists who own less than 100ha of land) were responsible for 23% of total deforestation in the study region while accounting for 55% of the total properties. We also explored the relationship between property size and deforestation at the property level, finding that it closely follows a power distribution. Property deforestation increased with property size, while the percentage of property deforestation decreased. In spite of this, compliance with current legal requirements to maintain 50% of property forest cover was not statistically different between smallholders and largeholders. In comparison to municipalities dominated by medium- and large-scale ranchers, the smallholder-dominated municipality of Medicilândia showed better performance in all applied landscape metrics with well-established relationships with the provision of important environmental goods and services. Although all studied municipalities showed severe accumulated deforestation, Medicilândia experienced an abrupt decrease in municipal deforestation after 1999 to just 0.03%year−1, while municipalities dominated by larger holders maintained or increased their previous deforestation rates to between 0.90% and 1.34%year−1 in the same period. This indicates that the smallholders’ productions schemes in our study area might present potential for agricultural frontier stabilization based on improved land-use efficiency. The policy implications of our findings are discussed, especially with regard to the role of smallholders in productive forest conservation. [Copyright &y& Elsevier]

Abstract: On the south shore of the western Mediterranean Basin, mountain forest ecosystems are degraded, mainly due to their overexploitation. Topographic, edaphic and climatic conditions create stressful growing conditions and sensitive ecosystems. Nonetheless, in these ecosystems, forests remain an important resource for the subsistence of local populations. Historically the vulnerability of this resource has prompted mankind to establish traditional control forms of forest and pastoral areas. These common resource management systems are still functioning in the Moroccan High Atlas Mountains under the name of agdal which refers to the territory, the resources and access rules laid down by the local population in order to manage the territory. The estimation of land cover changes was a suitable method to evaluate the effectiveness of these community-based systems for forest conservation. In this paper we highlight the impact of this traditional management on woodland dynamics in a mountainous area (Aït Bouguemez Valley) through the use of remote sensing approaches, associated with forest structure characterisation and the analysis of social mechanisms. A diachronic analysis based on the comparison of aerial photographs (dated 1964) with a recent Spot 5 satellite image (from 2002, 2.5m resolution) was performed. Estimation of changes in canopy cover percentage was achieved using a graphic chart as a base for the photo-interpretation, and a subsequent validation by field sampling. A map of canopy cover changes between 1964 and 2002 was produced. Ecological measurements of trees were also achieved on field plots. The results indicate that in the past 38 years, forest ecosystems have been affected by a relative decrease of 20.7% of the total forest area, and 8.7% for the mean canopy cover percentage. However, strong disparities in forest dynamics arose according to the agdal or non-agdal status of the forest. Significant progression in canopy cover is noted in controlled agdal areas but large degradation has occurred outside. Regarding the stand ecological conditions, we observed significant differences in the stand structure, according to the management mode. We suggest through this study increased recognition of customary forest regulations, which may be adapted and extrapolated to other communities. However, from an ecological point of view, the agdal system alone is not sufficient to reach a viable management mode in the long term. [Copyright &y& Elsevier]

Abstract: Estimates of greenhouse-gas emissions from deforestation are highly uncertain because of high variability in key parameters and because of the limited number of studies providing field measurements of these parameters. One such parameter is burning efficiency, which determines how much of the original forest''s aboveground carbon stock will be released in the burn, as well as how much will later be released by decay and how much will remain as charcoal. In this paper we examined the fate of biomass from a semideciduous tropical forest in the “arc of deforestation,” where clearing activity is concentrated along the southern edge of the Amazon forest. We estimated carbon content, charcoal formation and burning efficiency by direct measurements (cutting and weighing) and by line-intersect sampling (LIS) done along the axis of each plot before and after burning of felled vegetation. The total aboveground dry biomass found here (219.3Mgha−1) is lower than the values found in studies that have been done in other parts of the Amazon region. Values for burning efficiency (65%) and charcoal formation (6.0%, or 5.98MgCha−1) were much higher than those found in past studies in tropical areas. The percentage of trunk biomass lost in burning (49%) was substantially higher than has been found in previous studies. This difference may be explained by the concentration of more stems in the smaller diameter classes and the low humidity of the fuel (the dry season was unusually long in 2007, the year of the burn). This study provides the first measurements of forest burning parameters for a group of forest types that is now undergoing rapid deforestation. The burning parameters estimated here indicate substantially higher burning efficiency than has been found in other Amazonian forest types. Quantification of burning efficiency is critical to estimates of trace-gas emissions from deforestation. [Copyright &y& Elsevier]

Abstract: In the Andes, demand for water is growing and upland land-use changes are increasing. Water quality, quantity and seasonal flow have thus also become environmental services with potential monetary value. Yet, currently the region''s pioneer PES schemes are not paying for measured environmental services, but for proxy land uses thought to provide the(se) service(s). Hydrological modeling makes explicit the tacit causal relationships and tests underlying assumptions. Ideally, when combined with an economic analysis of land-use alternatives, this could inform decision makers on how much to pay for different interventions in different spatial locations. This paper focuses on two Andean watersheds: Moyobamba (Peru) and Pimampiro (Ecuador). In the first case, a municipal water company is preparing a payment for environmental services (PES) scheme to reduce upstream sediment loads. In the second, a similar conservation-oriented municipal PES scheme has operated since 2000, but the hydrological linkages have never been tested. Applying the Soil & Water Assessment Tool (SWAT), we identify in both watersheds biophysically critical areas for service delivery, and compare services for current land uses with change scenarios: deforestation, reforestation, live barriers, and agroforestry. We then use the ECOSAUT optimization model to predict net economic benefits for service providers. In Moyobamba, switching to shade-grown coffee would halve sediment yields, and increase significantly farmers’ economic benefits. This requires high up-front investment, but the willingness to pay of water users in Moyobamba town may suffice to cover the upfront costs. In Pimampiro, resumed deforestation would increase sediments by >50% and reduce dry-season flow by 0.5%, thus reinforcing the rationale of the existing PES scheme, focused on conserving native forests and grasslands. [Copyright &y& Elsevier]

Abstract: The ecological consequences of climate change for large tropical forests such as the Amazon are likely to be profound. Amazonian forests strongly influence regional and global climates and therefore any changes in forest structure, such as deforestation or die-back, may create positive feedback on externally forced climate change. Monitoring, modelling and managing the impacts of anthropogenic climate change on forest dynamics is therefore an important objective of forest researchers, and one that requires long-term data on changes at the level of community, populations and phenotypes. In this paper we provide the most comprehensive study yet on the seasonal dynamics of various leaf traits: leaf area index (LAI), leaf mortality (LM), leaf biomass (LB), leaf growth rate (LG), and leaf residence time (TR) from 50 experimental plots in a forest site at Belterra, Pará State, Brazil. From this study we estimate annual mean leaf area index (LAI) to be 5.07m2 m−2 and annual mean leaf dry biomass to be 0.621kgm−2. The typical leaf grew at 0.049kgm−2 month−1 and remained on the tree for 12.7 months. We compare these results to other similar studies and critically discuss the factors driving leaf demographics in Amazonia. [Copyright &y& Elsevier]

Abstract: Traditionally Land Use Cover Change (LUCC) studies have focused on processes of negative land-cover change, primarily deforestation, partially because examples of positive land-cover change were not common. During the last two decades an outstanding tropical dry forest restoration process had taken place in the province of Guanacaste, Costa Rica, which has given us a unique opportunity to study how and why tropical dry forest regrowth occurs. The purpose of this paper is to undertake a retrospective analysis of the social dynamics of forest deforestation and restoration in Guanacaste from 1960 to 2005. Hence we investigate how structural drivers shape patterns of forest-cover change and examine how the role that Costa Rica''s conservation policies had played in promoting forest restoration. Our study combined analyses of socioeconomic data and satellite images of forest cover. We showed that forest regrowth observed in Guanacaste after the 1980s was the result of multiple socioeconomic factors. Our results indicate that the degree of incentive provided by conservation policies such as Payment for Environmental Services are not enough to ensure that Guanacaste''s forest will be protected against the potentially negative impacts of future socioeconomic changes. The findings from our analysis can assist decision-makers and managers in other regions to understand how social, economic and political dynamics impact the effectiveness of forest conservation efforts. [Copyright &y& Elsevier]

Abstract: Tropical deforestation and habitat fragmentation in areas around conservation areas have been an important element for discussion in the conservation and policy-making community. In this paper, we evaluate land cover change processes around one of the most important tropical dry forest reserves in the Americas: the Chamela-Cuixmala Biosphere Reserve, Mexico. The analysis is conducted at three scales: regional scale (coast of the State of Jalisco), proximity to the reserve (via a 30-km buffer zone analysis), and inside the Biosphere Reserve. The proximity analysis is complemented by a unique data set that represents the extent and boundaries of Ejidos (local land management units) in the region. Results indicate that areas surrounding the reserve have low deforestation, with Ejidos and buffer areas having more forest cover as they get closer to the reserve. The nature of this important phenomenon is discussed in the context of the socio-economic conditions of the local communities. Our work suggests that the creation of a network of “Ejidos’ Conservation Areas”, in the context of an approach that will recognize payments for environmental services provided to local communities, could contribute to the conservation and maintenance of the rich biodiversity in a region that has one of the highest levels of endemism in the world. [Copyright &y& Elsevier]

Abstract: This paper reports on the net carbon flux caused by deforestation and afforestation in India over the period from 1982 to 2002, separately for two time periods, 1982–1992 (PI) and 1992–2002 (PII), using the IPCC 2006 guidelines for greenhouse gas inventories. The approach accounts for forest and soil C pool changes for (a) forest areas remaining as forests, (b) afforested areas and (c) deforested areas. The data set used were remote sensing based forest cover for three time periods (1982, 1992, 2002), biomass increments, biomass expansion factors and wood density. In addition a number of required coefficients and parameters from published literature were adopted. In the 1982–2002 period, the forest cover changed from 64.20Mha in 1982 to 63.96 and 67.83Mha in 1992 and 2002 respectively. During the PI and PII periods, plantations were also established of 0.2 and 0.5Mhayr−1, while the annual deforestation rate was about 0.22 and 0.07Mha in these periods, respectively. The average net flux of carbon attributable to land use change decreased from a source level of 5.65TgCyr−1 (or 0.09MgCha−1 yr−1) during PI (1982–1992) to a sink level of 1.09TgCyr−1 (or 0.02MgCha−1 yr−1) during PII (1992–2002). Over recent years, Indian forests have acted as a small carbon sink. The results indicate that the conversion of land to forest (regeneration/afforestation) led to a net uptake of 0.86 and 1.85TgCyr−1 in PI and PII, respectively. By contrast, the net C emissions from the forest land conversion to another land use (deforestation) resulted in annual emissions of 9.9 and 3.2TgC during PI and PII, respectively. The cumulative net carbon flux from Indian forests due to land use change between 1982 and 2002 was estimated as 45.9TgC. The largest fluxes result from the conversion of forest land to cropland and waste lands, and since there are uncertainties in input variables (due to very large spatial heterogeneity) that affect net C flux from land use change, there is an urgent need for more reliable district-based data to facilitate accurate and refined estimates in future. This study was intended to improve consistency and completeness in the estimation and reporting of greenhouse gas emissions and removals. [Copyright &y& Elsevier]

Abstract: Kakamega Forest is the last remaining rainforest in Kenya and the easternmost remnant of the Guinean-Congolian rainforest belt. As such, it is home to a large number of endemic fauna and flora species. Yet the remaining natural forest is under imminent threat of degradation due to a rapidly growing population in its vicinity and a poverty rate far above the national average. The growing demand for forest resources and ecosystem services will continue to exert great pressure on the remaining forest fragments. In this paper, we predict future hotspots of forest clearing of the remaining natural and old-growth secondary forest in Kakamega Forest. We parameterized an artificial neural network model using resilient backpropagation to simulate the likelihood of forest clearing for each location. Input variables into the network included historic information on forest clearings together with variables capturing the status of forest protection, accessibility to roads and markets, as well as topography and forest density. Simulation results were used to predict future clearings based on observed rates of change. Hotspots of forest clearing were derived by assessing the neighborhood density of predicted clearings. Our results indicate that forest clearings occurred across all forest fragments. Hotspots of future forest clearing tended to occur near roads and market centers. Most future hotspots were found in areas with a lower protection status, where some forest use is allowed. But our model also predicted considerable pressure on remaining old-growth forest resources in the strictly protected National Reserve. Our predictions of deforestation hotspots contribute to a better geographic targeting of nature protection activities and forest management investments in Kakamega Forest. Thus, it will hopefully help policy makers and land managers to strike a balance between satisfying the needs of local livelihoods and preserving the unique ecological values of Kakamega Forest for future generations. [Copyright &y& Elsevier]

Abstract: This paper estimates the difference in stand biomass due to shorter and lighter trees in southwest (SW) and southern Amazonia (SA) compared to trees in dense forests in central Amazonia (CA). Forest biomass values used to estimate carbon emissions from deforestation throughout, Brazilian Amazonia will be affected by any differences between CA forests and those in the “arc of deforestation” where clearing activity is concentrated along the southern edge of the Amazon forest. At 12 sites (in the Brazilian states of Amazonas, Acre, Mato Grosso and Pará) 763 trees were felled and measurements were made of total height and of stem diameter. In CA dense forest, trees are taller at any given diameter than those in SW bamboo-dominated open, SW bamboo-free dense forest and SA open forests. Compared to CA, the three forest types in the arc of deforestation occur on more fertile soils, experience a longer dry season and/or are disturbed by climbing bamboos that cause frequent crown damage. Observed relationships between diameter and height were consistent with the argument that allometric scaling exponents vary in forests on different substrates or with different levels of natural disturbance. Using biomass equations based only on diameter, the reductions in stand biomass due to shorter tree height alone were 11.0, 6.2 and 3.6%, respectively, in the three forest types in the arc of deforestation. A prior study had shown these forest types to have less dense wood than CA dense forest. When tree height and wood density effects were considered jointly, total downward corrections to estimates of stand biomass were 39, 22 and 16%, respectively. Downward corrections to biomass in these forests were 76Mgha−1 (∼21.5Mgha−1 from the height effect alone), 65Mgha−1 (18.5Mgha−1 from height), and 45Mg.ha−1 (10.3Mgha−1 from height). Hence, biomass stock and carbon emissions are overestimated when allometric relationships from dense forest are applied to SW or SA forest types. Biomass and emissions estimates in Brazil''s National Communication under the United Nations Framework Convention on Climate Change require downward corrections for both wood density and tree height. [Copyright &y& Elsevier]

Abstract: Central Rondônia is one of the most deforested regions in the Brazilian Amazon and contains areas at different stages of degradation forming a gradient from mature forest to highly urbanized and built-up areas. Regional data from satellite imagery are available from the 1980s, but apart from studies that quantify deforestation, the broad-scale landscape dynamics of Rondônia have not been examined well. This paper assesses the landscape changes between 1984 and 2002 in a watershed located in the central region of the state of Rondônia, Brazil, which has undergone systematic and rapid deforestation due to introduction of pasture that began in the 1970s. Bi-annual Landsat TM/ETM+ images from 1984 to 2002 were classified into three broad land cover types: mature forest, secondary forest, and pasture, resulting in a time series of land-use/land-cover maps. Landscape changes were evaluated by computing a cross tabulation between years, transition rates, and landscape metrics related to size, density, connectivity, configuration, and deforested patches distribution related to patch size and spatial proximity to roads and old pastures. Transition probability functions were fitted to the temporal series to predict land-use changes for the next 10 years, for three different scenarios: (1) continued land-use change; (2) eliminating clear-cutting and selective logging; and (3) eliminating clear-cutting, selective logging, and secondary vegetation clearing. Current land-use transitions cannot be sustained beyond the next 10–15 years. A more sustainable scenario for the region requires a major reduction of deforestation activities, implementing the “permanent preservation area” policy along riversides, and controlling land-use transitions at balanced levels. We recommend that forest managers in regions facing similar deforestation pressures should strive to maintain at least 35% mature or primary forest, because landscape fragmentation proceeds rapidly below this critical threshold. [Copyright &y& Elsevier]

Research per se is a highly heterogeneous activity with a variety of objectives, actors and stakeholders, and a range of mechanisms to enhance collaboration while minimizing cost and unnecessary duplication. There is an urgent need to disseminate the results of research in forms that can be understood by policy-makers, administrators, the media and the public as well as by resource managers and peer scientists.To be effective, research itself needs to be restored. It must be both proactive and reactive to policy and public issues and use modern techniques of information technology and networking. Current human demands on forests for social, environmental and economic benefits require new, interdisciplinary approaches to research and rapid implementation of relevant results by appropriate stakeholders.In this paper, the extents, rates and causes of deforestation are identified together with the criteria and indicators of sustainable forest management that have specific relevance to restoration of site productivity. The changes in forest policies and management objectives over the second half of the 20th century are described and it is recognized that the role of forests as global resources may conflict with national sovereignty. [Copyright &y& Elsevier]

This paper provides a brief background to Mongolia’s forest condition in 1994. Over recent years, since the introduction of a market economy and decentralization, there has been a rapid change in the forest sector. In 1994, the total designated forest area of Mongolia was 17.5 million ha, including 12.7 million ha of closed forest or 8.1% of the total land area. The forests are subdivided into (i) special forests; (ii) protection forests; (iii) industrial forests, based on their basic functions. The main causes of deforestation in Mongolia are (i) increasing livestock numbers; (ii) increasing demand for fuel and industrial wood; (iii) the impact of forest fires. Grazing and browsing in forest areas are most destructive to plantations and tree growth, causing deformities and stunting growth. Livestock breeding without adequate management system has major negative impacts on remnant forest growth. According to some statistics, the forest area has decreased by 1.2 million ha over the last 20 years. At present, production and supply of sawn timber boards for the domestic market is carried out without any regard to the actual quantity required. Major wood-based products in Mongolia are railway sleepers, windows and doors, wooden boxes for packing and school and office furniture. Products are also made for the frames of the traditional Mongolian “Ger” and specialized furniture for the interior. By 1996, Mongolia’s forest industry had total sales of US$ 2.1 million, which was 13% more than the previous year.Between 1992 and 1995, the incidence of fires in forest areas increased because a sharp rise in the number of people using the forest and steppe areas to cut trees, pick berries and nuts, collect firewood and deer horns, and to hunt. Mismanagement and negligence of the relevant authorities also contributed to this situation. It is necessary to take strong measures in order to identify the social and economic causes of fire outbreaks. Since 1970, forestry and timber harvesting companies have begun to harvest wild seeds, breed seedlings and conduct reforestation activities. Between 1980 and 1990, on nationwide level, over 20 million standard seedlings were planted in over 40 permanent nurseries to supply the reforestation work. At that time the scope of reforestation expanded. The total area planted over some 30 years has been very small compared to the deforestation. Even if just the area harvested during that period is considered, the reforestation rate is still lower than 15%. [Copyright &y& Elsevier]

• African ebony, traded since antiquity, is the only true ebony still traded globally. • Deforestation and bushmeat hunting pose long term threats to African ebony. • Exports from Cameroon have increased recently and China has become a major importer. • Logging in Cameroon is managed in response to demand rather than current stocks. • Examination of the interface between trade and ecology is crucial to its conservation. The Central African forest ebony, Diospyros crassiflora Hiern, is a small tree native to the moist forests of the Congo Basin. Its appealing black heartwood was one of the first products to be exported from the Gulf of Guinea in the 17th century and is today one of the main sources of ebony globally. Like for other ebony species, its commercial exploitation raises serious questions about the long-term sustainability of its trade and the viability of its populations, but the dots are yet to be joined. An examination of the interface between biology, trade, and ecology is crucial to identify the interrelated factors that could influence the potential success of its conservation. This paper reviews scientific and grey literature, forest inventories, herbarium and trade data to provide a critical assessment of the main threats to D. crassiflora populations and gaps in the current state of knowledge. It is shown here that the species is widespread but never abundant. In the longer term the species is threatened by forest conversion to agriculture and widespread hunting of large mammals on which the species rely for seed dispersal. It is currently selectively logged principally to make musical instruments and for the hongmu Chinese market, for which only one alternative black wood, the near-threatened Dalbergia melanoxylon Guill. et Perr., is commercially available. Trade statistics suggest that exports from source countries where the species is cut under the forest concession system are relatively low compared to countries like Cameroon which has seen a recent increase in exports, and where ebony is exploited without forest management plans. Logging remains a concern where the exploitation and trade of D. crassiflora are managed in response to demand rather than informed by current stock levels, growth rate and the particular reproductive biology of this species. The recent successes of private sector initiatives to ensure the long-term supply of ebony in Cameroon are promising, but would require long-term and large-scale commitments involving direct and indirect stakeholders to develop programs for the plantation and policies for the sustainable management of the species. [ABSTRACT FROM AUTHOR]

Cartographic modeling was used to examine the influence of deforestation on landscape pattern metrics. Progressive deforestation resultedin an increase in the spatial heterogeneity, fragmentation, and edgecharacteristics of a landscape while connectivity attributes varied with deforestation stage. Pattern changes in heterogeneity and edge characteristics were curvilinear, with metrics changing direction at the half-way point of deforestation. The progressive loss of forest enhanced edge length, interspersion, and convexity. There was an exponential decline in interior forest and mean patch size, while patch density and interpatch distance increased. The variability displayed by several pattern metrics reflect unpredictability in patch disappearance. The relative contribution of each metric for discriminating between contiguous and fragmented landscape conditions was ranked using discriminant analysis. The results suggested that the mastery of landscape analysis can be directly linked to the choice of the pattern metric. Percent forest interior, contiguity, and convexity were highly significant (P<0.001). Forest loss was also significantly reflected by mean patch size, number of patches, mean patch density, and interpatch distance. Metrics that contributed little to discrimination displayed unpredictable behavior or exhibited high variability among their mean values. This paper develops an approach for monitoring the influence of deforestation on the landscape, and examines how pattern-related habitat components are affected by deforestation. The ability to quantify pattern change resulting from deforestation has direct implications to resource management and wildlife habitat assessment. Descriptions of pattern chine accompanying deforestation provide a criticalcomponent of habitat analyses. (c) 1999 Elsevier Science B.V. [ABSTRACT FROM AUTHOR]

This paper presents a mangrove vegetation assessment from 1970 to 1993 of the Santiago River Mouth. Nayarit, West of Mexico. The aims of this work are to describe the plant composition and structure of mangrove in the study area, and to evaluate the deforestation level and its amplitude by means of a retrospective analysis of the cover and distribution area of mangrove species using a LandsatTM image, aerial photographs and oblique video. Mangrove of the study area is dominatedby Laguncularia racemosa with the average importance value of 158.18and 400 ha of plant cover, followed by Avicennia germinans, with an average importance value of 138.52 and 324 ha of plant cover. Mangrove showed seven height and five diametrical classes that include the two dominant species. L. racemosa was the dominant species in six of the eight compass lines. The highest absolute frequencies for both dominant species were found in the second height class frequency, and the first diametric class frequency. Cover area and distribution of mangrove in the study area were mapped using a LandsatTM5 image (April 1993). A supervised classification was applied using the maximum likelihood algorithm, considering ten initial classes. This classificationwas evaluated by obtaining a classification error matrix and by assessing its accuracy. The mangrove vegetation area reported before, considering the same area for image analysis, resulted to be overestimated in 56% regarding the value obtained in our photointerpretation (1065 ha). From the latter mangrove area, the current cover is 724 ha, which represents a decrease of 32% in a 23-yr period. ) 1998 Elsevier Science B.V. [ABSTRACT FROM AUTHOR]