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The determination of changes in soil organic carbon (SOC) content under different cropping systems is necessary for policy development oriented towards soil conservation, C sequestration, and future C credit markets. The aim of this study was to generate an open SOC dataset resulting from a systematic literature search related to the agricultural systems for Southeast Asia. The dataset has 209 articles and 4341 observations on soils of cropping systems in this region from articles published between 1987 and 2023. This dataset included different management practices, land uses, soil sampling depth, and length of SOC content assessment. In addition, inherent features of crop production reported in the experiments were included in the dataset. This dataset can be applied to quantify and compare the impact of different land uses or management practices on SOC content, providing foundational knowledge towards identifying sustainable practices. Lastly, it is a useful guide for future regional SOC sequestration policies and the development of C credit markets.

This paper introduces a dataset of aerial imagery captured during the 2022 cocoa growing season in the central-western region of Côte d'Ivoire. The images were acquired using a multispectral camera mounted on a DJI Phantom 4 unmanned aerial vehicle (UAV). The agricultural land surveyed encompasses 10 different types of cocoa-based agroforestry systems, each ranging from 2.6ha to 8.3ha, totaling 7638 images and covering 30ha. The UAV mission was conducted at an altitude of 80 meters, with a side overlap of 70% and a front overlap of 80%. This configuration achieved ground sampling distances (GSD) ranging from 4.2 to 4.6 cm providing high-resolution detailed imagery of those lands. These high-resolution RGB and multispectral images can be used to characterize the structural complexity of the systems as well as the abundance, and the health of the trees in these cocoa-based systems. It can be a valuable resource for researchers in the fields of ecology, agriculture, and environmental monitoring. The dataset supports a wide range of applications, from precision agriculture to sustainable cocoa land use management, making it a pivotal tool for enhancing agricultural practices and ecosystem management in Ivorian regions facing environmental and economic challenges.

This paper presents the results of a study using participatory mapping to collectively understand deforestation dynamics in Murehwa, a communal area approximately 90 km northeast of Harare, Zimbabwe's capital city. The study engaged smallholder farmers in a deliberative process through participatory mapping exercises in 15 villages. For each exercise, participants collaboratively drew two maps of their village, one for 1990 and another for 2021. They depict village boundaries, land uses and the magnitude of change between the two dates. Participatory mapping served as a platform for collective thinking, with the resulting maps used to facilitate discussions. They involved comparing land use between the two maps and identifying the drivers of the observed changes. Thematic approach was used to analyse the discussions in order to come up with collectively identified drivers of land use changes. The findings show that deforestation and resulting land use changes are primarily rooted in economic depression, selling of wood, tobacco farming, veld fires, unauthorised wood exploitation, illegal selling of land, increase in gardening, agricultural expansion and population growth. These results lay a foundational step towards the co-construction of a governance framework for practising agriculture in forest-adjacent areas. Moreover, the paper shares methodological reflections and experiences intended to promote initiatives where the construction of a shared understanding facilitates sustainable land-use practices that foster natural resource conservation.

Tropical forest degradation from selective logging, fire and edge effects is a major driver of carbon and biodiversity loss1,2,3, with annual rates comparable to those of deforestation4. However, its actual extent and long-term impacts remain uncertain at global tropical scale5. Here we quantify the magnitude and persistence of multiple types of degradation on forest structure by combining satellite remote sensing data on pantropical moist forest cover changes4 with estimates of canopy height and biomass from spaceborne6 light detection and ranging (LiDAR). We estimate that forest height decreases owing to selective logging and fire by 15% and 50%, respectively, with low rates of recovery even after 20 years. Agriculture and road expansion trigger a 20% to 30% reduction in canopy height and biomass at the forest edge, with persistent effects being measurable up to 1.5 km inside the forest. Edge effects encroach on 18% (approximately 206 Mha) of the remaining tropical moist forests, an area more than 200% larger than previously estimated7. Finally, degraded forests with more than 50% canopy loss are significantly more vulnerable to subsequent deforestation. Collectively, our findings call for greater efforts to prevent degradation and protect already degraded forests to meet the conservation pledges made at recent United Nations Climate Change and Biodiversity conferences.

The fragmented and complex landscape in the Miombo landscape makes it a challenge to map and disentangle the various forest change drivers (FCD) associated with these changes and relate them to other underlying drivers. To overcome these challenges, we developed a method to spatially disentangle the drivers of deforestation (smallholder and commercial agriculture, mining, and clean-cutting charcoal), forest degradation (selective charcoal production, wildfires, logging), and forest growth (abandoned land, regrowth including plantations) in the Beira corridor, in central Mozambique. We identified ten potential FCD from the literature and created two land use and land cover (LULC) maps for 2000 and 2020 to identify areas of forest change. We used stratified random sampling based on the LULC change map, visually interpreted high-resolution satellite imagery, and NDVI time series to characterise and collected observation points of the FCD. We derived several potential underlying drivers as explanatory spatial variables. We used the random forest algorithm to evaluate their relative importance and generate a map of FCD. The forest loss due to deforestation and degradation accounts for 82.8 % (38,553.1 ha year−1) and 5.2 % (2,399.1 ha year−1), respectively, while the gain due to plantations accounts for 2.8 % (1,314.4 ha year−1) and regrowth for 9.2 % (4,297 ha year−1) of the total forest change area from 2000 to 2020. Smallholder agriculture (72.2 % of the total forest change), clear-cutting charcoal (9.1 %), abandoned land (5.4 %) and regrowth (5.7 %) were the main FCD in the study area. They are explained mainly by the intensity of change, altitude, population density and proximity to the main road. The results show a satisfactory accuracy for the LULC map (overall accuracy = 88 % and F1-score = 80 % for LULC 2000 and 90 % and 88 % for LULC 2020) and for the FCD map (overall accuracy = 79 % and F1-score = 73 %). This study provides a significant improvement in quantify

Deforestation has been at the heart of the transformation of the Amazon. Global concerns over deforestation and its impact on climate change have resulted in the adoption of a number of initiatives in the framework of zero deforestation. However, undifferentiated application of the concepts of zero net, gross, and illegal deforestation has revealed a lack of understanding of their scope and of challenges to their implementation. Zero legal and illegal deforestation is, in particular, a controversial subject from the point of view of regulation and sovereignty but an essential aspect from the perspective of public policy design. In Colombia, zero deforestation commitments make no mention of legal deforestation. Papers that analyze deforestation and official data sources fail to incorporate the legal dimension in their analysis. This article addresses this gap by identifying areas where deforestation is legal and where it is illegal in one deforestation hotspot of the Colombian Amazon, the administrative department of Guaviare. Our results show that deforestation has increased since 2013, mainly occurs in illegal zones, and that Guaviare department, 85% of which is covered by forest, has very little legal deforestation potential. Our findings reveal that assessing the legality and illegality of deforestation is more complex than often assumed and must become a priority, especially in forested countries where regulation on forest and land management is shared between different level of governments and institutions.

Au cours des trente dernières années, plus de quatre cents millions d'hectares de forêts tropicales ont été détruits. À cette déforestation s'ajoute la dégradation forestière qui dans certaines régions du monde, comme l'Amazonie, affecte autant de surface que le déboisement. Préserver et conserver les forêts tropicales devient donc aujourd'hui une priorité pour la survie de l'humanité. Une première méthode consiste à sanctuariser les forêts en créant des aires protégées, limitant ainsi l'exploitation de leurs ressources par les humains. La seconde repose sur une exploitation raisonnée au bénéfice des populations locales et de la société en générale. Les forestiers privilégient cette méthode avec l'idée qu'une forêt valorisée générant des biens et des services aux populations, à l'État et à la société sera une forêt protégée et conservée. Cependant, la réalité sur le terrain continue de contredire ce principe. L'exploitation illégale, encore très répandue dans de nombreux pays tropicaux, engendre d'importants dégâts aux peuplements forestiers, et compromet leur capacité à se régénérer et à résister aux effets du changement climatique. L'exploitation du bois d'oeuvre est ainsi accusée de tous les maux et est très souvent considérée comme la principale source de déforestation. Cet essai vise non pas à réhabiliter l'exploitation forestière, mais à présenter de façon objective, factuelle et accessible aux personnes non spécialistes des forêts tropicales les effets environnementaux de l'exploitation du bois d'oeuvre. Il révèle les différentes voies possibles pour que cette exploitation devienne un véritable outil de conservation des forêts tropicales humides.

Firewood is a key energy source in developing countries, but its consideration for Life Cycle Assessment (LCA) purposes suffers from both data and methodological issues. A specific literature review revealed considerable variability in the way these issues have been addressed in existing studies. To improve current practices, a framework for proper inclusion of all environmental impacts related to traditional firewood uses is proposed, and a configurable dataset for other studies was produced. The framework was then applied to a case study on shea butter production, where firewood accounting appeared to be one of the main sources of discrepancies in the results of existing studies. For each parameter related to firewood uses and their impacts, data and methodological choices that LCA practitioners may face were then investigated through uncertainty and sensitivity analyses. Firewood consumption volumes and emission factors from firewood combustion proved to be the most critical parameters for all environmental issues, and the options explored in this study to tackle these data collection issues can be adapted to other case studies. Beyond data matters, the main methodological challenge for firewood accounting lies in estimating the fraction of firewood from non-renewable sources. Use of the default values from the spatially explicit supply-demand WISDOM model is recommended here. For the shea butter value chain in Burkina Faso, one of the main solutions for mitigating environmental impacts would be to reduce firewood consumption by promoting improved cookstoves, improving boiling practices, or replacing firewood with other biomass sources, such as shea nutshells.

Peatlands cover only 3–4% of the Earth's surface, but they store nearly 30% of global soil carbon stock. This significant carbon store is under threat as peatlands continue to be degraded at alarming rates around the world. It has prompted countries worldwide to establish regulations to conserve and reduce emissions from this carbon rich ecosystem. For example, the EU has implemented new rules that mandate sustainable management of peatlands, critical to reaching the goal of carbon neutrality by 2050. However, a lack of information on the extent and condition of peatlands has hindered the development of national policies and restoration efforts. This paper reviews the current state of knowledge on mapping and monitoring peatlands from field sites to the globe and identifies areas where further research is needed. It presents an overview of the different methodologies used to map peatlands in nine countries, which vary in definition of peat soil and peatland, mapping coverage, and mapping detail. Whereas mapping peatlands across the world with only one approach is hardly possible, the paper highlights the need for more consistent approaches within regions having comparable peatland types and climates to inform their protection and urgent restoration. The review further summarises various approaches used for monitoring peatland conditions and functions. These include monitoring at the plot scale for degree of humification and stoichiometric ratio, and proximal sensing such as gamma radiometrics and electromagnetic induction at the field to landscape scale for mapping peat thickness and identifying hotspots for greenhouse gas (GHG) emissions. Remote sensing techniques with passive and active sensors at regional to national scale can help in monitoring subsidence rate, water table, peat moisture, landslides, and GHG emissions. Although the use of water table depth as a proxy for interannual GHG emissions from peatlands has been well established, there is no single remot

Tropical forests play a crucial role in climate regulation due to their high carbon sequestration capacity. However, degradation and disturbances in these forests may result in significant carbon losses. This study focuses on the impact of various biophysical, anthropogenic, and landscape factors on aboveground biomass (AGB) in heavily disturbed landscapes of Côte d'Ivoire (West Africa), a typical low-forest and high-deforestation country. AGB estimates from a National Forest Inventory dataset have been linked to five categories of variables (Climate, Soil, Topography, Landscape, and Human-related) through a random forest modeling approach that addressed collinearity among variables, selected key variables from each category, and used spatial cross-validation to evaluate model performance. The comprehensive model, combining landscape composition, physical soil properties, and climate variables, demonstrated strong performance with an R-squared of 0.62. Notably, the percentage of landscape occupied by forest within a radius of 1000 m (PLAND1000) had a highly significant impact on AGB, exhibiting a notable increase when PLAND1000 exceeded 80 % and a decrease when it felt below 25 %. Soil properties, both physical (Bulk Density and Coarse Fraction) and chemical (soil pH), significantly influenced AGB, too. Interestingly, climatic, topographic, and other anthropogenic variables had minimal relevance in predicting AGB, suggesting that their effects may have been captured by landscape and soil integrative variables. In order to enhance forest preservation and restoration initiatives in the face of deforestation and fragmentation challenges in the West African region, we recommend (i) evaluating the appropriate landscape scale of effect (a 1000 m radius circle being the most significant in this study); (ii) prioritizing the preservation or restoration of dense forest landscapes; and (iii) integrating landscape composition into forest management policies.

Whilst the importance of fungal primary biological aerosol particles (PBAPs) has been recognised, few studies have empirically assessed how land-use patterns influence them. Here, we show the impacts of different land-use patterns on fungal PBAPs within the Brazilian Atlantic Forest biodiversity hotspot. Spanning a distance of ca. 600 km within this biome, we collected fungal bioaerosols in the following land-use patterns: a 25-year-old coffee plantation, a 2.5-year-old Eucalyptus plantation, a 3-months-old maize crop, a 2-year-old and another 7-year-old native forest reforestation area, and a native forest fragment. Using the portable Burkard air sampler, a total of 14 morphotype-species were found. Cladosporium sp. comprised as much as about 95% of all fungal spores collected, being present in all samples (frequency of 100%). Forest systems had as much as 5-to-19-fold more fungal spores in the air than maize crops. Sampling height and time (morning vs. afternoon) did not influence fungal concentration and number of species. In addition, using data derived from an eddy covariance tower in the Eucalyptus site, we estimated the emission rate to be 6649 spores m−2 s−1. Our study confirms that land-use patterns affect fungal PBAPs, and that replacing large areas of native Atlantic Forest by monospecific stands, a homogenisation of airborne fungi is occurring, with unknown consequences for climate regulation.

Many countries have integrated agroforestry into their sustainable development policies, particularly in Southeast Asia. In Timor-Leste, the national strategy to promote agroforestry has adopted a modern, technique-oriented approach focused on crop rotation, intercropping and agro-silvo-pasture. In so doing, it has largely overlooked the pre-existence, diversity and performance of traditional agroforestry systems (AFS). The data collected in seven villages located in four districts of the eastern municipalities of Timor-Leste identified five common AFS: home garden, crop field and fallow, young agroforest, forest garden and silvopastoralism. The combined use of the customary AFS by rural households depends on the households' ability to access the four types of capital (land, financial, labour and social) underpinning their development strategies. Four rural household archetypes were therefore distinguished. Six farming strategies used by these archetypes were identified: cattle specialisation, palm and tree product harvesting, crop intensification, diversification of off-farm and on-farm income, abandonment of farming, and survival. Each of these farming strategies combine certain customary AFS. The diversity and complexity of AFS require a better description of how they function and a better understanding of how they fit into the heterogeneous development strategies of rural households before actions are considered to improve their performance.

Understanding the effectiveness of conservation interventions during times of political instability is important given how much of the world's biodiversity is concentrated in politically fragile nations. Here, we investigate the effect of a political crisis on the relative performance of community managed forests versus protected areas in terms of reducing deforestation in Madagascar, a biodiversity hotspot. We use remotely sensed data and statistical matching within an event study design to isolate the effect of the crisis and post-crisis period on performance. Annual rates of deforestation accelerated at the end of the crisis and were higher in community forests than in protected areas. After controlling for differences in location and other confounding variables, we find no difference in performance during the crisis, but community-managed forests performed worse in post-crisis years. These findings suggest that, as a political crisis subsides and deforestation pressures intensify, community-based conservation may be less resilient than state protection.

For countries' emission-reduction efforts under the Paris Agreement to be effective, baseline emission/removals levels and reporting must be as transparent and accurate as possible. For Indonesia, which holds among the largest area of tropical peatlands and mangrove forest in the world, it is particularly important for these high-carbon ecosystems to produce high-accuracy greenhouse gas inventory and to improve national forest reference emissions level/forest reference level. Here, we highlight the opportunity for refining greenhouse gas emission factors (EF) of peatlands and mangroves and describe scientific challenges to support climate policy processes in Indonesia, where 55 to 59% of national emission reduction targets by 2030 depend on mitigation in Forestry and Other Land Use. Based on the stock-difference and flux change approaches, we examine higher-tier EF for drained and rewetted peatland, peatland fires, mangrove conversions, and mangrove on peatland to improve future greenhouse gas flux reporting in Indonesia. We suggest that these refinements will be essential to support Indonesia in achieving Forest and Other Land Use net sink by 2030 and net zero emissions targets by 2060 or earlier.

The vast peat deposits in the Peruvian Amazon are crucial to the global climate. Palm swamp, the most extensive regional peatland ecosystem faces different threats, including deforestation and degradation due to felling of the dominant palm Mauritia flexuosa for fruit harvesting. While these activities convert this natural C sink into a source, the distribution of degradation and deforestation in this ecosystem and related C emissions remain unstudied. We used remote sensing data from Landsat, ALOS-PALSAR, and NASA's GEDI spaceborne LiDAR-derived products to map palm swamp degradation and deforestation within a 28 Mha area of the lowland Peruvian Amazon in 1990–2007 and 2007–2018. We combined this information with a regional peat map, C stock density data and peat emission factors to determine (1) peatland C stocks of peat-forming ecosystems (palm swamp, herbaceous swamp, pole forest), and (2) areas of palm swamp peatland degradation and deforestation and associated C emissions. In the 6.9 ± 0.1 Mha of predicted peat-forming ecosystems within the larger 28 Mha study area, 73% overlaid peat (5.1 ± 0.9 Mha) and stored 3.88 ± 0.12 Pg C. Degradation and deforestation in palm swamp peatlands totaled 535,423 ± 8,419 ha over 1990–2018, with a pronounced dominance for degradation (85%). The degradation rate increased 15% from 15,400 ha y−1 (1990–2007) to 17,650 ha y−1 (2007–2018) and the deforestation rate more than doubled from 1,900 ha y−1 to 4,200 ha y−1. Over 1990–2018, emissions from degradation amounted to 26.3 ± 3.5 Tg C and emissions from deforestation were 12.9 ± 0.5 Tg C. The 2007–2018 emission rate from both biomass and peat loss of 1.9 Tg C yr−1 is four times the average biomass loss rate due to gross deforestation in 2010–2019 reported for the hydromorphic Peruvian Amazon. The magnitude of emissions calls for the country to account for deforestation and degradation of peatlands in national reporting.

Due to the lack of studies about the sociocultural dimension of ecosystem services, we analyze in this work the perception of these benefits by family farmers who have agroforestry systems in the northeast of Pará, in the Amazon region. With this objective, we categorize forest restoration strategies based on primary data collection - interviews, semi structured questionnaire, illustrated questionnaire and Likert Scale. Through the relative perception based on the application of Likert scales, we observed that the farmers recognize the benefits provided by agroforest systems and natural landscapes, with high perception of ecosystem services in all the categories present in the Millennium ecosystem evaluation. Furthermore, the higher perceptions of ecosystem services are related to the group of farmers with a smaller area of forest reserve and bigger area of agroforest systems. The result suggests that loss of forest area, at the individual level, probably drives to a higher sense of the benefits of natural systems and thus, the increment in agroforestry systems constitutes an attempt to return to functions and benefits lost through environmental degradation over time. In general, support programs are necessary to strengthen the capacity of agroforestry systems to provide ecosystem services and increase biodiversity conservation.

The future of most tropical sectors is clouded by growing constraints linked to, among many other parameters, climate change, price volatility and labour scarcity. Perpetuating agricultural systems inherited from the colonial era (a time of abundant arable land, protected markets, and cheap and disciplined labour) will not be enough to prepare these sectors in facing immediate crucial challenges unless substantial structural transformations are made. Implementing a successful agroecological transition in a 70-billion USD sector, covering 25 million ha worldwide, calls for drastic changes in mind-sets and practices. The key issue is no longer simply to increase productivity, but to foster innovations designed to support endangered tropical biodiversity, while providing a decent living for shrinking agricultural communities in the Global South. Agroforestry practices have a role to play in providing substantial climate change mitigation with an impact comparable to other climate-focused solutions, such as reforestation. The expected contribution of oil palm-based agroforestry relies on agro-environmental services, as basic agricultural functions such as soil preservation, pollination, or pest control can be ensured by living organisms inside and around the plantation. Diversified systems are able to achieve both economic and environmental gains, as they use land more efficiently than monocultures. Building on regenerative agriculture, new plantation designs are emerging and deserve to be thoroughly assessed to establish evidence-based advocacy for change.

Societal Impact Statement Yam plays an important role in ensuring food security in Côte d'Ivoire, serving as a staple crop for 60% of the population and a significant source of income. It holds deep cultural significance for the Akan and Gour ethnic groups. Preserving yam production is essential for both food security and the preservation of cultural heritage. However, productivity is decreasing while demand is expected to double in the next 30 years. Soil degradation and climate change are major threats to yam production. This article contextualizes the main factors threatening yam production (i.e., soil degradation and climate change) and discusses the consequences and ways to mitigate them. Summary The anticipated twofold increase in Côte d'Ivoire's population within the next three decades poses a significant challenge for agricultural research to sustain food security. Despite being an under-researched and often neglected crop, yam remains the primary staple food and a crucial source of income in the country. With an annual estimated market value of over 2000 billion CFA francs, yam ranks among the top five most economically valuable crops in Côte d'Ivoire. For the past 15 years, yam production has experienced a decline in productivity, which has been compensated for by expanding the cropped area. Unfortunately, this approach exacerbates the risk of deforestation and soil degradation. Additionally, the impact of climate change on yam production, coupled with a lack of financial resources to address it, has rendered this unsustainable mode of production even more precarious. The purpose of this study is to provide an overview of the effects of climate change on yam production in Côte d'Ivoire. We investigated the reasons for the productivity decline and described the risks on food security. Furthermore, we explained how varietal innovation of Dioscorea alata could play a critical role in mitigating these effects and outlined related research avenues that need to

Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system. Remote-sensing estimates to quantify carbon losses from global forests are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these estimates. Here we combine several ground-sourced and satellite-derived approaches to evaluate the scale of the global forest carbon potential outside agricultural and urban lands. Despite regional variation, the predictions demonstrated remarkable consistency at a global scale, with only a 12% difference between the ground-sourced and satellite-derived estimates. At present, global forest carbon storage is markedly under the natural potential, with a total deficit of 226 Gt (model range = 151–363 Gt) in areas with low human footprint. Most (61%, 139 Gt C) of this potential is in areas with existing forests, in which ecosystem protection can allow forests to recover to maturity. The remaining 39% (87 Gt C) of potential lies in regions in which forests have been removed or fragmented. Although forests cannot be a substitute for emissions reductions, our results support the idea that the conservation, restoration and sustainable management of diverse forests offer valuable contributions to meeting global climate and biodiversity targets.

En Côte d'Ivoire, l'agroforesterie devient une notion incontournable après une déforestation massive pour les cultures de plantation. Depuis les années 2010, le terme se généralise dans le vocabulaire politique, les normes internationales de durabilité et la communication des entreprises chocolatières. Cette note examine comment l'agroforesterie s'est imposée dans l'agenda politique ivoirien. Adoptant une approche compréhensive et à partir d'une soixantaine d'entretiens et des documents politiques, elle analyse la manière dont la notion d'agroforesterie est mobilisée en Côte d'Ivoire, les instruments de sa promotion et les controverses qu'elle suscite. D'abord, ce travail montre que la mise à l'agenda de l'agroforesterie en Côte d'Ivoire se fait suivant des canaux pluriels. Différents instruments de promotion de l'agroforesterie se côtoient, tels que les normes de certification privée, la norme africaine régionale de durabilité pour le cacao, les paiements pour services environnementaux ou encore un dispositif national dit " Agro-Forêt ", issu du nouveau Code forestier. Ensuite, malgré le consensus sur la promotion de l'agroforesterie, sa définition large permet à des acteurs aux intérêts divergents de s'approprier le concept. Ce travail met par ailleurs en évidence la pluralité des objectifs et des perspectives que recouvre la notion en Côte d'Ivoire. Il identifie ainsi des controverses concernant les critères du système agroforestier, sa finalité, la place des agriculteurs, l'échelle d'analyse et la temporalité à considérer. En définitive, cette note contribue à expliciter les traductions politiques plurielles d'une notion issue des sciences. Les liens complexes entre les recherches biophysiques et la pratique politique soulignent l'importance de prendre en compte cette interface pour une meilleure conception de l'agroforesterie et une transition efficace.

L'émergence de l'agroforesterie en Côte d'Ivoire est devenue une priorité nationale. Le secteur agricole du pays génère 70 % des recettes d'exportation, emploie les deux tiers de la population active et contribue à un tiers du PIB. Cependant, ces performances économiques remarquables reposent sur une agriculture de rente qui se développe au détriment des forêts naturelles, entraînant l'un des taux de déforestation les plus alarmants au monde. Pour faire face à cette situation, l'État ivoirien promeut l'agroforesterie comme solution, en particulier dans le secteur du cacao. Cependant, une analyse fine de l'origine des arbres présents dans les champs suggère que l'agroforesterie en Côte d'Ivoire peut être divisée en deux catégories : l'agroforesterie de reforestation, qui permet de reconstituer le couvert forestier en associant progressivement des arbres aux cacaoyers, et l'agroforesterie de déforestation, qui dégrade et appauvrit la couverture forestière en convertissant les forêts naturelles en systèmes agroforestiers. Il est crucial de distinguer ces deux formes d'agroforesterie afin de développer des politiques qui encouragent la reforestation plutôt que la déforestation. Il est également nécessaire de mettre en place des indicateurs dynamiques qui permettent d'évaluer les trajectoires agroforestières des champs dans le temps et, ainsi, de favoriser un engagement à long terme des agriculteurs dans l'augmentation de la couverture forestière.

Les certifications privées de durabilité appliquées aux filières soja, bois, huile de palme et cacao constituent des outils prometteurs pour lutter contre la déforestation sous les tropiques. Cependant, aucun de ces standards n'est aujourd'hui pleinement compatible avec les exigences énoncées dans la SNDI. D'autres approches de lutte contre la déforestation sont envisageables, comme une réglementation contraignante, la gestion du risque géographique ou la promotion de territoires durables. Ces démarches peuvent concerner des filières encore peu engagées dans la certification et impliquer plus facilement les petits producteurs. Les avantages de recourir à la certification sont optimisés lorsqu'elle est combinée aux autres instruments de lutte contre la déforestation importée. La prochaine mise en oeuvre du règlement contre la déforestation de l'Union européenne illustrera par exemple dans quelle mesure le mécanisme de diligence raisonnée s'appuiera ou pas sur les standards de durabilité pour limiter le risque de déforestation dans les pays à risque.

In the context of Global Change Research, detection, monitoring and characterization of land use/land cover (LULC) changes are of prime importance. The increasing availability of dense satellite image time series (SITS) has led to a shift in the change detection paradigm, with algorithms able to exploit the full temporal information laid down in SITS. So far, most of these algorithms have focused on the detection of abrupt and gradual changes, and thus developed breakpoint detection based on significant deviations from the mean. However, LULC changes may manifest themselves in other patterns, particularly changes in seasonality (amplitude, number and length of the growing seasons) that are harder to detect. In this paper, we propose a simple method to automatically select the breakpoint linked to the biggest seasonal change in long and dense SITS with multiple breakpoints. This approach - BFASTm-L2 - relies on linking a high-speed algorithm (BFAST monitor) with a time series similarity metric (Euclidian distance L2) sensitive to seasonal changes. The capacity of BFASTm-L2 to identify the date of change in different situations was tested on two data sets, and compared to the performances of three other algorithms (BFAST monitor, BFAST lite, and Edyn). The data sets are 1. a published benchmark data set composed of 25 200 simulated SITS with different change types and change magnitudes, and 2. the 2000–2020 MODIS NDVI SITS over a 200x200 pixels area in Senegal including different study sites which have undergone recent LULC changes due to agricultural large-scale land acquisitions (LSLAs) (as reported in the ground field database used in this study). The results show that BFASTm-L2 is efficient in accurately detecting in time most of the changes, and, in contrast with BFAST Lite and BFASTmonitor, to spatially highlight LSLAs-induced changes without the need of any prior knowledge. The automatic proposed approach, faster than BFAST Lite and Edyn, and with very few tune

Until recently, little or no use was made of fiscal instruments for forest protection in developing countries. The rise of independent third-party certification systems since the 1990s opens new perspectives for using taxation as an incentive. In the forestry sector, certification has developed significantly in Central Africa but reached a plateau in the last ten years, apparently due to the reorientation of timber export flows towards Asian markets that do not demand certified products. Fiscal incentives, through tax cuts for responsible producers, could compensate for the absence of price premiums but would diminish public revenues. The principle of the "bonus-malus" (feebates) seems promising to the extent that it does not reduce government budgetary revenues (budget neutrality). Bonus-malus schemes can also promote certified "zero deforestation" or "grown in agroforestry" agricultural production, especially cocoa, a significant driver of deforestation in Africa. Governments can select one or several certification schemes, private or public ones, and target fiscal incentives related to these certified products. The peculiarity of a bonus-malus system is that the revenues generated by the malus are expected to decrease progressively (with the adoption of certification), requiring a reduction of the bonus rates in order to respect budget neutrality. Adopting such a scheme would create winners and losers, therefore, complementary policy measures targeting small-scale producers are desirable.

Payments for environmental services (PES) have been widely studied as one possible way to counter deforestation and support livelihoods. Given the high rates of deforestation in the Amazon region, it is important to study under which conditions PES have positive environmental and social outcomes. We contribute to this debate through a systematic review based on the Realist Evaluation framework. First, we review case studies to identify configurations of social-ecological factors (context), PES design and implementation (resource mechanisms), people's responses (reasoning mechanisms), and the results in terms of forest conservation and people's livelihoods (outcomes). Second, we develop a middle-range theory of how, for whom, and under what conditions PES in the Amazon achieve these results. After screening 972 articles in the SCOPUS, Scielo, and WorldCat databases, we reviewed 13 articles in-depth that contained all the elements (context-mechanism-outcomes) needed to identify these configurations. Our results show that PES in the Amazon generate positive environmental and social outcomes when they: (a) combine cash and in-kind incentives, (b) raise environmental awareness through capacity building, (c) engage socially and ethnically diverse stakeholders through equitable and inclusive approaches, (d) apply transparent spatial targeting, (e) guarantee strong conditionality through robust monitoring of compliance, and (f) guarantee stable delivery of payments.

The consistent monitoring of trees both inside and outside of forests is key to sustainable land management. Current monitoring systems either ignore trees outside forests or are too expensive to be applied consistently across countries on a repeated basis. Here we use the PlanetScope nanosatellite constellation, which delivers global very high-resolution daily imagery, to map both forest and non-forest tree cover for continental Africa using images from a single year. Our prototype map of 2019 (RMSE = 9.57%, bias = −6.9%). demonstrates that a precise assessment of all tree-based ecosystems is possible at continental scale, and reveals that 29% of tree cover is found outside areas previously classified as tree cover in state-of-the-art maps, such as in croplands and grassland. Such accurate mapping of tree cover down to the level of individual trees and consistent among countries has the potential to redefine land use impacts in non-forest landscapes, move beyond the need for forest definitions, and build the basis for natural climate solutions and tree-related studies.

Land use change is one of the most important determinants of carbon storage and dynamics in ecosystems. Areas in the proximity of metropoles undergo land use changes but are poorly studied for their soil and biomass carbon budget, especially in Africa. Close to Benin's economic capital, the Lama Territory located on the Allada Plateau and is subject to high demographic and urbanization pressures. Carbon (C) stocks in the region are likely to be rapidly changing. This research assessed the land use changes and quantified the spatial distribution and variation of C stocks between 2000 and 2018 on the Ferralsols of the study area. Random forest models using spectral bands of LANDSAT images and some spectral indices as predictors were calibrated to classify the land use. C stocks of four C pools (aboveground, belowground biomass, litter, and soil) were mapped with InVEST (integrated valuation of ecosystem services and tradeoffs) model. Land use change occurred in 61% of the Ferralsol area between 2000 and 2018. The surface of forests and crop-plantation associations decreased in benefit of tree plantations, adult palm groves, and built-up areas. With the loss of forest surface and the increasing urbanization, C stocks of the region decreased by −218 Gg C with 4% uncertainty (−175 Gg C in soil pools, and − 125 Gg C in aboveground biomass with both 6% uncertainty) between 2000 and 2018. Results highlight: (i) the need for soil C stock accounting to avoid underestimation of C stocks evolution in a rural region; and (ii) the relevance of tree plantations and deforestation control to maintain the C stocks in tropical areas.

Integrated landscape approaches that engage diverse stakeholder groups in landscape governance are increasingly promoted to address linked social–ecological challenges in tropical landscapes. Recent research suggests that a transdisciplinary approach to landscape management can help identify common research needs, enhance knowledge co-production, guide evidence-based policy development, and harmonize cross-sectorial integration. Meanwhile, guiding principles for landscape approaches suggest that identifying common concerns and negotiating a process of change are fundamental to implementation and evaluation efforts. As such, the use of decision support tools such as theory of change models that build ordered sequences of actions towards a desired, and agreed, future state are increasingly advocated. However, the application of the theory of change concept to integrated landscape approaches is limited thus far, particularly within the scientific literature. Here, we address this gap by applying the principles of landscape approaches and knowledge co-production to co-produce a theory of change to address current unsustainable landscape management and associated conflicts in the Kalomo Hills Local Forest Reserve No. P.13 (KFR13) of Zambia. The participatory process engaged a diverse range of stakeholders including village head people, local and international researchers, district councillors, and civil society representatives amongst others. Several pathways, actions, and interventions were developed around the themes of deforestation, biodiversity and wildlife conservation, socio-economic development, access rights, and law enforcement. To make the theory of change actionable, participants identified a need for enhanced cross-sector and multi-level communication, capacity development, and improved governance, while a lack of commitment towards coordinated knowledge exchange and access to information along with poor policy formulation and weak enforcement of rules were

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution.

Purpose of Review: Increasing the diversity of commercial tree plantations is a promising approach to adapt forests to climate change, but it may complicate management. Here, we evaluate stakeholders' perspectives about tree-species diversity in plantations and explore policy alternatives to make mixed plantations a viable strategy for climate change mitigation and adaptation. Recent Findings: Current evidence shows that improving the diversity of tree species in plantations can be a viable, scalable, and economically accessible strategy for sustainable wood production and reconciling economic and environmental benefits. Tree diversity is particularly important in the context of global environmental changes and associated increases in abiotic and biotic stresses, such as severe droughts and pest outbreaks. Even though there is substantial scientific evidence supporting mixed-tree plantations, most forest plantations globally are still conventional monocultures. Summary: Our findings (i) describe the geographical distribution of publications investigating human perspectives about forest plantation diversity; (ii) build understanding of how political engagement and governance systems can support forest initiatives on forest conservation, management, and restoration; and (iii) demonstrate how these perspectives can create possibilities and opportunities for sustainable development in forestry. We conclude that new strategies will only be widely applied if there is political and institutional interest, particularly in strengthening land-governance systems.

Much concern about tropical deforestation focuses on oil palm plantations, but their impacts remain poorly quantified. Using nation-wide interpretation of satellite imagery, and sample-based error calibration, we estimated the impact of large-scale (industrial) and smallholder oil palm plantations on natural old-growth (“primary”) forests from 2001 to 2019 in Indonesia, the world's largest palm oil producer. Over nineteen years, the area mapped under oil palm doubled, reaching 16.24 Mha in 2019 (64% industrial; 36% smallholder), more than the official estimates of 14.72 Mha. The forest area declined by 11% (9.79 Mha), including 32% (3.09 Mha) ultimately converted into oil palm, and 29% (2.85 Mha) cleared and converted in the same year. Industrial plantations replaced more forest than detected smallholder plantings (2.13 Mha vs 0.72 Mha). New plantations peaked in 2009 and 2012 and declined thereafter. Expansion of industrial plantations and forest loss were correlated with palm oil prices. A price decline of 1% was associated with a 1.08% decrease in new industrial plantations and with a 0.68% decrease of forest loss. Deforestation fell below pre-2004 levels in 2017–2019 providing an opportunity to focus on sustainable management. As the price of palm oil has doubled since the start of the COVID-19 pandemic, effective regulation is key to minimising future forest conversion.

On the outskirts of the city of Bangui, the capital of the Central African Republic, fuelwood production, slash-and-burn agriculture and artisanal timber exploitation are causing deforestation and forest ecosystem degradation. Within the framework of the REDD+ Component of the South-West Regional Development Project, the implementation of Assisted Natural Regeneration during weeding (ANRw) in the slash-and-burn system was proposed and set up by 23 volunteer farmers on 24 fields with an average area of 0.22 ha in two villages (Boteke and Salanga). The objective of the study was to characterise the floristic structure of the juvenile woody vegetation resulting from ANRw in these two villages. More specifically, it aimed to: 1) describe the methods used to inform and raise awareness amongst farmers who volunteer to practise ANRw; 2) identify the main species conserved by the farmers; 3) identify the reasons or factors that motivated farmers to choose these species; 4) identify the biological and ecological characteristics of these species; and 5) evaluate the height growth of young trees preserved by ANRw over a 14-month period. The third inventory of the 24 plots (volunteers' fields) gave 1,668 woody plants preserved by ANR on 5.35 ha (312 trees ha−1), divided into 42 genera, 47 species and 23 families. These results show that ANRw is a simple technique to implement and can help maintain trees in fields in areas where pressure on the forest is high. In the supported villages, communities have shown an interest in applying this technique to reintroduce trees in the fields. This technique should be popularised in other places to improve the sustainable management of anthropized forest landscapes. In addition, volunteers who have tested ANRw say they are willing to continue practicing it. However, despite this genuine initial enthusiasm, this restoration drive will need to be monitored and supported due to the current context of extreme poverty and economic, social and p

Hundreds of projects to reduce emissions from deforestation and forest degradation and enhance carbon stocks (REDD+) are implemented globally, many by non-governmental organizations (NGOs) or for-profit companies. Yet, at the global level, the Paris Agreement focuses on jurisdictional (national and subnational) REDD+. We ask: (1) How much can REDD+ projects contribute to achieving national and international climate objectives? (2) What are the issues in integrating REDD+ projects into national carbon accounting? Our snapshot of 377 REDD+ projects covering 53 million ha in 56 countries is based on data from the International Database on REDD+ Projects (ID-RECCO) supplemented with new data on projects' accounting methods. The number of new REDD+ projects declined steadily from 45 new projects in 2011 to five in 2019. We examined 161 certified projects that started between 2007 and 2017; 96 of these could sell carbon credits in voluntary carbon markets by 2020 and spent on average 4.7 (± 2.4) years between project start and sales in voluntary carbon markets. Globally, REDD+ projects claim to reduce an average of 3.67 tCO2e/ha annually. This figure - combined with projects limited coverage - implies that projects need to be upscaled more than 40x to fulfil the potential contribution of tropical and subtropical forests towards limiting global warming to well below 2oC. Compared to the national carbon accounting methods, most projects in Colombia, Indonesia and Peru (63 of 86) use at least one different carbon accounting parameter. Carbon accounting inconsistencies across levels need to be addressed. Overall, the argument for REDD+ projects lies in the emissions reductions they can achieve, diversifying participation in REDD+ and providing non-carbon benefits to local communities, potentially leading to broader support for climate action.

Natural rubber consumption has led to the expansion of rubber (Hevea brasiliensis) plantations which affects the deforestation and ecosystem. However, no study of the long-term effect of rubber plantations on soil biodiversity has been carried out yet. This study aimed to assess the long-term impact of continuous rubber monocropping on soil biodiversity, focusing on soil macrofauna and nematode diversity. Three successive rubber rotations at young and old ages were compared with the adjacent forest in Suratthani province, Thailand. Soil biodiversity quality index was calculated from a set of indicators which were combined into a single score to present a functional assessment of the gradient of disturbance. The results showed three negative effects on soil biodiversity (i) the biodiversity quality index immediately declined after deforestation (ii) the old age rubber plantations had a lower soil biodiversity as the nematodes were a main driver of diversity in the young plantation, and (iii) similarly, for the soil chemical properties, the long-term effect of rubber chronosequence evidenced deterioration in the third rotation. Therefore, two rotations of rubber plantation (around 50 years) seemed to be the maximum length of rubber monocropping in terms of soil biodiversity recovery.

Metrics of hydrological mimicry ('mimetrics') reflect similarity in ecological structure and/or functions between managed and natural ecosystems. Only the land-surface parts of hydrological cycles are directly visible and represented in local knowledge and water-related legislation. Human impacts on water cycles (HIWC) can, beyond climate change, arise through effects on local and regional hydrological processes, from both reduced and increased water use compared to a natural reference vegetation with which landscape structure and hydrology are aligned. Precipitationsheds, the oceanic and terrestrial origin of rainfall, depend on evapotranspiration and thus on vegetation. The political commitment to reduce agricultural impact on nature requires hydrological mimetrics to trickle down through institutions to actions. Existing metrics do not suffice. For example, the water footprint metric that relates agricultural water use to consumption decisions, suggests minimizing water use is best, ignoring full hydrological impacts. We explore principles, criteria and indicators for understanding HIWC, via modified evapotranspiration, effects on streamflow (downstream impacts) and atmospheric fluxes and precipitation (downwind impacts). Comprehensive HIWC mimetrics for a set of pantropical watersheds suggest hydrological mimicry options for forest-derived land use patterns through intermediate densities of trees with diversity in rooting depth and water use, interacting with soils, crops and livestock.

Unless amended, draft rules to ban deforestation-tainted commodities could unfairly penalize less-developed countries.

Mineral nitrogen (N) application in agriculture has significantly increased food production over the past century. However, the intensive use of N fertilizers also impacts negatively the environment, notably through greenhouse gas emissions and biodiversity loss and remains a major challenge for policymakers. In this paper, we explore the effects of a public policy aiming at halving agricultural mineral nitrogen use across the European Union (EU). We investigate the impacts on food security, climate mitigation, and biodiversity conservation and we analyze the potential trade-offs and synergies between them. Despite the uncertainties associated with monetary valuation and the choice of modeling approach, our results show that climate- and biodiversity-related benefits of halving N use in EU agriculture more than offset the decrease in agricultural benefits.

The usefulness of global integrated assessment model (IAM) results for policy recommendation in specific regions has not been fully assessed to date. This study presents the variation in results across models for a given region, and what might be behind this variation and how model assumptions and structures drive results. Understanding what drives the differences across model results is important for national policy relevance of global scenarios. We focus on the use of bioenergy in Brazil, a country expected to play an important role in future bioenergy production. We use results of the Stanford University Energy Modeling Forum's 33rd Study (EMF-33) model comparison exercise to compare and assess projections of Brazil's bioenergy pathways under climate mitigation scenarios to explore how 10 global IAMs compare to recent trends in the country. We find that, in their current form, global IAMs have limited potential to supply robust insights into regional mitigation strategies. Our results suggest fertile ground for a new research agenda to improve regional representation in global IAMs with improved spatial and technological resolutions.