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Madagascar is one of the most burned regions in the world, to the point that it has been called the ‘Isle of fire’ or the ‘Burning Island’. An accurate characterization of the burned area (BA) is crucial for understanding the true situation and impacts of fires on this island, where there is an active scientific debate on how fire affects multiple environmental and socioeconomic aspects, and how fire regimes should be in a complex context with differing interests. Despite this, recent advances have revealed that BA in Madagascar is poorly characterised by the currently available global BA products. In this work, we present, validate, and explore a BA database at 20 m spatial resolution for Madagascar covering the period 2016–2022. The database was built based on 75,010 Sentinel-2 images using a two-phase BA detection algorithm. The validation with independent long-term reference units showed Dice coefficients ≥79 %, omission errors ≤24 %, commission errors ≤18 %, and a relative bias ≥ − 8 %. An intercomparison with other available global BA products (GABAM, FireCCI51, C3SBA11, or MCD64) demonstrated that our product (i) exhibits temporal consistency, (ii) represents a significant accuracy improvement, as it reduces BA underestimations by about eightfold, (iii) yields BA estimates four times higher, and (iv) shows enhanced capability in detecting fires of all sizes. The observed BA spatial patterns were heterogeneous across the island, with 32 % of the grasslands burning annually, in contrast to other land cover types such as the dense tropical forest where <2 % burned every year. We conclude that the BA characterization in Madagascar must be addressed using imagery at spatial resolution higher than MODIS or Sentinel-3 (≥250 m), and temporal resolution higher than Landsat (16 days) to deal with cloudiness, the rapid attenuation of burn scars signals, and small fire patches.

The Anthropocene draws attention to how humans have increasingly shaped forests in the past, how forest loss and forest planting play a key role in today’s climate emergency, and how we think about forests and forest stewardship in the future. In this handbook entry I review the human moulding of forests, both constructive and destructive, since prehistoric times and suggest a conceptualization that explicitly incorporates human elements among the many processes constituting forests.

From ornamentals and rehabilitators to resources and invaders, Australian Acacia species (‘wattles’) have assumed diverse roles over time in the varied landscapes to which they have been introduced. The reception of these species – linked to how they are used, peoples’ perceptions about the trees’ and shrubs’ place in particular a landscape, and the environmental and socio-economic context – changes over time. In a context where wattles are sometimes important economic resources, sometimes subject to concerns over invasion, and where the climate emergency leads to pushes for rapid tree planting, the question is raised of how the place of wattles in human landscapes may evolve into the future. We sought to identify recent trends in how wattles are welcomed (or not), used (or not) and managed (or not) by people around the world. A conceptual model is proposed to understand how and why wattles are adopted and perceived differently in different places; this highlights moments of large, rapid, irreversible and systemic change, or regime shifts. We undertook a limited global online survey involving 72 respondents with knowledge on different wattle landscapes. Respondents were asked about changes in wattle extent, use, impact, perception and management over the past 10–15 years. We found that wat- tle social-ecological systems are dynamic: respondents reported more change than stability. They noted more wattle expansion than shrinkage; a number of increased uses; mostly amplifications (and some reductions) of previously reported impacts, both good and bad; generally increased awareness of invasions; and they commented on a number of management efforts both for forestry and for invasion control. Some changes are major and irreversible, such as the conversion over two decades of at least 6% of Vietnam’s land area to wattle plantations and accompanying institutional, economic, social and ecological shifts. Others are more incremental and perhaps reversible, such as public per

Vietnam is the country with the largest area of plantations of Australasian Acacia species (‘wattles’) in South-East Asia. Between 6 and 9% of the national land area is cultivated with tropical wattles (A. auriculiformis, A. mangium and A. × mangiiformis). From the perspective of its promoters, the wattle plantation industry in Vietnam may be seen as a success beyond expectations. We review the origins of this boom and ask what it has done to and for the coun- try’s landscape and people. The chapter combines findings and insights from an interdisciplinary research project in Thừa Thiên Huế province, north-central Vietnam. Research took place across upland and lowland wattle-growing regions, with ethnic minorities as well as the Kinh majority, and with long-term wattle growers as well as new en- trants. It drew on questionnaires, interviews and observations, as well as information from remote sensing, eco- logical surveys and hydrological assessments. We first describe how substantial areas of ‘new forest’ (short-rotation wattle plantations) were created, initially in degraded bushland, but now sometimes through clearing of highly bi- odiverse natural forest stands. These wattle plantations alter local hydrology, soils and biodiversity, and are exposed to risks including soil erosion and plant pathogens. The plantations provide wood chips and timber, supporting rev- enue, employment and a strong forestry industry. Incomes have risen appreciably for many, although unequally, and a class of successful entrepreneurs has emerged. These plantations alter the livelihoods and identities of upland ‘forest people’, historically shifting cultivators, contributing to what might be called ‘new forest people’. Ethnic mi- nority villagers are building new identities around the wattle economy and around their contracts with state forest agencies, seeing themselves increasingly as forest growers and protectors. We conclude by raising some questions regarding the social changes and i

Tapia woodlands (bois de tapia), named after the dominant tapia tree (Uapaca bojeri, Phyllanthaceae), are a type of vegetation found in highland zones of central and southwestern Madagascar. These woodlands are among the few, widely scattered examples of ‘native’ woody formations found in the highlands (along with the forests at Ambohitantely, Bongolava, Ankaratra, and Andringitra). This chapter surveys tapia woodlands, looking at their characteristics, origins, their use by humans, and their management, especially by fire.