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Shifting cultivation, an age-old agricultural practice, is a major factor in forest cover change across Southeast Asia, where repeated cycles of vegetation disturbance and regrowth lead to far-reaching environmental and socio-economic impacts. The present study aims to assess the spatio-temporal patterns of vegetation disturbance and regrowth caused by shifting cultivation in Tripura state of India, over the past three decades, utilizing temporal segmentation of time-series Landsat data. The study analyzed vegetation disturbance and regrowth patterns in a shifting cultivation landscape from 1991 to 2020 using normalized burn ratio trends through LandTrendr, validated by the TimeSync tool. Six land use and land cover classes, viz., forests and trees outside forests, rubber plantation, shifting cultivation, water bodies, agriculture, and settlements, were mapped with an accuracy of 83.08% using a random forest classifier. This classification enabled the identification of the effective study area, which included forest areas with shifting cultivation patches. The analysis revealed that 2533.96 km2 of the study area remained undisturbed, 568.43 km2 experienced low-magnitude disturbance, 1501.11 km2 were moderately disturbed, and 184.82 km2 were highly disturbed. The shifting cultivation cycles in the study area show considerable variation. Low-magnitude disturbance indicates a single slash-and-burn event in the past three decades, moderate-magnitude disturbance involves fallow periods of over 10 years, and high-magnitude disturbance occurs with fallow periods of less than 8 years. The study revealed a shift from traditional shifting cultivation to more permanent agricultural practices in parts of Tripura. In response to incentives for commercial crops, cultivators are increasingly adopting long-term cultivation, including the growing of pineapple, areca nut, and rubber, as well as intercropping with papaya, banana, lemon, tapioca, pepper, and ginger. These plots are, however, abandoned if the yields become economically unviable. The expansion of monoculture cultivation significantly reduces the available area for shifting cultivation, thereby compelling jhum cultivators to revisit their jhum patches more frequently. This study is a first-of-its-kind attempt in the Indian context and sheds light on changing patterns in an age-old agricultural practice. [ABSTRACT FROM AUTHOR]

Abstract Shifting cultivation, an age-old agricultural practice, is a major factor in forest cover change across Southeast Asia, where repeated cycles of vegetation disturbance and regrowth lead to far-reaching environmental and socio-economic impacts. The present study aims to assess the spatio-temporal patterns of vegetation disturbance and regrowth caused by shifting cultivation in Tripura state of India, over the past three decades, utilizing temporal segmentation of time-series Landsat data. The study analyzed vegetation disturbance and regrowth patterns in a shifting cultivation landscape from 1991 to 2020 using normalized burn ratio trends through LandTrendr, validated by the TimeSync tool. Six land use and land cover classes, viz., forests and trees outside forests, rubber plantation, shifting cultivation, water bodies, agriculture, and settlements, were mapped with an accuracy of 83.08% using a random forest classifier. This classification enabled the identification of the effective study area, which included forest areas with shifting cultivation patches. The analysis revealed that 2533.96 km2 of the study area remained undisturbed, 568.43 km2 experienced low-magnitude disturbance, 1501.11 km2 were moderately disturbed, and 184.82 km2 were highly disturbed. The shifting cultivation cycles in the study area show considerable variation. Low-magnitude disturbance indicates a single slash-and-burn event in the past three decades, moderate-magnitude disturbance involves fallow periods of over 10 years, and high-magnitude disturbance occurs with fallow periods of less than 8 years. The study revealed a shift from traditional shifting cultivation to more permanent agricultural practices in parts of Tripura. In response to incentives for commercial crops, cultivators are increasingly adopting long-term cultivation, including the growing of pineapple, areca nut, and rubber, as well as intercropping with papaya, banana, lemon, tapioca, pepper, and ginger. These plots are, however, abandoned if the yields become economically unviable. The expansion of monoculture cultivation significantly reduces the available area for shifting cultivation, thereby compelling jhum cultivators to revisit their jhum patches more frequently. This study is a first-of-its-kind attempt in the Indian context and sheds light on changing patterns in an age-old agricultural practice.

This study contributes to understanding ecological changes in land use following slash-and-burn land clearing. This study aimed to compare the richness and density of plant species and soil fertility in farmland cultivated for one year (1 Y), three years (3 Y), and five years (5 Y) after slash-and-burn, with the conditions in the secondary forest (SF) in Berau Regency of East Kalimantan. Understory plant taxon types, numbers, and soil organic matter were measured in each region using a series of nested plots. The size of each observation plot was 20 x 100 m. Data on understory vegetation composition was collected using 1 x 1 m mini plots at 20 sampling points and divided into five blocks, with a 10 m spacing between sampling points on each property. Understory vegetation species and cover percentage, litter cover percentage, open soil percentage, and soil fertility were measured for each observation plot. The results showed that the land cover percentage increased each year during the 5 years transition from secondary forest to farmland. Furthermore, within the 5 years, there was a change in understory species, particularly the presence of grasses and sedges at 3 and 5 years after the land use change. However, the transition from secondary forest to farmland within 5 years did not alter soil organic matter and total nitrogen.

Fire, a prevalent land management tool in rotational shifting cultivation (RSC), has long been debated for its immediate disruption of surface soil, vegetation, and microbial communities. While low-intensity and short-duration slash-and-burn techniques are considered beneficial for overall soil function, the dual nature of fire's impact warrants a comprehensive exploration. This review examines both the beneficial and detrimental effects of fire on soil properties within the context of RSC. We highlight that research on soil microbial composition, carbon, and nitrogen dynamics following fire events in RSC is gaining momentum. After fires, soil typically shows decreases in porosity, clay content, aggregation, and cation exchange capacity, while sand content, pH, available phosphorus, and organic nitrogen tend to increase. There remains ongoing debate regarding the effects on bulk density, silt content, electrical conductivity, organic carbon, total nitrogen, and exchangeable ions (K+, Ca2+, Mg2+). Certain bacterial diversity often increases, while fungal communities tend to decline during post-fire recovery, influenced by the soil chemical properties. Soil erosion is a major concern because fire-altered soil structures heighten erosion risks, underscoring the need for sustainable post-fire soil management strategies. Future research directions are proposed, including the use of advanced technologies like remote sensing, UAVs, and soil sensors to monitor fire impacts, as well as socio-economic studies to balance traditional practices with modern sustainability goals. This review aims to inform sustainable land management practices that balance agricultural productivity with ecological health in RSC systems. [ABSTRACT FROM AUTHOR]

This study contributes to understanding ecological changes in land use following slash-and-burn land clearing. This study aimed to compare the richness and density of plant species and soil fertility in farmland cultivated for one year (1 Y), three years (3 Y), and five years (5 Y) after slash-andburn, with the conditions in the secondary forest (SF) in Berau Regency of East Kalimantan. Understory plant taxon types, numbers, and soil organic matter were measured in each region using a series of nested plots. The size of each observation plot was 20 x 100 m. Data on understory vegetation composition was collected using 1 x 1 m mini plots at 20 sampling points and divided into five blocks, with a 10 m spacing between sampling points on each property. Understory vegetation species and cover percentage, litter cover percentage, open soil percentage, and soil fertility were measured for each observation plot. The results showed that the land cover percentage increased each year during the 5 years transition from secondary forest to farmland. Furthermore, within the 5 years, there was a change in understory species, particularly the presence of grasses and sedges at 3 and 5 years after the land use change. However, the transition from secondary forest to farmland within 5 years did not alter soil organic matter and total nitrogen. [ABSTRACT FROM AUTHOR]

This study addresses the contextual vulnerability of farmers using participatory risk mapping with different stakeholders. Additionally, through logistic regression, it identifies factors that influence the perception of climate risk. The results indicate that the perception and relevance of stressors vary among different stakeholders, as well as among farmers of different genders and ages. Non-climatic stressors are more relevant to farmers' livelihoods than climatic ones, although their interaction can exacerbate the impacts. Non-climate stressors identified in the past in the region continue to exacerbate communities' vulnerability. The lack of technical assistance is the most serious stressor. The lack of land and the delayed rains are the most severe stressors. Farmers' knowledge of climate change did not influence their perception of climate risks. Public climate adaptation policies should consider the local context, as well as the gender and age distributions of the public involved. [ABSTRACT FROM AUTHOR]

Fire, a prevalent land management tool in rotational shifting cultivation (RSC), has long been debated for its immediate disruption of surface soil, vegetation, and microbial communities. While low-intensity and short-duration slash-and-burn techniques are considered beneficial for overall soil function, the dual nature of fire’s impact warrants a comprehensive exploration. This review examines both the beneficial and detrimental effects of fire on soil properties within the context of RSC. We highlight that research on soil microbial composition, carbon, and nitrogen dynamics following fire events in RSC is gaining momentum. After fires, soil typically shows decreases in porosity, clay content, aggregation, and cation exchange capacity, while sand content, pH, available phosphorus, and organic nitrogen tend to increase. There remains ongoing debate regarding the effects on bulk density, silt content, electrical conductivity, organic carbon, total nitrogen, and exchangeable ions (K+, Ca2+, Mg2+). Certain bacterial diversity often increases, while fungal communities tend to decline during post-fire recovery, influenced by the soil chemical properties. Soil erosion is a major concern because fire-altered soil structures heighten erosion risks, underscoring the need for sustainable post-fire soil management strategies. Future research directions are proposed, including the use of advanced technologies like remote sensing, UAVs, and soil sensors to monitor fire impacts, as well as socio-economic studies to balance traditional practices with modern sustainability goals. This review aims to inform sustainable land management practices that balance agricultural productivity with ecological health in RSC systems.

Understanding the relationship between land-use and land-cover changes, the ecosystem services (ES) offered, and the farmers' perception about these services is essential for designing adequate strategies in the management and conservation of natural resources. Therefore, this research aims to describe the evolution of the land use and land cover, and the farmers' perceptions of ES at Diamante Negro Jutaí settlement, in the Monção municipality, Maranhão state, Eastern Amazon, Brazil. The data were collected through a mapping of use units and land cover, and 130 structured questionnaires. Farmers recognize ES as highly important for their well-being and livelihood. Food (agriculture and livestock), fish, fresh water, and lakes were perceived by farmers as highly important. Fishing, however, is the most relevant ES. In contrast, it is also the most threatened because of land-use alteration. In the period from 1995 to 2015, overall natural ground cover was reduced. Water bodies were the most highly affected with an 85 percent decrease in relation to the total area of the analysis period. The decrease in secondary forest areas (4.3 percent) and water bodies are reflections of climate change, which also has a direct impact on forms of use. Farmers' perceptions of ES can be used to formulate policies for conservation of natural resources. [ABSTRACT FROM AUTHOR]

In the northern Brazilian Amazon, indigenous peoples who inhabit the savannas of Roraima, plant their crop fields in frequently managed "forest islands" using a rotating "slash‐and‐burn" system. The system advocates long‐term sustainability, but population growth and threats to indigenous lands have led to shorter rotations and greater frequency of use of forest island areas. Our objective was to examine soil texture and fertility (0–20 cm in depth) in indigenous crop fields (roças) and fallow lands (capoeiras, secondary forests), generating recommendations that may help to optimize traditional soil management. Results indicated that roça sites are less acidic than capoeira sites, which was expected as ashes produced by burning are alkalizing, but acidity did not increase again after 8 months of cultivation, and pH was high in all sites (>6). The general increase in nutrients expected in roças compared with capoeiras did not occur. The expected decrease of soil fertility after first months of cultivation did not happen, nor the increase of soil fertility according to fallow length. Overall, soil texture proved to be the main determinant of fertility. The unexpected results suggest that the edaphic processes resulting from the traditional indigenous cultivations, practised for centuries or millennia in this region, likely contributed to the current stabilization of soil acidity and fertility. The stable moderate fertility and stable high pH observed in all sites are advantages for production in slash‐and‐burn systems in this region, and this is especially important for more pressured areas, where agroecological practices could improve soil use and management. Although not determinant for soil fertility recovery at the studied depth (0–20 cm), the fallow period (growth of capoeiras) is still important for recovery of environmental and social functions of forest islands. [ABSTRACT FROM AUTHOR]

Abstract Shifting cultivation remains an important land system in many tropical landscapes, but transitions away from shifting cultivation are increasingly common. So far, our knowledge on the social–economic and environmental drivers and consequences of such shifting cultivation transitions is incomplete, focusing on certain transitions, drivers, consequences or regions. Here, we use an archetype approach, validated through systematically identified literature, to describe eight archetypes encompassing the transitions from shifting cultivation to (1) perennial plantation crops, (2) permanent agroforestry, (3) regrown secondary forest, (4) permanent non‐perennial crops, (5) pasture, (6) wood plantation, (7) non‐cultivated non‐forested land and (8) restored secondary forest (ordered in decreasing prevalence). We then discuss social–economic and environmental factors favouring and disfavouring each archetype. This reveals that higher expected land rents, resulting from increased market access, crop price surges, secure land tenure and state interventions, are the main drivers of archetypical transitions to perennial plantation crops, permanent agroforestry, permanent non‐perennial crops and wood plantation. The prioritisation of other activities, both on‐ and off‐farm, favours transitions to regrown secondary forest and non‐cultivated non‐forested land, depending on plot‐level environmental conditions. Active forest restoration is typically implemented through state or NGO interventions. Turning to the consequences of archetypical transitions for biodiversity, the environment and livelihoods, we find that positive environmental outcomes prevail for transitions to permanent agroforestry, regrown secondary forest and restored secondary forest. Negative environmental outcomes dominate for four typically economically profitable transitions to perennial plantation crops, permanent non‐perennial crops, pasture and wood plantation. Non‐income‐related social–economic outcomes are heterogeneous within all archetypes and highly context‐dependent. Our archetype analysis shows that shifting cultivation transitions are diverse in themselves, in their drivers and their consequences. This calls for a critical and contextualised appraisal of the continuation of shifting cultivation, as well as the transition away from it, when designing land system policies that work for people and nature. Read the free Plain Language Summary for this article on the Journal blog.

Conflicts among transnational enterprises, full protection conservation units, and slash-and-burn agriculturalists have historically centered on whether this practice threatens local ecosystems. Our research in the Atlantic Forest (Southeast Brazil) was designed to identify the potential effects of slash-and-burn on soils and vegetation. We collected samples in old cropping areas that have lain fallow for 8, 15, and 60 years. We analyzed the morphological, physical, and chemical properties of the soil samples. We collected vegetation data in 10 × 10 m plots, identified tree species and calculated their basal area. Our morphological and physical data indicate that the soils are not compacted and that the aggregate stability degree increases with time. The chemical data suggest that slash-and-burn practices have not changed the pH or reduced soil fertility, while the vegetation data indicate a long-term recovery. Since our results show sustainable use of slash-and-burn cultivation we recommend land legislation should be designed to safeguard agricultural communities' livelihoods. [ABSTRACT FROM AUTHOR]

Shifting cultivation remains an important land system in many tropical landscapes, but transitions away from shifting cultivation are increasingly common. So far, our knowledge on the social–economic and environmental drivers and consequences of such shifting cultivation transitions is incomplete, focusing on certain transitions, drivers, consequences or regions.Here, we use an archetype approach, validated through systematically identified literature, to describe eight archetypes encompassing the transitions from shifting cultivation to (1) perennial plantation crops, (2) permanent agroforestry, (3) regrown secondary forest, (4) permanent non‐perennial crops, (5) pasture, (6) wood plantation, (7) non‐cultivated non‐forested land and (8) restored secondary forest (ordered in decreasing prevalence).We then discuss social–economic and environmental factors favouring and disfavouring each archetype. This reveals that higher expected land rents, resulting from increased market access, crop price surges, secure land tenure and state interventions, are the main drivers of archetypical transitions to perennial plantation crops, permanent agroforestry, permanent non‐perennial crops and wood plantation. The prioritisation of other activities, both on‐ and off‐farm, favours transitions to regrown secondary forest and non‐cultivated non‐forested land, depending on plot‐level environmental conditions. Active forest restoration is typically implemented through state or NGO interventions.Turning to the consequences of archetypical transitions for biodiversity, the environment and livelihoods, we find that positive environmental outcomes prevail for transitions to permanent agroforestry, regrown secondary forest and restored secondary forest. Negative environmental outcomes dominate for four typically economically profitable transitions to perennial plantation crops, permanent non‐perennial crops, pasture and wood plantation. Non‐income‐related social–economic outcomes are heterogeneous within all archetypes and highly context‐dependent.Our archetype analysis shows that shifting cultivation transitions are diverse in themselves, in their drivers and their consequences. This calls for a critical and contextualised appraisal of the continuation of shifting cultivation, as well as the transition away from it, when designing land system policies that work for people and nature. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Shifting cultivation is a traditional farming system that has been practised in many parts of the world for centuries. It is rampant in the northeast region of India and has widespread environmental and socio-economic impacts. The application of geospatial technology for studying the same has been slowly but surely gaining momentum. This systematic review follows the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) protocol, intending to present a comprehensive picture of remote sensing-based shifting cultivation studies in India to date, collate their findings, and identify research gaps that could be addressed using geospatial techniques. For the review, Scopus search results were refined to eliminate redundancies, and a total of 44 English language publications from peer-reviewed scientific journals were considered. The studies were apposed about their respective areas of interest, satellite data and products used, time frames, approaches, and findings. A majority of the studies are focused on mapping and monitoring shifting cultivation areas, using Landsat or IRS LISS III imagery. In the Indian context, geospatial technology can be effectively used to explore the pattern of spatio-temporal variations of shifting cultivation, disturbance and recovery cycles, secondary vegetation growth, and impacts of shifting cultivation on carbon dynamics and climate. With the availability of new sensors, data integration methods, and free algorithms/software and platforms, geospatial technology has the potential to address various aspects related to shifting cultivation. [ABSTRACT FROM AUTHOR]

Peat wildfires can burn over large areas of peatland, releasing ancient carbon and toxic gases into the atmosphere over prolonged periods. These emissions cause haze episodes of pollution and accelerate climate change. Peat wildfires are characterised by smouldering – the flameless, most persistent type of combustion. Mitigation strategies are needed in arctic, boreal, and tropical areas but are hindered by incomplete scientific understanding of smouldering. Here, we present GAMBUT, the largest and longest to-date field experiment of peat wildfires, conducted in a degraded peatland of Sumatra. Temperature, emission and spread of peat fire were continuously measured over 4–10 days and nights, and three major rainfalls. Measurements of temperature in the soil provide field experimental evidence of lethal fire severity to the biological system of the peat up to 30 cm depth. We report that the temperature of the deep smouldering is ~13% hotter than shallow layer during daytime. During night-time, both deep and shallow smouldering had the same level of temperature. The experiment was terminated by suppression with water. Comparison of rainfall with suppression confirms the existence of a critical water column height below which extinction is not possible. GAMBUT provides a unique understanding of peat wildfires at field conditions that can contribute to mitigation strategies. This paper presents the largest and longest to-date field experiment of peat wildfires. Results show peat wildfires behaviour at field conditions in term of smouldering spread, thermal severity and response to rainfall and suppression. Findings in this paper can contribute to better mitigation efforts. GAMBUT Fire Palette photograph by Wuquan Cui. [ABSTRACT FROM AUTHOR]

The evolution and transformations of swidden agriculture closely relate to ongoing studies of carbon budget, biological diversity, ecosystem services, indigenous wellbeing, and ethnic identities. Remote sensing has become an important tool to quantify and display swidden agriculture in transition. Due to its diversity, dynamics, and complexity, however, the development of universal remote sensing algorithms for mapping swidden agriculture faces major challenges. Although swidden agriculture has increasingly become the focus of climate change and other sustainable initiatives, a systematic review on remote sensing of this farming system in the tropics is seldom reported. With 89 peer-reviewed journal articles related to the identification, mapping, monitoring or forecast of swidden agriculture since the 1970s, the methodological progresses and shortcomings of remote sensing of swidden agriculture were compared and summarized, followed by providing several perspectives on near-future research directions. The conclusions were drawn as follows. Firstly, the limited remote sensing studies of swidden agriculture were mostly reported in Southeast Asia (66%), followed by Latin America and Central Africa. Secondly, Landsat is the most (59%) widely applied to monitor swidden agriculture and also holds huge potential in delineating its trajectories. Thirdly, the spectral feature-based algorithms (76%) are more used than the counterparts of geometric-based and structure-based ones. Finally, several aspects including exploring new data and algorithms for the enhancement of remote sensing of swidden agriculture have been proposed. This review paper might be served as a long-delayed appeal for strengthening remote sensing of swidden agriculture in the tropics for accurately assessing the carbon budget of forest change and other ecological and social effects caused by the evolution and transformations of swidden agriculture.

Globally, forest loss is happening because of timber harvesting, agricultural expansion, wildfires, mining extraction and service transportation networks via roads. This study was conducted during 2016 to 2019 at Ngoc Lam Commune, Thanh Chuong District, Nghe An Province, Vietnam on the effect of forest reclamation methods (FRMs), including the slash-and-burn method (SBM), the clear-cutting method (CCM), and agricultural cultivation methods on the interaction of soil physicochemical properties across the study area. To conduct this study, soil samples were collected in natural forest areas in the study area. The results indicated that the bulk density (BD) of the natural forest soils across the study area ranged from 0.86 to 1.12 g/cm³ at depths varying from 0 to 60 cm from the surface. The concentrations of total carbon (T-C), exchangeable potassium (Exch. K+ ), and exchangeable magnesium (Exch. Mg2+) in the deeper layer were normally lower than in the upper layer. Forest reclamation using the CCM influenced the increase of the BD at depths varying from 0–20 cm, but the soil texture remained same, while forest reclamation applying the CCM showed an increase in the BD in the plots depending on the land-use management (LUM). Based on these findings, LUM has a significant influence on the concentration of Exch. Ca2+, Exch. K+, Exch. Mg2+, and T-C compared to FRMs across the North-Central Vietnam. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of fire on the transformation of the soil's physical (granulometry and porosity), chemical (organic matter and pH) and mineralogical properties in an area where slash-and-burn farming predominates. The study was conducted in the district of São Pedro da Serra, municipality of Nova Friburgo, Rio de Janeiro state, Brazil, with relief formed by steep slopes interspersed with valleys. The region has a Tropical Altitude Climate, characterized by hot, rainy summers and mild, dry winters. The average annual rainfall is 1.279 mm, with the wettest months from November to March, and the driest months from May to August, marking the seasonal rainy (summer) and dry (winter) period. We collected deformed and undeformed soil samples at three depths (0-5 cm, 5-10 cm and 10-15 cm), in two areas, one that had been subject to highintensity fire (HIF) and the other where traditional slash-and-burn agriculture is practiced (S&B), with low-intensity fire. The physical, chemical and mineralogical properties of the soil had distinct responses to the disruption caused by fire of varying intensity. In the HIF area, the soil was hydrophobic, accompanied by smaller pore size (microporosity). In the S&B area, in contrast, the soil had a greater percentage of macropores. The results suggest that slash-and-burn agriculture, where there are fallow intervals, less severely affects the soil properties. [ABSTRACT FROM AUTHOR]

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 political instability.

The Congo Basin's rapidly growing population still largely depends on shifting cultivation for both energy and food security. This nexus of population growth and ecological impact will continue to exacerbate landscape degradation in the coming decades. To quantify the effects of land-use intensity on soil nutrient stocks and the functional composition of young regrowth forest in the Congo Basin, we used fallows of different ages that had been subjected to a varying number of clearing cycles. We show that repeated clearing substantially affected soil cation stocks, reducing total K, Mg and Ca in the upper 20 cm of soil by roughly 20% per clearing cycle. Additionally, we show that plant-available nitrogen (ammonium and nitrate) and phosphorus decline in the topsoil with increasing land-use intensity. Furthermore, the tree functional composition of young fallows changed after repeated clearing cycles: we observed a decrease in abundance of pioneer species and an increase in nitrogen fixing species early in succession. Variation in soil total nutrient stocks was decoupled from changes in vegetation, and soil plant-available nutrients only marginally explained tree functional composition changes. We conclude that land-use intensity substantially affects both soil total and plant-available nutrients in a shifting cultivation system, as well as the functional composition of the regenerating vegetation. However, compositional changes of the tree community are only partly driven by land-use intensity effects on soil plant-available nutrients. [ABSTRACT FROM AUTHOR]

Shifting cultivation, the oldest farming system of the world and is the dominant land use in mountainous regions of South and Southeast Asia. North-East India (NEI) region, one of the world's biodiversity hotspots, covers 17.2 million ha of land under forests, constituting ~25% of India's total forest area. The population-driven abrupt decline of the fallow period's duration has aggravated soil erosion, depletion of nutrients, decreased productivity, reduced biodiversity, and weakening of essential ecosystem services. Therefore, the present research aims to explore whether the duration of the fallow period of up to 20-years can restore diversity of tree species, biomass carbon, and ecosystem carbon stock equivalent to those under natural forests. Based on the accessibility and availability of the fallow stands, three categories were selected for the study (1–2, 5–8, and 15–20 years), and these were replicated eight times for each age group. While the 20-years of fallow increased tree diversity, it was still 22% lower than that of the natural forest. Similarly, a 2.7-fold increase in biomass carbon storage was observed with an increase in the fallow period from 5–8-years (33.4 Mg ha−1) to 15–20-years (92.9 Mg ha−1), yet the latter was 40% lower than that under the natural forests. The very labile and labile carbon stocks decreased with increase in the fallow period. In contrast, the less labile and non-labile carbon stocks increased with increase in the fallow age. Because of the absence of a long fallow management system in the region, and to minimize the risks of ecosystem carbon degradation, adopting an integrated approach is recommended to enhance the ecological integrity of the degraded lands under shifting cultivation while also improving the livelihood of the shifting cultivators.

Elucidating dynamics of soil microbial communities after disturbance is crucial for understanding ecosystem restoration and sustainability. However, despite the widespread practice of swidden agriculture in tropical forests, knowledge about microbial community succession in this system is limited. Here, amplicon sequencing was used to investigate effects of soil ages (spanning at least 60 years) after disturbance, geographic distance (from 0.1 to 10 km) and edaphic property gradients (soil pH, conductivity, C, N, P, Ca, Mg, and K), on soil bacterial and fungal communities along a chronosequence of sites representing the spontaneous succession following swidden agriculture in lowland forests in Papua New Guinea. During succession, bacterial communities (OTU level) as well as its abundant (OTU with relative abundance > 0.5%) and rare (

Elucidating dynamics of soil microbial communities after disturbance is crucial for understanding ecosystem restoration and sustainability. However, despite the widespread practice of swidden agriculture in tropical forests, knowledge about microbial community succession in this system is limited. Here, amplicon sequencing was used to investigate effects of soil ages (spanning at least 60 years) after disturbance, geographic distance (from 0.1 to 10 km) and edaphic property gradients (soil pH, conductivity, C, N, P, Ca, Mg, and K), on soil bacterial and fungal communities along a chronosequence of sites representing the spontaneous succession following swidden agriculture in lowland forests in Papua New Guinea. During succession, bacterial communities (OTU level) as well as its abundant (OTU with relative abundance > 0.5%) and rare (<0.05%) subcommunities, showed less variation but more stage-dependent patterns than those of fungi. Fungal community dynamics were significantly associated only with geographic distance, whereas bacterial community dynamics were significantly associated with edaphic factors and geographic distance. During succession, more OTUs were consistently abundant (n = 12) or rare (n = 653) for bacteria than fungi (abundant = 6, rare = 5), indicating bacteria were more tolerant than fungi to environmental gradients. Rare taxa showed higher successional dynamics than abundant taxa, and rare bacteria (mainly from Actinobacteria, Proteobacteria, Acidobacteria, and Verrucomicrobia) largely accounted for bacterial community development and niche differentiation during succession. [ABSTRACT FROM AUTHOR]

Aim: North‐eastern Madagascar is a hotspot of plant diversity, but vanilla and rice farming are driving land‐use change, including slash‐and‐burn management. It still remains unknown how land‐use change and land‐use history affect richness and composition of endemic, native and exotic herbaceous plant species. Location: North‐eastern Madagascar. Methods: We assessed herbaceous plants along a land‐use intensification gradient ranging from unburned land‐use types (i.e. old‐growth forest, forest fragment and forest‐derived vanilla agroforest) to burned land‐use types (i.e. fallow‐derived vanilla agroforest, woody fallow and herbaceous fallow) and rice paddy. We compared land‐use types and analysed the effects of land‐use history, canopy closure and landscape forest cover on species richness. Additionally, we analysed species compositional changes across land‐use types. Results: Across 80 plots, we found 355 plant species (180 native non‐endemics, 57 exotics, 60 endemics and 58 species of unknown origin). Native and exotic species richness increased with increasing land‐use intensity, whereas endemics decreased. Unburned land‐use types had higher endemic species richness (4.28 ± 0.37 [mean ± SE]) than burned ones (2.4 ± 0.21). Exotic and native species richness, but not endemics, decreased with increasing canopy closure. Increasing landscape forest cover reduced exotic, but not native or endemic richness. Species composition of old‐growth forests was unique compared to all other land uses and forest‐derived, not fallow‐derived vanilla agroforests, had a similar endemic species composition to forest fragments. Main conclusions: Our results indicate that old‐growth forests and forest fragments are indispensable for maintaining endemic herbaceous plants. We further show that the land‐use history of agroforests should be considered in conservation policy. In forest‐derived vanilla agroforests, management incentives are needed to halt loss of canopy closure, thereby maintaining or even enhancing endemics. In conclusion, considering species origin (endemic, native and exotic) and composition is essential for the identification of suitable management practices to avoid irreversible species loss. [ABSTRACT FROM AUTHOR]

Governments are increasingly committing to significant forest restoration. While carbon sequestration is a major objective, the case for restoration often includes benefits to local communities. However, the impacts of forest restoration on local hydrological services (e.g. flood and erosion risk, stream flow during dry periods) are surprisingly poorly understood. Particularly limited information is available on the impacts of passive tropical forest restoration following shifting cultivation.The outcome depends on the trade‐off between the improved soil infiltration capacity (reducing overland flow and increasing soil and groundwater recharge) and greater evapotranspiration (diminishing local water availability).Using measurements from highly instrumented plots under three vegetation types in the shifting cultivation cycle in Madagascar's eastern rainforests (forest, tree fallow and degraded abandoned agricultural land), and infiltration measurements for the same vegetation types across the landscape, we explore the impacts of forest regeneration on the ecohydrological processes that underpin locally important ecosystem services.Overland flow was minimal for the tree fallow (similar to the forest) and much lower than for the degraded land, likely leading to a lower risk of erosion and flooding compared to the degraded land. Conversely, evapotranspiration losses were lower for the tree fallow than the forest, leading to a higher net recharge, likely resulting in more streamflow between rainfall events.These results demonstrate that young regenerating tropical forest vegetation can positively contribute to locally important hydrological ecosystem services. Allowing tree fallows to recover further is unlikely to further reduce the risk of overland flow but may, at least temporarily, result in less streamflow.Synthesis and applications. Encouraging natural regeneration is increasingly seen as a cost‐effective way to deliver forest landscape restoration. Our data suggest that increasing the abundance of young secondary forest in the tropics, by increasing fallow lengths in the shifting cultivation cycle, could make a positive contribution to locally important hydrological ecosystem services (specifically reducing overland flow and therefore erosion and flooding, while maintaining streamflows). Such empirical understanding is needed to inform the models used for planning forest landscape restoration to maximize benefits to local communities. [ABSTRACT FROM AUTHOR]

This account describes the context, history and outcomes of a series of studies into the ecology of slash-and-burn (S-B) agriculture in the world's humid tropics. These studies, which began in the mid-1980s, identified promising lines of research and continued to field trials, in Central America, of candidate agricultural systems as possible sustainable alternatives to the practice. The only system to emerge from 7 years' comparative trial with any promise of sustainability, in this context, was the agroforestry technique known as alley-cropping; but only with trees of the genus Inga. Inga alley-cropping then underwent field trials with subsistence farming families in northern Honduras. The system was aimed at the twin objectives of achieving food security in basic grains, on minimal inputs, and of providing the means of eliminating further S-B in the region. Since then, Inga alley-cropping has become the heart of a sustainable and integrated rural livelihood model (the Guama Model) which is being implemented successfully in northern Honduras with some 300 families. These families had been attempting to subsist on a few hectares of land degraded by decades or centuries of S-B. The development of Inga alley-cropping, supplemented by rock phosphate and other mineral supplements, as a sustainable subsistence and cash crop alternative means that land previously being held in reserve for subsequent S-B operations can now be planted to permanent forms of agroforestry. Entire landscapes can be re-greened by productive agroforest vegetation. Achieving this at scale will require the investment of huge extension effort and funds. However, the environmental, social and economic returns are also huge; and they are sustainable. In this programme,we are seeing the vitality and goodwill of hundreds of families focussed on the raising, planting and management of trees in ways that feed the living organisms of the soil and, hence, feed themselves. In so cheerfully planting out their own futures, they plant and reshape the future of their own country. Replicating this at scale, as Rattan Lal outlines below, could reshape the future of this planet. In the mid-1980s, progress on sustainable alternatives to S-B, especially in rain forests, was frustrated by a lack of conclusiveness in the literature as to why soil fertility fails so rapidly post-burn; but also by a degree of contradiction on the impacts of the burn on certain plant nutrients. Hands (Hands 1988 The ecology of shifting cultivation. MSc thesis, University of Cambridge) concentrated on the role of soil phosphorus and attempted to resolve these contradictions. The Cambridge Alley-cropping Projects (1988–2002) continued this theme and threw light on the question of sustainable food production in rain forest environments.

Tropical forest development after slash‐and‐burn agriculture crucially affects soil carbon accumulation. However, it remains unclear how the dynamics of soil organic carbon (SOC) pools are regulated following tropical forest restoration. Our study aims to quantify the contribution of litter and soil variables to alterations in carbon pools during tropical forest restoration on slash‐and‐burn agricultural land in Xishuangbanna, Yunnan, China. This study observed a significant increase in soil carbon pools along forest restoration. The extent of the increase in labile fractions (1.9–2.5‐times) was higher than that of SOC (1.5‐times) during the restoration from early to later stages. The proportion of microbial carbon to total carbon increased from 3.0 to 7.7% during forest restoration, while those of dissolved (5.3–3.1%) and readily oxidizable (42.9–29.6%) fractions decreased. Clay content determined the accumulation dynamics of SOC (10.5%) and labile fractions (6.0–13.5%) in the later stage, while free Fe oxides (10.4–15.4%) contributed to these pools mainly in the early stage. Microbial carbon explained 22.4–26.7% and 20.6–28.3% of the variation in SOC stocks and labile fractions, respectively, whereas litter carbon accounted for 9.5–15.3% of the change in microbial carbon stock. The contribution (8.2–17.1%) of litter‐soil nutrient interactions to carbon pools increased during forest restoration. Our data suggest that carbon dynamics are mainly determined by variations in the clay content, free Fe oxides, and litter and microbial carbon, possibly through nutrient‐level interactions between the litter and soil during tropical forest restoration. [ABSTRACT FROM AUTHOR]

In northern Laos, shortened fallows in the slash-and-burn upland rice system are not sustainable either from a production or economic standpoint. This paper evaluates the potential for using the indigenous fast-growing tree, Broussonetia papyrifera L. Vent. (paper mulberry) as an economic fallow crop. The objectives of this study are to assess the inner bark yield of paper mulberry, and to evaluate rice productivity following paper mulberry cultivation. In addition, allometric models for estimating the inner bark yield of paper mulberry are developed. Inner bark yield of paper mulberry stands ranging in age from 9 to 48 months ranged from 10 to 208 g m−2, and increased with age. The models using diameter at breast height and stem height, or diameter at breast height only as independent variables explained well the variation in inner bark yield. When paper mulberry was completely removed during the rice growing season, rice yields in these areas were similar to those following weedy bush fallow. When paper mulberry was allowed to grow, rice yields were negatively correlated to paper mulberry stem density. When paper mulberry lateral branches were pruned back, rice yields could be maintained if the paper mulberry stem density was

The broad term fire culture covers a wide spectrum of practices that use fire in agrarian contexts. Gösta Berg distinguishes between svedjning and svedjebruk. The general term svedjning includes clearing woodland and bushes, for example. Svedjebruk - or swidden cultivation - is defined as "burning woodland in order to grow cereals for a short period". The technique is also called rågsvedja (from råg, the Swedish for "rye"). Swidden cultivation distinguishes between large-scale gransvedja (also called huuhtasvedja) and small-scale kaskisvedja. (Gransvedja derives from gran, the Swedish for "spruce"; kaskisvedja comes from kaske, an old Finnish word for "birch".) The huuhta technique, associated with swidden cultivation in Savolax and Karelia, was introduced by 16th- and 17th-century Finnish settlers in Swedish counties including Värmland, Hälsingland, Medelpad and Ångermanland. In parallel with this, and much earlier too, smallscale swiddening was practised across much of the Svealand and Götaland regions. The prevalence of swidden cultivation in Southern Sweden has probably been underestimated, both in terms of its scale and effects on woodland and other vegetation. Regional legislation and early cadastral maps show that swidden was carried out across Southern and Central Sweden from the Middle Ages onwards. A swidden was temporary; vegetation regenerated within a couple of years, and new plots were continually exploited. Twenty or thirty years later would see a return to the initial plot, which would be cleared and burned once more. The practice entailed a systematic, recurrent burning of outfields. In the past, one consequence of this repeated swiddening of village outfields would have been a dearth of contiguous ancient woodland in Southern and Central Sweden. A swidden yielded roughly three times that of a permanent field. Cereals from wooded and semi-wooded areas would have been produced mostly by swidden cultivation, and the technique was probably vital for agricultural production. Swiddening may have been the key to survival for small, low-yield farms before the Agrarian Revolution. However, this question needs further study, drawing on more comprehensive source materials. [ABSTRACT FROM AUTHOR]

In the city of Biguaçu, state of Santa Catarina in southern Brazil, family farmers practice a kind of natural land use in which agriculture, forestry and energy production are related. These farmers regularly practice fallow agriculture in secondary subtropical forests (Atlantic Forest biome), with production of energy in the form of charcoal. We aim at assessing the sustainability of the livelihoods of farm families through the analysis of access to assets or capital, categorized as natural, human, financial, social, physical and cultural capital, according to the approach of sustainable livelihoods. The fieldwork involved various techniques of ethnographic approach with members of 5 families of Três Riachos community, from 2012 to 2014. It is concluded that the natural capital asset access is possible in their own family property, and still be a renewable resource. As for human, physical and financial capital, it appears that in this production system, there is excessive and often unhealthy labor, using poor technologies and infrastructure. In the social capital, we emphasize the relationships of trust and reciprocity existing among farmers and external actors. Allied to this asset, there is the cultural capital, highlighting reciprocity characteristics with external agents, especially their customers. To promote the sustainability of livelihoods it is essential to facilitate full access to this capital, or increase access to those assets already established, such as the cultural capital. Thus, it is concluded that the analyzed livelihoods have the potential to be sustainable.

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Shifting cultivation involves a cycle of forest clearing, cultivation and a fallow phase. As the practice involves clearing forest, it is considered unsustainable and leads to soil fertility loss and erosion. While several variations of the practice exist, traditional communities undertake the practice systematically with relatively long fallow periods and are often knowledgeable about their landscape in terms of soil and its management. To better understand one such system, we quantified soil recovery following cultivation in terms of macronutrients and documented the traditional knowledge of the Adi community in a remote site in the Eastern Himalaya. We collected soil samples from three replicates, each from currently cultivated sites, uncut forest sites and successional sites 3, 12 and 25 yr following cultivation. Available nitrogen and phosphorus significantly increased, and there was an increasing trend in soil organic matter following cultivation. The Adi differentiated nine types of soil and preferred specific soil types for shifting and settled cultivation. We documented soil management and methods of soil fertility retention practised by the Adi. Their location of different crops in the field was based on the effect of the crop on soil fertility. Our research indicated that soil nutrient recovery was considerable following cultivation and that traditional shifting cultivators in the landscape were knowledgeable about their landscape in terms of soil diversity, undertaking practices to manage soil erosion and fertility. Future policies that will affect shifting cultivation in the region should acknowledge such systematic use of a landscape by traditional farming communities. [ABSTRACT FROM AUTHOR]

Shifting cultivation is in rapid transformation in many parts of the Global South, but the drivers and consequences of these changes are still not well understood, especially in Africa. We therefore analysed the drivers of this transformation and its impacts on livelihoods between 1995 and 2014 in two villages located in Eastern Central Tanzania by combining analysis of socio-economic and remote sensing data. Results revealed that in an upland village, the number of shifting cultivators declined from 34% to 16% and the area changed from 19% to 17%. In a plateau village, the number of shifting cultivators declined from 24% to 18% and the area substantially declined from 23% to 14%. In both villages, shifting cultivators adopted intensive land preparation methods that involved deep tillage and burying of vegetation. Transformation of shifting cultivation in the upland area was driven by adoption and enforcement of land tenure policies that restrict shifting cultivation whereas in the plateau area, it was driven by population pressure causing competition for land between shifting cultivators and pastoralists. In both villages transformation of shifting cultivation negatively affected household income and increased periods of food insecurity. [ABSTRACT FROM AUTHOR]

Certain forestry and agricultural practices are known to affect arbuscular mycorrhizal (AM) fungal communities, but the effects of deforestation – including slash-and-burn management and other more severe disturbances – in tropical rain forests are poorly understood. We addressed the effects of anthropogenic disturbance on rain-forest AM fungal communities in French Guiana, by comparing mature tropical rain forest, slash-and-burn (5 y old) and clearcut areas (8 y old). A total of 36 soil samples were collected in six plots and sequenced using a high throughput 454-pyrosequencing platform. A total of 32649 sequences from 103 AM fungal virtual taxa (VT) were recorded. Whereas alpha diversity of AM fungi did not decrease due to land-use intensification, with average richness ranging from 17 to 21 taxa per plot, beta diversity (average distance to multivariate centroid) dropped by 28% from 0.46 in rain forest to 0.33 under clearcutting. AM fungal community composition was correlated with land use and soil chemical properties. Clearcut areas were characterized by the more frequent occurrence of specialist AM fungi, compared with mature forest or slash-and-burn areas. Specifically, clearcuts contained the highest proportions of VT that were geographic (21%), habitat (31%), abundance (97%) or host (97%) specialists based on VT metadata contained in the MaarjAM database. This suggests that certain AM fungi with narrow ecological niches have traits that allow them to exploit conditions of severe disturbance. In conclusion, slash-and-burn management appears to allow diverse AM fungal communities to persist, and may favour regeneration of tropical rain forest after abandonment. More severe disturbance in the form of clearcutting resulted in marked changes in AM fungal communities. [ABSTRACT FROM AUTHOR]

Multiproxy palaeoecological evidence from a sandstone region in northern Czech Republic was collected to explore the impact of fire disturbances on the decline of the broadleaved forests during the Late Bronze Age (3250–3050 cal. BP). It has been hypothesized that human-accelerated soil leaching affected the nutrient availability in the sandstone area, thus promoting the expansion of oligotrophic-adapted plant communities in the late-Holocene. Little is known about the mechanisms which induced such large-scale vegetation transformation. We sought to determine which driving forces were involved using independent proxy records – soil and sedimentary charcoal, pollen and fungal spores. Local fire history was derived from the variation in charcoal accumulation rates (CHAR) preserved in Eustach peatbog. The fire frequency (FF) estimation over the past ~7500 years revealed distinct phases of increased burning between 3100 and 2120 cal. BP (3.0 fires 1000 yr−1) and 1400–600 cal. BP (4.3 fires 1000 yr−1). Rapid compositional changes in the pollen assemblage were documented during the Late Bronze Age period, suggesting vegetation responded to increased fire disturbances. The human influence on the fire regime is implied by the short-term increase in cereal pollen concurrent with a major fire event, indicating possible use of slash-and-burn cultivation by Late Bronze societies. This type of human subsistence strategy practised in the sandstone landscape further evolved to pastoralism as suggested by continuous presence of coprophilous fungi Sporormiella and Sordaria, which occurred since the Hallstatt/La Tène period (2750–1950 cal. BP). Our study documents, for the first time, the intentional, human-caused biomass burning from densely forested areas of Northern Bohemian sandstone region. Our results imply that increased rate of fire disturbances contributed to the Late Bronze Age transformation of broadleaved forests to oligotrophic forest communities of late-Holocene. [ABSTRACT FROM AUTHOR]

For millennia, Maya farmers (i.e., milperos) throughout Mesoamerica have managed milpa : sequential agroforests initiated by slashing and burning patches of secondary forest and then cultivating a diverse polyculture of trees and annual crops. To reduce greenhouse gas emissions associated with deforestation, the Mexican government and non-governmental organizations have urged milperos to cease burning. We collaborated with Maya milperos in several communities in the Montes Azules Biosphere Reserve region in Chiapas, Mexico to determine carbon retained as char in traditional milpas , carbon loss associated with burning, and effects of burning on soil quality. We found the carbon retention of char in Maya milpas (24 ± 6.5% of C in vegetation) is 4–1400% higher than other slash-and-burn agroecosystems reported in the literature. Burning resulted in significant carbon loss of 12.6 (±3.6) t C ha−1 yr−1, but this was partially mitigated by char production (3.0 [±0.6] t C ha−1 yr−1) and incomplete combustion of woody biomass. The effects of burning on soil were minimal, with the only significant changes observed being increases in pH, potassium availability, and cation exchange capacity (2, 100, and 7%, respectively). The mean residence times of charred materials were at least double that of uncharred biomass. While there is a risk that shortening fallow periods would undermine the sustainability of Maya swidden agroecology, proper management and secure land tenure can help maintain intensive production without enduring environmental degradation. The char produced in these swiddens and successional management could allow this agroforestry system to be a long-term carbon sink. [Display omitted] • Slash-and-burn/swidden management can be sustainable and offset carbon emissions. • Traditional Maya swiddening converts, on average, 24% of biomass carbon into char. • Maya farmers recognize the threats climate changes pose to their agroecosystems. [ABSTRACT FROM AUTHOR]

Traditional tropical agriculture often entails a form of slash-and-burn land management that may adversely affect ecosystem services such as pollination, which are required for successful crop yields. The Yucatán Peninsula of Mexico has a >4000 year history of traditional slash-and-burn agriculture, termed 'milpa'. Hot 'Habanero' chilli is a major pollinator-dependent crop that nowadays is often grown in monoculture within the milpa system., We studied 37 local farmers' chilli fields (sites) to evaluate the effects of landscape composition on bee communities. At 11 of these sites, we undertook experimental pollination treatments to quantify the pollination of chilli. We further explored the relationships between landscape composition, bee communities and pollination service provision to chilli., Bee species richness, particularly species of the family Apidae, was positively related to the amount of forest cover. Species diversity decreased with increasing proportion of crop land surrounding each sampling site. Sweat bees of the genus Lasioglossum were the most abundant bee taxon in chilli fields and, in contrast to other bee species, increased in abundance with the proportion of fallow land, gardens and pastures which are an integral part of the milpa system., There was an average pollination shortfall of 21% for chilli across all sites; yet the shortfall was unrelated to the proportion of land covered by crops. Rather, chilli pollination was positively related to the abundance of Lasioglossum bees, probably an important pollinator of chilli, as well indirectly to the proportion of fallow land, gardens and pastures that promote Lasioglossum abundance., Synthesis and applications. Current, low-intensity traditional slash-and-burn ( milpa) agriculture provides Lasioglossum spp. pollinators for successful chilli production; fallow land, gardens and pasture therefore need to be valued as important habitats for these and related ground-nesting bee species. However, the negative impact of agriculture on total bee species diversity highlights how agricultural intensification is likely to reduce pollination services to crops, including chilli. Indeed, natural forest cover is vital in tropical Yucatán to maintain a rich assemblage of bee species and the provision of pollination services for diverse crops and wild flowers. [ABSTRACT FROM AUTHOR]