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Indigenous peoples and local communities are key actors in the preservation of important biodiversity resources around the world. However, the ever-encroaching agricultural frontier and expansion of conventional agricultural practices threaten these communities, their autonomy over the land, and the traditional knowledge and practices associated with biodiverse ecosystems. Agroecology emerges as an important solution to support the continuation of agrobiodiversity, food security, and environmental conservation, but top-down solutions often do not resonate with the lived realities of traditional, Indigenous, and small-scale farming communities. This paper examines a collaborative research and narrative network developed over the past several years around traditional erva-mate agroforestry production in Southern Paraná, Brazil. It offers an example of how oral environmental history and public history can support conservation practices through agroecology. The key outcomes of this interdisciplinary, multi-dimensional research and engagement were the development of a candidacy for the system to be recognized as a Globally Important Agricultural Heritage System (GIAHS) from the Food and Agricultural Organization of the United Nations (FAO) and the implementation of a Dynamic Conservation Action Plan to address the threats and challenges farmers and communities are facing. The discussion explores two concepts that were integral to these processes, the creation of narrative networks and a focus on plurivocity. Both approaches ensured that the actions, knowledge, and narratives developed through the GIAHS candidacy were not imposed but agreed upon and generative through narrative and dialogue, remaining true to the realities and lived experiences of community members. [ABSTRACT FROM AUTHOR]

Tropical climate-smart agriculture could be a cost-effective and scalable nature-based solution toward achieving net-zero greenhouse gas (GHG) emissions in the coming decades. Nevertheless, the lack of integrated on-farm CO 2 , CH 4 , and N 2 O flux measurements remains a barrier to including these systems in certification programs and the carbon (C) market. This systematic literature review critically examines field-measured GHG emission studies within climate-smart agri-systems in Brazil, aiming to: (i) integrate GHG-measured data, (ii) explore geographical representativeness and connections between organizations and authors, (iii) analyze distributions of studied GHG molecules, climate-smart system types, and productive components, (iv) conduct a meta-analysis on the adoption of climate-smart agriculture, and (v) identify methodological and scope gaps, providing insights for future research directions. The systems considered include no-till, well-managed pasture, integrated crop-livestock, and integration with trees (i.e., crop-forestry, livestock-forestry, crop-livestock-forestry, and multistrata agroforestry). Out of 1200 papers mentioning GHGs and climate-smart systems, 74 contained reliable on-farm flux measurements. Most authors were Brazilians affiliated with Embrapa and public Universities. Studies concentrated on the Atlantic Forest and Cerrado, with scarce data for other biomes. Over half of the trials assessed individual GHG molecules and only one climate-smart system. Urochloa spp. and Avena spp. were the most studied forage genera, while soybeans and corn dominated annual crops. Eucalyptus spp. and beef cattle were common trees and animals. No-till, integrated crop-livestock, and agricultural integrations involving trees showed soil C–CH 4 influx from 0.8 to 1.0 kg ha−1 y−1. Transitioning from pasture monoculture to integrated systems decreased N–N 2 O emissions by up to 1.63 kg ha−1 y−1. Converting extensive grazed land to intensified-integrated systems reduced animal CH 4 intensity, with cuts of up to 122 g CH 4 per kg of average daily weight gain. Future research must urgently address methodological issues, such as de-standardization (e.g., 8–10 flux units found per GHG molecule) and the absence of crucial ancillary variables. In conclusion, adopting diversified climate-smart agri-systems shows potential to mitigate GHG emissions, but caution is advised when extrapolating our numerical findings due to limited data across Brazilian edaphoclimatic conditions. We urge scientists to prioritize frequent on-farm measurements of all three GHGs (CO 2 , N 2 O, and CH 4) along with agroecosystem C sequestration across multiple climate-smart systems, enabling reliable and comparable net GHG flux calculations to identify the most sustainable option. Advancing and standardizing GHG measurements in Brazil offer an opportunity to enhance GHGs inventory accuracy, calibrate models, and promote policies and investments that expand refined tropical climate-smart agriculture. [Display omitted] • We systematically reviewed GHG measurements in Brazilian climate-smart agri-systems. • Well-managed pastures, no-till, and integration-based systems mitigate GHG emissions. • Brazilian GHG dataset incompletely represents systems and environmental complexities. • Producing agri-GHG field data is still vital for policies, investments, and C market. • Future GHG research should standardize flux units and include ancillary variables. [ABSTRACT FROM AUTHOR]

The environmental changes in the Caatinga biome have already resulted in it reaching levels of approximately 50% of its original vegetation, making it the third most degraded biome in Brazil, due to inadequate grazing practices that are driven by the difficulty of monitoring and estimating the yield parameters of forage plants, especially in agroforestry systems (AFS) in this biome. This study aimed to compare the predictive ability of different indexes with regard to the biomass and leaf area index of forage crops (bushveld signal grass and buffel grass) in AFS in the Caatinga biome and to evaluate the influence of removing system components on model performance. The normalized green red difference index (NGRDI) and the visible atmospherically resistant index (VARI) showed higher correlations (p < 0.05) with the variables. In addition, removing trees from the orthomosaics was the approach that most favored the correlation values. The models based on classification and regression trees (CARTs) showed lower RMSE values, presenting values of 3020.86, 1201.75, and 0.20 for FB, DB, and LAI, respectively, as well as higher CCC values (0.94). Using NGRDI and VARI, removing trees from the images, and using CART are recommended in estimating biomass and leaf area index in agroforestry systems in the Caatinga biome. [ABSTRACT FROM AUTHOR]

Soils are a source of natural capital that provide and regulate a range of ecosystem services (ES) and play an important role in sustaining human welfare. Nonetheless, the quality and quantity of soil ecosystem services (SES) delivery over the long term depend on the use of sustainable land management practices. In the present study, we assessed seven SES using a set of soil quality indicators in four production systems based on yerba mate (Ilex paraguariensis A. St.-Hil) in the Araucaria Forest biome of Southern Brazil: two sites were under traditional agroecological agroforestry management, one was a silvopastoral system with dairy pasture, and the last one was a monoculture yerba mate production system. The SES measured were soil fertility, carbon sequestration, erosion control, nutrient cycling, plant provision, biodiversity, and health. Soil samples were collected at various depths and analysed for chemical, physical, and biological attributes. A principal component analysis on the dataset showed that the soil quality indicators that best represent the variance between the systems at the 0–10 cm layer were acidity, microbial activity (FDA), total nitrogen, (TN), structural stability index (SSI), cation exchange capacity (CEC), pH, sum of bases (SB), microbial quotient (qMic), density of earthworms (EwD), bulk density (BD), and carbon stocks (Cstock). Soil quality indicators ranging from 0 to 1 were used to graphically represent the set of SES. The indicator-based approach used to explain the differences among the four production systems was able to capture the soil functions and offered a good starting point for quantifying SES provision. [ABSTRACT FROM AUTHOR]

The growth of forestry, mainly eucalyptus, driven by the industry demand for pulp and paper, has significantly changed the landscape around the globe. The so-called agroforestry systems have the advantage of reducing pressure on native forests in different regions of the world. However, this practice can bring impacts to the environment, and contribute to the intensification of agrarian conflicts. The aim of this research is to expose the intrinsic relationship between the dynamic of the forestry expansion in the São Paulo area of the Paraíba Valley, one of the largest agro-producing regions in Brazil, and the regional socioeconomical structure. These results may support further studies in order to define the possibilities and limitations of this type of economic use. With the use of remote sensing techniques using Landsat satellite images, we measured the areas planted with eucalyptus in the study area (Paraíba Valley) between 1986 and 2010. This area was pioneer in this kind of forestry and still is one of the largest producers while still expanding. In the period studied, among positive and negative variations, the planted area increased from approximately 55,000 ha in 1986 to more than 60,000 ha in 2010. This change was driven by industrial demand, as shown by the IBGE data. [ABSTRACT FROM AUTHOR]

This review aimed to provide a critical and systematic evaluation of the scientific literature about the effect of tree arrangements of the silvopasture system on the thermal environment, behaviour, and performance of cattle. We conducted a search using Web of Science and Google Scholar to identify the key literature of the theme. Peer-reviewed published articles written in English, comparing one or more tree arrangements of SPS to treeless pasture or comparing shaded and sunny areas within the SPS, were selected. The resulting manuscripts (n=191) underwent a four-step PRISMA appraisal process. This process resulted in a final sample of 37 articles, which were used for recording metadata, bibliometric analysis, and assessment of the results, using the software R. Of the 37 articles, 20 studies evaluated dairy cattle (behaviour: 14; performance: 7) and 17 evaluated beef cattle (behaviour: 6; performance: 12). The main behaviours evaluated were grazing (95%) and ruminating (90%), while weight gain (89%) was the main performance variable evaluated. The cooccurrence network analysis highlighted that the studies related the animals' response to improving the thermal environment promoted by silvopasture systems. The main difference among tree arrangements evaluated by the studies was tree density, which ranged from 5 to 800 trees/ha; most studies covered SPS with row of trees (single row, n=16 and multiple rows, n=19). Most studies (n=32) were carried out in Brazil. The evidence of this review showed that regardless of tree arrangement, the silvopasture system improves the thermal environment for cattle, although some effects on behaviour and performance are inconclusive. [ABSTRACT FROM AUTHOR]

Climate change is one of the main drivers of species extinction in the twentyfirst-century. Here, we (1) quantify potential changes in species' bioclimatic area of habitat (BAH) of 135 native potential agroforestry species from the Brazilian flora, using two different climate change scenarios (SSP2-4.5 and SSP5-8.5) and dispersal scenarios, where species have no ability to disperse and reach new areas (non-dispersal) and where species can migrate within the estimated BAH (full dispersal) for 2041–2060 and 2061–2080. We then (2) assess the preliminary conservation status of each species based on IUCN criteria. Current and future potential habitats for species were predicted using MaxEnt, a machine-learning algorithm used to estimate species' probability distribution. Future climate is predicted to trigger a mean decline in BAH between 38.5–56.3% under the non-dispersal scenario and between 22.3–41.9% under the full dispersal scenario for 135 native potential agroforestry species. Additionally, we found that only 4.3% of the studied species could be threatened under the IUCN Red List criteria B1 and B2. However, when considering the predicted quantitative habitat loss due to climate change (A3c criterion) the percentages increased between 68.8–84.4% under the non-dispersal scenario and between 40.7–64.4% under the full dispersal scenario. To lessen such threats, we argue that encouraging the use of these species in rural and peri-urban agroecosystems are promising, complementary strategies for their long-term conservation. [ABSTRACT FROM AUTHOR]

Soil quality is its ability to function within the limits of the ecosystem and land use to ensure biological productivity, preserve environmental quality, and promote plant and animal health. Thus, the objective of this study was to select soil quality indicators sensitive to different agricultural practices adopted in areas of agroecological systems in the Cerrado of Minas Gerais, Brazil. Soil samples were collected in the 0-20 cm layer, at the end of the dry season, in three different rural properties dedicated to an agroecological system (AS) located in the municipalities of Romaria and Uberlândia, Minas Gerais, Brazil. Ten soil samples were evaluated, five from areas with agroecological management and five from pasture areas as reference. Chemical attributes, microbiota population, microbial biomass carbon (MBC), soil basal respiration (SBR), and activity of beta-glucosidase, phosphatase, and arylsulfatase enzymes were evaluated. The variables basal respiration, betaglucosidase, pH, and bacterial and actinobacterial colonies were sensitive to different agroecological (AS) and pasture managements, so these variables can be used as indicators of soil quality. The mean values between the ratio of AS and pasture of these indicators were 1.69, 1.20, 3.57 and 2.44, respectively. Agroecological system areas showed a soil with better quality and, possibly, greater activity of its basic functions. [ABSTRACT FROM AUTHOR]

Pyrolysis is a promising technology for thermal conversion of lignocellulosic biomasses into a higher added value fuel. The aim of this study was to analyze the potential of four agroforestry biomasses to produce energy as a raw material or as a bio-coal. In this study, slow pyrolysis was conducted in three final temperatures to evaluate the bio-coal production of four agroforestry biomasses widely available in Brazil. The biomasses used were sugarcane bagasse (Saccharum sp.), bamboo (Dendrocalamus giganteus), straw bean (Phaseolus vulgaris) and eucalypts wood chips (Eucalyptus sp.). In the first part was presented the raw biomasses proprieties, such as lignin, carbon, hydrogen and ash contents. In the second part was showed the bio-coal proprieties, such as gravimetric and fixed carbon yields, fixed carbon and ash contents. These bio-coal results were showed as a function of final temperature of pyrolysis. The best energy indicators for bio-coal production, such as fixed carbon yield, high heating value, was observed in the bamboo and eucalypts. The bagasse and straw bean biomasses have high concentrations of ash and low lignin content when compared with the other biomasses assessed and are less suitable to produce bio-coal. [ABSTRACT FROM AUTHOR]