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The Amazonian biome is important not only for South America but also for the entire planet, providing essential environmental services. The state of Rondônia ranks third in deforestation rates in the Brazilian Legal Amazon (BLA) political division. This study aims to evaluate the land use/land cover (LULC) changes over the past ten years (2009–2019), as well as, to predict the LULC in the next 10 years, using TerrSet 18.3 software, in the state of Rondônia, Brazil. The machine learning algorithms within the Google Earth Engine cloud-based platform employed a Random Forest classifier in image classifications. The Markov-CA deep learning algorithm predicted future LULC changes by comparing scenarios of one and three transitions. The results showed a reduction in forested areas of about 15.7% between 2009 and 2019 in the Rondônia state. According to the predictive model, by 2030, around 30% of the remaining forests will be logged, most likely converted into occupied areas. The results reinforce the importance of measures and policies integrated with investments in research and satellite monitoring to reduce deforestation in the Brazilian Amazon and ensure the continuity of the Amazonian role in halting climate change. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) remain the dominant policy to protect biodiversity and ecosystem services but have been shown to have limited impact when development interests force them to locations with lower deforestation pressure. Far less known is that such interests also cause widespread tempering, reduction, or removal of protection [i.e., PA downgrading, downsizing, and degazettement (PADDD)]. We inform responses to PADDD by proposing and testing a bargaining explanation for PADDD risks and deforestation impacts. We examine recent degazettements for hydropower development and rural settlements in the state of Rondônia in the Brazilian Amazon. Results support two hypotheses: (i) ineffective PAs (i.e., those where internal deforestation was similar to nearby rates) were more likely to be degazetted and (ii) degazettement of ineffective PAs caused limited, if any, additional deforestation. We also report on cases in which ineffective portions were upgraded. Overall our results suggest that enhancing PAs' ecological impacts enhances their legal durability. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the spatial and temporal distribution of burned areas in Rondônia State, Brazil during the years 2000 to 2011 and evaluate the burned area maps. A Linear Spectral Mixture Model (LSMM) was applied to MODIS surface reflectance images to originate the burned areas maps, which were validated with TM/Landsat 5 and ETM+/Landsat 7 images and field data acquired in August 2013. The validation presented a correlation ranging from 67% to 96% with an average value of 86%. The lower correlation values are related to the distinct spatial resolutions of the MODIS and TM/ETM+ sensors because small burn scars are not detected in MODIS images and higher spatial correlations are related to the presence of large fires, which are better identified in MODIS, increasing the accuracy of the mapping methodology. In addition, the 12-year burned area maps of Rondônia indicate that fires, as a general pattern, occur in areas that have already been converted to some land use, such as vegetal extraction, large animal livestock areas or diversified permanent crops. Furthermore, during the analyzed period, land use conversion associated with climatic events significantly influenced the occurrence of fire in Rondônia and amplified its impacts. [ABSTRACT FROM AUTHOR]

As progress is made in understanding the dynamics of land-use and land-cover change (LUCC), arguments that view population pressure as one of the major factors affecting forest destruction continue to be framed. Following the advances in the field of population-environment studies, this paper contends that a full account of the complex web of drivers involved in tropical deforestation needs to go beyond demographics per se. This paper examines the contribution of the 'population factor' as a cause of deforestation in Machadinho D'Oeste, Rondônia, Brazilian Amazonia, an area with significant small-scale farming. Conceptually, the paper shows that socioeconomic status and mediating factors (i.e., education, managerial skills, previous rural experience, integration into the local, and regional contexts), and attitudes and behaviors toward the land parcel development mediate migrants' relationships with the local environment. The analysis combines multiple data sources (i.e., demographic census, household survey, land-cover maps, in-depth interviews) and analytical approaches (i.e., fuzzy sets statistics, remote-sensing/GIS analysis, interpretivist qualitative assessment) to examine the complex interrelationships between LUCC and human population. [ABSTRACT FROM AUTHOR]

This paper operationalizes the concept of highly optimized tolerance (HOT) for the case of smallholder agriculture in Rondônia, Brazil. It seeks to understand how characteristics of family farms shift as a function of property size, arguing that as production intensifies, properties move closer to a HOT state. In this state, resources are committed to maintaining robustness against expected disturbances, such as shifts in yields or crop prices, making property more vulnerable to other unexpected disturbances, such as shifts in input prices or availability. The shifts in production, labor, and costs that occur across scale in the Ji-Paraná River Basin in Rondônia were measured using a survey instrument on a sample of farmers in the basin. Study results show decreasing production intensity with increasing property size in the sample, coupled with decreasing contracted and family labor use intensity, as well as decreased income diversification and off-farm labor. Farms smaller than 60 ha in the sample differed markedly in production and cost structure from those that were larger. For these smaller properties, meeting the requirements of Rondônia's new environmental licensing program (LAPRO) may lead to an increase in the sale of land parcels to cover debts and a speeding up of land consolidation in the region. [ABSTRACT FROM AUTHOR]

Agricultural development and climate change will be two of the major stressors on the Amazon natural-human system in the decades to come. Environmental licensing for rural properties is being implemented in several states in the Brazilian Amazon with the goal of restoring forests in agricultural landscapes and mediating the impacts of these stressors. This study presents an agent-based model of ranching and land exchange, informs it with empirical results from social research in the Ji-Paraná River Basin, Rondônia, Brazil, and investigates the social, economic, and environmental outcomes that can be expected as a result of environmental licensing in the context of climate change. Model results informed by these data suggest that although an environmental licensing scheme with monitoring and enforcement may increase the level of forested land in ranching landscapes, it may do so at the expense of the small producer. To the extent that effective monitoring and enforcement exist, a focus on larger holdings will help to mediate this negative social impact. These results suggest that a middle ground can be found in cases where current environmental goals conflict with legacies of past colonization and resource-use regimes. [ABSTRACT FROM AUTHOR]

Abstract: A Teflon® dynamic flux chamber was used to characterize Gaseous Elemental Mercury (GEM) flux from forested and open field soils in a highly changing environment in Rondônia State, western Amazon. We simultaneously analyzed meteorological parameters at the soil level relating GEM fluxes to soil temperature, air humidity, soil moisture, solar radiation, and speed and wind direction. We also examined variations of atmospheric GEM concentration. GEM fluxes during the day and night in the open field site were significantly different (17±14ngm−2 h−1 and 0.9±1.9ngm−2 h−1, for day and night, respectively), but were similar within the forest site (4.8±1.4ngm−2 h−1 and 4.4±1.8ngm−2 h−1 for day and night periods, respectively). A comparison between 24-h periods averages in the two sites showed much larger emission from the open field site. GEM fluxes at the open field site were positively correlated with soil moisture, solar irradiation and soil temperature and inversely correlated with air humidity. At the forest site GEM fluxes showed no correlation with meteorological variables. At the open field site GEM concentrations significantly correlated with GEM flux, at least during the day. At night in the open field site and during the day and night at the forest site no correlation was found between GEM fluxes and GEM concentrations in the ambient air. Higher emissions from the open field site support earlier studies showing larger Hg remobilization following forest conversion to pasture. [Copyright &y& Elsevier]