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Tropical forests harbor a significant portion of global biodiversity and are a critical component of the climate system. Reducing deforestation and forest degradation contributes to global climate-change mitigation efforts, yet emissions and removals from forest dynamics are still poorly quantified. We reviewed the main challenges to estimate changes in carbon stocks and biodiversity due to degradation and recovery of tropical forests, focusing on three main areas: (1) the combination of field surveys and remote sensing; (2) evaluation of biodiversity and carbon values under a unified strategy; and (3) research efforts needed to understand and quantify forest degradation and recovery. The improvement of models and estimates of changes of forest carbon can foster process-oriented monitoring of forest dynamics, including different variables and using spatially explicit algorithms that account for regional and local differences, such as variation in climate, soil, nutrient content, topography, biodiversity, disturbance history, recovery pathways, and socioeconomic factors. Generating the data for these models requires affordable large-scale remote-sensing tools associated with a robust network of field plots that can generate spatially explicit information on a range of variables through time. By combining ecosystem models, multiscale remote sensing, and networks of field plots, we will be able to evaluate forest degradation and recovery and their interactions with biodiversity and carbon cycling. Improving monitoring strategies will allow a better understanding of the role of forest dynamics in climate-change mitigation, adaptation, and carbon cycle feedbacks, thereby reducing uncertainties in models of the key processes in the carbon cycle, including their impacts on biodiversity, which are fundamental to support forest governance policies, such as Reducing Emissions from Deforestation and Forest Degradation.

The Brazilian semi-arid region is characterized by low and erratic rainfall, high temperatures and high potential evapotranspiration. The removal of firewood from the native tropical dry forest, called Caatinga, can negatively impact important ecosystem services, such as soil conservation, water resources, biodiversity and atmospheric carbon capture, if performed in an unsustainable manner. Most global climate models indicate that Caatinga will experience temperature increases and rainfall decreases in the next few decades. We used the Century model to simulate the impact of climate changes on woody vegetation growth and on vegetation and soil organic carbon stocks in a Caatinga area managed with a single clear cut or cuts every 10 years, 15 years, and 20 years, followed or not followed by the burning of plant residues (leaves and small branches) left after firewood removal. The effects of future climate projections, (LOW, MIDI and HIGH members of the climate scenario SRES A1B, which corresponded to different CO2 emission predictions, downscaled by the Eta/CPTEC model), were compared to those of the projection of the historical climate. With the current climate, it would take 50 years to regenerate the Caatinga biomass stock to a level close to that before cutting after a single cut, followed or not followed by fire. Therefore, the recommended cutting cycles (1020 years) were not long enough to allow for the regeneration of a fully mature Caatinga. However, all of these cycles reached sustainable biomass production levels, with similar total productions until the end of the century. Under these conditions, the lower proportions of biomass recovery of shorter cycles would be compensated by more frequent cutting. The model also indicated that burning or not burning the residues would have little effect. On the contrary, if the climate changes as predicted, the biomass of the native Caatinga vegetation and soil organic carbon stock would decrease throughout this century, even without cutting the vegetation. All of the cutting cycles would not provide sustainable firewood production, with reduced production after each consecutive cut. Therefore, if the climate changes as expected, forest management legislation should require longer periods of forest recovery between cutting cycles for sites with environmental conditions (e.g., climate, soil and vegetation) similar to those of the present study.

This study evaluates the simulations of the Noah-MP surface processes over a crop and a forest sites in Amazonia using tower observations. Soil moisture simulations agree with the observations in both land covers, mainly during the rainy season. However, simulations show cold biases in the soil temperature at both sites. The magnitude and seasonal cycle of the surface energy fluxes are better simulated at the crop site, although the model significantly underestimates the sensible heat flux at this site. The model reproduces the seasonal pattern of surface runoff at both sites. The Noah-MP model does not adequately simulate the base flow at the crop site, while the simulated total runoff at the forest site is closer to the observation than at the crop site. The results show that, in general, the Noah-MP model simulations for the two sites in Amazonia exhibit fairly realistic performance, particularly over the crop site. However, there are cold biases in soil temperature simulations, which could be related with the parameterization of the equilibrium relationship between soil moisture and soil temperature.

The progress in solar energy resource assessment for Chile is reported, including measurements from a ground station network spanning more than three years of data, satellite estimations from the recently developed Chile-SR model including three full years of data, and simulations that evaluate the potential for solar thermal, photovoltaics (PV) and concentrated solar power (CSP) utilization.The satellite estimation model adapts the Brasil-SR methodology with the combined use of visible and infrared (IR) satellite images, an enhanced treatment for altitude-corrected meteorological variables and an effective cloud cover computations that allows the estimation of the global horizontal and diffuse horizontal irradiation on an hourly basis. Direct normal irradiation (DNI) is computed from the direct horizontal irradiation by applying the Boland-Ridley-Laurent (BRL) model of diffuse fraction and proper solar geometry corrections. Comparison of the satellite-derived data with the ground station data shows good agreement and low error levels thus served for model validation. The results indicate that Chile is endowed with one of the highest levels of solar resource in the world in terms of annual irradiation for large portions of its territory. There is a small decrease in yearly levels of GHI and DNI with latitude that in practice indicate that most of the country shares exceptional conditions for solar energy. However, coastal regions have a large decrease in both GHI and DNI due to the persistence of seasonal cloud covers with daily cycles.The use of irradiation data from the Chile-SR model for system simulation indicates that solar fractions over 80% are achievable for residential-sized solar thermal systems in most of the country, with PV systems yielding between 4.5 and 8. kW. h/kWpv, and CSP annual yields of up to 240. GW. h/year for a 50. MW parabolic trough plant. These results indicate that the country has the potential for ample utilization of solar energy conversion technologies in most of its territory when considering annual GHI and DNI, suitable terrain availability and energy (electricity and heat) demand from industrial, commercial and residential activities.

The question of how smallholders of the Amazon estuary, locally known as cabolcos, have adapted their land use systems to produce resources during booms and busts is analyzed in this article. We draw upon more than 50 years of census data and more than 30 years of remotely sensed land-cover data to reconstruct these dynamics from World War II to the present. We found that smallholders are highly flexible in their land use decisions and livelihood strategies and that such flexibility has helped them to adapt their land-use systems to produce resources in demand during market booms and conserve forests. Smallholder mosaic landscapes contain forest fragments that enhance socioecological resilience to floods and other events produced by changes in the local hydro-climatic regimes due to sea-level rise and other climate-related changes. We argue that flexibility is a tool to reduce livelihood vulnerability by facilitating adaptation to global market and climate driven changes over the long term.

The results of an ensemble of regional climate model (RCM) simulations over South America are presented. This is the first coordinated exercise of regional climate modelling studies over the continent, as part of the CLARIS-LPB EU FP7 project. The results of different future periods, with the main focus on (20712100) is shown, when forced by several global climate models, all using the A1B greenhouse gases emissions scenario. The analysis is focused on the mean climate conditions for both temperature and precipitation. The common climate change signals show an overall increase of temperature for all the seasons and regions, generally larger for the austral winter season. Future climate shows a precipitation decrease over the tropical region, and an increase over the subtropical areas. These climate change signals arise independently of the driving global model and the RCM. The internal variability of the driving global models introduces a very small level of uncertainty, compared with that due to the choice of the driving model and the RCM. Moreover, the level of uncertainty is larger for longer horizon projections for both temperature and precipitation. The uncertainty in the temperature changes is larger for the subtropical than for the tropical ones. The current analysis allows identification of the common climate change signals and their associated uncertainties for several subregions within the South American continent.

The generation of municipal solid waste (MSW) has increased over time in Brazil, along with changes in waste quality, which gives rise to discussions regarding the importance of properly managing and disposing of these wastes. Currently, issues involving the management of MSW have a central focus in carrying out public policies. Effective implementation of the National Solid Waste Policy (NSWP) – Law nº. 12,305/2010 is expected to bring changes in the panorama of solid waste in Brazil. This work is a review of literature that aims to address some aspects of the MSW in Brazil, considering some changes expected to occur in the public sector after NSWP implementation. Some data is presented and discussed in order to foster an understanding of the evolution of MSW management in Brazil and to highlight challenges for the NSWP compliance with regulation, such as the expansion of the collection and treatment of MSW, more active societal involvement in waste-separation processes and the difficulty of eradicating open dumps and replacing them with landfills. In general, while there were improvements in MSW management, they were insufficient to address the changes proposed by the NSWP in order to establish integrated MSW management that would be effective and sustainable for both the environment and society. This indicates the need for urgent change in the structure of the MSW sector in Brazil.

In recent years, discussions regarding scenarios methods for the Brazilian Amazon have been mostly explored from the sole perspective of deforestation concerns. This paper proposes an original approach using participatory scenarios as a method that may be able to put in perspective, at different levels of decision-making, a specific action of territorial planning in Pará State, Brazil. The method allows the dialogue between stakeholder representatives, government organizations and communities involved in that territorial process. The scenarios produced substantial and sometimes contradictory data: while they can be considered as a way of empowerment for the local communities, participatory scenarios also have their limits and may reveal structural forms of authority or domination within the project-promoting institutions and local communities. The information collected allows scientists of various areas (Modeling, Social Sciences), community leaders and managers to elaborate a reflection upon the levers that may condition the implementation of effective actions and public policies in territorial units.

Understanding to what extent different land uses influence fire occurrence in the Amazonian forest is particularly relevant for its conservation. We evaluate the relationship between forest fires and different anthropogenic activities linked to a variety of land uses in the Brazilian states of Mato Grosso, Pará, and Rondônia. We combine the new high-resolution (30 m) TerraClass land use database with Moderate Resolution Imaging Spectroradiometer burned area data for 2008 and the extreme dry year of 2010. Excluding the non-forest class, most of the burned area was found in pastures, primary and secondary forests, and agricultural lands across all three states, while only around 1% of the total was located in deforested areas. The trend in burned area did not follow the declining deforestation rates from 2001 to 2010, and the spatial overlap between deforested and burned areas was only 8% on average. This supports the claim of deforestation being disconnected from burning since 2005. Forest degradation showed an even lower correlation with burned area. We found that fires used in managing pastoral and agricultural lands that escape into the neighboring forests largely contribute to forest fires. Such escaping fires are responsible for up to 52% of the burned forest edges adjacent to burned pastures and up to 22% of the burned forest edges adjacent to burned agricultural fields, respectively. Our findings call for the development of control and monitoring plans to prevent fires from escaping from managed lands into forests to support effective land use and ecosystem management.

Regiões de transição como a Amazônia e Cerrado são fundamentais para a compreensão da influência de variáveis ambientais na distribuição dos principais tipos de vegetação que compõem os diferentes biomas ao longo do tempo. O objetivo geral do trabalho foi analisar a dinâmica sazonal da vegetação por meio de dados de sensoriamento remoto, caracterizando os estratos de vegetação neste ecótono e sua relação com fator ambiental, tal como precipitação na região de transição Amazônia-Cerrado. Foram distribuídas 20 amostras, contendo 100 pixels cada uma, ao longo do ecótono Amazônia-Cerrado, dentro de unidades de conservação, onde através do índice de vegetação (EVI) do produto MOD13A2 (resolução espacial de 1Km) e da precipitação do produto 3B43 (TRMM), para o período de 2000 a 2013, foram analisadas a sazonalidade e dinâmica temporal da vegetação e precipitação. Com ajustes realizados no software TIMESAT para a série temporal, foram extraídas para as 20 amostras as métricas máximo, amplitude e integral-L, na qual através da métrica máximo do índice de vegetação, por meio de cálculos para definição dos limiares anuais, foi feita a estratificação da vegetação em três grupos. Foram realizadas também análises de correlações e de agrupamento entre os grupos. A vegetação e a precipitação nas 20 amostras apresentaram forte correlação entre os valores de máximo (0,86). Entre os três grupos, o valor da mediana da métrica amplitude, que indica o grau de sazonalidade, foi maior no grupo 1, com 1889,7, e oscilou pouco entre os grupos 2 e 3, com valores 1526,6 e 1543,8, respectivamente. A métrica integral-L, que mede o acumulado do índice de vegetação nos ciclos de crescimento, teve valores de medianas relativamente aproximados nos grupos 1 (86808) e 2 (83379,2), e no grupo 3 os valores mais baixos (57655,6). As anomalias interanuais entre os três grupos e métricas analisadas mostrou-se com alto grau de variabilidade, sendo que apenas alguns anos estiveram contidos dentro da faixa de variação normal (5% positivo e negativo). As análises de correlações entre as métricas analisadas (máximo, amplitude e integral-L) e entre os anos (ciclos de crescimento), indicam que os grupos são bem heterogêneos e que não apresentam uma relação linear entre as variáveis, onde foi observado que o grupo 3 teve uma correlação negativa significativa entre a amplitude e máximo, e uma correlação positiva significativa entre máximo e integral ao longo dos ciclos. De acordo com os resultados analisados no trabalho, a vegetação na região de transição Amazônia-Cerrado mostrou uma grande heterogeneidade (variabilidade) em sua composição.