Brazil is a powerhouse in terms of water resources, which are instrumental to the country’s transition to sustainability. However, to realize this potential, substantial management and conservation ...hurdles must first be overcome. We propose a novel strategy for the use, management, and conservation of Brazilian water resources. Our approach recognizes the spatial heterogeneity of water abundance and is based on a multisectoral perspective, including energy, food, sanitation, and environmental conservation. The main recommendations are to adopt low-cost local and subnational solutions and to design policy mixes, both based on the logic of the nexus water-food-energy-ecosystem. We offer as examples programs that 1) increase cistern infrastructure in drylands, 2) use constructed wetlands to improve sewage treatment in small cities and vulnerable areas, 3) turn the focus of conservation to aquatic ecosystems, 4) stimulate the adoption of small hydrokinetic turbines for energy generation in sparsely populated river-abundant regions, such as the Amazon Region, 5) diversify the matrix of renewable energy sources by combining hydropower with biomass and wind energy generation, and 6) mixes policies by integrating multiple sectors to improve regulation, use and management of water resources, such as the Brazilian “Water for All” Program. By following these recommendations, Brazil would align itself with the goals established in international agreements and would turn its abundance of water resources into development opportunities.
Dietary guidelines urge Brazilians to increase their consumption of raw vegetables. Yet key issues must be tackled by the government and civil society, not only to foster consumers’ appetite for ...healthier food, but more importantly to diminish the gaps between local demand and production, determined by food and land accessibility. We examine whether vegetable production in Brazil meets the demand to provide Brazilians the daily amount of fresh food recommended by the World Health Organization (WHO). We developed demand scenarios in Brazil for 2008 and 2030, based on demand density maps built at the district level using production census surveys, household acquisition data, and population growth estimates. Results reveal an inherent inequality in vegetable consumption between the southern and central northern regions of Brazil that follows food insecurity regional indicators. Even in more urbanized regions and metropolitan areas, where the best balance between vegetable production and acquisition is found, simulated demand is far from WHO recommendations. A complementary discussion regarding land distribution and fresh food production supports our outlook on the weaknesses of existing rural policies for land reform and sustainable local fresh food production that directly affect demand and nutritional security. This work was the foundation to the Delivering Food Security on Limited Land (DEVIL) project in Brazil supported by Belmont Forum consortium.
We provide a synthesis of what regional scientific research networks in less developed regions of the world can do and why they might be relevant for societal decisions and practice. We do so through ...a focus on three regional science network initiatives that aim to enhance understanding of the multiscalar dynamics of global environmental change (GEC) regionally and globally, namely the Southern Africa Regional Science Initiative (SAFARI 2000), the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), and the Inter-American Institute for Global Change (IAI). With a view to aiding future efforts at regional research network formation, we assess whether and how these three networks enhanced regional science, and the extent to which they sought and managed to bridge the science-policy gap that challenges GEC science as a whole. Identifying key decisions and attributes bearing on their successes, the analysis attends specifically to how the three networks sought to build capacity, how differences and similarities between them affected their level of autonomy from governments, and how this and other factors influenced their functioning and achievements.
Abstract
Carbon flux of Amazonian primary forest vegetation has been shown to vary both spatially and temporally. Process-based models are adequate tools to understand the basis of such variation and ...can also provide projections to future scenarios. The parameterization of such process-based models requires information from the vegetation in question simply because ecosystem-level gas exchange is a direct result of the tightly coupled interaction between local vegetation and regional climate. In this study, data are presented concerning canopy structure leaf area index (LAI), and the ratio of leaf dry mass to leaf area (LMA), leaf chemistry area-based foliar nitrogen content (Narea) and carbon isotope composition (δ13C), and photosynthetic gas exchange maximum carbon assimilation rates (Amax), stomatal conductance (gs@Amax), maximum carboxylation capacity (Vcmax), and respiration rates (Rd) versus relative height from an extensive survey of primary forest vegetation of the Santarém region (eastern Amazon, Santarém, Federal State of Pará, Brazil). Ground-level LAI values ranged between 4.5 and 5.9. Both Amax and Vcmax showed large variations within the canopy profile with values ranging between 2.4 and 15.7 μmol m−2 s−1 and between 10.1 and 105.7 μmol m−2 s−1, respectively. Also, Narea varied between 0.75 to 4.19 gN m−2, and similar to Amax and Vcmax, showed higher values at the top of the canopy. Variations were detected among sites in patterns of vertical distribution of Narea and LAI, indicating spatial heterogeneity of the forest. Also, no statistically significant evidence of seasonal variations on parameters was observed, indicating that there is limited gas exchange acclimation by the vegetation to wet or dry seasons.
Sparkling wines have become a popular beverage in recent years, and the production of these wines is subject to adulteration during fermentation. This study investigated the stable carbon isotopic ...composition (expressed as δ13C) of the wine and of the CO2 bubbles produced during the second fermentation for a number of sparkling wines produced in different countries around the world. Carbon isotope ratio analyses were used to estimate the addition of sugar obtained from C4 plants (sugar cane or corn). The average δ13C values of the Brazilian brut, demi-sec, and doux sparkling wines were −20.5 ± 1.2‰ (n = 18), −18.1 ± 1.3‰ (n = 9), and −15.8‰ (n = 1), respectively. These values were statistically heavier (more positive carbon isotope ratio values) than the average δ13C of sparkling wines produced in other parts of South America (Argentina and Chile, −26.1 ± 1.6‰, n = 5) and Europe (France, Germany, Italy, Portugal, and Spain, −25.5 ± 1.2‰, n = 12), but not statistically different from sparkling wines produced in the United States or Australia. The most likely explanation for differences in the carbon isotope ratios of wines from these different regions is the addition of C4 sugar during the production of some sparkling wines from Australia, Brazil, and the United States. The isotopic composition of the CO2 bubbles (δ13C-CO2) followed similar trends. The average δ13C-CO2 of most of the Brazilian and Argentine sparkling wines was −10.8 ± 1.2‰ (n = 23), indicating that the likely source of carbon for the second fermentation was sugar cane. Conversely, the average δ13C-CO2 of most of the sparkling wines produced in Chile and Europe was −22.0 ± 1.2‰ (n = 13), suggesting that a different sugar (most likely sugar beet) was most used in the second fermentation. It was concluded that in many cases, the carbon isotope ratios of sparkling wine and CO2 bubbles can provide valuable information about the sugar sources. Keywords: Sparkling wine; isotopic composition; C4 sugar; CO2; bubbles
Tropical hydroelectric reservoirs generally constitute an appreciable source of CH4 (methane), a potent greenhouse gas. In this letter, we investigate the statistical characteristics of methane ...ebullition fluxes in hydroelectric reservoirs. To this end, we use CH4 flux measurements obtained in Manso (wet season, 2004) and Corumbá (dry and wet seasons, 2005) reservoirs, located respectively in Mato Grosso and Goiás, Brazil. Methane ebullition fluxes were measured using open dynamic chambers, connected to an infrared photo‐acoustic trace gas analyzer (TGA). Our main result indicates that when properly rescaled, all methane ebullition data collapse into a single statistic well described by a Generalized Pareto distribution, with shape parameter well above zero. The approach presented here, which combines high‐frequency CH4 ebullition data and Extreme Value theory analytical tools, shows that, although bubbling patterns appear to be highly complex and unpredictable, they may still be described by a rather simple (but non trivial) dynamics.
Our objective was to measure the stable carbon isotope composition of leaf tissue and CO2 released by respiration (δr), and to use this information as an estimate of changes in ecosystem isotopic ...discrimination that occur in response to seasonal and interannual changes in environmental conditions, and land‐use change (forest‐pasture conversion). We made measurements in primary forest and pastures in the Amazon Basin of Brazil. At the Santarém forest site, δr values showed a seasonal cycle varying from less than −29‰ to approximately −26‰. The observed seasonal change in δr was correlated with variation in the observed monthly precipitation. In contrast, there was no significant seasonal variation in δr at the Manaus forest site (average δr approximately −28‰), consistent with a narrower range of variation in monthly precipitation than occurred in Santarém. Despite substantial (9‰) vertical variation in leaf δ13C, the average δr values observed for all forest sites were similar to the δ13C values of the most exposed sun foliage of the dominant tree species. This suggested that the major portion of recently respired carbon dioxide in these forests was metabolized carbohydrate fixed by the sun leaves at the top of the forest canopy. There was no significant seasonal variation observed in the δ13C values of leaf organic matter for the forest sites. We sampled in pastures dominated by the C4 grass, Brachiaria spp., which is planted after forest vegetation has been cleared. The carbon isotope ratio of respired CO2 in pastures was enriched in 13C by approximately 10‰ compared to forest ecosystems. A significant temporal change occurred in δr after the Manaus pasture was burned. Burning removed much of the encroaching C3 shrub vegetation and so allowed an increased dominance of the C4 pasture grass, which resulted in higher δr values.
We investigated the forms and composition of dissolved and particulate organic matter in rivers of the$Ji-Paran\acute{a}$Basin, which is situated at the southern limit of the Amazon lowlands and has ...experienced extensive deforestation in the last three decades ($\sim 35 000 km^2$). Our objective was to investigate how extensive land-use changes, from forest to cattle pasture, have affected river biogeochemistry. We measured a series of chemical, biochemical, and isotopic tracers in three size classes of organic matter within five sites along$Ji-Paran\acute{a}$River and eight more sites in six tributaries. The results were compared with C4leaf and pasture soils end members in order to test for a pasture-derived signal in the riverine organic matter. The coarse size fraction was least degraded and derived primarily from fresh leaves in lowland forests. The fine fraction was mostly associated with a mineral soil phase, but its ultimate source appeared to be leaves from forests; this fraction was the most enriched in nitrogen. The ultrafiltered dissolved organic matter (UDOM) appeared to have the same source as the coarse fraction, but it was the most extensively degraded of the three fractions. In contrast to Amazon white-water rivers, rivers of the$Ji-Paran\acute{a}$Basin had lower concentrations of suspended solids with a higher carbon and nitrogen content in the three size fractions. However, principal component analyses showed a correlation between areas covered with pasture and the δ13C values of the three size fractions. The highest δ13C values were observed in the ultrafiltered dissolved organic matter of the Rolim-de-Moura and$Jar\acute{u}$rivers, which have the highest areas covered with pasture. The lower the order of the streams and the higher the pasture area, the greater is the possibility that the$C_{4}-derived$organic matter signal will be detected first in the faster-cycling fraction (UDOM). The large change in land use in the$Ji-Paran\acute{a}$Basin, replacement of primary forests by C4pastures for cattle feeding, that has taken place in the last 30-40 yr, has already changed the characteristics of the composition of the riverine organic matter.
This paper discusses ways to reconcile the United Nations Millennium Development Goals with environmental sustainability at the national and international levels. The authors argue that development ...and better use of sustainability relevant knowledge is key, and that this requires capacity building globally, and especially in the less developed regions of the world. Also essential is stronger integration of high-quality knowledge creation and technology--and policy--development, including, importantly, the creation of centers of excellence in developing regions which effectively use and produce applications-directed high quality research and bring it to bear on decision making and practices related to environmental change and sustainable management of natural resources. The authors argue that Southern centers of excellence are a necessary first step for bottom-up societal transformation towards sustainability, and that such centers must help design innovative ways to assess and place value on ecosystem services.
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