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1.
Sci Total Environ ; 926: 172127, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38569965

RESUMO

River avulsions drive important changes in the Pantanal wetlands, owing to their role in the hydro-sedimentology of the region. Although relevant to numerous ecosystem services, few studies have analyzed the influence of river avulsions on soil fertility in the Pantanal. Here, we use the largest ongoing avulsion in the Taquari River (Caronal region) to evaluate the effects on soil fertility, considering two factors: avulsion stage (1) and aquatic-terrestrial succession (2). Since both factors are influenced by macrophyte abundance, an incident map was created through tasseled cap indices from Sentinel 2 images to guide sampling efforts in flooded soils. The mapped area was split into two zones of alluvial processes, the first from the apex of the Caronal lobe corresponding to the Taquari River megafan (TRM), and the second as the distal Paraguay River floodplain (PRF). Soil macro- and micronutrient levels were evaluated from 42 surface samples (0-0.2 m) distributed across the two alluvial process zones. The macrophyte map's overall accuracy (OA) was analyzed by a confusion matrix using the Sentinel 2 imagery. Finally, we used Random Forest regressions to determine the influence of response variables on soil attributes, including tassel indices, distance from the Caronal crevasse, macrophyte density, and an existing soil fertility map. The macrophyte map obtained an OA of 93 %. Some parameters such as pH (r = -0.62; R2 = 0.57), effective cation exchange capacity (r = -0.49; R2 = 0.79), Mn (r = -0.71; R2 = 0.6), Zn (r = -0.69; R2 = 0.54), and base saturation (r = -0.7; R2 = 0.93) were influenced by the distance or level of maturation of the avulsion stage in the TRM. Our scattering of soil collections was insufficient to test the terrestrialization hypothesis (2). The study results show that river channel avulsions influence the accumulation of mineral and organic nutrients in tropical floodplain soils, which has implications for fertility and biodiversity.

2.
J Environ Manage ; 323: 116219, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36108507

RESUMO

Soil health is at the core of the sustainability agenda. As in many agroecosystems in the tropics, soil erosion is a major issue in poorly managed pasturelands. A noteworthy case is located in the Upper Taquari River Basin (UTRB), as part of the Upper Paraguay Basin on the plateau with drainage waters for the Taquari megafan in the Brazilian Pantanal. Here we combine slope (S-factor), erodibility (E-factor), rainfall-rainy day ratio (R-factor), and vegetation and soil indices (C-factor) to locate erosion risk and prioritize eco-engineering interventions via palisades and small dams in UTRB. The method consisted of assessing distinct weights between Universal Soil Loss Equation (USLE) factors in a GIS platform, providing 35 combinations of classes as low, moderate, high, and very high erosive risk. The validation of the method was based on the ravine and plain ground truths obtained from high-resolution raster data. The best weight of USLE factors aids to locate critical erosive sites and vegetation patterns. Then, erosion risk and interventions were analyzed according to land use and rural property sizes in the government's Rural Environmental Registry (CAR) database. Overall, the natural factors of slope and erodibility in a proportion of 25% and 75% in GIS algebra provided the best mapping accuracy result. About 65% of the UTRB has high or very high erosion risks, and 70% of the available area can be acknowledged as degraded pasturelands. A total of 4744 erosion interventions were recorded, with an accuracy of 65.28% and 61.15% for check dams and palisades interventions, respectively. The number of necessary interventions in areas of native vegetation was almost 50% higher than in pasturelands. Even though micro landowners occupy most of the watershed, large properties have about ten times as many areas at high risk of erosion. The mutual cooperation between properties, independently of size, is supported by governmental public policies like incentives for ecosystem services restoration of critical gullies, with CAR compliance and fiscalization.


Assuntos
Ecossistema , Solo , Brasil , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Rios , Solo/química
3.
Viruses ; 14(2)2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35215784

RESUMO

Almost two decades after the isolation of the first amoebal giant viruses, indubitably the discovery of these entities has deeply affected the current scientific knowledge on the virosphere. Much has been uncovered since then: viruses can now acknowledge complex genomes and huge particle sizes, integrating remarkable evolutionary relationships that date as early as the emergence of life on the planet. This year, a decade has passed since the first studies on giant viruses in the Brazilian territory, and since then biomes of rare beauty and biodiversity (Amazon, Atlantic forest, Pantanal wetlands, Cerrado savannas) have been explored in the search for giant viruses. From those unique biomes, novel viral entities were found, revealing never before seen genomes and virion structures. To celebrate this, here we bring together the context, inspirations, and the major contributions of independent Brazilian research groups to summarize the accumulated knowledge about the diversity and the exceptionality of some of the giant viruses found in Brazil.


Assuntos
Amoeba/virologia , Vírus Gigantes/genética , Vírus Gigantes/isolamento & purificação , Virologia/história , Biodiversidade , Brasil , Ecossistema , Genoma Viral , Vírus Gigantes/classificação , Vírus Gigantes/ultraestrutura , História do Século XXI , Filogenia
4.
Sci Total Environ ; 761: 143276, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33162127

RESUMO

Brazil is an important player in the global agribusiness markets, in which grain and beef make up the majority of exports. Barriers to access more valuable sustainable markets emerge from the lack of adequate compliance in supply chains. Here is depicted a mobile application based on cloud/edge computing for the livestock supply chain to circumvent that limitation. The application, called BovChain, is a peer-to-peer (P2P) network connecting landowners and slaughterhouses. The objective of the application is twofold. Firstly, it maximizes sustainable business by reducing transaction costs and by strengthening ties between state-authorized stakeholders. Secondly, it creates metadata useful for digital certification by exploiting CMOS and GPS sensor technologies embedded in low-cost smartphones. Successful declarative transactions in the digital space are recorded as metadata, and the corresponding big data might be valuable for the certification of livestock origin and traceability for sustainability compliance in 'glocal' beef markets.

5.
Sci Total Environ ; 723: 138067, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32224399

RESUMO

The Pantanal is an important active sedimentary basin in central South America where highly diverse flora and fauna are sustained by seasonal floods. Intense land use in the catchment areas enhanced sediment load and destabilized avulsive river systems in the plains. A well-known avulsion in the Taquari River during the 1980-90s, called "Zé da Costa", has shifted the river mouth and drastically changed the nearby landscapes, making them difficult to map because of the hard access and the large variations in spectral and spatial attributes of raster data like Landsat images. Therefore, we developed a useful method to map and explore landscape changes in "Zé da Costa" avulsion that combines geotagged field pictures, randomly selected high-resolution orbital truths, normalized difference vegetation index, digital elevation models, linear spectral mixture models and Landsat historical imagery in pixel-based and object-oriented supervised classifications. We found that bands in green, red, and near-infrared spectra provide better mapping results with object-oriented algorithms for deriving and studying temporal dry/wet ratio dynamics. The temporal analyses of the dry/wet ratio showed that avulsions in the Taquari River have the potential to change permanently the "Zé da Costa" area into a dry landscape, making it susceptible for land use (deforestation and fire), except areas seasonally inundated by the floods of the Paraguay River. Overall, our method might be also useful for long-term studies of land use and climate change in avulsive rivers in wetlands around the world.

7.
Sci Total Environ ; 655: 463-472, 2019 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-30472648

RESUMO

Bovine livestock is a major anthropogenic greenhouse gas source via enteric methane. Brazilian bovine livestock is also responsible for emissions from land-use changes. In contrast, enteric emissions from extensive cattle systems in wetlands might have been overestimated. We provide scientific evidences that the human footprint of bovine products delivered by the Pantanal can be much lower. To assess this, a historical cloud-free imagery of the Landsat-5, spanning 26 years, were processed for mapping spatiotemporal landscapes in a Pantanal farm under cattle intensification studies. Eight landscape categories were identified according to spatiotemporal dynamics of interannual floods. The spatiotemporal map allowed in the field the adoption of stratified random samplings of chamber gas fluxes. The combination of stratified sampled landscapes with Monte Carlo simulations of measured methane emissions in wet and dry soils permitted to integrate landscapes emissions at annual basis with biased uncertainties. Assuming enteric emissions obtained for the Pantanal region, our results suggest that the landscapes methane emissions are 10- to 23-fold superior than the enteric emissions of traditional bovine systems. While enteric emissions seem negligible with respect to net farmland emissions, cattle livestock provide important environmental services like carbon recycling through non-competing herbivory. Moreover, cattle might be making use of a biomass that would undergo decomposition during the flooding phase. Our analysis thus indicate that enteric emissions from traditional bovine systems in flooding farmlands could be considered neutral. By contrast, intensification to improve the stocking rate should be accounted as net anthropogenic emissions. A case study of intensification allowed an increase of 48% in the stocking rate, which is associated with net anthropogenic emissions from 534 bovine animals or about 27 to 63 Mg of enteric CH4 per year. In short, the competition between traditional and distinct levels of cattle intensification will result from a trade-off between public policies and strategic market niches (organic, sustainable) for the optimal landscape management of the Pantanal.


Assuntos
Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/tendências , Gases de Efeito Estufa/análise , Metano/análise , Áreas Alagadas , Animais , Brasil , Bovinos , Conservação dos Recursos Naturais , Sistemas de Informação Geográfica , Análise Multivariada , Análise de Componente Principal
8.
Sci Total Environ ; 619-620: 1116-1125, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29734590

RESUMO

The Pantanal is a large wetland mainly located in Brazil, whose natural resources are important for local, regional and global economies. Many human activities in the region rely on Pantanal's ecosystem services including cattle breeding for beef production, professional and touristic fishing, and contemplative tourism. The conservation of natural resources and ecosystems services provided by the Pantanal wetland must consider strategies for water security. We explored precipitation data from 1926 to 2016 provided by a regional network of rain gauge stations managed by the Brazilian Government. A timeseries obtained by dividing the monthly accumulated-rainfall by the number of rainy days indicated a positive trend of the mean rate of rainy days (mm/day) for the studied period in all seasons. We assessed the linkage of Pantanal's rainfall patterns with large-scale climate data in South America provided by NOAA/ESRL from 1949 to 2016. Analysis of spatiotemporal correlation maps indicated that, in agreement with previous studies, the Amazon biome plays a significant role in controlling summer rainfall in the Pantanal. Based on these spatiotemporal maps, a multi-linear regression model was built to predict the mean rate of summer rainy days in Pantanal by 2100, relative to the 1961-1990 mean reference. We found that the deforestation of the Amazon rainforest has profound implications for water security and the conservation of Pantanal's ecosystem services.


Assuntos
Conservação dos Recursos Naturais/métodos , Floresta Úmida , Abastecimento de Água/estatística & dados numéricos , Áreas Alagadas , Brasil
9.
Nat Commun ; 9(1): 749, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487281

RESUMO

Here we report the discovery of two Tupanvirus strains, the longest tailed Mimiviridae members isolated in amoebae. Their genomes are 1.44-1.51 Mb linear double-strand DNA coding for 1276-1425 predicted proteins. Tupanviruses share the same ancestors with mimivirus lineages and these giant viruses present the largest translational apparatus within the known virosphere, with up to 70 tRNA, 20 aaRS, 11 factors for all translation steps, and factors related to tRNA/mRNA maturation and ribosome protein modification. Moreover, two sequences with significant similarity to intronic regions of 18 S rRNA genes are encoded by the tupanviruses and highly expressed. In this translation-associated gene set, only the ribosome is lacking. At high multiplicity of infections, tupanvirus is also cytotoxic and causes a severe shutdown of ribosomal RNA and a progressive degradation of the nucleus in host and non-host cells. The analysis of tupanviruses constitutes a new step toward understanding the evolution of giant viruses.


Assuntos
Mimiviridae/genética , Amoeba/virologia , Brasil , Evolução Molecular , Genoma Viral , Especificidade de Hospedeiro/genética , Interações Hospedeiro-Patógeno/genética , Lagos/microbiologia , Microscopia Eletrônica , Mimiviridae/metabolismo , Mimiviridae/ultraestrutura , Oceanos e Mares , Filogenia , Biossíntese de Proteínas , Proteoma/genética , RNA Ribossômico 16S/genética , RNA Viral/genética , Proteínas Virais/genética , Microbiologia da Água
10.
Virol J ; 15(1): 22, 2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29368617

RESUMO

BACKGROUND: Since the discovery of giant viruses infecting amoebae in 2003, many dogmas of virology have been revised and the search for these viruses has been intensified. Over the last few years, several new groups of these viruses have been discovered in various types of samples and environments.In this work, we describe the isolation of 68 giant viruses of amoeba obtained from environmental samples from Brazil and Antarctica. METHODS: Isolated viruses were identified by hemacolor staining, PCR assays and electron microscopy (scanning and/or transmission). RESULTS: A total of 64 viruses belonging to the Mimiviridae family were isolated (26 from lineage A, 13 from lineage B, 2 from lineage C and 23 from unidentified lineages) from different types of samples, including marine water from Antarctica, thus being the first mimiviruses isolated in this extreme environment to date. Furthermore, a marseillevirus was isolated from sewage samples along with two pandoraviruses and a cedratvirus (the third to be isolated in the world so far). CONCLUSIONS: Considering the different type of samples, we found a higher number of viral groups in sewage samples. Our results reinforce the importance of prospective studies in different environmental samples, therefore improving our comprehension about the circulation anddiversity of these viruses in nature.


Assuntos
Microbiologia Ambiental , Vírus Gigantes/genética , Vírus Gigantes/isolamento & purificação , Amoeba , Animais , Regiões Antárticas , Brasil , DNA Viral , Genoma Viral , Geografia , Vírus Gigantes/classificação , Vírus Gigantes/ultraestrutura , Humanos , Filogenia , Análise de Sequência de DNA
11.
Sci Total Environ ; 532: 281-91, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26081730

RESUMO

Fast pyrolysis of naturally produced water hyacinth was assessed through Emergy accounting approach. Two analyses were carried out to evaluate the influence of additional services and externalities on Emergy indicators for a pyrolysis plant unit able to process 1000 kg of dry biomass per hour. The initial approach was a traditional Emergy assessment in which financial fluxes and externalities were not considered. The second approach included taxes and fees of the Brazilian government, interests related to financing operations and assumes a reserve financial fund of 5% of the total investment as externalities cost. For the first evaluation, the renewability of 86% indicates that local and renewable resources mainly support the process and the Emergy Yield Ratio of 3.2 shows that the system has a potential contribution to the regional economy due to the local resources use. The inclusion of financial fluxes and externalities in the second evaluation reduces both renewability and Emergy Yield Ratio, whereas it increases the Emergy Investment Ratio which means a higher dependence on external resources. The second analysis allows portraying significant forces of the industrial and financial systems and the evaluation of the externalities' impact on the general system Emergy behavior. A comparison of the renewability of water hyacinth fast pyrolysis with other biofuels like soybean biodiesel and sugarcane ethanol indicates that the former is less dependent on fossil fuel resources, machinery and fertilizers. To complement the sustainability assessment provided by the Emergy method, a regular financial analysis for the second defined system was done. It shows that the system is financially attractive even with the accounting of additional costs. The results obtained in this study could be used as the maximum and minimum thresholds to subsidize regulatory policies for new economic activities in tropical wetlands involving natural resources exploitation and bio-industrial systems.

13.
Sci Total Environ ; 463-464: 1060-6, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23891998

RESUMO

Human activities in the highlands alter the usual ecohydrological dynamics of the Pantanal wetland in the lowlands. These alterations can be noted by historical observation and identification of key processes that change the normal ecohydrology in the highlands and lowlands. Depending on land-use scenarios in the near future, the ongoing changes in the highlands may have positive or deleterious effects on the Pantanal's carrying capacity and resilience for providing ecosystem services such as nutrient retention and recycling, water purification, fish stocks, among others. This article seeks to summarize recent information to clarify, guide and provide support for the pursuit of realistic scenarios and induce scientific research and government policies that reconcile sustainable development in the highlands and lowlands, in line with the conservation of the Pantanal wetland.

14.
Chemosphere ; 92(6): 714-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23582405

RESUMO

This work provides data on the production of biochar from the pyrolysis of the solid phase of swine effluents following anaerobic biodigestion. The study involved the low vacuum thermochemical conversion by environmental scanning electron microscope (ESEM) in a thermoregulated hot-stage tungsten SEM. The feedstock was characterized by FTIR, ESEM and energy dispersive X-ray analysis (EDS). The charred feedstock at peak temperatures of 300°C, 400°C, 500°C, 600°C, 700°C, and 1000°C were assessed by SEM and EDS. For each pyrolysis experiment, the exhaust gases were monitored by photoacoustic spectroscopy. SEM/EDS indicated that for increasing peak temperature in low vacuum pyrolysis, the mass losses are greater and the proportion of mineral particles such as P, Ca and Mg in the biochar. Photoacoustic spectroscopy showed that low vacuum pyrolysis is responsible for emissions of toxic gases NH3 and SO2 and radiative trace gases, especially N2O above 600°C.


Assuntos
Carvão Vegetal/química , Esterco/análise , Eliminação de Resíduos , Suínos , Anaerobiose , Animais , Temperatura Alta , Eliminação de Resíduos/métodos , Suínos/metabolismo , Vácuo
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