Livestock’s critical role in net-zero food systems

Presentation on the critical role of livestock in the global agenda for food systems to achieve net zero emissions presented by Lina Wollenberg and Ciniro Costa at COP27, Nov 2022, Sharm el-Sheikh, Egypt

Yield and nutritive value of oat forage cultivated in Selvíria, MS, Brazil

O presente ensaio visou testar a viabilidade de produção e a produtividade da forrageira de inverno "aveia-preta" (Avena strigosa Schreb.), cultivada em um Latossolo Vermelho-Amarelo do Município de Selvíria, MS, sob irrigação. A aveia foi semeada em 05.05.1980 e cortada quando as plantas atingiram 35 cm, 45 cm ou 55 cm de altura. As rebrotas foram cortadas uma vez atingidas as mesmas alturas. Avaliaram-se as produções de matéria seca (MS) por hectare, proteína bruta (PB) por hectare e percentagem de proteína (PB%) na matéria seca. O tratamento que forneceu melhores resultados foi aquele em que as plantas foram cortadas aos 45 cm de altura. Nessas condições, foram produzidas 1,59 t/ha de proteína e 5,38 t/ha de MS com uma média de 29,60% de PB, em três cortes, realizados aos 50, 79 e 103 dias após a semeadura.As an aid to solve the low forage availability problem during the dry winter season, an irrigated trial with forage oat (Avena strigose Schreb.) was carried out, on a Red-Yellow Latosol of Selvíria, MS, Brazil. That is a "cerrado" area and the major objective was to assess the best forage productivity and its nutritive value. Oat was sown on May 5, 1980, and harvested when plants were at 35 cm, 45 cm or 55 cm in height. The successive regrowths were ever cut at the same height. Dry matter (DM), crude protein (CP) yields and crude protein content (CP%) indicated that harvesting plants at 45 cm height was the best management treatment. This treatment supplyed 5,38 t/ha of DM, containing 29,6% CP in DM, resulting in 1,59 t/ha of CP when plants were harvested at 50, 79 and 103 days after sowing.

Executive leadership in semi-presidential systems

Relative to presidentialism and parliamentarism, the study of semi-presidentialism is still in its infancy. The term was coined in 1970 and, apart from the pioneering work of Maurice Duverger, systematic study began only in the 1990s. Previously, the definition of semi-presidentialism was the subject of much debate. Now, most scholars agree that semi-presidentialism is where there is both a directly elected fixed-term president and a prime minister and cabinet that are collectively responsible to the legislature. The key contribution of recent scholarship is that semi-presidentialism is not a unimodal category. Instead, there is a tremendous variety of executive politics in countries with a semi-presidential constitution. This work has identified the effects of such variation on topics such as democratic performance and both government formation and termination. Given so many countries now have semi-presidential constitutions, the study of this topic is likely to remain salient. In the future, there should be more comparative studies of semi-presidential countries and more systematic comparisons of semi-presidentialism with presidentialism and parliamentarism

Greenhouse gas emission caused by different land-uses in brazilian Savannah

A conversão de áreas nativas com o corte e queima de vegetação seguida do cultivo do solo resultam em mudanças na dinâmica da matéria orgânica do solo, com alterações nas emissões dos gases causadores de efeito estufa (GEE: CO2, CH4 e N2O) da biosfera para a atmosfera, que causam a elevação da temperatura média e, consequentemente, as mudanças climáticas globais. O objetivo deste estudo foi verificar as relações entre os fluxos de CO2, CH4 e N2O com a umidade, biomassa microbiana e as formas inorgânicas de N no solo com diferentes usos das terras no bioma Cerrado (Rio Verde, Goiás). O clima da região é do tipo Aw (Köppen-Geiger), e o solo foi classificado como Latossolo Vermelho distrófico caulinítico textura argilosa com vegetação original de Cerradão. O delineamento experimental foi inteiramente casualizado (DIC), com quatro tratamentos (áreas): vegetação nativa - Cerradão (CE); pastagem (PA) de braquiária, semeadura convencional (SC) de soja; e semeadura direta (SD) de milho sucedido por milheto. As emissões anuais de CO2 e N2O não mostraram diferenças significativas entre os tratamentos; isso ocorreu devido à elevada variação nos fluxos dos gases em decorrência da sazonalidade no clima, com as menores emissões observadas durante o inverno, devido à ausência da umidade do solo. A média na emissão de CO2 foi de 108,9 ± 85,6 mg m-2 h-1 , e para o N2O, de 13,5 ± 7,6 µg m-2 h-1. Os fluxos de CH4 apresentaram diferenças significativas somente para a pastagem, com emissão de 32 µg m-2 h-1 , enquanto nas demais áreas foram observados influxos entre 46 e 15 µg m-2 h-1 . Com os resultados das correlações, pode-se verificar que a umidade foi a variável do solo que apresentou maior correlação com o fluxo dos três gases de efeito estufa. O teor de N-NO3- e as emissões de CO2 mostraram correlações para todas as áreas. Quando consideradas as correlações para todos os tratamentos conjuntamente, verificou-se que os fluxos dos três gases apresentaram correlações significativas com os teores de C e N-microbiano. Contudo, a relação Cmicro:Nmicro não mostrou correlação significativa com o fluxo dos gases de efeito estufa. A pastagem foi a única situação em que os fluxos de CO2 e N2O apresentaram correlação com as quantidades de N-inorgânico. Os resultados sugerem que os fluxos dos GEE são dependentes do regime pluvial no bioma Cerrado, principalmente nas áreas cultivadas que recebem altas doses de fertilizantes para o aumento da produtividade.The conversion of native forests by cutting and burning into farming areas leads to alterations in the dynamics of soil organic matter, with changes in emissions of greenhouse gases (GHGs: CO2, CH4 and N2O) from the biosphere to the atmosphere. These cause an average temperature rise and, consequently, global climate change. The aim of this study was to examine relationships between the fluxes of CO2, CH4 and N2O with moisture, microbial biomass and inorganic N forms in soil with different land uses in the Cerrado biome (Rio Verde county, State of Goias - Brazil). The climate (Köppen-Geiger) was classified as Aw and the soil as Latossolo Vermelho distrófico caulinítico / a clayey kaolinitic Oxisol under original Cerrado (Brazilian savanna) vegetation. The experiment was arranged in a completely randomized design (CRD) with four treatments (areas): Native vegetation - Cerrado (CE); brachiaria pasture (PA); soybean in conventional tillage (SC) and no-tillage (NT) corn followed by millet. No significant differences in annual CO2 and N2O emissions were observed between treatments. This can be explained by the variability of gas fluxes due to climate seasonality, with lower emissions in the winter due to low soil moisture. Mean emissions of CO2 were 108.9 ± 85.6 mg m-2 h-1 , and of N2O 13.5 ± 7.6 mg m-2 h-1 . For CH4 significant differences in the fluxes were only observed in pasture (32 mg m-2 h-1 ), while in the other areas inflows between 46 and 15 mg m-2 h-1 were observed. The GHG fluxes showed close correlation with soil moisture. The N-NO3- emissions were significantly correlated with CO2-emissions in all areas. Considering all treatments together, the three GHG fluxes were correlated with the microbial C and N contents. However, the Cmicro: Nmicro ratio was not significantly correlated with the GHG flux. Only for pasture the CO2 and N2O fluxes were correlated with the content of soil inorganic-N. Results suggested that the GHG fluxes in the Cerrado are related to rainfall, mainly in farming areas treated with high fertilizer doses to increase productivity.Fundação AgrisusFAPESPFonds Français pour l'Environnement MondialAFD - Agence Française de DéveloppementMinistério das Relações EstrangeirasCAPES-COFECU

Global Warming Potential* (GWP*): Understanding the implications for mitigating methane emissions in agriculture

KEY MESSAGES: - GWP* (global warming potential) complements conventional climate metrics such as GWP100 because GWP* better describes the actual warming caused by methane (CH4) emissions. For example, using GWP100, a constant annual rate of CH4 emissions may be misinterpreted as having a 3-4 times higher impact on warming than observed. The use of GWP* can correct this misestimation. - GWP* was used here to evaluate the impact of agricultural CH4 emissions scenarios from 2020- 2040, finding that: - A sustained ~0.35% annual decline is sufficient to stop further increases in global temperatures due to agricultural CH4 emissions. This is analogous to the impact of net-zero CO2 emissions. - A ~5% annual decline could neutralize the additional warming caused by agricultural CH4 since the 1980s. - Faster reductions of CH4 emissions have an analogous impact to removing CO2 from the atmosphere. - However, a 1.5% annual increase in CH4 emissions would lead to climate impacts about 40% greater than indicated by GWP100. - The application of GWP* to CH4 emissions accounting suggests that avoiding further warming due to CH4 emissions in agriculture is more attainable than previously understood. CH4 reductions can have a rapid and highly substantial impact, which underscores the importance of making significant cuts in CH4 emissions immediately

Estimating the Potential for Conservation and Farming in the Amazon and Cerrado under Four Policy Scenarios

Since 2013, clearing rates have rapidly increased in the Amazon and Cerrado biomes. This acceleration has raised questions about the efficacy of current regional public and private conservation policies that seek to promote agricultural production while conserving remnants of natural vegetation. In this study, we assessed conservation and agricultural outcomes of four potential policy scenarios that represent perfect adherence to private sector, zero-deforestation commitments (i.e., the Amazon soy moratorium—ASM and the Amazon cattle agreements—CA) and to varying levels of implementation of the Brazilian Forest Code (FC). Under a zero-clearing scenario, we find that the extent of croplands as of 2017 within the two biomes (31 MHa) could double without further clearing if agriculture were to expand on all previously cleared land that is suitable for crops. Moreover, at least 47 MHa of land that is already cleared but unsuitable for crops would remain available for pasture. Under scenarios in which only legal clearing under the FC could occur, 51 MHa of additional natural vegetation could be cleared. This includes as many as 1 MHa of nonforest vegetation that could be cleared in the Amazon biome without triggering the ASM and CA monitoring systems. Two-thirds of the total vegetation vulnerable to legal clearing is located within the Cerrado biome, and 19 MHa of this land is suitable for cropland expansion. Legal clearing of all of these areas could reduce biodiversity persistence by 4% within the two biomes, when compared with the zero-clearing scenario, and release up to 9 PgCO2e, with the majority (75%) coming from the Cerrado biome. However, when we considered the potential outcomes of full implementation of the FC, we found that 22% (11 MHa) of the 51 MHa of vegetation subject to legal clearing could be protected through the environmental quotas market, while an additional 1 MHa should be replanted across the two biomes, predominantly in the Amazon biome (73% of the area subject to replanting). Together, quotas and replanting could prevent the release of 2 PgCO2e that would otherwise be emitted if all legal clearing occurred. Based on our results, we conclude that ongoing legal clearing could create additional space for cropland and cattle production beyond the substantial existing stocks of cleared areas but would significantly impair local carbon and biodiversity stocks.</jats:p

Total soil carbon and chemical attributes under different land uses in the Brazilian savanna

A região do Cerrado representa uma das maiores áreas cultivada do mundo. Os diferentes usos do solo empregados nesta região podem modificar efetivamente as quantidades de matéria orgânica e alterar a ciclagem dos nutrientes no solo. O objetivo deste estudo foi avaliar o efeito de diferentes sistemas de manejo nas relações entre o carbono total e os atributos químicos de um Latossolo Vermelho distrófico no Cerrado na região de Rio Verde, Estado de Goiás. As áreas estudadas foram cerradão, pastagem de baixa produtividade, plantio convencional de soja e plantio direto de soja com milho em sucessão. Os valores mais baixos no pH, cátions trocáveis, P-disponível e enxofre foram observados no Cerradão, contudo foram encontrados os maiores teores de C-total, que apresentaram correlação elevada com os teores de H+AL e a CTC potencial. Nas demais áreas, foram encontradas concentrações mais elevadas de cátions trocáveis, P-disponível e enxofre. Nas áreas onde não ocorreu o revolvimento do solo e a aplicação do corretivo e dos fertilizantes foi superficial, a estratificação dos teores de C-total promoveu a retenção dos elementos mais próximos à superfície, o que proporcionou correlações significativas com os atributos químicos do solo.The Brazilian savanna region (Cerrado) is one of the largest cultivated areas of the world. The different land uses in the region can effectively change the quantities of soil organic matter and the cycling of nutrients. The objective of this study was to evaluate the effect of different land use management systems on the relationship between soil organic carbon and the soil chemical attributes of a Red Latosol (Oxisol) under Cerrado in Rio Verde (Goiás state). The treatments studied were native vegetation (cerradão), low-productivity pasture, conventional tillage with soybean, and no-tillage with soybean and maize. The smallest values for pH, available P, K, Ca and Mg were observed for the Cerradão treatment, even if the relatively high C levels increased the potential soil cation exchange capacity. The pasture, conventional tillage and no-tillage treatments showed higher K, Ca, Mg, available P, and S concentrations in the soil. In the areas where soil tillage did not take place and lime and fertilizers were applied superficially, the stratification of the soil organic carbon provides the retention of the elements near to the surface, with significance correlations with the soil chemicals attributes.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação AgrisusFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)French Ministry of Foreign AffairsThe Global Environmental Facilit

Botanical composition of cattle diet on rangelands in the Pantanal wetland, Brazil

O estudo foi conduzido com o objetivo de identificar a composição botânica da dieta de bovinos criados extensivamente no Pantanal através da técnica microhistológica fecal, numa área característica da sub-região da Nhecolândia, Pantanal, no período de outubro/97 a setembro/99, e verificar a variação existente em função do mês, época, ano e estado fisiológico das vacas. Foram confeccionadas 726 lâminas, sendo cada lâmina uma unidade observacional. Com base na distribuição dos valores máximos de ocorrência da composição botânica de cada espécie/lâmina e nos quantis, as espécies foram classificadas em quatro grupos principais: 1- principal (máx >20%); 2- médio superior (12,3% 20.0%); 2- medium superior (12.3% <max<=20.0%); 3- medium (6.7<max<=12.3%); 4-occasional (max<+6.7%). These groups represented 11%, 14%, 25% and 50% of the identified species, respectively. A split-plot in distinct time was adjusted envolving each effect (month, season) and its interactions with physiological condition and hydrological year. For all studied groups there were no significant effects of physiological condition of cows and no interaction of physiological condition with period and year on the mean composition of the diet. There were significant effects of season and year for all groups, however, the interaction season x year was significant only for the occasional group