Identificação e caracterização físico-química de latossolos de textura arenosa e média da região oeste da Bahia.

A região do oeste baiano tem tido uma rápida expansão agrícola. No entanto existem ainda poucas informações sobre as características pedoambientais da região. O objetivo deste trabalho foi o caracterizar e interpretar os atributos morfológicos, físicos e químicos de perfis de Latossolos da região oeste da Bahia. Foram identificados e descritos três perfis: LATOSSOLO VERMELHO-AMARELO Distrófico, textura franco-argiloarenosa; LATOSSOLO AMARELO Distrófico psamítico, textura areia franca/franco-arenosa; LATOSSOLO VERMELHO Distrófico, textura franco-arenosa. As características morfológicas, físicas e químicas dos solos estudados foram determinadas e são apresentadas. Foram analisadas as frações de areia e a constituição mineralógica da fração argila. Foi verificado o predomínio de areia média e areia fina em todas as profundidades dos perfis estudados e a predominância de caulinita na fração argila. Os resultados obtidos indicaram que a capacidade dos solos avaliados em suprir água e nutrientes para as plantas é limitada, em função das características físicas e químicas. Foi observada a presença de uma camada de solo adensada próxima à superfície do solo

Carbon balance of land use, land-use change and forestry (LULUCF) in the Brazilian Chaco.

ABSTRACT. In Brazil, the Steppe Savanna and associated vegetation types, typical of the Chaco, are in the Pantanal biome. Land use in this region has caused the suppression of natural vegetation and the emission of greenhouse gases. The knowledge of the phytophysiognomies of the Chaco and its importance for the mitigation and adaptation to climate change can contribute to conservation and protection policies in this region, including specific public policies to support the sustainable use of biodiversity and carbon stock (C). In this work, we present an estimate of the balance between CO2 emissions and removals associated with land use and land cover changes for the Brazilian Chaco, considering the annual average of C loss or gain in living biomass and dead organic matter in three different periods: 1990 to 2000, 2000 to 2010 and 2010 to 2019. The methodology followed the one recommended by the Fourth National Communication of Brazil to the United Nations Framework Convention on Climate Change, with adaptations. The results show that the natural vegetation of the Brazilian Chaco has been replaced by pasture throughout the studied period (1990-2019). The Savanna Formations had the greatest reduction in area in this period. The balance points to a net emission of 0.12, 0.05, and 0.03 MgCO2 ha-1 year-1, respectively, in 1990-2000, 2000-2010, and 2010-2019. CO2 removals predominate especially in the Kadiweu Indigenous Land, and emissions prevail in the Chaco South region

Corrigendum: proteomic analysis and functional validation of a Brassica oleracea Endochitinase involved in resistance to Xanthomonas campestris.

Na publicação: Maria Fatima Grossi-de-Sá, Angela Mehta

Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at sNN\sqrt{s_{NN}} = 5.02 TeV

Two-particle angular correlations between unidentified charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum range 0.7 $< p_{\rm{T}, assoc} < p_{\rm{T}, trig} <$ 5.0 GeV/$c$ is examined, to include correlations induced by jets originating from low momen\-tum-transfer scatterings (minijets). The correlations expressed as associated yield per trigger particle are obtained in the pseudorapidity range $|\eta|<0.9$. The near-side long-range pseudorapidity correlations observed in high-multiplicity p-Pb collisions are subtracted from both near-side short-range and away-side correlations in order to remove the non-jet-like components. The yields in the jet-like peaks are found to be invariant with event multiplicity with the exception of events with low multiplicity. This invariance is consistent with the particles being produced via the incoherent fragmentation of multiple parton--parton scatterings, while the yield related to the previously observed ridge structures is not jet-related. The number of uncorrelated sources of particle production is found to increase linearly with multiplicity, suggesting no saturation of the number of multi-parton interactions even in the highest multiplicity p-Pb collisions. Further, the number scales in the intermediate multiplicity region with the number of binary nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/161

Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider

Measurements of multi-particle azimuthal correlations (cumulants) for charged particles in p-Pb and Pb-Pb collisions are presented. They help address the question of whether there is evidence for global, flow-like, azimuthal correlations in the p-Pb system. Comparisons are made to measurements from the larger Pb-Pb system, where such evidence is established. In particular, the second harmonic two-particle cumulants are found to decrease with multiplicity, characteristic of a dominance of few-particle correlations in p-Pb collisions. However, when a $|\Delta \eta|$ gap is placed to suppress such correlations, the two-particle cumulants begin to rise at high-multiplicity, indicating the presence of global azimuthal correlations. The Pb-Pb values are higher than the p-Pb values at similar multiplicities. In both systems, the second harmonic four-particle cumulants exhibit a transition from positive to negative values when the multiplicity increases. The negative values allow for a measurement of $v_{2}\{4\}$ to be made, which is found to be higher in Pb-Pb collisions at similar multiplicities. The second harmonic six-particle cumulants are also found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find $v_{2}\{4\} \simeq v_{2}\{6\}\neq 0$ which is indicative of a Bessel-Gaussian function for the $v_{2}$ distribution. For very high-multiplicity Pb-Pb collisions, we observe that the four- and six-particle cumulants become consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and Pb-Pb are measured. These are found to be similar for overlapping multiplicities, when a $|\Delta\eta| > 1.4$ gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87

Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies $E>E_{th}=5.5\times 10^{19}$ eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at $E>E_{th}$ are heavy nuclei with charge $Z$, the proton component of the sources should lead to excesses in the same regions at energies $E/Z$. We here report the lack of anisotropies in these directions at energies above $E_{th}/Z$ (for illustrative values of $Z=6,\ 13,\ 26$). If the anisotropies above $E_{th}$ are due to nuclei with charge $Z$, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies