ABSTRACT. The objective of this research was to identify the influence of the evaporative adiabatic cooling system (EACS) on the thermal comfort and productive responses of dairy cattle, through multivariate analysis by principal components (PC), in the summer and winter seasons of the semiarid region of Pernambuco, Brazil. The data came from an experiment that included 16 multiparous lactating cows (7/8 Holstein-Gyr), randomly distributed in 4 sets, with 4 experimental phases and 4 treatments (0, 10, 20, and 30 min.). The multivariate analysis was carried out through PC for the thermal comfort indices, physiological variables, and milk production and composition. The highest milk production in the summer season was obtained for animals exposed to the cooling system for 30 min. In the winter season in the morning period, the use of the EACS for 10 min. was sufficient for improvements in milk production. The times of exposure to EACS caused changes in the composition of milk, for both seasons. Principal component analysis made it possible to verify a positive correlation of evaporative cooling with thermal comfort, physiological responses, and production and composition of milk of lactating cows.

Abstract Intense soil preparation and disturbance in crops, over time, reduces the quantity and quality of soil organic matter. Given this context, this work aimed to determine soil carbon stocks and labile fractions under agroforestry system (AFS) and toposequences in an altitude marsh, Taquaritinga do Norte, Pernambuco, Brazil. The study was carried out at the Yaguara farm, and the areas studied were native forest with 4.57 ha and coffee plantation in shade with native forest with 25.59 ha. Soil samples were collected in four trenches measuring 1.5 x 1.5 x 0.60 m, with a distance of 50 meters. Soils were collected at depths of 0-20, 20-40 and 40-60 cm, followed by chemical, physical and density analyzes to determine soil carbon stocks and labile fractions. The area with shaded coffee showed higher values of soil carbon stocks at depths of 0-20 cm and 20-40 cm. At a depth of 40-60 cm, the AFS top toposequence showed the highest carbon stock with 11.73 Mg ha-1, followed by the area with native vegetation with 10.6 Mg ha-1, slope with 9.23 Mg ha-1 and pediment with 7.00 Mg ha-1. It was found that the top toposequence with shaded coffee exhibited a greater stock of labile carbon at depth 0-20 cm with a value of 1.06 Mg ha-1, followed by the bedding areas (SAF) with 0.88 Mg ha-1, native forest with 0.79 Mg ha-1 and slope with 0.67 g kg-1. However, the area of native vegetation showed the highest value of labile carbon at a depth of 40-60 cm. It was concluded that the area with shaded coffee in the top toposequence showed great capacity to increase total carbon stocks and labile carbon stocks of soil organic matter.

Resumo O intenso preparo e revolvimento do solo em cultivos, com o tempo, reduz a quantidade e a qualidade da matéria orgânica do solo. Diante desse contexto, este trabalho teve como objetivo determinar os estoques de carbono do solo e frações lábeis sob sistema agroflorestal (SAF) e topossequências em brejo de altitude, em Taquaritinga do Norte, Pernambuco, Brasil. O estudo foi desenvolvido na fazenda Yaguara, e as áreas estudadas foram mata nativa com 4,57 ha e plantio de café sombreado com mata nativa com 25,59 ha. As amostras de solos foram coletadas em quatro trincheiras 1,5 x 1,5 x 0,60 m, com distância de 50 metros. Foram coletados solos nas profundidades de 0-20, 20-40 e 40-60 cm, seguido de análises químicas, físicas e densidade para determinação dos estoques de carbono no solo e frações lábeis. A área com café sombreado apresentou maiores valores de estoques de carbono no solo nas profundidades de 0-20 cm e 20-40 cm. Na profundidade de 40-60 cm, a topossequência de topo do SAF apresentou maior estoque de carbono com 11,73 Mg ha-1, seguido da área com vegetação nativa com 10,6 Mg ha-1 , encosta com 9,23 Mg ha-1 e pedimento com 7,00 Mg ha-1. Verificou-se que a topossequência de topo com café sombreado exibiu maior estoque de carbono lábil na profundidade 0-20 cm com o valor de 1,06 Mg ha-1, sucedido das áreas de pedimento (SAF) com 0,88 Mg ha-1, mata nativa com 0,79 Mg ha-1e encosta com 0,67 Mg ha-1. No entanto, a área de vegetação nativa apresentou o maior valor de carbono lábil na profundidade de 40-60 cm. Concluiu-se que a área com café sombreado na topossequência topo mostrou grande capacidade para elevar os estoques de carbono total e estoques de carbono lábil da matéria orgânica do solo.

Anthropic activities are responsible for the increase in environmental contamination, especially in aquatic systems, demanding studies to assess and monitor contamination levels in different water bodies. We have done a chemical characterization of eleven sediments in order to evaluate the level of contamination by domestic sewage from the Capibaribe River, between the cities of Santa Cruz do Capibaribe and Toritama in the state of Pernambuco, Brazil. The classical analyses were performed, as well as the determination of sterol biomarkers using liquid chromatography coupled to tandem mass spectrometry. Sterol ratios corroborated the presence of fecal-derived organic matter, mainly in the sediments collected in regions of higher population occupation. The multivariate statistical analysis clearly showed the regions from the most contaminated to the least contaminated, indicating the severe contamination by domestic sewage in the region. To the best of our knowledge, this is the first study to assess anthropic contamination of the Capibaribe River by using sterol biomarkers and classical analyses in an integrative data interpretation. This can be helpful when making decisions about preventive and corrective actions for human health concerns. systems bodies Pernambuco Brazil performed spectrometry fecalderived fecal derived matter occupation region knowledge interpretation concerns

Abstract An adequate amount of soil organic matter is considered essential for long-term sustainable agriculture, ensuring good productivity. Therefore, the present study quantified carbon and nitrogen stocks and microbiological activity in soil of three different areas: Forest-pasture System, Pasture System and preserved Caatinga - used as a reference of the experiment - located in a semi-arid region, in Watershed of Pajeú River, state of Pernambuco, Brazil. Eight trenches were opened in each system to collect soil samples at depths of 0 - 10, 20 - 30 and 50 - 60 cm, for chemical and microbiological analysis. In general, attributes of soil showed better results of land use in the following order: preserved Caatinga - Forest-pasture System - Pasture System.

ABSTRACT. This study aimed to analyze the principal components of the meteorological variables, physiological and behavioral response of cows subjected to different cooling times and their influence on milk quality, in the dry and rainfall periods, and to establish multiple regression models for milk quality. The data used in the study came from an experiment conducted in the Agreste Region of Pernambuco. The pre-milking cooling time was 10, 20, 30 min. and the control (without cooling). Sixteen multiparous lactating Gir cows were selected. Data were analyzed by principal component analysis and a multiple regression analysis was applied to determine milk quality. There was a strong relationship between somatic cell count (SCC) and activity of the animal in the shade for dry, and lying for rainfall, with increased SCC in cow milk. It was possible to establish two multiple regression models to determine milk quality in dry and rainfall periods. According to the principal component analysis, the cooling time to meet the thermal requirement of the animals was 20 min., regardless of the season and milking shift.