Modelagem espacial da erosão hídrica do solo associada à sazonalidade agroclimática na região sul do Rio Grande do Sul, Brasil / Spatial modeling of soil water erosion associated with agroclimatic seasonality in the southern region of Rio Grande do Sul, Brazil

RESUMO A erosão hídrica constitui um sério problema de degradação do solo, com impacto em diversas áreas. Sua mensuração é de extrema importância e onerosa. Os modelos empíricos de estimativa de perdas de solo, como a Equação Universal de Perda de Solo Revisada (RUSLE), são utilizados para suprir essa demanda. Consideram-se poucos estudos no Brasil que avaliam o efeito da sazonalidade agroclimática nas estimativas de perda de solo por erosão hídrica em bacias hidrográficas. Dessa forma, o objetivo deste estudo foi avaliar a sazonalidade agroclimática na estimativa de perdas de solo por meio da RUSLE e identificar os fatores que controlam a erosão na Bacia Hidrográfica do Arroio Fragata (BHAF). O fator erosividade da chuva (R) e a média anual de precipitação foram calculados por meio de dados de quatro estações pluviométricas.. O fator erodibilidade do solo (K) foi obtido a partir de informações de solo. O fator topográfico (LS) foi gerado com base no modelo digital de elevação (MDE) e o fator cobertura do solo e práticas conservacionistas (CP) por meio de imagens do satélite Landsat8/OLI. A variação sazonal teve efeito na perda de solo, com maiores taxas de erosão no período de verão e primavera. Perdas de solo entre 5 e 50 Mg ha-1ano-1 foram registradas em 24% da BHAF, associadas a períodos de chuvas mais erosivas, maior declividade e baixa cobertura vegetal. Os fatores da RUSLE com maior contribuição na erosão foram R, LS e CP. A abordagem apresentada pode ser útil para quantificar as perdas de solo em bacias hidrográficas.

ABSTRACT Water erosion is a serious soil degradation problem, with impact in several areas. Its measurement is extremely important and costly. Empirical models of soil loss estimation, such as the revised universal soil loss equation (RUSLE), are used to meet this demand. Few studies in Brazil are considered to evaluate the effect on agroclimatic seasonality in the estimates of soil loss due to water erosion in watersheds. Thus, the objective of this study was to evaluate the agroclimatic seasonality in the estimation of soil losses through RUSLE and to identify the factors that control erosion in the watershed of the Fragata stream. Rainfall erosivity (R) was calculated by means of precipitation data for four seasons and annual average. The soil erodibility factor (K) was obtained from soil information. The topographic factor (LS) was generated from the Digital Elevation Model (MDE) and the soil cover factor and conservationist practices (CP) through Landsat8/OLI satellite images. Seasonal variation had an effect on soil loss, with higher erosion rates in the summer and spring months. Soil losses between 5 and 50 Mg ha-1ano-1 were recorded in 24% of the BHAF, associated with periods of more erosive rainfall, higher slope and low vegetation cover. RUSLE factors with the greatest contribution to erosion were R, LS, and CP. The approach presented can be useful in quantifying soil losses in river basins.

Study of socio-demographic and treatment profile and other epidemiological correlates of clients attending revised national tuberculosis control programme clinic in a tertiary hospital of West Bengal, India

Background: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis bacteria spread by droplet infection.According to global TB report 2017, there were approximately 28 lakhs cases of TB in India accounting a quarter of the world TB cases. Today, it is the fastest-expanding and the largest program in the world in terms of patients initiated on treatment and the second largest in terms of population coverage. The objective of this study is to assess the socio-demographic profile of the patients attending revised national TB control programme (RNTCP) clinic, to determine the nature of disease, its co-morbidities, seasonal variability and treatment profile of the patients attending the RNTCP clinic during this study period.Methods: This was a retrospective record-based study conducted in RNTCP clinic of KPC Medical College and Hospital, Kolkata. Details of all the 684 patients who were enrolled under RNTCP from the year 2014 to 2018 were collected from RNTCP records. Data was analyzed using suitable software.Results: 684 cases were registered and treated under directly observed treatment, short-course (DOTS) during the study period with 41% completing treatment. 84.3% were new TB cases. 23.61% were sputum smear positive. Males (67.25%) contributed to more in cases. Maximum patients visited during March to June. 74.87% of the total patients were diagnosed with pulmonary TB. Pleural effusion was the commonest form of extrapulmonary TB (42.75%).Conclusions: The number of TB cases showed a decreasing trend over the years. Males contributed to a greater number of cases with majority being contributed by the age group 21-30 years.

Comparative study of seasonal variability in peak expiratory flow rate amongst school children in rural and urban areas

Background: Peak Expiratory Flow (PEF) is a value test for lung function and can be conveniently measured by using relatively inexpensive and portable Peak Flow Meter, identifying and assessing the degree of airflow limitation of individuals. While PEFR is obviously related to factors like age, weight, height, race, gender, it may also be additionally affected by seasons and climate. The purpose of study being to observe seasonal variation in PEFR amongst school going children and to observe peak expiratory flow rate in school going children in urban and rural areas.Methods: This prospective and comparative study was carried out on total 600 children; with 300 each from rural and urban schools, of age group 10-14 years, both sexes. Peak expiratory flow meter was used for the measurements in the seasons of summer (April to June) and winter (December to February) of the year. The results thus obtained were compiled and analysed.Results: The mean PEFR value (Litres/min) during summers in the rural children was 243.50(S.D.=16.050) while during winters was 253.63(S.D.=16.934), highly significant (p<0.001); mean PEFR summers in the urban children was 241.50(S.D.=20.530)and during winters was 249.93(S.D.=21.685), again highly significant (p<0.001).In both rural and urban groups PEFR values increased with increase in height and weight of the children which was found to be highly significant (p<0.001). Girls representation proportion in rural vs urban schools being 49% vs 45%; whereas boys being 51% vs 55% respectively.Conclusions: Peak expiratory flow rate decreased during summer season of the year in both rural and urban school attending children. In both the groups PEFR values had a direct correlation with height and weight of the children. Rural schools showed more girl student representation than their urban counterparts indicating more awareness for girl child education amongst rural population.

Influencia del sustrato en la composición de la ictiofauna en zonas someras de la laguna costera Barra de Navidad, México

Introducción: Las lagunas costeras son hábitats importantes para los peces costeros y juegan un rol esencial como áreas de crianza para muchas especies. Mientras que los efectos de la salinidad y la temperatura sobre la abundancia de los peces han sido bien documentados, las investigaciones sobre la influencia de las características del sustrato son más escasas. Objetivo: Investigar la correlación de la salinidad, la temperatura y las características del sedimento con las variaciones espaciales y temporales de la composición de la ictiofauna en las zonas someras de la laguna costera Barra de Navidad. Métodos: Se tomaron muestras de la ictiofauna con un chinchorro playero a lo largo de un periodo de dos años en cuatro sitios de la laguna. La salinidad y la temperaturadel agua se midieron simultáneamente con las operaciones de muestreo. Se determinaron el tamaño de partículas del sedimento y su contenido de materia orgánica en cuatro momentos a lo largo del periodo de muestreo.Métodos multivariantes fueronutilizados para el análisis de los datos. Resultados: Un total de 13 487 peces pertenecientes a 69 especies fueron recolectados, pero solo cinco taxones(Eucinostomus currani, Mugil setosus, Anchoa sp., Diapterus brevirostris, Centropomus robalito) conformaron más del 80 % de los individuos. Se encontraron diferencias significativas en la composición de la ictiofauna entre todos los sitios de muestreo y entre las estaciones del año. El análisis de redundancia mostró que los cambios en la ictiofauna estuvieron relacionados principalmente con el porcentaje de lodo y el contenido de materia orgánica del sedimento, como expresión de un gradiente espacial. La influencia de la salinidad y la temperatura fue significativa también, pero estas variables explicaron una proporción menor de la variabilidad observada y estuvieron relacionadas principalmente con los cambios estacionales. Conclusiones: El tamaño de las partículas del sedimento y el contenido de materia orgánica del mismo son los factores abióticos más importantes que influyen en los cambios espaciales de la composición de la ictiofauna. Los cambios estacionales estuvieron correlacionados con cambios en la salinidad y la temperatura, pero podrían estar vinculados también a procesos biológicos como la reproducción y el reclutamiento.

Introduction: Coastal lagoons are important habitats for coastal fishes playing an essential role as nursery areas for many species.While the effects of salinity and temperature on fish abundance spatial and temporal variation have been well documented, research on the influence of substrate characteristics is scarce. Objective: To investigatethe correlation of salinity, temperature and sediment characteristics with spatial and temporal variations of the ichthyofauna composition in Barra de Navidad coastal lagoon´s shallow zones. Methods: Samples of ichthyofauna were taken with a beach purse seine along a period of two years in four sites. Water salinity and temperature were measured simultaneously with fish sampling operations. Sediment particle size and organic matter content were determined four times at each site during the sampling period. Multivariate methods were used for data analyses. Results: A total of13 487 fish pertaining to 69 species were collected, but only five taxa (Eucinostomus currani, Mugil setosus, Anchoa sp., Diapterus brevirostris, Centropomus robalito) made up more than 80 % of the individuals. Significant differences among all sampling sites and between seasons were found for the ichthyofauna composition. Redundancy analysis showed that changes in ichthyofaunal composition were mainly related to the percentage of mud and organic matter in sediments expressing a spatial gradient. The influence of salinity and temperature was also significant, but these variables explained a smaller proportion of the observed variability and were related mainly to seasonal changes. Conclusions: Sediment particle size and organic matter content are the most important abiotic factors influencing spatial changes in shallow water ichthyofaunal composition. Seasonal changes were correlated with changes in salinity and temperature but could also be related to biological processes such as reproduction and recruitment.

The Physiochemical, Biological Quality and Seasonal Variability of River Ganges in Varanasi, Uttar Pradesh, India

Background: The Ganga River is a life-line, a symbol of purity and virtue for countless people of India. Nearly all the sewage, industrial effluent, runoff from chemical fertilizers and pesticides used in agriculture within the basin, and large quantities of solid waste, including thousands of animals carcasses and hundreds of human corpses are dumped in the river everyday which posed a considerable public health threat to the religious bathers and a large number of people living along the river who uses Ganges water for drinking and other household purposes. Objective: To assess the physiochemical and biological quality of river Ganges water and to study the seasonality pattern of pollution of River Ganges. Materials and Methods: Two points namely Samne ghat and Rajghat (entry and exit point of Ganga into the city) were selected as the first and the last sampling stations, beside 8 other intermediate sampling stations to assess the physiochemical and biological quality of River Ganga water. The study was conducted from April 2013 to March 2014 and this period was crudely divided into three seasons viz Winter, Summer and Rainy season for the purpose of studying seasonality pattern of pollution. Results: As the river progress through city of Varanasi, Total dissolved solids (TDS), Chloride, Conductivity, Biochemical Oxygen Demand (BOD), Nitrate, Nitrite and Most Probable Number (MPN) increases, DO decreases progressively and Temperature and pH remain same. Conclusion: As far as quality of water with regard to recreational and industrial purposes are concerned, Ganges water may be considered useful but most of the parameters observed across different seasons indicates that it may not be used as potable water.

Geoquímica de rios de água preta do sudeste do Amazonas: origem, fluxo dos elementos e consumo de CO2 / Geochemistry of black water rivers from the southeastern of the Amazonas State: source, element fluxes and consumption of CO2

This work examined the chemical composition of waters from tributaries of the right bank of the Madeira River which drain silicaterocks of the Brazilian Craton. The study was conducted at the municipalityof Apui, in the southeastern of the Amazonas State, Brazil. There were analyzed pH, conductivity, SiO2 and dissolved ions (Na+, K+, Mg2+ e Ca2+, HCO3-, Cl-, NO3- and SO4(2-)) in the four pluviometric seasons of the Amazon region: rainy, transition to the dry, dry and transition to the rainy. The waters are diluted, have high HCO3-and SiO2 concentration and represent the typical environment of intense leaching that affects the rocks in the Amazon. Although the chemical composition reveals seasonal influences, it was identified variation due to lithological composition. The rate of exportation of cations and the chemical erosion are low in consequence of the tectonic stability of the region and the weathering mantle, which hinders the interaction of water with the bedrock.

Neste trabalho foi examinada a composição química das águas dos afluentes da margem direita do rio Madeira que drenam as rochas do Escudo Brasileiro. O estudo foi realizado no município de Apuí no sudeste do estado do Amazonas, Brasil. Foram analisados pH, condutividade, as concentrações de SiO2 e de íons dissolvidos (Na+, K+, Mg2+, Ca2+, HCO3-, Cl-, NO3- e SO4(2-)) em quatro épocas do ano segundo o índice pluviométrico: chuvosa, transição para a estiagem, estiagem e transição para a chuvosa. As águas são diluídas, mais concentradas em HCO3- e SiO2 e representam o típico ambiente de intensa lixiviação que afeta as rochas na Amazônia. Apesar da química das águas terem influência da sazonalidade, foram identificadas variações em função da litologia. As taxas de exportação de cátions e de erosão química das rochas são baixas e refletem a estabilidade tectônica da região e o manto intempérico que dificulta a interação da água com o substrato rochoso.

Concentración estacional de micronutrientes en hojas de cuatro especies forestales del Parque Chaqueño, Argentina / Seasonal micronutrients concentration in leaves of four forest species from Parque Chaqueño, Argentina

Nutrients cycling is a fundamental component in the functioning of forest ecosystems. Leaves of different forest species observe specific chemical composition, and some seasonal differences in biomass production, may be related to climate fluctuations and/or changes in plant phenology and the variation on nutrient contents. The objective of this study was to analyze the seasonal variability of Fe, Mn, Cu and Zn concentrations in leaves of Gleditsia amorphoides (Ga); Patagonula americana (Pa); Maclura tinctoria (Mt) and Astronium balansae (Ab) from Colonia Benítez Strict Nature Reserve (Chaco, Argentina). The leaves of each forest species were collected monthly, dried at 70ºC and their weight by tree species were recorded. Samples for analytical determinations were prepared by humid oxidation of organic substances from vegetal nets, using oxidant acids such as ternary mixture of HNO3-H2SO4-HClO4. After digestion, total micronutrients leaves concentrations were determined by atomic absortion spectrophotometry. Leaves Fe highest values were detected during fall in Mt (76.1mg/kg), Pa (75.2mg/kg), Ab (59.5mg/kg) and Ga (45.3mg/kg). Highest foliar concentrations of Mn were detected in Pa (54.0mg/kg), Ga (50.0mg/kg), Mt (48.0mg/kg), and Ab with the lower Mn concentration (39.7mg/ kg). No significant differences were found for Cu between the different forest species, standing for Pa (11.3mg/ kg), Ga and Mt (11.0mg/kg) and Ab (10.4mg/kg). With regard to leaves Zn, highest concentrations were found in Mt (347.4mg/kg), Ga (319.9mg/kg), Pa (280.2mg/kg) and Ab (255.7mg/kg). Generally, a marked seasonal variation was observed for Mn and Cu concentrations (except in Ga) and Zn (except in Pa), with no statistical differences for Fe. in the species studied, the concentration of micronutrients analyzed showed a marked and erratic seasonal variation, attributed to the relationship established between the native species, and the strong influence of the environment over a long period of time, especially temperature and rainfall.

El ciclo de nutrientes es uno de los componentes fundamentales en el funcionamiento de los ecosistemas forestales. Las hojas de diferentes especies forestales muestran distinta composición química y diferencias estacionales en la producción de biomasa atribuidas a las fluctuaciones climáticas y/o cambios en la fenología de las plantas y a la variación en el contenido de nutrientes. El objetivo del trabajo fue analizar la variación estacional de las concentraciones de Fe, Mn, Cu y Zn en hojas de: Gleditsia amorphoides (Ga), Patagonula americana (Pa), Maclura tinctoria (Mt) and Astronium balansae (Ab). El sitio de estudio fue localizado en la Reserva Natural Estricta de Colonia Benítez (Chaco, Argentina). Las hojas de cada especie forestal fueron recogidas mensualmente, secadas a 70ºC, se determinó su peso seco y posteriormente se molió. El análisis foliar se realizó por oxidación húmeda empleando una mezcla ternaria HNO -H SO -HclO. Después de la digestión la concentración total de micronutrientes foliares fue determinada por espectrometría de absorción atómica. Las mayores concentraciones de Fe fueron para Mt (76.1mg/kg), Pa (75.2mg/kg), Ab (59.5mg/ kg) y Ga (45.3mg/kg). En Mn las más altas concentraciones se detectaron en Pa (54.0mg/kg), Ga (50.0mg/kg), Mt (48.0mg/kg), y la menor en Ab (39.7mg/kg). No se hallaron diferencias significativas entre las especies forestales para Cu foliar en Pa (11.3mg/kg), Ga y Mt (11.0mg/kg) y Ab (10.4mg/kg). Las mayores concentraciones foliares de Zn fueron en Mt (347.4mg/kg), Ga (319.9mg/kg), Pa (280.2mg/kg) y Ab (255.7mg/kg). En las especies forestales estudiadas, la concentración de los micronutrientes analizados mostraron una errática variación estacional, que puede ser atribuida a las relaciones establecidas entre las especies nativas bajo la fuerte influencia del ambiente, especialmente temperaturas y precipitaciones, durante un largo período de tiempo.

Zooplankton community dynamics in relation to the seasonal cycle and nutrient inputs in an urban tropical estuary in Brazil / Dinâmica da comunidade zooplanctônica em relação a um ciclo sazonal e aportes de nutrientes em um estuário urbano tropical no Brasil

Micro- and mesozooplankton were studied in the Sergipe estuary, northeastern Brazil, in order to assess the temporal variability in abundance and biodiversity under stressed conditions (urban pollution). Zooplankton samples and abiotic data were collected at one station during a full tidal cycle in July 2001 and in February 2002, corresponding to the rainy and dry seasons, respectively. The salinity regime was euhaline-polyhaline. Phosphate and dissolved oxygen were higher in July 2001, and nitrite, nitrate and ammonia in February 2002. Chlorophyll-a concentrations were low as a result of light limitation, with 1.18 ± 0.88 µg.m-3 in February and 1.53 ± 1.48 µg.m-3 in July. Fifty-nine zooplankton taxa were identified. Microzooplankton were abundant, mainly the tintinnid Favella ehrenbergii, and ranged from 18,649 ind.m-3 in July to 678,009 ind.m-3 in February. Mesozooplankton ranged from 1,537 ind.m-3 in July to 37,062 ind.m-3 in February and were dominated by barnacle nauplii in July and by copepods in February. The cluster analysis by taxa revealed the existence of three distinct groups: resilient species, characteristic of estuarine areas and occurring during all the year; species mainly more abundant in July (indicators of a healthier environmental condition); and species more abundant in February (tolerant to poor water quality).

O micro-e o mesozooplâncton foram estudados no estuário do rio Sergipe, Nordeste do Brasil para conhecer a variação temporal em abundância e biodiversidade sob condições de estresse. Amostras do zooplâncton e dados abióticos foram coletados em uma estação durante um ciclo completo de marés em julho de 2001 e em fevereiro de 2002, correspondendo aos períodos chuvoso e seco, respectivamente. O regime de salinidade variou de euhalino a polihalino. O fosfato e o oxigênio dissolvidos foram mais elevados em julho 2001, e o nitrito, o nitrato e a amônia, em fevereiro 2002. As concentrações de clorofila-a foram baixas devido à limitação da luz, com valores médios de 1,18 ± 0,88 µg.m-3 em fevereiro e 1,53 ± 1,48 µg.m-3 em julho. Foram identificados 59 taxa zooplanctônicos. O microzooplâncton foi abundante, principalmente o tintinídeo Favella ehrenbergii, que variou de 18.649 ind.m-3 em julho a 678.009 ind.m-3 em fevereiro. O mesozooplâncton variou de 1.537 ind.m-3 em julho a 37.062 ind.m-3 em fevereiro e foi dominado por náuplios de Cirripedia em julho e por Copepoda em fevereiro. A análise de agrupamento por taxa revelou a existência de três grupos: espécies resilientes, características de áreas estuarinas de ocorrência contínua; espécies que dominaram em julho (indicadores de uma melhor condição ambiental); e espécies mais abundantes em fevereiro (tolerantes à baixa qualidade da água).

Variabilidade sazonal no ducto epididimário de codorna doméstica: observações morfológicas / Seasonal variability in epididymal duct of the domestic quail: morphologic features

O ducto epididimário (DE) de codorna doméstica mostrou, ao longo do ano, variabilidade pequena, porém muito expressiva no outono, o qual corresponde à fase quiescente do ciclo testicular anual. A morfologia do DE na primavera foi, em termos, similar à verificada no verão e inverno. Nestas fases notaram-se aumento significante do calibre tubular do DE; estocagem intraluminal de espermatozóides e ocorrência de mitocôndrias, lamelas do RE, vesículas variáveis quanto à forma, dimensões e conteúdos e presença de alguns lisossomos localizados, principalmente, no citoplasma apical das células principais (P), no epitélio epididimário. Estas características ultra-estruturais das células P parecem ser indicativas da ocorrência de processos ativos de endocitose e de secreção micromerócrina. A quiescência outonal foi caracterizada pelo aspecto anfractuoso do DE; ausência de espermatozóides e pouco material intraluminal, observados à microscopia de luz. Características ultra-estruturais degenerativas foram verificadas ao nível do citoplasma supranuclear das células P epididimárias no outono.

Small but expressive variability was noted on the epididymidis duct (ED) of domestic quail along the year, with more evidence in autumn of the quiescent phase of the annual testis cycle in this species. Spring features of ED had a general similar pattern in summer and winter. They were characterized by enlargement of epididymis tubule, storage of spermatozoa into the luminal compartment and presence of mitochondria, ER lamellae, several variable vesicles, and lysosomes localized mainly on the apical cytoplasm of principal cells (P) of the epididymal epithelium. These P cells features indicated a process of endocytosis and perhaps protein secretion. Autumn quiescence was marked by a convolute pattern of the epididymis tubule, lacking of spermatozoa and small amount of exfoliate heterogeneous material inside the luminal compartment at light microscopy. Ultrastructural degenerative features mainly apical cytoplasmic debris were seen in the supranuclear cytoplasm of lining P cells.

Variabilidade sazonal de constituintes químicos (triterpenos, flavonóides e polifenóis) das folhas de Maytenus aquifolium Mart. (Celastraceae) / Seasonal variability of chemical compounds (triterpenes, flavonoids and polyphenols) from Maytenus aquifolium Mart (Celastraceae) leaves

Estudou-se a variabilidade química sazonal em Maytenus aquifolium Mart. (Celastraceae), conhecida como "espinheira santa", em exemplares cultivados em Ribeirão Preto, SP, através da análise das substâncias presentes nas folhas, ao longo das quatro estações em dois anos. O teor de fenóis totais variou de 21,96 a 45,92 mg / g (expresso em mg ácido tânico / g folhas secas), de 55,88 a 93,20 mg triterpenos totais / g folhas secas, e de 1,349 a 3,859 mg flavonóides / g folhas secas. A amostra Primavera 92 apresentou o maior teor de flavonóides e fenóis totais, e a amostra Inverno 94 apresentou o maior teor de triterpenos.

The chemical seasonal variability of Maytenus aquifolium Mart. (Celastraceae), a Brazilian medicinal plant known as "espinheira santa", was investigated on specimens cultivated at Ribeirão Preto SP, Brazil, at the four seasons of two years. The content of total phenolics, flavonoids and triterpenes varied from 21.96 to 45.92 mg total phenolics (expressed as tanic acid) / g dried leaves, 55.88 - 93.20 mg total triterpenes / g dried leaves, and 1.349 - 3.859 mg flavonoid / g dried leaves. Sample Spring 92 had the higher content of flavonoids and total phenolics, while sample Winter 94 had the highest content of triterpenes.