Desempenho de métodos de estimativa da evapotranspiração de referência nas localidades de Frederico Westphalen e Palmeira das Missões, RS

A estimativa da evapotranspiração de referência (ETo), usada no balanço hídrico, possibilita quantificar o armazenamento de água no solo, auxiliando no manejo da irrigação. O objetivo do trabalho foi comparar métodos mais simples de estimativa da evapotranspiração de referência com o método Penman-Monteith (FAO), nas escalas diária e de 5, 10, 15 e 30 dias, e mensal, para os municípios de Frederico Westphalen e Palmeira das Missões, no RS. Os métodos avaliados tenderam a melhorar a eficiência com o aumento da escala temporal de estudo, mantendo o mesmo desempenho para ambas as localidades. Os maiores e menores valores de ETo ocorreram nos meses de dezembro e junho, respectivamente. A maioria dos métodos subestimou os valores de ETo. Em qualquer escala temporal, os métodos de Makking e da Radiação FAO24 podem substituir o modelo de Penman-Monteith.

Perfomance of methods for estimating reference evapotranspiration in the municipalities of Frederico Westphalen and Palmeira das Missoes, State of Rio Grande do Sul, Brazil

The estimation of reference evapotranspiration (ETo), used in water balance, allows to determine soil water content, assisting on irrigation management. The present study aimed to compare simple ETo estimating methods with the Penman-Monteith (FAO), in the folowing time scales: daily, 5, 10, 15 and 30 days and monthly in the counties of Frederico Westphalen and Palmeira das Missoes, in the Rio Grande do Sul state, Brazil. The methods tested had their efficiency improved by increasing the time scale of analysis, keeping the same performance for both locations. The highest and lowest ETo values occurred in December and June, respectively. Most methods underestimated ETo. For any of the time scales Makking and Radiaton FAO24 methods can replace the Penman-Monteith for estimating ETo.

Geographical distribution of American cutaneous leishmaniasis and its phlebotomine vectors (Diptera: Psychodidae) in the state of São Paulo, Brazil

Abstract Background American cutaneous leishmaniasis (ACL) is a re-emerging disease in the state of São Paulo, Brazil. It is important to understand both the vector and disease distribution to help design control strategies. As an initial step in applying geographic information systems (GIS) and remote sensing (RS) tools to map disease-risk, the objectives of the present work were to: (i) produce a single database of species distributions of the sand fly vectors in the state of São Paulo, (ii) create combined distributional maps of both the incidence of ACL and its sand fly vectors, and (iii) thereby provide individual municipalities with a source of reference material for work carried out in their area. Results A database containing 910 individual records of sand fly occurrence in the state of São Paulo, from 37 different sources, was compiled. These records date from between 1943 to 2009, and describe the presence of at least one of the six incriminated or suspected sand fly vector species in 183/645 (28.4%) municipalities. For the remaining 462 (71.6%) municipalities, we were unable to locate records of any of the six incriminated or suspected sand fly vector species (Nyssomyia intermedia, N. neivai, N. whitmani, Pintomyia fischeri, P. pessoai and Migonemyia migonei). The distribution of each of the six incriminated or suspected vector species of ACL in the state of São Paulo were individually mapped and overlaid on the incidence of ACL for the period 1993 to 1995 and 1998 to 2007. Overall, the maps reveal that the six sand fly vector species analyzed have unique and heterogeneous, although often overlapping, distributions. Several sand fly species - Nyssomyia intermedia and N. neivai - are highly localized, while the other sand fly species - N. whitmani, M. migonei, P. fischeri and P. pessoai - are much more broadly distributed. ACL has been reported in 160/183 (87.4%) of the municipalities with records for at least one of the six incriminated or suspected sand fly vector species, while there are no records of any of these sand fly species in 318/478 (66.5%) municipalities with ACL. Conclusions The maps produced in this work provide basic data on the distribution of the six incriminated or suspected sand fly vectors of ACL in the state of São Paulo, and highlight the complex and geographically heterogeneous pattern of ACL transmission in the region. Further studies are required to clarify the role of each of the six suspected sand fly vector species in different regions of the state of São Paulo, especially in the majority of municipalities where ACL is present but sand fly vectors have not yet been identified.

A resource management scenario for traditional and scientific management of pink shrimp (Farfantepenaeus paulensis) in the Patos Lagoon estuary (RS), Brazil

Abstract Background This article aims to discuss the incorporation of traditional time in the construction of a management scenario for pink shrimp in the Patos Lagoon estuary (RS), Brazil. To meet this objective, two procedures have been adopted; one at a conceptual level and another at a methodological level. At the conceptual level, the concept of traditional time as a form of traditional ecological knowledge (TEK) was adopted. Method At the methodological level, we conduct a wide literature review of the scientific knowledge (SK) that guides recommendations for pink shrimp management by restricting the fishing season in the Patos Lagoon estuary; in addition, we review the ethno-scientific literature which describes traditional calendars as a management base for artisanal fishers in the Patos Lagoon estuary. Results Results demonstrate that TEK and SK describe similar estuarine biological processes, but are incommensurable at a resource management level. On the other hand, the construction of a “management scenario” for pink shrimp is possible through the development of “criteria for hierarchies of validity” which arise from a productive dialog between SK and TEK. Conclusions The commensurable and the incommensurable levels reveal different basis of time-space perceptions between traditional ecological knowledge and scientific knowledge. Despite incommensurability at the management level, it is possible to establish guidelines for the construction of “management scenarios” and to support a co-management process.

Dinâmica Sedimentar da Lagoa Itapeva, RS - Brasil.

Os fatores hidrodinâmicos que controlam a sedimentação na Lagoa Itapeva foram avaliados através do mapa de distribuição granulométrica gerado a partir do diagrama de Pejrup e da análise da ação hidrodinâmica induzida pelas ondas no corpo lacustre. Além disso, através do método geocronológico do 210Pb estimou-se a taxa de sedimentação no interior lacustre. Os padrões texturais em amostras sedimentares de fundo indicam a presença de significativa energia hidrodinâmica atuante no processo de sedimentação, com predomínio da fração arenosa nas margens submersas e granodecrescência para tamanhos de silte grosso a fino em direção ao centro. A ação hidrodinâmica induzida pelas ondas é fator condicionante na distribuição dos sedimentos, pois os ventos mais frequentes com média de intensidade de 16 m.s-1, atuando em uma pista de até 31 km, geram ondas com altura significativa de 0,60 m, período de 3,3 s e velocidade orbital de 0,34 m.s-1 junto ao fundo. Como este valor excede o limite para movimentação de sedimentos tamanho areia, essa classe granulométrica predomina juntamente com o silte apresentando baixa concentração no tamanho argila. A taxa de sedimentação foi estimada através da obtenção de três testemunhos de sondagem sendo aplicado o método geocronológico 210Pb a qual indicou taxas de sedimentação na ordem de 2,9 mm.a-1, 2,4 mm.a-1 e 3,2 mm.a-1 no sentido norte sul. A contribuição da drenagem do rio Três Forquilhas foi o principal condicionante na diferença entre estes setores aumentando a taxa de sedimentação perto da desembocadura. A análise granulométrica ao longo dos testemunhos indica a existência de significativa energia hidrodinâmica no processo de sedimentação na área central do corpo lacustre. A fração silte é a classe dominante, com variação de diâmetro entre médio a grosso em todas as amostras, sendo mais comum a ocorrência da fração areia em relação à argila, que apresentou baixa concentração, não ultrapassando 9%.