Disruption of endogenous tidal rhythms of larval release linked to food supply and heat stress in an intertidal barnacle

The timing of larval release may greatly affect the survivorship and distribution of pelagic stages and reveal important aspects of life history tactics in marine invertebrates. Endogenous rhythms of breeding individuals and populations are valuable indicators of selected strategies because they are free of the neutral effect of stochastic environmental variation. The high-shore intertidal barnacle Chthamalus bisinuatus exhibits endogenous tidal and tidal amplitude rhythms in a way that larval release would more likely occur during fortnightly neap periods at high tide. Such timing would minimize larval loss due to stranding and promote larval retention close to shore. This fully explains temporal patterns in populations facing the open sea and inhabiting eutrophic areas. However, rhythmic activity breaks down to an irregular pattern in a population within the São Sebastião Channel subjected to large variation of food supply around a mesotrophic average. Peaks of chl a concentration precede release events by 6 d, suggesting resource limitation for egg production within the channel. Also, extreme daily temperatures imposing mortality risk correlate to release rate just 1 d ahead, suggesting a terminal reproductive strategy. Oceanographic conditions apparently dictate whether barnacles follow a rhythmic trend of larval release supported by endogenous timing or, alternatively, respond to the stochastic variation of key environmental factors, resulting in an erratic temporal pattern.

An investigation about Brazilian mango and grape exports

Purpose - The objective of this paper is to characterise the transactions between European buyers and Brazilian mango and grape producers. Design/methodology/approach - The method selected for this paper was multiple case studies. The Brazilian mango and grape supply chains' export activities to Europe were investigated. The field research was undertaken in Brazil, Germany, The Netherlands and the UK. In total, 41 face-to-face interviews were carried out. Findings - The supermarkets' literature tends to generalise the strategies of retailers focusing on differentiation and preferred suppliers. However, in empirical research conducted in the UK, Germany and The Netherlands it is possible to conclude that the procurement strategies of supermarkets can vary sharply. The results reveal the presence of different agents who demand different quality standards. The level of intensity depends on consumer behaviour, the features of product commercialised and the characteristics of the production segment in each country. Research limitations/implications - First, in relation to the empirical method there is a limitation because the case study does not allow statistical generalisation. Consequently, it will be interesting to undertake quantitative research in order to quantify the variables presented and their impact on the structure of value chains. Second, the research focuses only on two stages of the supply chain, producers and buyers. Practical implications - The differences between UK and German supermarkets challenge the supermarket literature, which tends to generalise the strategies of retailers focusing on differentiation and preferred suppliers. Originality/value - The study shows that the issue of influence and activities of retail agents along the value chain can be analysed taking several variables into consideration: the products commercialised; the distribution segment; and the consumer market. This result opens the way for analysing different structures of the value chain and the impact of these differences on the entry of producers for developing countries into the global market.

Collection of Pollen Grains by Centris (Hemisiella) tarsata Smith (Apidae: Centridini): Is C. tarsata an Oligolectic or Polylectic Species?

Lia Goncalves, Claudia Ines da Silva, and Maria Luisa Tunes Buschini (2012) Collection of pollen grains by Centris (Hemisiella) tarsata Smith (Apidae: Centridini): Is C. tarsata an oligolectic or polylectic species? Zoological Studies 51(2): 195-203. Among pollinator species, bees play a prominent role in maintaining biodiversity because they are responsible, on average, for 80% of angiosperm pollination in tropical regions. The species richness of the bee genus Centris is high in South America. In Brazil, these bees occur in many types of ecosystems. Centris tarsata is an endemic species occurring only in Brazil. No previous studies considered interactions between plants and this bee species in southern Brazil, where it is the most abundant trap-nesting bee. Accordingly, the goals of this study were to investigate plants used by this species for its larval food supply and determine if this bee is polylectic or oligolectic in this region. This work was conducted in the Parque Municipal das Araucarias, Guarapuava (PR), southern Brazil, from Mar. 2002 to Dec. 2003. Samples of pollen were collected from nests of these bees and from flowering plants in grassland and swamp areas where the nests were built. All of the samples were treated with acetolysis to obtain permanent slides. The family Solanaceae was visited most often (71%). Solanum americanum Mill. (28.6%) and Sol. variabile Mart. (42.4%) were the primary pollen sources for C. tarsata in the study area. We found that although C. tarsata visited 20 species of plants, it preferred Solanum species with poricidal anthers and pollen grains with high protein levels. This selective behavior by females of C. tarsata indicates that these bees are oligolectic in their larval provisioning in this region of southern Brazil. http://zoolstud.sinica.edu.tw/Journals/51.2/195.pdf

Entre o declínio e a reinvenção: atualidade das funções do sistema público atacadista de alimentos no Brasil

Este artigo apresenta evidências das mudanças que estão se processando no aparato atacadista público de alimentos no Brasil abordando a evolução, as características atuais e as funções da estrutura atacadista do sistema brasileiro de abastecimento. O texto aborda algumas considerações sobre o contexto histórico vivido no momento de criação do Sistema Nacional de Abastecimento (Sinac) nos anos 70 e a emergência de novos modelos para os mercados atacadistas a partir dos anos 80. É realizada uma análise com base na observação dos dados coletados junto a 29 centrais de abastecimento públicas brasileiras em 2009 com informações sobre origem e destino dos hortigranjeiros comercializados nesses entrepostos a partir de uma amostra significativa. Os padrões sistêmicos podem ser observados através de dois aspectos: o desempenho da atividade econômica dos principais entrepostos atacadistas brasileiros e as funções remanescentes de reunião e distribuição da produção local e regional. Pretendemos demonstrar que o grupo de centrais públicas de abastecimento é bastante heterogêneo e que, de maneira geral, a dinâmica do seu crescimento é estabelecida de fora para dentro , sendo que muitos destes equipamentos não mais exercem papéis centrais como executores de políticas públicas voltadas para o abastecimento.

The role of empirical research in the study of complex forms of governance in agroindustrial systems

The growing complexity of supply chains poses new challenges for Agricultural Research Centers and statistical agencies. The aim of this perspective paper is to discuss the role of empirical research in understanding the complex forms of governance in agribusiness. The authors argue that there are three fundamental levels of analysis: (i) the basic structure of the market, (ii) the formal contractual arrangements that govern relations within the agroindustrial system and (iii) the transactional dimensions governed by non-contractual means. The case of the agrochemical industry in Brazil illustrates how traditional analyses that only address market structure are insufficient to fully explain the agricultural sector and its supply chain. The article concludes by suggesting some indicators which could be collected by statistical agencies to improve understanding of the complex relationships among agribusiness segments. In doing so, the paper seeks to minimize costs and to enable a better formulation of public and private policies.

Sustentabilidade e cadeia de suprimentos: uma perspectiva comparada de publicações nacionais e internacionais

O objetivo do artigo é apresentar um quadro de referência de conceitos da Gestão da Sustentabilidade na Cadeia de Suprimentos (GSCS) para auxiliar pesquisas futuras na tentativa de integração intra e interorganizacional fundamentada em aspectos da sustentabilidade. Trata-se de um artigo teórico, cujo procedimento metodológico adotado foi o desk research em periódicos da área de gestão e operações, realizado em duas etapas. Na primeira, buscou-se visualizar os estudos da temática em seis importantes periódicos internacionais da área, totalizando 53 artigos entre 1954 e 2009. Esta etapa gerou uma evolução da temática, contribuindo para apontar tendências. Na segunda, foram revisados seis periódicos nacionais da área de administração. Selecionaram-se 11 artigos, publicados entre 1961 e 2009, resultando em um panorama da temática no contexto acadêmico brasileiro. O conceito de GSCS apareceu apenas em 2007, o que mostra a atualidade do tema, embora este seja a junção de temáticas anteriormente estudadas.

Food-Retail Development and the Myth of Everyday Low Prices: The Case of Brazil

This article analyses the changes in Brazilian food retailing by investigating the co-existence of, and the pricing variation across, large supermarket chains and small independent supermarkets. It uses cointegration tests to show that, despite the widespread belief that small supermarkets are inefficient and charge higher prices, they in fact charge lower prices. Accordingly, in contrast to the prevailing literature on food-retail development, competition in food retail is complex and cannot be described as a simple Darwinian process of market concentration. The article explores the survival of small retail and its consequences for the current discussion on modern food retail in developing countries.