Riqueza vegetal en patios familiares del trópico mexicano: hallazgos desde la teoría de polos de desarrollo / Species richness in residential yards of the Mexican tropics: findings from development pole theory

Resumen La riqueza de especies existentes en el patio familiar es el resultado de la coincidencia de procesos sociales, económicos, culturales y ambientales, que suceden más allá de sus límites físicos. Una teoría aún vigente para comprender estos factores externos es la teoría de polos de desarrollo. El objetivo de la presente investigación fue conocer la riqueza de especies vegetales comestibles versus ornamentales en patios familiares de 13 comunidades de Paso de Ovejas, Veracruz y la influencia que tiene en ello el polo de desarrollo más cercano (cabecera municipal). Se aplicó una encuesta consistente en 443 cuestionarios, a través de un muestreo no probabilístico de tipo accidental. En el análisis de los datos se usó estadística descriptiva e inferencial (componentes principales) y los índices de familiaridad (IF), valor de uso (IVU) y consenso del informante (ICF). Los resultados obtenidos sugieren que la riqueza de especies ornamentales versus comestibles está relacionada con la lejanía o cercanía al polo de desarrollo. La influencia de este polo afecta la dinámica socioeconómica familiar, cuyos miembros, si bien evidencian un alto grado de familiaridad con las especies existentes en sus patios familiares, también expresan la generación de condiciones de posibilidad para que parte de ellas (especies comestibles) puedan ser progresivamente abandonadas en su uso y manejo, como sucede en una comunidad de la ruta 3. Se concluye que, en la determinación de la riqueza de especies del patio familiar interviene el polo de desarrollo, como un factor exógeno, el cual trastoca la dinámica familiar en las comunidades que lo circundan. Dicha información se considera relevante para los tomadores de decisiones en el diseño de estrategias de fortalecimiento de este agroecosistema tradicional.

Abstract The richness of plant species in residential yards is the result of the coincidence of social, economic, cultural and environmental processes that occur beyond their physical boundaries. A still relevant theory to understand these external factors is the Theory of Poles of Development. The objective of this research was to know the richness of edible versus ornamental plant species in residential yards of 13 communities in Paso de Ovejas, Veracruz, and the influence that the development pole (municipal head) has on it. 443 questionnaires were administered through a non-probabilistic accidental type sampling procedure. Data analysis involved descriptive and inferential statistics (main components), and the application of indexes of Familiarity (IF), Use Value (IVU) and Informant Consensus (ICF). The results obtained suggest that the richness of ornamental versus edible species is influenced by the distance or proximity to the development pole. The influence of this development pole will affect family socioeconomic dynamics, whose members show a high degree of familiarity with the species existing in their family yards, but also express that the generation of conditions of possibility in such a way that part of edible species can be progressively abandoned in their use and management, as happens in a community on route 3. It is concluded that the determination of the species richness of residential yards is influenced by the development pole as an exogenous factor, which disrupts family dynamics in the surrounding communities. Such information is considered relevant for decision makers in the design of strategies to strengthen this traditional agroecosystem.

Diversity of sarcosaprophagous Diptera (Calliphoridae, Sarcophagidae) in organic and conventional mango plantations in the Brazilian semi-arid region

ABSTRACT Increase on intensive monocultures is an important threat to Caatinga biodiversity decrease. The use of chemical insecticides directly affects insect natural enemies of crops, but also non-target species. We aimed to test whether the diversity of sarcosaprophagous flies would be affected by agricultural management (conventional and organic). Adult dipterans were collected monthly, from July 2015 to January 2016, using a grid composed of 12 suspended traps distant 20 m from each other, baited with 150 g of sardine or bovine spleen, in each type of management. We first calculated α-diversity by Hill numbers, then evaluated the difference of diversity metrics by ANOVA. We also graphically visualise the species composition distribution by NMDS. We recorded a total of 4,651 specimens of 15 Calliphoridae and Sarcophagidae species. Chrysomya spp. were the dominant species (93.7% of all blowflies). Sarcophagidae species were sampled in low abundance, but with exclusive presence of some species in each treatment (e.g. B laesoxipha stallengi and Ravinia belforti in organic management). Although there was no difference on sarcosaprophagous fly diversity between treatments, we demonstrate empirically that mango plantations in the Caatinga harbour diverse and abundant assemblages of sarcosaprophagous dipterans, whose richness of species is comparable to other ecosystems such as rainforests and urban areas. Our results expand the known geographical range for forensically relevant species by providing a checklist of sarcosaprophagous dipterans that can thrive in agroecosystems in the Caatinga and, potentially, colonize cadavers disposed in that type of environment.

Can agroecological management increase functional diversity of birds in rice fields?

Introduction: Recognition of the variety of ecosystem services that biodiversity performs in agroecosystems is one of the basic principles of agroecology. Because indices of functional diversity may be directly related with ecosystem services, an assessment of functional diversity can be useful for evaluating ecosystem services provided under agroecological management. Objective: We compared functional diversity of birds found in rice fields under conventional and agroecological management in the rice zone of Santa Fe Province, Argentina. Our objective was to determine whether agroecological management of rice is associated with a higher functional diversity and a different functional composition of birds than conventional management. Methods: We surveyed birds eight times, roughly every 15 days between November 2017 and March 2018, from beginning of sowing to before harvest, in both types of rice fields. Birds were sampled by a combined technique of line transects and point counts at four sites in each type of management. We calculated indices of functional diversity and composition based on morphologic and trophic attributes of birds detected in each type of field. Results: Functional richness, divergence and dispersion were higher under agroecological management. Only differences in functional richness between managements reflected differences in species richness. Community-level weighted means of trait values by sample varied between management types. An insectivorous diet, pursuit as a foraging method, and air and shrubs as foraging substrates were traits best represented under agroecological management. Conclusions: Our results suggest that agroecological management of rice crops is related with a higher functional diversity of birds than conventional practices, suggesting that agroecological management may enhance the provision of ecosystem services by birds in rice agroecosystems.

Introducción: El reconocimiento de la variedad de servicios ecosistémicos de la biodiversidad en los agroecosistemas es uno de los principios básicos de la agroecología. Debido a que los índices de diversidad funcional pueden estar directamente relacionados con los servicios ecosistémicos, la evaluación de la diversidad funcional representa una estrategia adecuada para evaluar estos servicios en agroecosistemas bajo manejo agroecológico. Objetivo: Se comparó la diversidad funcional de aves entre arroceras bajo manejo convencional y agroecológico en la zona arrocera de la provincia de Santa Fe, Argentina. El objetivo fue determinar si el manejo agroecológico del arroz se asocia con una mayor diversidad funcional y con una diferente composición funcional de aves en relación con el manejo convencional. Métodos: Se muestrearon las aves mediante 8 conteos repetidos aproximadamente cada 15 días entre noviembre 2017 y marzo 2018, desde el comienzo de la siembra hasta antes de la cosecha, en ambos tipos de arroceras. Los muestreos fueron realizados mediante una técnica mixta combinando transectas de línea y puntos de conteo en cuatro sitios por tipo de manejo. Se calcularon índices de diversidad y composición funcional con base en atributos morfológicos y tróficos de las aves registradas. Resultados: La riqueza, la divergencia y la dispersión funcional fueron más altos bajo manejo agroecológico. Solamente en el caso de la riqueza funcional las diferencias reflejaron únicamente la variación de la riqueza de especies. La media ponderada a nivel de ensamble de los valores de los rasgos por muestra varió entre los tipos de manejo, estando la dieta insectívora, la persecución como método de forrajeo, y el aire y los arbustos como sustrato de forrajeo mejor representados bajo manejo agroecológico. Conclusión: Los resultados sugirieron que el manejo agroecológico del arroz se relaciona con una mayor diversidad funcional de aves que las prácticas de manejo convencional, sugiriendo que el manejo agroecológico puede mejorar la provisión de servicios ecosistémicos por aves en cultivos de arroz.

Estimación de la sustentabilidad de fincas productoras de arveja en el municipio de Ipiales, Nariño-Colombia / Estimation of the sustainability of farm producers of vegetables in the municipality of Ipiales, Nariño-Colombia

RESUMEN Los agroecosistemas muestran una gran heterogeneidad en cuanto a las prácticas y características, debido a que dependen de las lógicas de la agricultura familiar, convirtiéndose en un recurso potencialmente valioso, cuando se estudia el uso y el soporte del medio productivo. Es por ello, que esta investigación evaluó el sistema de arveja (Pisum sativum L.) en el municipio de Ipiales, a través de una metodología multidimensional, usando 26 indicadores, agrupados en cuatro dimensiones de sustentabilidad agroecológica. La estimación, se realizó sobre 30 fincas, que representaron tres tipos de campesinos, previamente descritos, como C1, C2 y C3; los resultados permitieron identificar los Puntos Críticos de Sustentabilidad (PCS) y el Índice General de Sustentabilidad (IGS) del sistema, estableciendo que las diferentes situaciones sociales, ambientales, económicas y técnico-productivas determinan la existencia de PCS específicos. El IGS tuvo una calificación de 2,65, para C1; 2,90, para C2 y 2,62, para C3, evidenciando medidas de monitoreo y de manejo, que se deberían discutir en la región, para disminuir las externalidades generadas por el modelo productivo.

ABSTRACT Agroecosystems present great heterogeneity in terms of practices and characteristics, since they depend on the logic of family farming, which makes them a potentially valuable resource when studying the use and support of the productive environment. For this reason, this research evaluated the pea system (Pisum sativum L.) in the municipality of Ipiales, through a multidimensional methodology that uses 26 indicators grouped into four dimensions of agroecological sustainability. The estimation was made on 30 farms that represented three types of farmers previously described as C1, C2 and C3; the results allowed identifying the Critical Points of Sustainability (CPS) and the General Index of Sustainability (GIS) of the system. It was established that the different social, environmental, economic and technical-productive situations determine the existence of specific CPS, the GIS had a rating of 2.65 for C1, 2.90 for C2 and 2.62 for C3, this evidenced monitoring and management measures that should be discussed in the region to reduce the externalities generated by the production model.

A Micro Level Investigation of Costs & Returns of Different Agro-ecosystems in Kashmir Region of Jammu and Kashmir: India

The basic objectives of the study were to enquire in to the involvement of various types of costs, the returns per rupee invested and the benefit thereof in different agro-ecosystems in the state of Jammu and Kashmir in general and valley of Kashmir in particular, especially the sampled districts. This study was based upon primary and secondary data. A multi-stage random sampling was utilised for collection of date from 432 respondents of four different agro-ecological zones. For major crops, the cost of cultivation were estimated by concept utilised by Commission on Agricultural Costs and Prices (CACP), Government of India. The results revealed that fruit crop agro-ecosystem is highly remunerative than field crop and crop agro-ecosystems, though the fruit crop involve huge of investment in terms of different costs. The livestock based agro-ecosystem is also dominant in some parts of the Kashmir region with declining trend. The results revealed that the gross returns of paddy and apple, livestock and cash crop were Rs. 23250, Rs. 321000, Rs. 108920 and 106915 respectively. This study had its applicability in the daily routine life of any household dwelling in the sampled agro-ecosystems. The study could be of utmost importance in selecting the crop in which the region/agro-ecosystem had specialisation or absolute advantage.

Diversity of parasitoid wasps in conventional and organic guarana (Paullinia cupana var. sorbilis) cultivation areas in the Brazilian Amazon

We surveyed parasitoid wasps (Hymenoptera) in two guarana plantations in the central Brazilian Amazon (one conventionally, and one organically managed), as well as in adjacent forest and edge areas between crop and forest. We evaluated differences between management systems in parasitoid diversity and abundance, and assessed the importance of the surrounding matrix as a source of parasitoid wasps for guarana cultivation. Parasitoid wasp richness, abundance and taxonomic composition (at family level) were compared between plantations, and among habitats within plantations. Wasps were sampled using Malaise and Moericke traps. A total of 25,951 parasitoid wasps (10,828 in the conventional, and 15,123 in the organic crop area) were collected, and were distributed in 11 superfamilies and 38 families. In the conventional management area, the greatest abundance and richness of parasitoids were recorded in the adjacent forest, while, in the organic management area, the greatest abundance and richness were recorded in the crop-forest edge. Parasitoid wasp family richness was not influenced by management system and habitat but varied significantly between trap types. Average wasp abundance varied significantly between management systems. The presence of adjacent forest in both cultivation areas likely contributed to a greater abundance and richness of parasitoid wasps, showing the importance of preserving forest areas near the plantations. (AU)

Biomasa microbiana y respiración basal del suelo bajo sistemas agroforestales con cultivos de café / Microbial biomass and basal soil respiration under agroforestry systems with coffee crops

RESUMEN La actividad microbiológica es esencial para mantener la calidad de los suelos y los sistemas agroforestales surgen como alternativa, para el manejo agroecológico y sostenible del suelo. Este estudio evaluó el efecto de las variedades de café (Caturra y Catuaí) y de las fluctuaciones por épocas climáticas, sobre algunas propiedades microbiológicas del suelo, como indicadores de calidad, en un sistema agroforestal. Las muestras de suelo, se tomaron en la capa superior, a 5cm de profundidad, durante un año en épocas seca y lluviosa. Las mayores emisiones de CO2, se observaron en los suelos con la variedad Catuaí, en época seca. Los niveles de carbono de la biomasa microbiana (Cmic) no mostraron diferencias entre las variables estudiadas. Los valores obtenidos para el cociente metabólico (qCO2) fueron mayores en los suelos con la variedad Catuaí, mientras que el cociente microbiano (qMic) presentó los mayores valores en los suelos con la variedad Caturra. El cociente de eficiencia metabólica (qCO2.Corg -1) no mostró diferencias entre los suelos estudiados; sin embargo, sus niveles fueron más altos para las muestras tomadas durante la época seca. La microbiota del suelo denotó sensibilidad a los cambios por época climática de muestreo y tipo de variedad cultivada, mientras que las constantes ecofisiológicas resultaron sensiblemente apropiadas, para evaluar la calidad del suelo.

ABSTRACT The microbiological activity is essential to maintain soil quality, and agroforestry systems emerge as an alternative to the agro-ecological and sustainable land management. This work evaluated the effect of the Caturra and Catuaí coffee varieties, and the weather fluctuation on some microbiological properties of the soil, as indicators of quality in an agroforestry system. The soil samples were taken from the top layer with a depth of 5cm, during a year in dry and rainy seasons. The highest CO2 emissions were observed in soils with the Catuaí variety, in the dry season. On the other hand, Carbon levels of the microbial biomass (Cmic) did not show differences between the variables studied. The values obtained for the metabolic quotient (qCO2) were higher in soils with the Catuaí variety; while the microbial quotient (qMic) presented the highest values in soils with the Caturra variety. The metabolic efficiency ratio (qCO2.Corg-1) showed no differences between the studied soils, however, their levels were higher for the samples taken during the dry season. Soil microbiota showed sensitivity to changes by climatic period and by the type of variety, while the constant eco-physiological were substantially appropriate to evaluate soil quality and sensitive to changes by climatic period and variety of coffee grown in these agroecosystems.

Human-modified landscape acts as refuge for mammals in Atlantic Forest / Paisagem antropicamente modificada atua como refúgio para mamíferos na Mata Atlântica

Abstract: Human-modified landscapes (HMLs) are composed by small, isolated and defaunated forest fragments, which are surrounded by agricultural and urban areas. Information on species that thrives in these HMLs is essential to direct conservation strategies in local and regional scales. Since HMLs are dominant in the Atlantic Forest, we aimed to assess the mammalian diversity in a HML in southeastern Brazil and to propose conservation strategies. We collected data of terrestrial (small-, medium- and large-sized) and volant mammals in three small forest fragments (10, 14 and 26 ha) and adjacent areas, between 2003 and 2016, using complementary methods: active search, camera trapping, live-traps, mist nets and occasional records (i.e., roadkills). In addition, we used secondary data to complement our species list. We recorded 35 native mammal species (6 small-sized, 16 medium- and large-sized, and 13 bats) and seven exotic species in the HML. The recorded mammal assemblage (non-volant and volant), although mainly composed of common and generalist species, includes three medium- and large-sized species nationally threatened (Leopardus guttulus, Puma concolor and Puma yagouaroundi) and two data deficient species (Galictis cuja and Histiotus velatus), highlighting the importance of this HML for the maintenance and conservation of mammal populations. Despite highly impacted by anthropogenic disturbances, the study area harbors a significant richness of medium- and large-sized mammals, being an important biodiversity refuge in the region. However, this biodiversity is threatened by the low quality of the habitats, roadkills and abundant populations of domestic cats and dogs. Therefore, we stress the need of conservation strategies focusing on the medium- and large-sized mammals as an umbrella group, which could benefit all biodiversity in the landscape. We recommend actions that promotes biological restoration, aiming to increase structural composition and connectivity of the forest fragments, reducing roadkills and controlling the domestic cats and dogs' populations, in order to maintain and improve the diversity of mammals in long-term.

Resumo: Paisagens antropicamente modificadas (HMLs) são compostas por fragmentos florestais pequenos, isolados e defaunados, imersos em áreas agrícolas e/ou urbanas. Informações sobre as espécies que habitam essas paisagens são importantes para o direcionamento de estratégias de conservação em escalas local e regional. Uma vez que as HMLs são as paisagens dominantes na Mata Atlântica, o objetivo deste trabalho foi avaliar a diversidade de mamíferos em uma HML do sudeste do Brasil e propor estratégias para sua conservação. Foram coletados dados de mamíferos terrestres (pequenos, médios e grandes) e voadores em três fragmentos florestais (10, 14 e 26 ha) e áreas adjacentes, entre 2003 e 2016, usando métodos complementares: busca ativa, armadilhamento fotográfico, armadilhas de captura e redes de neblina. Adicionalmente, foram utilizados dados de literatura para complementar a lista de espécies. Foram registradas 35 espécies de mamíferos nativos (6 de pequenos, 16 de médios e grandes e 13 de morcegos) e sete espécies exóticas. A assembleia de mamíferos registrada (terrestres e voadores), embora composta por espécies generalistas, apresentou três espécies de médio e grande porte ameaçadas de extinção nacionalmente (Leopardus guttulus, Puma concolor and Puma yagouaroundi) e duas deficientes em dados (Galictis cuja and Histiotus velatus), destacando a importância dessa HML para conservação e manutenção das populações de mamíferos. Embora inserida em uma paisagem extremamente modificada, a área de estudo abriga uma riqueza significativa de mamíferos de médio e grande porte, sendo um importante refúgio para a biodiversidade na região. Entretanto, essa biodiversidade está ameaçada pela baixa qualidade dos habitats, por atropelamentos e por abundantes populações de cães e gatos domésticos. Portanto, enfatizamos a necessidade de estratégias de conservação focadas nos mamíferos de médio e grande porte como grupo "guarda-chuva", o que pode beneficiar as demais espécies na paisagem. Recomendamos ações de conservação visando a restauração biológica, para melhorar a composição estrutural e conectividade dos fragmentos florestais, reduzir o número de atropelamentos e controlar as populações de cães e gatos domésticos, afim de manter e aumentar a diversidade local de mamíferos em longo prazo.

High species richness of native pollinators in Brazilian tomato crops / Alta riqueza de espécies de polinizadores nativos em plantações Brasileiras de tomateiro

Abstract Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp.) are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the study agroecosystem.

Resumo Polinizadores fornecer um serviço essencial para os ecossistemas naturais e para agricultura. Em tomateiros, as anteras são poricidas e o pólen pode sair a partir dos poros quando as flores são agitadas pelo vento. No entanto, as abelhas que vibram as anteras aumentam a carga de pólen no estigma e na produção de frutos. O presente estudo teve como objetivo identificar a riqueza dos polinizadores das flores de tomate e investigar suas características morfológicas e funcionais relacionadas com a interação planta-polinizador em plantações do Brasil central. Foram registrados o tempo de antese, duração flor, bem como o número e viabilidade de grãos de pólen e óvulos. Os visitantes florais foram observados e coletados. Os botões florais abriram-se em torno 06h30 e fechou em torno de 18h00. As flores reabrem no dia seguinte ao mesmo tempo na parte da manhã, com longevidade média de 48 horas. A maior disponibilidade de pólen ocorreu durante as primeiras horas da antese. Depois disso, o número de grãos de pólen diminuiu, especialmente entre as 10h00 às 12h00, o que é consistente com os padrões de visitação de polinizadores. Quarenta espécies de abelhas foram encontradas nos campos de tomate, 30 das quais foram consideradas polinizadores. Durante o período de floração, as plantas oferecem enorme quantidade de pólen para os seus visitantes. Isto pode explicar a alta riqueza e quantidade de abelhas que visitam as flores de tomate nas áreas de estudo. O período de disponibilidade e redução de pólen durante todo o período do dia é sobreposto com o período de alimentação das abelhas, o que sugere que elas são altamente eficazes na remoção de grãos de pólen das anteras. Muitos desses grãos provavelmente são depositados no estigma da mesma flor, levando à auto-polinização e o desenvolvimento de frutos. Abelhas nativas (Exomalopsis spp.) são polinizadores efetivos de flores de tomate, podendo contribuir para o aumento da produtividade das culturas. Por outro lado, as flores de tomate oferecem grandes quantidades de pólen de recursos para uma alta riqueza e quantidade de abelhas, que mostram um estudo forte interação planta-polinizador nos agroecossistemas.

First record of Peckia (Sarcodexia) lambens (Wiedemann, 1830) (Diptera: Sarcophagidae) parasitizing Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) in Brazil / Primeiro registro de Peckia (Sarcodexia) lambens (Wiedemann, 1830) (Diptera: Sarcophagidae) parasitando Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) no Brasil

Collections of larvae of Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) carried out in the field in three localities in the city of Campo Grande, Mato Grosso do Sul, Brazil, from October 2012 to March 2014, recorded the presence of three species of Diptera parasitizing Spodoptera frugiperda: two species of Tachinidae, Achytas incertus (Macquart, 1851) and Winthemia trinitatis Thompson, 1963, and one species of Sarcophagidae, Peckia (Sarcodexia) lambens (Wiedemann, 1830). The latter is identified for the first time parasitizing S. frugiperda in Brazil.(AU)

Coletas de larvas de Spodoptera frugiperda (Smith, 1797) (Lepidoptera: |Noctuidae) realizadas no campo em três localidades da cidade de Campo Grande, Mato Grosso do Sul, Brasil, entre outubro de 2012 e março de 2014, registraram a presença de três espécies de Diptera como parasitoide de S. frugiperda: duas espécies de Tachinidae, Archytas incertus (Macquart, 1851) e Winthemia trinitatis Thompson, 1963, e uma espécie de Sarcophagidae, Peckia (Sarcodexia) lambens (Wiedemann 1830), sendo esta identificada pela primeira vez no país como parasitoide larval de S. frugiperda.(AU)

Use of functional traits to assess changes in stream fish assemblages across a habitat gradient

Functional traits are important for understanding the links between species occurrence and environmental conditions. Identifying these links makes it possible to predict changes in species composition within communities under specific environmental conditions. We used functional traits related to habitat use and trophic ecology in order to assess the changes in fish community composition between streams with varying habitat structure. The relationship between the species traits and habitat characteristics was analyzed using an RLQ ordination analysis. Although species were widely distributed in habitats with different structures, physical conditions did favor some species based on their functional characteristics. Eight functional traits were found to be associated with stream habitat structure, allowing us to identify traits that may predict the susceptibility of fish species to physical habitat degradation.

Os atributos funcionais são importantes para entender a ligação entre ocorrência das espécies e condições ambientais, permitindo predizer sobre as mudanças na composição de espécies em comunidades submetidas a condições ambientais específicas. Utilizamos atributos funcionais relacionados com o uso de habitat e ecologia trófica para avaliar as mudanças na composição de espécies de peixes em riachos com diferenças na estrutura física. O relacionamento entre os atributos das espécies e as variáveis ambientais foi avaliado por meio da análise de ordenação RLQ. Embora algumas espécies tenham sido amplamente distribuídas em hábitats com diferentes características, outras foram restritas por essas condições e este relacionamento está associado com as características morfológicas. Oito atributos funcionais foram capazes de detectar as variações na estrutura física do hábitat em riachos, permitindo a identificação de atributos que podem predizer a suscetibilidade das espécies de peixes para a degradação física do hábitat.

First report of Dolichozele koebeleiViereck, 1911 (Hymenoptera: Braconidae) on larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) in maize (Zea maysL.) under different cropping systems

In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea maysL.). However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) in Spodoptera frugiperda(J. E. Smith, 1797) (Lepidoptera: Noctuidae) larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106). In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

No contexto agrícola moderno, o controle de pragas é importante para se obter aumento de produtividade na cultura do milho (Zea mays L.). No entanto, esse controle deve ser feito racionalmente, e deve priorizar métodos ambientalmente mais seguros, como o controle biológico. Este trabalho teve como objetivo relatar a ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho sob diferentes formas de cultivo. O experimento foi conduzido no Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) em Sete Lagoas, Minas Gerais, Brasil, em áreas de produção orgânica e convencional. Durante todo o ciclo do milho (cultivar BR 106), três vezes por semana, foram amostradas em cada uma das 24 parcelas, 10 plantas, que foram avaliadas no laboratório. As larvas encontradas foram distribuídas individualmente em recipientes de criação com dieta artificial até o final do ciclo biológico. Maior número de larvas de S. frugiperda foi obtido no milho orgânico solteiro, com maior percentual de larvas de S. frugiperda parasitadas por Hymenoptera ou Diptera. Dolichozele koebelei ainda não havia sido descrita em associação com larvas de S. frugiperda. De uma forma geral nos dois experimentos o percentual de larvas de S. frugiperda parasitadas, foi alto, indicando a importância dos agentes de controle natural na redução da densidade populacional de S. frugiperda e, principalmente, a importância do manejo adequado da cultura do milho.

First report of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) on larvae of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) in maize (Zea mays L.) under different cropping systems / Primeira ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho (Zea mays L.) sob diferentes formas de cultivo

In the context of the modern agriculture, pest control is important in order to increase productivity in maize (Zea mays L.). However, this control should be done rationally, prioritising environmentally safer methods such as biological control. This paper aims to report the occurrence of Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) larvae collected in maize subjected to different cropping systems. The experiment was conducted at the Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) in Sete Lagoas, Minas Gerais State, Brazil, using organic and conventional production. Ten plants were sampled from each of the 24 plots and for each production system, three times a week during the entire cycle of maize (variety BR 106). In the laboratory, larvae were distributed in individual rearing containers with artificial diet until the end of the biological cycle. An increased number of S. frugiperda larvae was observed in organic single crop maize; hence a higher percentage of S. frugiperda larvae parasitised by Hymenoptera and Diptera also occurred in the maize under this production system. Dolichozele koebelei had not yet been described in association with larvae of S. frugiperda. The percentage of parasitism of S. frugiperda larvae was high in both experiments, indicating the importance of natural control agents in reducing the population density of S. frugiperda, and especially the importance of an appropriate crop management.

No contexto agrícola moderno, o controle de pragas é importante para se obter aumento de produtividade na cultura do milho (Zea mays L.). No entanto, esse controle deve ser feito racionalmente, e deve priorizar métodos ambientalmente mais seguros, como o controle biológico. Este trabalho teve como objetivo relatar a ocorrência de Dolichozele koebelei Viereck, 1911 (Hymenoptera: Braconidae) em larvas de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) coletadas em milho sob diferentes formas de cultivo. O experimento foi conduzido no Centro Nacional de Pesquisa de Milho e Sorgo (CNPMS) em Sete Lagoas, Minas Gerais, Brasil, em áreas de produção orgânica e convencional. Durante todo o ciclo do milho (cultivar BR 106), três vezes por semana, foram amostradas em cada uma das 24 parcelas, 10 plantas, que foram avaliadas no laboratório. As larvas encontradas foram distribuídas individualmente em recipientes de criação com dieta artificial até o final do ciclo biológico. Maior número de larvas de S. frugiperda foi obtido no milho orgânico solteiro, com maior percentual de larvas de S. frugiperda parasitadas por Hymenoptera ou Diptera. Dolichozele koebelei ainda não havia sido descrita em associação com larvas de S. frugiperda. De uma forma geral nos dois experimentos o percentual de larvas de S. frugiperda parasitadas, foi alto, indicando a importância dos agentes de controle natural na redução da densidade populacional de S. frugiperda e, principalmente, a importância do manejo adequado da cultura do milho.

Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems

The composition and seasonal occurrence of sandflies were investigated in coffee agroecosystems in the Soconusco region of Chiapas, Mexico. Insect sampling was performed on three plantations located at different altitudes: Finca Guadalupe Zajú [1,000 m above sea level (a.s.l.)], Finca Argovia (613 m a.s.l.) and Teotihuacán del Valle (429 m a.s.l.). Sandflies were sampled monthly from August 2007-July 2008 using three sampling methods: Shannon traps, CDC miniature light traps and Disney traps. Sampling was conducted for 3 h during three consecutive nights, beginning at sunset. A total of 4,387 sandflies were collected during the course of the study: 2,718 individuals in Finca Guadalupe Zajú, 605 in Finca Argovia and 1,064 in Teotihuacán del Valle. The Shannon traps captured 94.3% of the total sandflies, while the CDC light traps and Disney traps captured 4.9% and 0.8%, respectively. More females than males were collected at all sites. While the number of sandflies captured was positively correlated with temperature and relative humidity, a negative correlation was observed between sandfly numbers and rainfall. Five species of sandflies were captured: Lutzomyia cruciata , Lutzomyia texana , Lutzomyia ovallesi , Lutzomyia cratifer / undulata and Brumptomyia sp. Lu. cruciata , constituting 98.8% of the total, was the most abundant species. None of the captured sandflies was infected with Leishmania spp.

Rodentborne fungal pathogens in wetland agroecosystem

The past few decades have witnessed an overwhelming increase in the incidence of fungal infections, particularly in immunocompromised individuals. Consequently, zoonotic diseases, especially through rodents constitute a prominent group among the emerging diseases. Rodents are commensal to man and related health risks are common. Water rats (Rattus norvegicus) are typical to Vembanadu-Kol wetland agroecosystems, where they can act as a good carrier nexus for pathogens. The present study evaluates the carrier status of water rats with respect to fungal pathogens. A total of fifty two fungi covering eighteen families were isolated. Among the isolates, eight were dermaptophytes and Chrysosporium sp. (89.18%) was the frequent isolate. The source-wise analyses showed an increased isolation from ventral hair (67 isolates). Water rats of Vembanadu-Kol wetland agroecosystem are potent carrier of dermaptophytes and other opportunistic fungi, and strong carrier paths are existing too.

Can rice field channels contribute to biodiversity conservation in Southern Brazilian wetlands?

Conservation of species in agroecosystems has attracted attention. Irrigation channels can improve habitats and offer conditions for freshwater species conservation. Two questions from biodiversity conservation point of view are: 1) Can the irrigated channels maintain a rich diversity of macrophytes, macroinvertebrates and amphibians over the cultivation cycle? 2) Do richness, abundance and composition of aquatic species change over the rice cultivation cycle? For this, a set of four rice field channels was randomly selected in Southern Brazilian wetlands. In each channel, six sample collection events were carried out over the rice cultivation cycle (June 2005 to June 2006). A total of 160 taxa were identified in irrigated channels, including 59 macrophyte species, 91 taxa of macroinvertebrate and 10 amphibian species. The richness and abundance of macrophytes, macroinvertebrates and amphibians did not change significantly over the rice cultivation cycle. However, the species composition of these groups in the irrigation channels varied between uncultivated and cultivated periods. Our results showed that the species diversity found in the irrigation channels, together with the permanence of water enables these man-made aquatic networks to function as important systems that can contribute to the conservation of biodiversity in regions where the wetlands were converted into rice fields. The conservation of the species in agriculture, such as rice field channels, may be an important alternative for biodiversity conservation in Southern Brazil, where more than 90% of wetland systems have already been lost and the remaining ones are still at high risk due to the expansion of rice production. Rev. Biol. Trop. 59 (4): 1895-1914. Epub 2011 December 01.

La conservación de especies en los agroecosistemas ha llamado la atención. Los canales de riego pueden mejorar los hábitats y ofrecer condiciones para la conservación de especies de agua dulce. Desde el punto de vista de conservación de la biodiversidad surgen dos preguntas: 1) ¿Pueden los canales de riego mantener una rica diversidad de vegetación acuática, invertebrados y anfibios en el ciclo de cultivo del arroz? 2) ¿Puede la riqueza, abundancia y composición de especies acuáticas cambiar durante el ciclo de cultivo del arroz? Para ello, en el Condado Mostardas, Brazil un grupo de cuatro canales de los campos de arroz fue seleccionado al azar. En cada canal, se llevaron a cabo seis muestreos durante el ciclo de cultivo del arroz (junio 2005 hasta junio 2006). Un total de 160 táxones fueron identificados en los canales de riego, que incluyen 59 especies de macrófitos, 91 táxones de macroinvertebrados y 10 especies de anfibios. La riqueza y la abundancia de vegetación acuática, invertebrados y anfibios no cambió significativamente durante el ciclo de cultivo del arroz. Sin embargo, la composición de las especies de estos grupos en los canales de riego varía entre períodos no cultivados y cultivados. Nuestros resultados muestran que la diversidad de especies en los canales de riego, junto con la permanencia del agua permite que estas redes acuáticas provocadas por el ser humano puedan funcionar como sistemas importantes que contribuyan con la conservación de la biodiversidad en las regiones donde los humedales se han convertido en campos de arroz. La conservación de las especies en la agricultura, tales como los campos de los canales de arroz, que pueden ser una alternativa importante para la conservación de la biodiversidad en el sur de Brasil, donde más del 90% de los sistemas de humedales ya se han perdido y los restantes aún se encuentran en alto riesgo debido a la expansión de la producción de arroz.

Avaliação rápida da diversidade de formigas em sistemas de uso do solo no sul da Bahia / Rapid evaluation of ant diversity in land use systems in southern Bahia, Brazil

We aimed to compare the soil ant diversity in different land use systems from Atlantic Forest area, in Southern Bahia state, Brazil. The ants were sampled in 16 sites: two primary forest sites (un-logged forest); three young secondary forests (<8 years old); three intermediate secondary forests (8-20 years old); three old secondary forests (>20 years old); three Eucalyptus grandis plantations (3-7 years old), and two introduced pastures. Each site was sampled in three sampling points 15 m apart, and distant over 50 m from the site edge. In each sampling point we gathered the litter from a 1 m² and extracted the ants with Winkler extractors during 48h. We found 103 ant species from 29 genera and eight subfamilies. The five richest genera were Pheidole (19 species), Solenopsis (8), Apterostigma (10), Hypoponera (7) e Paratrechina (5). The highest ant richness density was found in the primary forest (7.4 species/sample; S = 37; n = 5); followed by the old secondary forest (5.33 species/sample; S = 48; n = 9); young secondary forest (5.25 species/sample; S = 42, n = 8); eucalyptus plantation (4.22 species/sample; S = 38, n = 9), intermediate secondary forest (3.5 species/sample; S = 35, n = 10, and introduced pasture (2.67 species/sample; S = 16, n = 6). The ecosystems with higher structural complexity showed the highest ant richness density by sample. Therefore, in the Atlantic Forest region, the eucalyptus plantation is a better alternative of land use to conserve the ant biodiversity than pastures, and quite similar to native secondary forests in ant community characteristics.

Efeito da estrutura de habitat sobre a abundância de parasitóides Pseudacteon Coquillett (Diptera, Phoridae) em ninhos de Solenopsis invicta Buren (Hymenoptera, Formicidae) / Influence of habitat structure on the abundance of the parasitoids Pseudacteon Coquillett (Diptera, Phoridae) on mounds of Solenopsis invicta Buren (Hymenoptera, Formicidae)

A influência de características do habitat na abundância dos parasitóides Pseudacteon Coquillett (Diptera, Phoridae) de Solenopsis invicta Buren (Hymenoptera, Formicidae) foi estudada em um agroecossistema orgânico diversificado no sudeste do Brasil. Os parasitóides foram coletados durante 30 minutos após a perturbação de ninhos da formiga lava-pé em áreas com culturas anuais ou perenes. Foram coletados no total 228 parasitóides de quatro espécies diferentes em 61,90 por cento dos 84 ninhos da formiga lava-pé perturbados. Pseudacteon obtusus Borgmeier foi a espécie mais abundante (70 fêmeas), seguida por Pseudacteon litoralis Borgmeier (37 fêmeas), Pseudacteon tricuspis Borgmeier (23 fêmeas) e Pseudacteon solenopsidis Schmitz (1 fêmea). Pseudacteon litoralis foi mais freqüente em ninhos presentes nas culturas perenes que anuais enquanto que P. obtusus e P. tricuspis tiveram um padrão oposto. Correlações significativamente negativas foram encontradas para as abundâncias de P. litoralis e P. obtusus com a temperatura do ar. Houve correlação significativamente positiva entre a abundância dos parasitóides e o tamanho dos ninhos da formiga lava-pé. Considerando que os forídeos são importantes inimigos naturais de S. invicta, esse estudo fornece informações para o manejo de S. invicta em agroecossistemas tropicais diversificados.

The influence of habitat characteristics on the abundance of the parasitoids Pseudacteon Coquillett (Diptera, Phoridae) of Solenopsis invicta Buren (Hymenoptera, Formicidae) was studied in organic polyculture agroecosystem in southeastern of Brazil. Parasitoids were collected during 30 minutes after fire ant colonies perturbation in plots with annual or perennial crops. A total of 228 parasitoids belonging to four species were obtained in 61.90 percent of the 84 fire ant colonies disturbed. Pseudacteon obtusus Borgmeier was the most abundant species (70 females), followed by Pseudacteon litoralis Borgmeier (37 females), Pseudacteon tricuspis Borgmeier (23 females) and Pseudacteon solenopsidis Schmitz (1 female). Pseudacteon litoralis was more frequent on fire ant mounds in plots with perennial crops than annual crops whereas P. obtusus and P. tricuspis had an opposed pattern. Negative significant correlation was found between air temperature and P. litoralis and P. obtusus abundances. Fire ant mound size and parasitoid abundance were positively correlated. Considering that phorids are important natural enemies of S. invicta, this study provides information for the management of fire ants in tropical polyculture agroecosystem.

Water use in four model tropical plant associations established in the lowlands of Costa Rica

We examined soil water use patterns of four model plant associations established in the North Caribbean lowlands of Costa Rica by comparing the stable hydrogen isotope composition, δD, in xylem sap and in soil water at different depths, under rainy and dry conditions. Four 5-year-old model plant associations composed of 2 tree species (Hyeronima alchorneoides and Cedrela odorata) having different architecture and phenology were studied. Average tree height was 8.9 and 7.6 m, respectively. Each tree species was grown in monoculture and in polyculture with 2 perennial monocotyledons (Euterpe oleracea and Heliconia imbricata). Maximum rooting depth at the time of δD determination was ~ 2 m for almost all species. Most roots of all species were concentrated in the upper soil layers. Stomatal conductance to water vapor (gS) was higher in the deciduous C. odorata than in the evergreen H. alchorneoides; within each species, gS did not differ when the trees were grown in mono or in polyculture. During the rainy season, gradients in soil water δD were not observed. Average rainy season xylem sap δD did not differ among members of the plant combinations tested (-30 ‰), and was more similar to δD values of shallow soil water. Under dry conditions, volumetric soil water content declined from 50 to ~ 35%, and modest gradients in soil water δD were observed. xylem sap δD obtained during dry conditions was significantly lower than rainy season values. xylem sap δD of plants growing in the four associations varied between -9 and -22‰, indicating that shallow water was predominantly absorbed during the dry period too. Differences in xylem sap δD of trees and monocots were also detected, but no significant patterns emerged. The results suggest that: a) the plant associations examined extracted water predominantly from shallow soil layers (<1 m), b) the natural isotopic variation in soil and plant water at the study site was low, and c) the plant mixes obtain water from more than a single soil layer simultaneously. Temporal factors were important in determining the competition and complementary relations observed among the trees and the perennial monocots. Under the prevailing environmental conditions, water use in these plant associations was determined largely by species-specific attributes such as biomass allocation to fine roots, phenology, and canopy architecture, and to a lesser extent by water limitations. Rev. Biol. Trop. 56 (4): 1947-1957. Epub 2008 December 12.

Examinamos los patrones de uso de agua del suelo de cuatro asociaciones vegetales establecidas en el Caribe norte de Costa Rica, comparando la composición isotópica del hidrógeno, δD, en la savia del xilema y en el agua del suelo en condiciones lluviosas y secas. Estudiamos cuatro asociaciones de cinco años de edad compuestas por dos árboles (Hyeronima alchorneoides y Cedrela odorata) con diferente arquitectura y fenología, cultivados en mono y policultivo con dos monocotiledóneas perennes (Euterpe oleracea y Heliconia imbricata). Las excavaciones mostraron que la profundidad máxima de las raíces fue de 2 m para casi todas las especies, y que la mayor densidad de raíces se encontraba en la superficie del suelo. La conductividad estomática (gS) fue mayor en el árbol caducifolio (C. odorata) que en el perennifolio (H. alchorneoides); dentro de cada especie, gS no difirió cuando los árboles fueron cultivados en mono o en policultivo. Los resultados sugieren que: a) las asociaciones examinadas extrajeron agua predominantemente de las capas superficiales del suelo (<1 m), b) la variación natural en el acceso al agua del suelo por parte de las especies, y en las propiedades del suelo, fue baja, y c) las combinaciones de plantas obtuvieron agua de varias capas del perfil del suelo simultáneamente. Los factores relacionados con el tiempo fueron importantes en la determinación de las relaciones de competencia y complementariedad observadas entre los árboles y las monocotiledóneas perennes. En las condiciones ambientales prevalecientes, el uso del agua por parte de estas asociaciones de plantas fue determinado más por atributos, como la asignación de biomasa a las raíces finas, la fenología, y las propiedades del dosel, que por limitaciones en la disponibilidad de agua.

What is the effect of soil use on ant communities? / Qual é o efeito do uso do solo sobre as comunidades de formigas?

Studies on ant communities in agroecosystems have contributed to the knowledge of the effect of agricultural activities on biological communities. The aim of this study is to explain the effect of soil use on ant communities. We tested the hypothesis that there was a decrease in ant species richness and a change in the species composition at habitats with more intense soil use. We collected ants using sardine baits, subterranean traps and direct sampling at four habitats with different soil use (secundary forest, Acacia forestry, initial stage of succession and mixed crops). The ant species richness did not decrease with intensity of soil use. In successional habitat the species numbers collected using sardine baits and subterranean traps were significantly different. Species composition of communities had a pronounced variation, with the epigaeic and hypogaeic ant faunas of the habitat with high intense soil use (mixed crops) had low similarity with ant communities of the three other habitats. The predator species were restricted to habitats with low intensity of soil use. Then, species composition could better reflect the functional changes on ant communities than species richness. Our data can help to choose the component of ant community that better reflect the response of biodiversity to agricultural impacts.

Estudos sobre as comunidades de formigas em agroecossistemas têm contribuído para o conhecimento do efeito das práticas agrícolas sobre as comunidades biológicas. O objetivo deste trabalho foi avaliar o efeito do uso do solo nas comunidades de formigas. Foi testada a hipótese de que há um decréscimo na riqueza de espécies de formigas e uma mudança na composição de espécies em habitats com uso mais intenso do solo. As formigas foram amostradas com iscas de sardinhas, armadilhas subterrâneas e por coleta direta em quatro habitats com diferentes usos do solo (mata secundária, início de sucessão vegetal, reflorestamento com Acacia e cultivo misto). A riqueza não diminuiu com a intensidade de uso do solo. Na área em início de sucessão vegetal, o número de espécies coletadas por iscas de sardinha foi significativamente diferente do obtido pelas armadilhas subterrâneas. A composição de espécies teve uma pronunciada variação, sendo que a fauna de formigas epigéica e hipogéica do habitat com maior intensidade de uso do solo (cultivo misto) mostrou baixa similaridade com as comunidades de formigas dos outros três habitats. As espécies predadoras restringiram-se aos habitats com baixa intensidade de uso do solo (mata secundária e sucessão vegetal). Assim, a composição de espécies refletiu melhor as mudanças funcionais nas comunidades de formigas ao uso do solo do que a riqueza de espécies. Os resultados podem ajudar a escolher o componente das comunidades de formigas mais adequado e que melhor corresponde à resposta da biodiversidade aos impactos causados pelas atividades agrícolas.