Habitat loss and fragmentation are considered the major threat to biodiversity at global scale. The main driving force behind this process is agricultural intensification that is based on pesticide overuse and expansion of monocultures resulting in landscape simplification as well as loss of species and associated ecosystem services. Despite recognized importance, little is known about how agricultural intensification affects the occurrence of different insect functional groups at multiple spatial scales in the Neoptropical region. The aim of this study is investigate how landscape structure and local factors (e.g. microclimate and pesticides) affect insect community and the provision of ecosystem services and disservices in crop matrix. For this, wasps (natural enemies), bees and flower flies (pollinators) were collected in 16 coffee plantations and in 16 forest fragments located in different landscape contexts in southeast Brazil. Moreover, the abundance of the coffee leaf miner Leucoptera coffeella (pest) and mortality rates related to predation (biological control) were estimated within coffee plantations. Landscape structure was represented by the following metrics: percentage of forest cover, landscape diversity and edge. These metrics were calculated at four spatial scales 250, 500, 750 and 1000 meters in the surroundings 0of coffee-forest interfaces. Over 13 months, we collected 13,658 wasps distributed in 86 species and 26 genres; 8,393 bees belonging to 116 species and 73 genres; and 4,984 flower flies within 63 species and 20 genres. Pest abundance and biological control varied from 5.3 to 32.5 % and from 12.7 to 72.8 %, respectively. Pest abundance was negatively correlated with the increment of forest cover and decreasing temperature. Species richness and abundance of wasps and bee species richness increased with increasing forest cover. The beta diversity of wasps and bees presented high values of nested component between pairs of interfaces located in landscapes with high and low forest cover indicating species loss in structurally simple landscapes dominated by monocultures. These results were found at all spatial scales from 250 to 1000 meters suggesting that forest conservation and restoration can enhance the balance between crop production and biodiversity conservation, and that it should be promoted at landscape scale. Increasing forest cover in crop dominated landscapes can result in higher availability of resources resulting in the high species diversity and provision of associated ecosystem services such as pollination and pest biological control. / A fragmentação e perda de habitats são consideradas as maiores ameaças à biodiversidade em escala global. A principal força condutora desses processos é a intensificação da agricultura, que se baseia no uso excessivo de pesticidas e expansão das monoculturas, resultando na simplificação da paisagem e na perda de espécies e de serviços ecossistêmicos associados a eles. Apesar da reconhecida importância, pouco se sabe sobre como a intensificação da agricultura afeta a ocorrência de diferentes grupos funcionais de insetos em múltiplas escalas espaciais na região Neotropical. Nesse contexto, o objetivo deste estudo foi analisar como a estrutura da paisagem e fatores locais (ex. microclima, pesticidas) afetam a comunidade de insetos e a provisão de serviços e desserviços na matrix agrícola. Para tanto, vespas (inimigos naturais), abelhas e sirfídeos (polinizadores) foram coletados em 16 plantações de café e em 16 fragmentos florestais adjacentes, situados em diferentes contextos de paisagem na região Sudeste do Brasil. Além disso, a abundância do inseto praga Leucoptera coffeella e sua taxa de mortalidade relacionada à predação (controle biológico) foram estimadas no interior dos cafezais. A estrutura da paisagem foi representada pelas métricas: porcentagem de cobertura florestal, diversidade da paisagem e densidade de bordas. Elas foram calculadas em quatro escalas espaciais: 250, 500, 750 e 1000 metros, no entorno das interfaces café-floresta. Dentre os resultados, destacamos que ao longo de 13 meses foram coletadas 13658 vespas - distribuídas em 86 espécies e 26 gêneros; 8393 abelhas - distribuídas em 116 espécies 73 gêneros; e 4984 sirfídeos - compreendendo 63 espécies e 20 gêneros. A abundância da praga e o controle biológico variaram de 5.3 a 32.5 % e de 12.7 a 72.8 %, respectivamente. A abundância de L. coffeella apresentou correlação negativa com o aumento de cobertura florestal e diminuição da temperatura. A riqueza de espécies e abundância de vespas e a riqueza de espécies de abelhas aumentaram com o incremento da cobertura florestal. A diversidade beta de vespas e abelhas apresentaram altos valores do componente \"nested\" entre pares de interfaces localizadas em paisagens com alta e baixa cobertura florestal, indicando a perda de espécies em paisagens simplificadas dominadas por monoculturas. Esses resultados foram encontrados em todas as escalas espaciais, entre 250 e 1000 metros, sugerindo que a conservação e restauração florestal podem melhorar o balanço entre a produção agrícola e a conservação da biodiversidade e que devem ser implantadas em escala de paisagem. O aumento de cobertura florestal em paisagens estruturalmente simplificadas pode aumentar a disponibilidade de recursos resultando no aumento de diversidade de espécies e da provisão de serviços ecossistêmicos como a polinização e o controle biológico de pragas.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A Caatinga à a vegetaÃÃo predominante no semiÃrido Nordestino, caracterizada por plantas caducifÃlias que perdem suas folhas durante o perÃodo de estiagem. Uma das prÃticas que vem contribuindo para a perda da diversidade à a exploraÃÃo indiscriminada da vegetaÃÃo natural para produÃÃo de lenha, cujos efeitos sÃo devastadores, principalmente, no bioma que à considerado um dos mais frÃgeis. Visando a exploraÃÃo da madeira de forma legalizada e sustentÃvel, a partir de 2012 foram aprovados Planos de Manejo Florestal. Para garantir a sustentabilidade do Plano de Manejo Florestal se faz necessÃrio a realizaÃÃo de pesquisas que avaliem os possÃveis impactos sobre os artrÃpodes de solo, uma vez que esses organismos reagem rapidamente a qualquer alteraÃÃo ocorrida dentro de um ambiente. Diante do exposto o presente trabalho tem por objetivo relatar informaÃÃes sobre os principais grupos de organismos habitantes do solo (ArtrÃpodes de solo ou edÃficos), bem como o efeito do plano de Manejo florestal sobre organismos presentes em uma Ãrea do bioma Caatinga. Foram selecionadas cinco Ãreas que adotam Plano de Manejo Florestal em diferentes estÃgios de sucessÃo (T1- Ãrea sem ser explorada à seis meses; T2- Ãrea sem ser explorada à 2-3 anos; T3- Ãrea sem ser explorada à 5-6 anos; T4- Ãrea sem ser explorada à 10-11 anos e; Te- Testemunha representada pela Ãrea de reserva legal (NÃo explorada), onde foram instaladas quatro armadilhas âPitfallâ em cada Ãrea. A partir dos artrÃpodes coletados foram calculados os Ãndices ecolÃgicos: Shannon-Weaver (Hâ) e o Ãndice de Uniformidade de Pielou (e), a riqueza de espÃcies e utilizada a anÃlise multivariada - AnÃlise de Componentes Principais (ACP). Constatou-se a presenÃa de diversas espÃcies de artrÃpodes que foram agrupados à nÃvel de Ordem, sendo encontrados de sete à 14 grupos. Constatou-se ainda que Acari, Collembola, Formicidae e Diptera foram os grupos mais representativos em quantidade e que o ciclo de 10 anos de exploraÃÃo da Caatinga seguindo o Plano de Manejo Florestal contribuiu para restauraÃÃo do ecossistema / Caatinga is the predominant vegetation in semi-arid ortheast of Brasil, characterized by deciduous plants that lose their leaves during the dry season. One of the practices that have contributed to the loss of diversity is the indiscriminate exploitation of natural vegetation for fuel wood, the effects are devastating, especially in the biome that is considered one of the weakest. Aiming to logging legalized and sustainable manner, from 2012 were approved Forest Management Plans. To ensure the sustainability of the forest management plan is necessary to conduct research to assess the possible impacts on soil arthropods, as these organisms react quickly to any change within an environment. Given the above the present study aims to report information on the major groups of organisms inhabitants of the soil (soil Arthropods or edaphic), as well as the effect of forest management plan on organisms present in an area of Caatinga. They selected five areas that adopt Forest Management Plan in different stages of succession (T1-area without being exploited to six months; T2-area without being exploited to 2-3 years; T3-area without being exploited to 5-6 years; T4-area without being exploited for 10-11 years; Te-Control represented by legal reserve area (not exploited), where 'Pitfall' were set four traps in each area from the arthropod cological indices were calculated: Shannon-Weaver (H') and the Uniformity Index Pielou (e), the species richness and used multivariate analysis. -Principal Component analysis (PCA) found the presence of several species of arthropods that were grouped to Order level, and found seven to 14 groups. It was also found that Acari, Collembola, Formicidae and Diptera were the most representative groups in quantity and the cycle of 10 years of exploration Caatinga following the Forest Management Plan has ecosystem restoration.

Surveys of plant and selected insect species was conducted in Highveld and Lowveld agro–ecosystems of four provinces of South Africa, namely North–West, Mpumalanga, KwaZulu–Natal and Limpopo. The objectives of the study were to compare insect and plant diversity between localities (grassland and savanna) and treatments (maize field, semi–transformed and untransformed) to test for a general relationship between plant and insect diversity along a maize field–field margin gradient. Plant and insect diversity patterns were studied along the gradient and quantified in terms of richness and diversity indices. Plant and insect species compositional turnover was also measured along the maize field–field margin gradient. Plant diversity increased with increasing distance from maize fields into the margin. The flora in maize fields and of margins differed, but in contrast, insect species assemblages were similar in maize fields and margins. There was no statistical difference in insect diversity between treatments (maize field, semi–transformed and transformed). A relationship was revealed between plant and insect diversity, as plant diversity enhanced insect diversity. / Thesis (M.Sc. (Environmental Sciences))--North-West University, Potchefstroom Campus, 2011.

Surveys of plant and selected insect species was conducted in Highveld and Lowveld agro–ecosystems of four provinces of South Africa, namely North–West, Mpumalanga, KwaZulu–Natal and Limpopo. The objectives of the study were to compare insect and plant diversity between localities (grassland and savanna) and treatments (maize field, semi–transformed and untransformed) to test for a general relationship between plant and insect diversity along a maize field–field margin gradient. Plant and insect diversity patterns were studied along the gradient and quantified in terms of richness and diversity indices. Plant and insect species compositional turnover was also measured along the maize field–field margin gradient. Plant diversity increased with increasing distance from maize fields into the margin. The flora in maize fields and of margins differed, but in contrast, insect species assemblages were similar in maize fields and margins. There was no statistical difference in insect diversity between treatments (maize field, semi–transformed and transformed). A relationship was revealed between plant and insect diversity, as plant diversity enhanced insect diversity. / Thesis (M.Sc. (Environmental Sciences))--North-West University, Potchefstroom Campus, 2011.

Thesis (PhD(Agric) (Conservation Ecology and Entomology))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: See full text document for abstract / AFRIKAANSE OPSOMMING: sien volteks dokument vir die opsomming

L’intérêt pour la dispersion des gènes via le pollen a augmenté avec les cultures de plantes génétiquement modifiées. A ce jour, les données expérimentales ainsi que la modélisation portant sur les mouvements du pollen de colza, Brassica napus L., à l’échelle du paysage ne différencie pas clairement la part du vent et des insectes dans cette dispersion. Cependant, l’estimation de la dispersion des gènes par le pollen reste une condition nécessaire pour la gestion des risques d’échappement des (trans-)gènes vers l’environnement et les cultures conventionnelles. A travers cette thèse, nous avons pu mettre en évidence qu’une grande diversité d’insectes pollinisateurs pouvait transporter du pollen viable entre différentes plantes de colza sur des distances importantes (>1.1 km). La diversité d’insectes varie d’une région à l’autre et d’une année sur l’autre. Cependant, bien que la majorité des insectes sur une zone de grande production de colza ait du pollen de cette culture sur leur corps, seulement 39,4 % des insectes capturés sur des plantes mâle-stériles transportent du pollen de colza viable. Bien que nous n’ayons pas pu déterminer avec précision la part du vent et des insectes dans le pollinisation du colza, il semblerait que les insectes participent de façon plus importante à la pollinisation de plantes présentes en bordures de champs, augmentant ainsi le taux de pollinisation croisée. Nos résultats fournissent des données fiables pour améliorer les modèles de dispersion pollinique pour des cultures entomophiles à l’échelle du paysage. Ces modèles sont essentiels pour l’aide à la gestion afin de réduire la dispersion des gènes par le pollen des cultures génétiquement modifiées vers les plantes sauvages ou les cultures conventionnelles / Interest in pollen-borne gene dispersal has grown with the cultivation of genetically modified plants. To date both experimental data and models of oilseed rape (OSR) Brassica napus pollen movement at the landscape scale do not clearly differentiate between wind- and insect-mediated dispersal. Estimations of pollen-borne gene dispersal would be valuable for managing potential escapes of transgenes. Our study provides clear evidence that a large variety of insect species can transfer viable pollen between oilseed rape plants over considerable distances (>1.1 km). Insect’s diversity according to geographical site and years. However, the majority of pollinator have OSR pollen in their body hairs, only 39.4% of the insects caught on male-sterile flowers carried OSR pollen. Although we could not determine with precision the role of the wind and the insects in the OSR pollination, it would seem that insects take part in a more important way in pollination of plants present in edges of fields, thus increasing cross pollination rate. Our results provide valuable data to improve models of pollen dispersal for entomophilous crops at the landscape scale. These models are essential to help land-managers reduce pollen-borne gene dispersal from genetically modified plants to wild relative and field planted with non-GM crops

No description available.

MSCAGR (Plant Production) / Department of Plant Production / Indigenous trees play important roles in livelihoods for rural communities. Sclerocarya birrea and Berchemia discolor are indigenous in Africa and are used in rural communities for food and livestock feed, as well as for medicinal and construction purposes. These trees are subject to attack by insects, which can result in lower tree productivity. However, there is no documented information about insects found on both tree species in South Africa. This study investigated the seasonal abundance and diversity of insects on S. birrea and B. discolor in Tshikundamalema Area, Limpopo Province, South Africa. Five trees were selected for each of the two tree species at two sampling sites with different vegetation cover, one site mainly the woodland bushveld while the other site was savannah grasslands. Canopy fogging was used to sample insects. Insect samples were collected at one time point for each of the seasons: summer (February), autumn (May), winter (July) and spring (November). Insects were identified to morphospecies and Simpson’s diversity index was used to compare insect diversity on both trees. Analysis of variance was used to compare the abundance of insects across seasons. The most abundant insects were collected from Coleoptera, followed by Hemiptera, Hymenoptera, Diptera, Lepidoptera and Orthoptera. A total of 3259 insects belonging to the six Orders were collected. All specimens belonging to Coleoptera, Hemiptera and Hymenoptera (3216 in total) were identified to Family level, with a total of 97 morphospecies, belonging to 19 Families. Insects from Diptera, Lepidoptera and Orthoptera were not identified further due to their low numbers. The abundance and diversity of insects were affected by seasons, sites and tree species. The number of insects was high during the spring season with 1782 insects, and summer coming second with 1104 individuals, followed by autumn (238 insects), then winter (92). B. discolor sampled for a great number of insects (1741) as compared to S. birrea (1475). The woodland bushveld (1924 insects) surpassed the savannah grassland (1292 insects) site in terms of the insect numbers sampled. / NRF