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Invasive species can reach high abundances and dominate native environments. One of the most impressive examples of ecological invasions is the spread of the African subspecies of the honey bee throughout the Americas, starting from its introduction in a single locality in Brazil. The invasive honey bee is expected to more negatively impact bee community abundance and diversity than native dominant species, but this has not been tested previously. We developed a comprehensive and systematic bee sampling scheme, using a protocol deploying 11,520 pan traps across regions and crops for three years in Brazil. We found that invasive honey bees are now the single most dominant bee species. Such dominance has not only negative consequences for abundance and species richness of native bees but also for overall bee abundance (i.e., strong “numerical” effects of honey bees). Contrary to expectations, honey bees did not have stronger negative impacts than other native bees achieving similar levels of dominance (i.e., lack of negative “identity” effects of honey bees). These effects were markedly consistent across crop species, seasons and years, and were independent from land-use effects. Dominance could be a proxy of bee community degradation and more generally of the severity of ecological invasions.

The use of robust sample methodologies to estimate the highest number of species with different ecological requirements and traits is essential to the knowledge construction of the biodiversity and to establish wildlife assessment and monitoring programs. Our aims were to study the performance of colored pan traps in the capture of Drosophilidae (Diptera), a method never used for sampling this taxon. During six months, colored pan traps (blue, yellow and white) were tested in three areas in Southern Brazil. We captured 375 individuals of 30 species belonging to four genera of Drosophilidae. The most abundant species were Drosophila lutzii (n=215) p=0.58, Scaptomyza sp. (n=55) p=0.15 and D. bromelioides (n=17) p=0.04, all of them, anthophilous species. All colored pan traps captured a high quantify species of Drosophilidae, mainly anthophilous species.

2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme, and with the funding organisations AEI, NWO, ECCyT and NSF Funding information, Allen-Perkins A, Magrach A, Dainese M, Garibaldi LA, Kleijn D, Rader R, Reilly JR, Winfree R, Lundin O, McGrady CM, Brittain C, Biddinger DJ, Artz DR, Elle E, Hoffman G, Ellis JD, Daniels J, Gibbs J, Campbell JW, Brokaw J, Wilson JK, Mason K, Ward KL, Gundersen KB, Bobiwash K, Gut L, Rowe LM, Boyle NK, Williams NM, Joshi NK, Rothwell N, Gillespie RL, Isaacs R, Fleischer SJ, Peterson SS, Rao S, Pitts-Singer TL, Fijen T, Boreux V, Rundlöf M, Viana BF, Klein AM, Smith HG, Bommarco R, Carvalheiro LG, Ricketts TH, Ghazoul J, Krishnan S, Benjamin FE, Loureiro J, Castro S, Raine NE, de Groot GA, Horgan FG, Hipólito J, Smagghe G, Meeus I, Eeraerts M, Potts SG, Kremen C, García D, Miñarro M, Crowder DW, Pisanty G, Mandelik Y, Vereecken NJ, Leclercq N, Weekers T, Lindstrom SAM, Stanley DA, Zaragoza-Trello C, Nicholson CC, Scheper J, Rad C, Marks EAN, Mota L, Danforth B, Park M, Bezerra ADM, Freitas BM, Mallinger RE, Oliveira da Silva F, Willcox B, Ramos DL, D da Silva E Silva F, Lázaro A, Alomar D, González-Estévez MA, Taki H, Cariveau DP, Garratt MPD, Nabaes Jodar DN, Stewart RIA, Ariza D, Pisman M, Lichtenberg EM, Schüepp C, Herzog F, Entling MH, Dupont YL, Michener CD, Daily GC, Ehrlich PR, Burns KLW, Vilà M, Robson A, Howlett B, Blechschmidt L, Jauker F, Schwarzbach F, Nesper M, Diekötter T, Wolters V, Castro H, Gaspar H, Nault BA, Badenhausser I, Petersen JD, Tscharntke T, Bretagnolle V, Willis Chan DS, Chacoff N, Andersson GKS, Jha S, Colville JF, Veldtman R, Coutinho J, Bianchi FJJA, Sutter L, Albrecht M, Jeanneret P, Zou Y, Averill AL, Saez A, Sciligo AR, Vergara CH, Bloom EH, Oeller E, Badano EI, Loeb GM, Grab H, Ekroos J, Gagic V, Cunningham SA, Åström J, Cavigliasso P, Trillo A, Classen A, Mauchline AL, Montero-Castaño A, Wilby A, Woodcock BA, Sidhu CS, Steffan-Dewenter I, Vogiatzakis IN, Herrera JM, Otieno M, Gikungu MW, Cusser SJ, Nauss T, Nilsson L, Knapp J, Ortega-Marcos JJ, González JA, Osborne JL, Blanche R, Shaw RF, Hevia V, Stout J, Arthur AD, Blochtein B, Szentgyorgyi H, Li J, Mayfield MM, Woyciechowski M, Nunes-Silva P, Halinski de Oliveira R, Henry S, Simmons BI, Dalsgaard B, Hansen K, Sritongchuay T, O'Reilly AD, Chamorro García FJ, Nates Parra G, Magalhães Pigozo C, Bartomeus I

Social bees rely on food resources collected from flowers while foraging to guarantee the survival of their offspring. Pollen and nectar are the most important of these resources for protein and energy sources. This study analyzed the maximum flight distance of Tetragonisca fiebrigi (Shwarz, 1938) and the influence of sugar concentration of food resources and abiotic factors on visiting rates. Experiments were carried out in the Botanical Garden in South Brazil. The workers were training to collect sugar syrup from artificial feeders (water and sugar, 1:1) to which an aromatic essence (peach) had been added to attract the bees. It was found that workers reduced the number of visits as the distance to food sources increased. The experiments with feeders indicated that the maximum flight distance of T. fiebrigi workers from the four colonies analyzed reached 600 m. Additionally, 95% of visits to the feeder were within 350 m (colony C) or 400 m (colonies A, B, and D) of the hives. The number of worker visits could be significantly explained for all colonies (p

Insect pollination is essential for the maintenance of ecosystems and for agricultural productivity. Bees are the main pollinator group and their assemblages are threatened by agricultural intensification. This study aimed to compare the diversity and structuring of bee assemblages between organic and conventional agroecosystems and to evaluate the influence of landscape composition on bee abundance in the Pampa biome. The study was carried out on three organic and three conventional family farms. Sampling was performed during the summer using pan traps. Four sampling units were placed on each farm, of which three were placed in crop field areas and one in native forest remnants. The diversity profile showed no significant difference between agroecosystems. Species abundance distribution indicates fewer dominant species in the organic system, suggesting the positive influence of polyculture on assemblage structure. Bee composition was different between agroecosystems. Notably, the species composition of bees in the forest edge of conventional farms was quite similar to that found in the organic habitats, indicating the importance of forested environments as a refuge for bees in conventional systems. The landscape analysis showed that the increase in the proportion of crop field areas negatively influenced the abundance of bees. We suggest that the maintenance of a heterogeneous agricultural landscape and smallholdings, composed of native and semi-natural habitats and organic practices on family farms can help to provide diverse niches for wild bees in the Pampa, contributing to biodiversity conservation and supporting ecosystem processes, like pollination.

Fil: Halinski, Rosana. Pontifícia Universidade Católica do Rio Grande do Sul. Escola Politécnica; Brasil. Fil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: dos Santos, Charles F. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Acosta, André L. Universidade de São Paulo. Laboratório de Ecologia de Paisagens e Conservação. Instituto de Biociências. Departamento de Ecologia; Brasil. Fil: Dornelles Guidi, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Blochtein, Betina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Ecosystem services are fundamental to the maintenance of biodiversity, food security, livestock and biofuel production. Here, we analyze the impact of the distance between forest fragments and oilseed crops (Brassica napus) on the crops' yield (kg/ha) and economic value (US$). For crop yield, the total loss field−1 was calculated as the difference between the most lucrative parcel and the least lucrative parcel. Hypothetical models were developed to estimate the potential changes in crop incomes due to progressive replacement of the lowest income crop area(s) by natural vegetation. Our findings demonstrate a significant decrease in the mean number of seeds per silique and in seed production as the distance from forest fragment progressively increases. The productivity loss throughout this gradient may reach up to 2760 kg/ha (i.e. US$804.08). Our models indicate that parcels further than 325 m from forest fragments were poorly pollinated. Our models also demonstrated that farmers could boost their yields if more natural areas (as small as 5%) were included inside crop fields, even though this reduces their arable area. In conclusion, adding small natural patches within crop fields will most likely lead to a higher seed production and successive increases in the economic value of canola crops.

Most cultivars of apple trees are highly dependent on insects for successful pollination and fruit production. In this study, we evaluated the insect diversity in apple orchards of southern Brazil and verified whether or not there is a relationship between the diversity of insect visitors and the characteristics (weight, seed number, and symmetry) of the fruits of ‘Fuji’ and ‘Gala’ apples produced by the orchards. We also evaluated the diversity of insects on flowering weeds within apple orchards and compared it with the apple flowers. Diversity of anthophilous insects was low, in general, and differed between the regions. Furthermore, regarding insect diversity, orchards were grouped by management system: organic orchards were more similar to each other than to conventional orchards. The insect diversity of weed flowers was higher than apple flowers, but insect abundance was greater on apple flowers, suggesting that weeds may increase insect diversity within apple orchards and may sustain pollinators. We found a positive effect of insect diversity on the number of seeds of ‘Fuji’ apples and of honeybee abundance on their weight, suggesting that honeybee management is important in the studied areas. In contrast, we found no significant effect of insect diversity and abundance on ‘Gala’ apple characteristics. Despite this, the analyses of the seeds of ‘Gala’ apples indicate that the orchards may suffer a pollination deficit, which could be overcome by improving insect pollination. These results reinforce previous findings that insect diversity is important for apple yield, but its influence varies with cultivar.

The main sources of food for stingless bees are the nectar and pollen harvested from flowers, whereas one important kind of nesting material (i.e. wax) is produced by their own abdominal glands. Stingless bees can, nonetheless, obtain alternative resources of food and wax from exudates released by sap-sucking insects as honeydew and waxy cover, respectively. To date, there are no comprehensive studies investigating how diversified and structured the network interactions between stingless bees and sap-sucking insects are. Here, we conducted a survey of the data on relationship between stingless bees and sap-sucking insects to evaluate: (1) which resources are collected by which stingless bee species; (2) how diverse the interaction network is, using species degree and specialisation index as a proxy; and if (3) there would be any phylogenetic signal in the species degree and specialisation indices. Our findings demonstrate that approximately 21 stingless bee species like Trigona spp. and Oxytrigona spp. have been observed interacting with 11 sap-sucking species, among which Aethalion reticulatum is the main partner. From ca. 50 records, Brazil is the country with most observations (n = 38) of this type of ecological interaction. We found also that stingless bees harvest fivefold more honeydew than waxy covers on sap-sucking insects. However, we did not find any phylogenetic signal for the occurrence of this interaction, considering species degree and specialisation indices, suggesting that both traits apparently evolved independently among stingless bee species. We suggest that specific ecological demands may drive this opportunistic behaviour exhibited by stingless bees, because major sources of food are obtained from flowers and these bees produce their own wax.

Assessments in agricultural crops indicate that alterations in the landscape adjacent to the crops can result in reduced productivity due to loss or low abundance of pollinating agents. In the canola crop, production is partially dependent on insect pollination. Therefore, knowledge of the faunal diversity within and near crop fields is key for the management of these insects and consequently for the increase in productivity. This study aimed to determine and compare the diversity of bees in habitats associated with canola fields in southern Brazil. Bees were captured in four agricultural areas using pan traps in three habitat classes: (1) flowering canola crop, (2) forest remnant, and (3) grassland vegetation. The highest abundance of bees was observed in the grassland vegetation (50%) and in the flowering canola field (47%). Eight species common to the three habitat classes were recorded, four of which are represented by native social bees. In addition, a single or a few individuals represented species that were exclusive to a specific habitat class; eight species were collected exclusively in the interior of the canola field, 51 in the grassland vegetation, and six in the forest remnant. The majority of the rare species recorded exhibits subsocial or solitary behaviour and inhabit open places. The composition of bee groups differed between the habitats showing the importance of maintaining habitat mosaics with friendly areas for pollinators, which promote the pollination service for canola flowers. Keywords: Canola, Honeybees, Pollinators, Solitary bees

A perda atual da biodiversidade tem consequ?ncias negativas para o meio ambiente e impacta diversos servi?os ecossist?micos de poliniza??o, dos quais a sociedade humana se beneficia direta ou indiretamente. Entre os principais polinizadores destacam-se as abelhas, vespas, cole?pteros, moscas e borboletas. Sabe-se que as abelhas polinizam mais de 90% de 107 culturas globais e que outros insetos podem contribuir com 25-50% na poliniza??o. Estudos sobre canola (Brassica napus L. variedade ole?fera) apontam que a visita de insetos promove o aumento da produtividade dos gr?os de 12 a 47%. Diante disto, o presente trabalho objetivou conhecer a diversidade de abelhas, vespas e cole?pteros em agroecossistema de canola e identificar potenciais polinizadores da cultura. Al?m disso, foi avaliado como a paisagem e os polinizadores influenciam na produtividade de canola, bem como as ?reas de adequabilidade de habitat para esp?cies polinizadoras frente ?s mudan?as clim?ticas em cen?rios futuros (2050). Os insetos foram coletados com o uso de pan traps em oito lavouras de B. napus (Hyola 420 e Hyola 61) nos munic?pios de Esmeralda, Estrela e Guarani das Miss?es, RS, Brasil. Para desenvolvimento dos mapas de adequabilidade de habitat utilizou-se registros de ocorr?ncias das esp?cies em bases de dados e dos munic?pios com lavouras de canola fornecidos por fomentadoras da cultura. Dentre as vespas destacam-se as esp?cies sociais Brachygastra lecheguana e Protonectarina sylveirae e as esp?cies solit?rias Campsomeris spp., Eucyrtothynnus spp. e Tiphia spp. como potenciais polinizadores. As fam?lias mais representativas de cole?pteros foram Melyridae, Curculionidae, Nitidulidae, Chrysomelidae e Scarabaeidae, sendo que a esp?cie mais abundante, Astylus variegatus, que ? polin?faga, com corpo pubescente e densas cerdas, aos quais os gr?os de p?len se aderem e s?o transportados, portanto, provavelmente ? polinizador da canola e de flores do entorno. A produtividade de canola foi positivamente influenciada pela diversidade de abelhas, sociais e solit?rias, e a dist?ncia do remanescente florestal afetou a composi??o das guildas de abelhas presentes no interior da lavoura. Foi observado que as ?reas seminaturais tiveram correla??o positiva com a riqueza de abelhas sociais nativas. J? na categoria de paisagem denominada ?Mata?, pode-se observar que h? correla??o negativa no raio de 1000 metros com a abund?ncia de abelhas subsociais ou solit?rias, possivelmente atribu?do ao h?bito de nidifica??o destas, que ? predominantemente subterr?neo, isto ?, n?o dependem exclusivamente de florestas para construir seus ninhos. Em conson?ncia, na categoria de ?Agricultura?, a paisagem agr?cola no raio de 1000 metros foi correlacionada positivamente com a abund?ncia da mesma guilda, fato atribu?do a nidifica??o no interior das lavouras. Diante de diferentes graus de heterogeneidade da paisagem nas lavouras de canola pode-se observar que a composi??o de insetos no agroecossistema da canola responde aos fatores ecol?gicos e hist?ricos de cada regi?o, relacionando-se com a qualidade do habitat e recursos alimentares para as esp?cies. As ?reas de adequabilidade de habitat para canola mostram um elevado potencial para expans?o da cultura no futuro, contudo para que isto aconte?a deve-se estabelecer estrat?gias como a utiliza??o de cultivares que tenham maior toler?ncia ?s vari?veis clim?ticas, visto que estas afetam a fenologia das plantas. Em acr?scimo, sugere-se empregar esfor?os para introdu??o da cultura em lugares que s?o adequados no cen?rio futuro. Al?m disso, ao compararmos a adequabilidade de habitat somente para canola e depois em sobreposi??o com as esp?cies de abelhas sem ferr?o, podemos observar que as ?reas adequadas aumentam expressivamente, refor?ando que para expans?o da cultura necessita-se medidas de conserva??o de habitats naturais e seminaturais para fornecer recursos alimentares e de nidifica??o para os polinizadores. The current loss of biodiversity has negative consequences for the environment and impacts several pollination ecossystem services, from which human society benefits directly or indirectly. Among the main pollinators bees, wasps, coleopterans, flies and butterflies stand out. Bees pollinate more than 90% of 107 worldwide crops and other insects might contribute with 20-50% of pollination. Studies about canola (Brassica napus L. cultivar ?ole?fera?) point out that insect visitation promotes an increase of 12 to 47% in grain productivity. Faced with this, the present work aimed to know the bee, wasp and coleopteran diversity in the canola agroecossystem and identify potential pollinators of the crop. Furthermore, it was evaluated how the landscape and the pollinators influence in the productivity of canola, as well as the habitat suitability for the pollinator species in the face of climatic change in future scenarios (2050). Insects were collected with pan traps in eight fields of B. napus (Hyola 420 and Hyola 61) in the towns of Esmeralda, Estrela and Guarani das Miss?es, RS, Brazil. For the development of the habitat suitability maps it was used the occurrence records of species in databases and of the canola fields in the towns informed by the crop promoters. Among the wasps the social species Brachygastra lecheguana and Protonectarina sylveirae and the solitary species Campsomeris spp. stand out as potential pollinators. The most representative families of coleopterans were Melyridae, Curculionidae, Nitidulidae, Chrysomelidae and Scarabaeidae, and the most abundant species, which is is polliniferous, with a pubescent body and dense bristles, to which the pollen grains adhere and are transported, thus probably it is a pollinator of canola and surrounding flowers. The productivity of canola was positively influenced by the diversity of social and solitary bees, and the distance from the forest fragment affected the composition of bee guilds present inside the canola fields. It was observed that the semi-natural areas presented a positive correlation with the social native bee species richness. Regarding the category of landscape named ?Forest?, it was observed that there is a negative correlation in the 1000 meters radius with the subsocial or solitary bee abundance, possibly explained by their nesting habit, which is mainly underground, which means that it is not exclusively dependent of forest to build their nests. Accordingly, in the ?Agriculture? category, the agricultural landscape in the 1000 meters radius was positively correlated to the abundance of the same guild, fact attributed to the nesting inside canola fields. In view of the different degrees of heterogeneity of the landscape in canola crops, it can be observed that the composition of insects in the canola agroecossystem responds to the ecological and historical factors of each region, being related to the quality of the habitat and food resources for the species. The areas of habitat suitability for canola show a high potential for future crop expansion, however, for this to happen, strategies such as the use of cultivars that have greater tolerance to climatic variables should be established, because they affect plant phenology. In addition, it is suggested to use efforts to introduce the crops in places that are suitable in the future scenario. Furthermore, when comparing the habitat suitability only for canola and then in overlapping with the stingless bee species, we can observe that the appropriate areas increase significantly, reinforcing that for the expansion of the crop, conservation measures of natural and semi-natural habitats for providing food and nesting resources for pollinators are needed. Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES

Planning the artificial pollination of agricultural crops requires knowledge of the floral biology and reproductive system of the crop in question. Many studies have shown that rapeseed (Brassica napus Linnaeus) is self-compatible and self-pollinated, but its productivity may be increased by insect visitation. In the present study, the floral biology and the response of productivity to insect visitation of two rapeseed cultivars (Hyola 420 and Hyola 61) were analyzed and compared in three regions of Rio Grande do Sul, Brazil. The rapeseed flowers presented three stages during anthesis, with the time periods varying between the cultivars. Both cultivars are self-compatible, but free visitation of insects increased productivity by 17% in the Hyola 420 cultivar and by approximately 30% in the Hyola 61 cultivar. Therefore, it is concluded that the cultivar Hyola 61 is more dependent on insect pollination than Hyola 420. O planejamento de polinização dirigida nas culturas agrícolas requer o conhecimento da biologia floral e do sistema reprodutivo da cultura em questão. Muitos estudos mostram que a canola (Brassica napus Linnaeus) é auto compatível e auto polinizada, no entanto, sua produtividade pode ser aumentada pela visita por insetos. Nesse estudo, a biologia floral e a resposta da produtividade à visita por insetos de duas cultivares de canola (Hyola 420 e Hyola 61) foram analisadas e comparadas em três regiões do Rio Grande do Sul, Brasil. As flores de canola apresentaram três fases durante a antese, havendo variação no período de tempo de acordo com a cultivar. Ambas as cultivares são auto compatíveis, mas a livre visita por insetos aumentou a produtividade em 17% na cultivar Hyola 420 e cerca de 30% na cultivar Hyola 61. Dessa maneira, concluímos que a cultivar Hyola 61 é mais dependente da polinização entomófila que a Hyola 420.

O servi?o de poliniza??o ? fundamental para a manuten??o da biodiversidade, alimenta??o humana e produ??o de biocombust?veis. Esse servi?o ? amea?ado pela necessidade de aumento da produ??o de gr?os, a qual amplia ?reas de semeadura provocando a degrada??o da vegeta??o e perda da biodiversidade. Assim, em certas culturas a estreita depend?ncia de polinizadores est? relacionada ? qualidade dos habitats adjacentes. Estudos apontam que h? decl?nio de polinizadores conforme aumenta a dist?ncia de remanescentes florestais, promovendo um decr?scimo na produtividade. Brassica napus, popularmente conhecida como canola, se enquadra nesse cen?rio. Dessa maneira, o presente trabalho objetivou caracterizar a assembleia de abelhas em tr?s classes de habitats e analisar o efeito de dist?ncias de remanescentes florestais na produ??o de gr?os e no valor econ?mico de Brassica napus (Hyola 420) no Sul do Brasil. O estudo foi conduzido em quatro ?reas agr?colas com canola, no munic?pio de Esmeralda, RS. A diversidade de abelhas foi amostrada com uso de pan traps em tr?s classes de habitats: (1) lavoura de canola em flora??o; (2) remanescente florestal e (3) vegeta??o campestre. A fim de avaliar a produ??o de gr?os com livre visita??o de insetos a 25 m, 175 m e 325 m da borda de remanescentes florestais foram colhidas nas lavouras de canola 11 a 18 plantas. Para an?lise de produtividade, as plantas foram colhidas em parcelas de 225 m2 e extrapoladas para um hectare. Com os rendimentos projetados calculou-se o preju?zo total/lavoura pela diferen?a entre a parcela mais lucrativa (25 m) e a menos lucrativa (325 m). Foram coletadas 886 abelhas pertencentes a 87 esp?cies. Dentre as fam?lias coletadas, Apidae foi a mais abundante com 441 indiv?duos, sendo 254 da esp?cie Apis mellifera, seguida de Halictidae, Andrenidae, Colletidae e Megachilidae. Nas tr?s classes de habitats amostradas o maior n?mero de indiv?duos foi coletado na vegeta??o campestre (50%) seguido do interior da lavoura de canola em flora??o (47%) e do remanescente florestal (3%). Oito esp?cies foram registradas nas tr?s classes de habitats, sendo quatro destas de abelhas sociais nativas. Al?m disso, foi observado que as esp?cies exclusivas ? determinada classe de habitat foram raras, ou seja, representadas por um ou poucos indiv?duos. Oito esp?cies foram exclusivas do interior da lavoura de canola, 51 da vegeta??o campestre e seis do remanescente florestal. A maioria das esp?cies raras exibe comportamento subsocial ou solit?rio, tamanho reduzido e habita locais abertos. Observou-se um decr?scimo significativo na m?dia de sementes por s?liqua ao longo do gradiente borda-interior em todas as lavouras, exceto na lavoura quatro. Dessa forma, os remanescentes florestais apresentaram um importante papel no rendimento dos gr?os, e, consequentemente no lucro, permitindo inferir que h? perda na produtividade ao longo do gradiente, podendo se alterar em at? 2760 kg/ha, o equivalente a R$ 113.380,80. Nas proje??es realizadas para as quatro lavouras estimou-se que se se a lavoura fosse formada somente parcelas a 325 m do remanescente florestal, o preju?zo teria sido de cerca de R$ 350 mil reais. Considerando-se que a fauna amostrada nos diferentes ambientes agr?colas ? distinta e que a maioria das esp?cies de abelhas se apresenta como potencial agente polinizador para canola sugere-se a manuten??o de habitats campestres e florestais nas proximidades das lavouras de canola. Essa pr?tica pode fornecer subs?dios para a perman?ncia dos polinizadores na ?rea, para que esses efetuem o servi?o de poliniza??o elevando a produ??o de gr?os e o valor econ?mico associado a esse. The pollination service is fundamental to the maintenance of biodiversity, human feeding and production of biofuels. This service is threatened by the need of increasing grain production, which enlarge seeding areas causing the degradation of vegetation and biodiversity loss. Thus, in certain crops the narrow dependence of pollinators is related to the quality of adjacent habitats. Studies point out that there is a decline of pollinators with the increase of the distance to forest fragments, promoting a decrease in productivity. Brassica napus, commonly known as canola, fits this scenario. Therefore, the present work aimed to characterize the assemblage of bees in three classes of habitats and analyze the effect of the distances from forest fragments in the grain production and economic value of Brassica napus (Hyola 420) in southern Brazil. The study was conducted in four agricultural areas with canola, in the town of Esmeralda, RS. The diversity of bees was sampled using pan traps in three classes of habitats: (1) canola field in bloom; (2) forest fragment; and (3) ruderal vegetation. In order to evaluate the production of grains by free visitation of insects at 25 m, 175 m and 325 m from the edge of the forest fragments 11 to 18 plants were harvested in the canola fields. For productivity analysis, the plants were harvested in plots of 225 m2 and extrapolated to one hectare. With the projected incomes it was calculated the total economic loss/field using the difference between the most profitable plot (25 m) and the least profitable one (325 m). It was collected 886 bees belonging to 87 species. Among the families collected, Apidae was the most abundant with 441 individuals, being 254 of the Apis mel?fera species, followed by Halictidae, Andrenidae, Colletidae and Megachilidae. In the three classes of habitats sampled the greatest number of individuals was collected in the ruderal vegetation (50%) followed by the canola field in bloom (47%) and the forest fragment (3%). Eight species were registered in the three classes of habitats, being four of them of native social bees. Besides, it was observed that the species exclusive to determine habitat class were rare, that is, represented by one or few individuals. Eight species were exclusive to the interior of the canola fields, 51 to the ruderal vegetation and six to the forest fragment. Most rare species exibits subsocial or social behavior, small size and inhabit open ?reas. It was observed a significant decrease in the mean number of seeds per silique along the edge-interior gradient in all fields, except in the field four. Thus, the forest fragments presented an importante role in the grain yield, and, consequently in the profit, allowing to infer that there is a loss in the grain productivity along the gradiente, which can be altered in at most 2760 kg/ha, which is equivalent to R$ 113,380.80. In the projections done for the four fields, it was stimated that if the field were formed only by plots of 325 m from the forest fragment, the economic loss would be of around R$ 350 thousand. Considering that the sampled fauna in the different agricultural environments is distinct and that most species of bees are potential pollinators agents of canola, it is suggested the maintenance of ruderal and forest areas nearby canola fields. This practice can provide resources to the permanence of pollinators in the area, so that they can perform the pollination service raising the grain productivity and the economic value associated to this.

The predatory activities of Apiomerus duckei Costa Lima, Seabra & Hathaway, 1951, Apiomerus pilipes (Fabricius, 1787) and Apiomerus luctuosus Costa Lima, Seabra & Hathaway, 1951 (Hemiptera: Reduviidae: Harpactorinae: Apiomerini) on orchid bees (Hymenoptera: Apidae: Apinae: Euglossini) in odoriferous traps in the influence area of Santo Antônio Hydroelectric Power Plant, Rondônia State, Brazil, and of Cosmoclopius annulosus Stål, 1872 (Hemiptera: Reduviidae: Harpactorinae: Harpactorini) on the bee Ceratina rupestris Holmberg, 1884 (Hymenoptera: Apidae: Apinae: Xylocopini: Ceratinina), in an experimental area cultivated with canola in Passo Fundo, Rio Grande do Sul State, Brazil, are recorded by the first time. Resumen. Se registran por primera vez las actividades depredadoras de Apiomerus duckei Costa Lima, Seabra y Hathaway, 1951, Apiomerus pilipes (Fabricius, 1787) y Apiomerus luctuosus Costa Lima, Seabra y Hathaway, 1951 (Hemiptera: Reduviidae: Harpactorinae: Apiomerini) sobre abejas orquídeas (Hymenoptera: Apidae: Apinae: Euglossini) en trampas odoríferas ubicadas en el área de influencia de la Central Hidroeléctrica Santo Antônio (HEP), Estado de Rondônia, Brasil, y de Cosmoclopius annulosus Stål, 1872 (Hemiptera: Reduviidae: Harpactorinae: Harpactorini) sobre la abeja Ceratina rupestris Holmberg, 1884 (Hymenoptera: Apidae: Apinae: Xylocopini: Ceratinina), en un área experimental cultivada con canola en Passo Fundo, Rio Grande do Sul State, Brasil. Made available in DSpace on 2022-10-10T18:09:44Z (GMT). No. of bitstreams: 1 New-records-MarsaloJ.pdf: 693746 bytes, checksum: e632173cd38152b6ddcd96ae69d8af9b (MD5) Previous issue date: 2022