How Bees Respond Differently to Field Margins of Shrubby and Herbaceous Plants in Intensive Agricultural Crops of the Mediterranean Area

(1) Intensive agriculture has a high impact on pollinating insects, and conservation strategies targeting agricultural landscapes may greatly contribute to their maintenance. The aim of this work was to quantify the effect that the vegetation of crop margins, with either herbaceous or shrubby plants, had on the abundance and diversity of bees in comparison to non-restored margins. (2) The work was carried out in an area of intensive agriculture in southern Spain. Bees were monitored visually and using pan traps, and floral resources were quantified in crop margins for two years. (3) An increase in the abundance and diversity of wild bees in restored margins was registered, compared to non-restored margins. Significant differences in the structure of bee communities were found between shrubby and herbaceous margins. Apis mellifera and mining bees were found to be more polylectic than wild Apidae and Megachilidae. The abundance of A. mellifera and mining bees was correlated to the total floral resources, in particular, to those offered by the Boraginaceae and Brassicaceae; wild Apidae and Megachilidae were associated with the Lamiaceae. (4) This work emphasises the importance of floral diversity and shrubby plants for the maintenance of rich bee communities in Mediterranean agricultural landscapes

The ecology of crop pollination and its integration into farm management to ensure sustainable and stable crop yields

Bestäubung ist eine zentrale Ökosystemdienstleistung in der Landwirtschaft und daher ist es von großer Bedeutung Bestäuber zu schützen. Während die landwirtschaftliche Produktion von Bestäubern profitiert, können sich ihre Praktiken negativ auf lokaler und landschaftlicher Ebene auf diese auswirken. In dieser Arbeit zeige ich, dass gleichzeitig-blühende Kulturen die Zusammensetzung von Bestäubergemeinschaften verändern können. Honigbienen werden aus Apfelplantagen zu Rapsfeldern gelockt. Wildbienen hingegen bleiben in den Apfelanlagen. Landwirte können Wildbienen durch Nistmaterial fördern, welche synergetisch mit Honigbienen den Fruchtansatz erhöhen. Viele Insekten können als Bestäuber gemanagt werden, aber Risiken sollten berücksichtigt werden. Um Bestäubung in die Betriebsführung zu integrieren, benötigt es aber die Bereitschaft der Landwirte. Ich zeige, dass die Entscheidungsfindung von Landwirten von externen Faktoren, sowie ihrer Wahrnehmung von Bestäubern beeinflusst wird.Pollination is a key ecosystem service in agricultural systems. Therefore, it is of major importance to conserve insect pollinators to sustain productivity. While agriculture is benefiting from the services pollinators provide, its practices on local and landscape scale are affecting pollinator abundances and foraging decision. In this thesis, I show that co-blooming crops can alter the pollinator composition as honey bees are drawn away from apple orchards to oilseed rape fields. Wild bee populations remain stable, possibly ensuring pollination. Wild bees can be promoted by installing nesting material, but enhance fruit set only synergistically with honey bees. I can show that many insect species can be managed, but risks should be considered. Finally, integrating pollination into farm management needs the willingness of farmers. I can show that farmers decision-making is affected by external factors and their perception of pollinators, which mainly influenced by on-farm experiences

A global-scale expert assessment of drivers and risks associated with pollinator decline.

Pollinator decline has attracted global attention and substantial efforts are underway to respond through national pollinator strategies and action plans. These policy responses require clarity on what is driving pollinator decline and what risks it generates for society in different parts of the world. Using a formal expert elicitation process, we evaluated the relative regional and global importance of eight drivers of pollinator decline and ten consequent risks to human well-being. Our results indicate that global policy responses should focus on reducing pressure from changes in land cover and configuration, land management and pesticides, as these were considered very important drivers in most regions. We quantify how the importance of drivers and risks from pollinator decline, differ among regions. For example, losing access to managed pollinators was considered a serious risk only for people in North America, whereas yield instability in pollinator-dependent crops was classed as a serious or high risk in four regions but only a moderate risk in Europe and North America. Overall, perceived risks were substantially higher in the Global South. Despite extensive research on pollinator decline, our analysis reveals considerable scientific uncertainty about what this means for human society.University of Reading’s Building Outstanding Impact Support Programm

APICULTURE ADAPTATIONS IN A SHIFTING WORLD: THE BEEKEEPER’S EXPERIENCE ACROSS THE GLOBE

Existing research suggests that changes in climate, such as rainfall and temperature shifts, will threaten bees’ main food sources and cause detrimental impacts on apiculture globally. Despite this, to the best of the author’s knowledge, there is little available by way of research relating to how beekeepers themselves experience these increased pressures to their practices. This research project investigated the experiences of beekeepers in the United States, Malawi, and Cameroon. Surveys of US beekeepers, and interviews with Malawian and Cameroonian beekeepers were coded for emergent themes and surveys were analyzed via descriptive statistics. Major differences in challenges reported by beekeepers in the United States and Sub-Saharan Africa included a higher incidence of disease and pest prevalence in the US, and more issues surrounding resource and materials access in Malawi and Cameroon. Survey and interview observations on temperature and precipitation contained common emergent themes such as climate “unpredictability” and “extreme” weather events paired with adaptations including supplementary feeding, hive construction and placement alterations, temporal shifts in practices, and increased monitoring techniques. As pollinators such as honey bees are essential to food systems and biodiversity across the globe, all practices to promote the health of managed bee populations are to be encouraged. Beekeeping adaptation may be vital to ensuring continued pollination services, for which demands are expected to increase in the future landscape of agriculture. For these reasons the global community would benefit from more cross-cultural exchange of methods to practice beekeeping sustainably, and in-depth research into the adaptation themes uncovered in this study

Socioecological Factors and Farmer Perceptions Impacting Pesticide Use and Pollinator Conservation on Cucurbit Farms

While research suggests that pollinator decline is linked with agricultural practices, it is unclear whether farmers share this view and adapt management to promote pollinators based on their understanding of these threats. To address these issues, we surveyed farmers of pollinator-dependent cucurbit crops across four states in the Midwest, USA. We grouped farmers by their perceptions of pollinator declines and routes of pesticide exposure and used statistical models to evaluate if farmers manage pests and pollinators based on these perceptions. Out of 93 completed surveys, 39% of farmers believed pollinators were in decline. When grouped, 17% of farmers were classified as proponents, ranking (on a 1–5 Likert scale) the factors mediating pesticide exposure and pollinator declines as important or highly important. For comparison, 44 and 39% of farmers were classified as neutral or skeptical, respectively, of these same factors. Compared to the neutral and skeptic groups, proponents were on average younger, had fewer years farming but more years in family farming, and were more dependent on income from outside the farming system. Proponents also on average reported smaller farms, higher pest richness, more land in cucurbit production, and greater richness of crops that are not pollinator dependent, when compared to the neutrals and skeptics. We did not find pest and pollinator management to be related to farmer perceptions of pollinator decline or routes of pesticide exposure, but farmers classified as pollinator “proponents” were more likely to indicate participation in future pollinator habitat restoration programs. Rather, management strategies were better explained by on-farm environmental conditions (e.g., pest richness, farm size, number of pollinator dependent crops) and economic factors (e.g., sources of income). Generally, our research shows that farmers who perceive pollinator threats may not be using pollinator supportive practices. Thus, while some farmers believe in pollinator declines, there remains a need to connect this knowledge with on-farm practices

Honeybees are far too insufficient to supply optimum pollination services in agricultural systems worldwide

Evidence of a decline in wild pollinators is increasing across global and local habitats. However, with regional variation, the number of managed pollinators has increased globally. Whether these managed pollinators can sufficiently meet the agricultural pollination demand given wild pollinator declines remains unclear. Data on 49 honeybee-pollinated crops cultivated worldwide and stocked honeybee colonies were analysed to assess the pollination demand and pollination service capacity between 1989 and 2019. We found a rapidly increasing demand for honeybee pollination but a decreasing pollination service capacity of honeybee colonies. Globally, the demand for honeybee pollination rose approximately 2.3 times higher than the stocked number of honeybee colonies in 2019, growing 1.78% annually, almost 2 times faster than honeybee colonies (0.95%). On average, the pollination service capacity, growth rates of demands for honeybee colony stocks and honeybee pollination, and diversity of honeybee-pollinated crops varied regionally. Nevertheless, fluctuation of the honeybee-pollination demand increased with increased fluctuation of crop diversification. Oil crops accounted for over 70% of the world's honeybee-pollination demand in 2019, with soybean and rapeseed accounting for 39% and 16%, respectively. This was the case in less diversified countries, where a few crops dominated the demand for honeybee pollination, including American countries such as Argentina, Brazil, and the USA, compared to more diversified countries such as China, India, and Japan in Asia. Our study shows that managed pollinators are far too insufficient to adequately supply the agricultural pollination demand worldwide. This emphasises the importance of ongoing calls for protecting pollinators and the integrated management of honeybees and wild pollinator assemblages for a sustainable food-secure future world.Fil: Mashilingi, Shibonage K.. Chinese Academy of Sciences; República de ChinaFil: Zhang, Hong. Chinese Academy of Sciences; República de ChinaFil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Sede Andina. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; ArgentinaFil: An, Jiandong. Chinese Academy of Sciences; República de Chin

The ecomics of ecosystems and biodiversity: scoping the scale

The G8 decided in March 2007 to initiate a “Review on the economics of biodiversity loss”, in the so called Potsdam Initiative: 'In a global study we will initiate the process of analysing the global economic benefit of biological diversity, the costs of the loss of biodiversity and the failure to take protective measures versus the costs of effective conservation. The study is being supported by the European Commission (together with the European Environmental Agency and in cooperation with the German Government. “The objective of the current study is to provide a coherent overview of existing scientific knowledge upon which to base the economics of the Review, and to propose a coherent global programme of scientific work, both for Phase 2 (consolidation) and to enable more robust future iterations of the Review beyond 2010.

Managed honeybees and South American bumblebees exhibit complementary foraging patterns in highbush blueberry

Despite Apis mellifera being the most widely managed pollinator to enhance crop production, they are not the most suitable species for highbush blueberries, which possess restrictive floral morphology and require buzz-pollination. Thus, the South American bumblebee Bombus pauloensis is increasingly managed as an alternative species in this crop alongside honeybees. Herein, we evaluated the foraging patterns of the two species, concerning the potential pollen transfer between two blueberry co-blooming cultivars grown under open high tunnels during two seasons considering different colony densities. Both managed pollinators showed different foraging patterns, influenced by the cultivar identity which varied in their floral morphology and nectar production. Our results demonstrate that both species are efficient foragers on highbush blueberry and further suggest that they contribute positively to its pollination in complementary ways: while bumblebees were more effective at the individual level (visited more flowers and carried more pollen), the greater densities of honeybee foragers overcame the difficulties imposed by the flower morphology, irrespective of the stocking rate. This study supports the addition of managed native bumblebees alongside honeybees to enhance pollination services and emphasizes the importance of examining behavioural aspects to optimize management practices in pollinator-dependent crops.Instituto de Ingeniería RuralFil: Estravis-Barcala, María Cecilia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Estravis-Barcala, María Cecilia. CONICET-Universidad de Buenos Aires. Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE); ArgentinaFil: Macri, Ivana. CONICET-Universidad de Buenos. Instituto de Fisiología, Biología Molecular y Neurociencias; ArgentinaFil: Macri, Ivana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Ingeniería Rural; ArgentinaFil: Nery, Denise. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Nery, Denise. CONICET-Universidad de Buenos Aires. Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE); ArgentinaFil: Farina, Walter M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Farina, Walter M. CONICET-Universidad de Buenos Aires. Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE); ArgentinaFil: Palottini, Florencia. CONICET-Universidad de Buenos Aires. Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE); ArgentinaFil: Palottini, Florencia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin

Desafios para o uso sustentável da polinização na agricultura : ameaças da intensificação agrícola nos benefícios socioeconômicos da polinização

Tese (doutorado)—Universidade de Brasília, Centro de Desenvolvimento Sustentável, Programa de Pós-Graduação em Desenvolvimento Sustentável, 2019.Alimentar a crescente população global sem comprometer o funcionamento dos ecossistemas e a biodiversidade é um dos grandes desafios da agricultura. A polinização agrícola é um serviço ecossistêmico importante para a produção de alimentos e que está ameaçado pelo próprio sistema produtivo agrícola. Partindo dos conhecimentos das ciências da natureza, este pesquisa explora essa problemática pela perspectiva socioeconômica e em diferentes níveis de análise focando no benefício econômico desse serviço, nos custos associados ao seu manejo e nas estratégias de proteção aos polinizadores. O questionamento central desta tese é compreender, em diversos níveis, quais são os benefícios socioeconômicos associados aos serviços de polinização agrícola? O tema foi abordado em três níveis espaciais de análise: local, da paisagem e nacional/global. O estudo no nível local avaliou como o manejo agrícola convencional afeta os benefícios econômicos que os produtores recebem dos polinizadores. Para isso, utilizou-se de um modelo baseado na função de produção que foi aplicado na polinização do feijão comum (Phaseolus vulgaris L.), produzido em fazendas do Distrito Federal e Goiás, Brasil. Os resultados demonstram que a aplicação de práticas que aumenta a abundância de polinizadores nativos juntamente com o uso eficiente de fertilizantes é mais rentável ao produtor do que a intensificação agrícola convencional. Em seguida, o estudo no nível da paisagem avaliou como a atual política brasileira de conservação da natureza pode beneficiar economicamente o produtor por meio dos serviços de polinização. O estudo focou em sistemas agrícolas de feijão localizados em regiões regidas pelo Código Florestal Brasileiro. Os resultados mostram que, os polinizadores nativos associados à potenciais áreas de Reserva Legal beneficiam economicamente os produtores mesmo na ausência de instrumentos econômicos que estimulam a conservação da natureza. Por fim, o estudo avaliou como o comércio internacional de produtos agrícolas dependentes de polinizadores está expandindo a área agrícola pelo mundo (nível nacional/global). Usando dados de 52 culturas para 115 países durante 1993 e 2015, os resultados mostram que, para atender o seu consumo interno, os países mais desenvolvidos demandam intensamente os serviços de polinização (i.e., fluxo virtual de polinização) dos países menos desenvolvidos. Consequentemente, esse comércio é um dos principais causadores da expansão das áreas agrícolas nos países exportadores. Com base em todos os resultados deste estudo, pode-se concluir que para a proteção dos polinizadores é necessária uma ação coordenada entre diferentes tomadores de decisões que atuam em diversos níveis.Fundação de Apoio à Pesquisa do Distrito Federal (FAP/DF); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).To feed a growing global population with no depletion in ecosystem and biodiversity is a great challenge for agriculture. Crop pollination is an important ecosystem service for food production that is under threat due to crop systems. This thesis aims to explore such issue using a socioeconomic perspective and a multi-level approach focusing on economic benefit of this service, on its associated cost of management, and on strategies to protect pollinators. The main question of this thesis is to understand what are the socioeconomic benefits associated to crop pollination services at different levels of analysis? The approach was based on three spatial levels of analyze: local, landscape, and national/global. The study at local level assessed how conventional management affects the economic benefits that farmers receive from pollinators. A production function based model was applied on pollination of common bean production (Phaseolus vulgaris L.) located at central Brazil. Results showed that the application of practices that increase the abundance of native pollinators in addition to efficient use of fertilizer is more profitable to farmers than conventional agricultural intensification. Secondly, the study at landscape level assessed how current Brazilian nature conservation policies affect farmers‟ profitability via pollination services. The focus was on crop system of common bean ruled by Brazilian Forest Code. Results showed that native pollinators associated to potential areas of Legal Reserve bring economic output for farmers even in the absence of economic instruments to stimulate nature conservation. Lastly, the study assessed how international trade of pollinator-dependent crops is expanding cropland areas worldwide (national/ global level). Using data on 52 crops in 115 countries over 1993-2015, the results showed that, to meet domestic consumption, most developed countries intensively demand pollination services (i.e., virtual flow of pollination) from less developed countries. Consequently, this trade is one of the main drivers of cropland expansion in exporting countries. Taking into account those results, I conclude that to protect pollinators is required coordinated actions between stakeholders that act in several spatial levels