Redes de interações entre polinizadores e culturas agrícolas em diferentes escalas espaciais

Abstract

Pollination is a crucial ecosystem service for food production. One of the goals of the ONU 2030 agenda is to eradicate hunger, ensure food security, improve nutrition and promote sustainable agriculture. To achieve this, it is necessary to implement resilient agricultural practices that preserve ecosystems and conserve pollinators, which are essential for main food crops. Through network science, this thesis' main objective is to understand the structure of interactions between plants and pollinators at different spatial scales (global and local) and to investigate the main interactions that can favor the pollination of crops of food and economic importance. The thesis is structured into three chapters. In Chapter I, we seek to understand the pattern of interactions between pollinators and cultivated Malvaceae species (cotton, cocoa, cupuaçu and okra) on a global scale through a meta-network of interactions. We identified that the meta-network of Malvaceae-pollinator interactions has four modules, each module formed by a crop and a few shared pollinators. Apis mellifera was the only connecting species in the network. In this chapter we can conclude that each crop is pollinated by a very specific group of species, indicating that the maintenance of productivity can be favored by the conservation of the diversity of pollinators. In Chapter II, we investigated, through a literature review, the pollination of cocoa, describing the spatial and temporal distribution of studies, verifying the global distribution of pollinators (through a spatial network) and identifying the key pollinators for their production. 29 articles were included in the analyses. The years of publications found ranged from 1950 to 2024. The countries that had the highest number of studies were Ghana (21%) and Indonesia (17%). The network recorded a total of 39 links between 14 countries and 13 pollinators (nine flies, three ants and one bee). Flies of the genus Forcipomyia have been classified as key pollinators of cocoa flowers. In Chapter III, we aimed to identify the interactions between co-flowering cultivated plants (pumpkin, watermelon, melon, gherkin, tomato and pepper) and bees in a family farming area in the semi-arid region of Brazil and classify the functional roles of the species in the network. The network presented a modular structure, formed by four modules, apparently guided by floral attributes. No species of bee was classified as a hub of the network. Paratrigona incerta and Ceratina sp. were classified as module hubs. Paratrigona incerta showed the greatest number of interactions with crops, interacting with all crops, except pumpkin. Apis mellifera, was the second species with the highest number of interactions, being linked to all Cucurbitaceae. We realized, therefore, that the networks of interactions between pollinators and cultivated plants presented a modular structure regardless of the spatial scale (global or local) and that the composition of the modules may be related to floral attributes such as size and resources offered. Native bees have great potential for pollination in agricultural areas. Pollination networks can constitute an important criterion in making decisions about pollinator management and conservation, as they identify key pollinators.