How well do we understand landscape effects on pollinators and pollination services?

Abstract

Many studies in the past decade, mostly in temperate countries, have documented the effects of habitat loss and fragmentation on species richness, composition, and abundance and the behaviour of pollinators. Changes in landscape structure are considered to be the primary causes of the limitation of pollination services in agricultural systems. Here, we review evidence of general patterns as well as gaps in knowledge that could be used to support the development of policies for pollinator conservation and the restoration of degraded landscapes. Our results indicate a recent increase in the number of studies on the relationships between pollination processes and landscape patterns, with some key trends already being established. Many authors indicate, for example, that the spatial organization of a landscape has a great influence on the survival and dispersal capacity of many pollinators, as spatial organization affects resource availability and determines the functional connectivity of the landscape. Additionally, the shape, size and spatial arrangement of the patches of each type of natural environment, as well as the occurrence of different types of land use, can create sites with different degrees of connectivity or even barriers to movement between patches, which can deeply modify pollinator flows through the landscape and consequently the success of cross-pollination. However, there are still some gaps, such as in the knowledge of which critical values of habitat loss can lead to drastic increases in pollinator extinction rates, information that is needed to evaluate at what point plant-pollinator interactions may collapse. We also need to concentrate research effort on improving a landscape’s capacity to facilitate pollinator flow (connectivity) between crops and nesting/foraging areas.

Supporting Bees in Cities: How Bees Are Influenced by Local and Landscape Features

“…Of the two, local features are presumed to influence insect diversity the most [45,46]. Regardless, the improvement of surrounding landscapes in conjunction with local features can better enhance pollinator diversity [47,48]. The constituents relating to both landscape and local features will be discussed in further detail below in which knowledge gaps within each area will be addressed.…”

Are Reproductive Traits Related to Pollen Limitation in Plants? A Case Study from a Central European Meadow

“…A partial cause of low pollen limitation in our study could be that the targeted semi-natural locality is situated in a relatively well-preserved and mosaic-like landscape with a limited influence of intensive agriculture. Such semi-natural, diverse, and heterogeneous environments support pollination services [28,29] and thus increase the plant reproductive success, as suggested by Bennett et al [13] in their Romanian meadow community. (4) Effect of plant community composition and study species selection.…”

Agroecological Strategies to Safeguard Insect Pollinators in Biodiversity Hotspots: Chile as a Case Study

“…Pollination services delivered by native insects have been shown to rely strongly on their proximity to natural habitats [109,248,249]. Protected natural areas host higher biodiversity [250] but are not enough to sustain ecological stability [251]. To achieve stability, habitats that have been altered by human activities, including urban zones and areas utilized for productive activities, need to be restored as much as possible [252], leading to effective conservation outcomes by assessing their coverage (i.e., the number and types of species included within their limits) and management [253].…”