Ecological intensification to mitigate impacts of conventional intensive land use on pollinators and pollination

Abstract

Worldwide, human appropriation of ecosystems is disrupting plant-pollinator communities and pollination function through habitat conversion and landscape homogenisation. Conversion to agriculture is destroying and degrading semi-natural ecosystems while conventional land-use intensification (e.g. industrial management of large-scale monocultures with high chemical inputs) homogenises landscape structure and quality. Together, these anthropogenic processes reduce the connectivity of populations and erode floral and nesting resources to undermine pollinator abundance and diversity, and ultimately pollination services. Ecological intensification of agriculture represents a strategic alternative to ameliorate these drivers of pollinator decline while supporting sustainable food production, by promoting biodiversity beneficial to agricultural production through management practices such as intercropping, crop rotations, farm-level diversification and reduced agrochemical use. We critically evaluate its potential to address and reverse the land use and management trends currently degrading pollinator communities and potentially causing widespread pollination deficits. We find that many of the practices that constitute ecological intensification can contribute to mitigating the drivers of pollinator decline. Our findings support ecological intensification as a solution to pollinator declines, and we discuss ways to promote it in agricultural policy and practice.

5 Key Challenges and Solutions for Governing Complex Adaptive (Food) Systems

“…Often characterized by homogenous landscapes with little to no habitat or refuge for biodiversity, modern intensive agricultural systems themselves currently entail at least one cause of pollinator declines due to a lack of floral and nesting resources [82][83][84][85]. In addition to vegetated sites for refuge, pollinator health is dependent on the availability of a diverse range of plants (and their pollen) with non-overlapping flowering periods typically found in (semi-) natural habitats, as the flowering period of a single plant species found within managed crops systems is often shorter than the activity period of pollinators [86].…”

Fragmentation of nest and foraging habitat affects time budgets of solitary bees, their fitness and pollination services, depending on traits: Results from an individual-based model

“…Agricultural intensification limits solitary bees to live on resource islands in an unrewarding matrix [9, 10], because dominant crops provide hardly any foraging resources (e.g. wheat, maize, rice) and separate nest from foraging habitat [11], thereby creating a mosaic of fields and natural elements.…”

Intersection between biodiversity conservation, agroecology, and ecosystem services

“…While many studies have documented increases in pollinator abundance and richness with local wildflower and hedgerow plantings (as discussed in above), monitoring for increases in pollination services and impact on crop yield within crop fields has been less frequent (Kovacs-Hostyanszki et al 2017). Nevertheless, with a cost-benefit analysis, Morandin, Long, and Kremen (2016) demonstrated that increased pollination (and pest control) services render hedgerows economically viable for growers.…”

“…The relationship between soil management and pollination and pest control services can be ambiguous and is not well studied. While tilling negatively impacts pollinator abundance and diversity (discussed above), no studies directly document impacts of tilling on pollination services (Kovacs-Hostyanszki et al 2017). Similarly, even though reduced till benefits numerous natural enemies, the effect cannot be generalized.…”