Harnessing nature for more resilient agriculture
Regenerative agriculture is broadly recognised as a means of rebuilding the ecosystems that underpin food production. Healthy ecosystems that support a diversity of species are more effective at recycling nutrients, at providing pollination services, and at regulating pests. In arable systems, focus is typically on actions to improve soil health; cover crops, livestock integration, reduced tillage, incorporating organic matter and reducing synthetic inputs.
The role that soil communities play in food production is undisputable, however, it is important to also recognise the benefits that other natural assets provide. Hedgerows, grassy field margins, riparian buffer strips and floral strips support myriad arthropods that are crucial to food production, including a diversity of natural enemies and pollinating insects.
Approximately 75% of key crops rely on insect pollinators; including pulses, fruits and nuts which are particularly rich in plant-based proteins and micronutrients. Pollinators are, however, struggling, and a recent survey found almost half of European farmers surveyed believed their yields were suffering due to inadequate pollination.
In the UK it has been estimated that a 30% decline in pollinators would result in yield reductions amounting to £188 million per year, highlighting the agronomic importance of insect pollinators. There is, however, a glimmer of hope on the horizon. While more specialist pollinating species continue to decline, the main pollinators of agricultural crops are bucking the trend and actually increasing with agri-environment schemes thought to be a driving factor.
It is important that the UK remains as self-sufficient as possible when it comes to food production, and we therefore need to balance nature-recovery with food production, particularly in areas which support arable production. Finding interventions that work alongside arable farming is crucial; restoring species-rich hedgerows, planting floral-rich strips, establishing riparian buffer strips and growing mass flowering crops (such as field beans and oilseed rape) are all measures that are easily integrated into arable systems. Research has highlighted that due to increased pollination services, implementing such measures had no adverse impact on overall yield, despite taking land out of production.
The creation of such habitats will also benefit a wider range of invertebrates, including key natural enemies which regulate pest populations. Many of these species, including hoverflies and parasitic wasps, require open flower sources (e.g. oxeye daisy, cat’s-ear, and knapweed) to successfully reproduce, and floral strips can increase pest control services in adjacent fields by 16%. In addition to floral resources, natural enemies also need shelter and overwintering site, with hedgerows and undisturbed tussocky grassy field margins providing suitable harbourage for predators such as ground beetles, spiders, and ladybirds.
With several chemical control measures being withdrawn from the market, and pests developing resistance, arable farmers are becoming increasingly reliant on natural enemies. Different natural enemies occupy distinct roles in agricultural ecosystems. Parasitic wasps and hoverfly larvae target aphids in the leaves and heads of cereals, while ground beetles and wolf spiders target pests at ground level where they control slugs and any aphids that drop to the ground to escape canopy active predators. Having a variety of natural enemies results in more effective pest control services and will build resilience to environmental change.
Both insect pollinators and natural enemies require a variety of different resources throughout their lifespan. Parasitic wasps for example, need undisturbed grassy areas to overwinter, they need open flowers to sustain adult populations, and they need a ready supply of aphids to feed their young. Providing a diversity of high-quality, semi-natural habitats across the farm will help to sustain healthy populations of natural enemies and insect pollinators.
Agriculture is currently in a state of flux; climate change, increasing input costs, and the removal of chemicals are among the multitude of pressures faced by arable farmers. Increasing the sustainability and building resilience into arable systems through regenerating ecosystems at the farm scale will help farmers and landowners to tackle these challenges. Here we demonstrate the importance of looking beyond the soil health, and taking a whole-farm approach when it comes to ecological stewardship. Creating and managing high-quality field edges and hedges allows farmers and landowners to harness the power of insects to enhance agricultural productivity and build resilience into their farming system.
If you would like to know more about how we support businesses and land managers to take action in this space, visit sac.co.uk/workingwithyou.
Posted by Lorna Cole on 17/06/2024
