A replicated, controlled, before-and-after study from the Netherlands found that northern lapwingpopulation trends changed from decreases to increases following the introduction of mosaic management. Three other species of wading bird did not show such a response and Eurasian oystercatcher populations did less well under mosaic management than other management types.
A replicated, paired sites study in the Netherlands that black-tailed godwit had higher productivity under mosaic management than other management types due to higher nest survival, and nests were less likely to be trampled by livestock or destroyed by mowing under mosaic management.
We have captured no evidence for the effects of implementing food labelling schemes relating to biodiversity-friendly farming (organic, LEAF marque) on farmland wildlife.
'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.
One replicated study from Denmark showed that reducing the extent of grass pasture in leys reduced the undesirable uptake of nitrogen by grasses, therefore requiring lower rates of fertilizer for subsequent crops.
Pest damage:One controlled study from New Zealand found using parasitism rates to inform spraying decisions resulted in acceptable levels of crop damage from pests. Effects on natural enemy populations were not monitored.
Weeds: Six studies (including six randomised, replicated, controlled tests) from Asia, Europe and North America examined the effect of allelopathic plant remains on weeds by comparing amended soils with weeded controls. Three studies found a reduction in weed growth, and three found effects varied between years, weed groups, or the type of weeding method in controls. Four studies from Asia and North America examined the effect on weeds by comparing amended soils with unweeded controls. Two studies found a reduction in weed growth, but one found that residues applied too far in advance of crop planting had the reverse effect. Two studies found that effects varied between trials, weed species or the type of residue used. Two studies, including one randomised, replicated, controlled laboratory study, found that the decrease in weeds did not last beyond a few days or weeks after residue incorporation. Pests:One randomised, replicated, controlled study in the Philippines found mixed effects on pests. Crop growth:Two of three studies found crop growth was inhibited by allelopathic plant remains, but this could be minimised by changing the timing of application. One study found effects varied between years. Yield: Three randomised, replicated, controlled studies compared yields in amended plots with weeded controls and found positive, negative and mixed effects. Three studies compared amended plots with unweeded controls, two found positive effects on yield and one found mixed effects (depending on the crop). Profit: One study found that amending soils increased profit compared to unweeded controls, but not compared to weeded controls.
One replicated controlled trial on lowland farms in Scotland showed that grassy field margins attracted nest-searching queen bumblebees in spring at higher densities than cropped field margins, managed or unmanaged grasslands or hedgerows.
All four studies (including one replicated, controlled study and one review) from Belgium, Germany, Hungary and unspecified European countries reported a positive effect of crop rotations on ground beetles or plants. Three studies found higher ground beetle species richness and/or abundance and one study found higher plant species richness in rotation fields or on farms with more crops in rotation compared to monoculture fields.
A study from Hungary found that fields in monoculture had a more stable and abundant ground beetle community than fields within a rotation.
One large replicated controlled trial showed that the average abundance of long-tongued bumblebees on field margins was positively correlated with the number of pollen and nectar agri-environment agreements in a 10 km grid square.
Of four studies captured, one, a replicated and controlled paired sites study from Australia, found that farms with plantings of native vegetation held more species than those without. The effect was smaller than that explained by variation in the amount of natural habitat remaining on farms. A replicated study from Switzerland found more species in areas under the Ecological Compensation Area scheme than areas not under it.
A before-and-after study from Switzerland found that the populations of three bird species increased after an increase in the amount of land under the Ecological Compensation Scheme. This study found that three species were more found more than expected on Ecological Compensation Scheme land. Another replicated study from Switzerland found that some habitats held more birds if they were close to ECA habitat but that the amount of Ecological Compensation Scheme in an area had no impact on population densities.
A small study from the UK found no effect of habitat creation on grey partridge populations.