Can above-ground ecosystem services compensate for reduced fertilizer input and soil organic matter in annual crops?

TY - JOUR

T1 - Can above-ground ecosystem services compensate for reduced fertilizer input and soil organic matter in annual crops?

AU - van Gils, Stijn

AU - van der Putten, Wim H

AU - Kleijn, David

N1 - 6043, TE; Data archiving: data archived at Dryad

PY - 2016

Y1 - 2016

N2 - 1.Above-ground and below-ground environmental conditions influence crop yield by pollination, pest pressure, and resource supply. However, little is known about how interactions between these factors contribute to yield. Here, we used oilseed rape Brassica napus to test their effects on crop yield.2.We exposed potted plants to all combinations of high and low levels of soil organic matter (SOM) and fertilizer supply, and placed all treatments at a variety of field sites representing a gradient in pollinator visitation rate and pest exposure. We determined the relative contribution of pollinators and pests, SOM and fertilizer supply to yield. We also tested whether SOM can moderate effects of fertilizer on yield and whether soil conditions influence the relationship between above-ground conditions and yield.3.Increases in pollinator visitation rate and decreases in pest pressure enhanced yield more than increase of fertilizer supply. Although higher SOM content resulted in plants with more biomass and flowers, under our experimental conditions SOM neither enhanced yield, nor influenced effects of fertilizer, pollinators or pests on yield.4.The relationships between yield, pollinator visitation rate and pest pressure did not depend on the level of fertilization suggesting that the effects of fertilizer application and above-ground (dis)services on yield were additive. In contrast, pollinator visitation rate was more strongly related to yield at low pest pressure than at high pest pressure indicating trade-offs between above-ground services and disservices.5.Synthesis and applications. Our results show that it is possible to increase oilseed rape yield by enhancing pollination, irrespective of supplying mineral fertilizer. Moreover, the fact that below-ground conditions did not alter the effect of above-ground conditions, suggests that farmers may obtain even higher yields by maximizing both above-ground ecosystem services and external inputs. Further studies are needed to understand at which point the positive relationships between pollinator visitation and yield, as well as between fertilizer and yield will level off. Considering above-ground and below-ground services and inputs in agro-ecosystems in conjunction is crucial in order to optimize external inputs for crop yield from an economic and ecological perspective.This article is protected by copyright. All rights reserved.

AB - 1.Above-ground and below-ground environmental conditions influence crop yield by pollination, pest pressure, and resource supply. However, little is known about how interactions between these factors contribute to yield. Here, we used oilseed rape Brassica napus to test their effects on crop yield.2.We exposed potted plants to all combinations of high and low levels of soil organic matter (SOM) and fertilizer supply, and placed all treatments at a variety of field sites representing a gradient in pollinator visitation rate and pest exposure. We determined the relative contribution of pollinators and pests, SOM and fertilizer supply to yield. We also tested whether SOM can moderate effects of fertilizer on yield and whether soil conditions influence the relationship between above-ground conditions and yield.3.Increases in pollinator visitation rate and decreases in pest pressure enhanced yield more than increase of fertilizer supply. Although higher SOM content resulted in plants with more biomass and flowers, under our experimental conditions SOM neither enhanced yield, nor influenced effects of fertilizer, pollinators or pests on yield.4.The relationships between yield, pollinator visitation rate and pest pressure did not depend on the level of fertilization suggesting that the effects of fertilizer application and above-ground (dis)services on yield were additive. In contrast, pollinator visitation rate was more strongly related to yield at low pest pressure than at high pest pressure indicating trade-offs between above-ground services and disservices.5.Synthesis and applications. Our results show that it is possible to increase oilseed rape yield by enhancing pollination, irrespective of supplying mineral fertilizer. Moreover, the fact that below-ground conditions did not alter the effect of above-ground conditions, suggests that farmers may obtain even higher yields by maximizing both above-ground ecosystem services and external inputs. Further studies are needed to understand at which point the positive relationships between pollinator visitation and yield, as well as between fertilizer and yield will level off. Considering above-ground and below-ground services and inputs in agro-ecosystems in conjunction is crucial in order to optimize external inputs for crop yield from an economic and ecological perspective.This article is protected by copyright. All rights reserved.

KW - agro-ecosystem, Brassica napus, crop yield, Evergestis extimalis, Fertilizer, insect pests, oilseed rape, pollination, rapeseed, soil organic matter

KW - national

UR - http://dx.doi.org/10.5061/dryad.s08f7

U2 - 10.1111/1365-2664.12652

DO - 10.1111/1365-2664.12652

M3 - Article

SN - 1365-2664

VL - 53

SP - 1186

EP - 1194

JO - Journal of Applied Ecology

JF - Journal of Applied Ecology

IS - 4

ER -