TY - JOUR

T1 - Herbivore and pollinator responses to grassland management intensity along experimental changes in plant species richness

AU - Hudewenz, Anika

AU - Klein, Alexandra-Maria

AU - Scherber, Christoph

AU - Stanke, Lea

AU - Tscharntke, Teja

AU - Vogel, Anja

AU - Weigelt, Alexandra

AU - Weisser, Wolfgang W.

AU - Ebeling, Anne

PY - 2012/6/1

Y1 - 2012/6/1

N2 - Agricultural intensification is a major driver of global environmental change. Disentangling the relative impact of losses in plant species richness and intensified management on higher trophic level organisms is important for conservation recommendations.We established different management regimes along an experimental gradient of plant species richness within “The Jena-Experiment” in Germany and quantified herbivory as well as grasshoppers and pollinators. Herbivory, grasshopper density and species richness and frequency of flower visiting pollinators were recorded two times in each of four subplots of altogether 80 plots differing in plant species richness. Each of the four subplots was subject to four different levels of fertilizer application and mowing to simulate very low, low, high and very high land use intensity.Fertilization and mowing significantly affected plant–herbivore interactions but plant species richness had no discernible effect. Grasshoppers were most abundant at high intensity subplots (3.1 individuals per m2) and least abundant on very low intensity subplots (1.3 individuals per m2). Leaf damage caused by herbivores was highest in even the very high intensity subplots (3.7%) with four mowing events per year and high amounts of fertilizer application and lowest on subplots with a low management intensity (2.4%) comprising two mowing events per year but no fertilizer application. In contrast, pollinators benefited most from lower management intensities, with only one or two mowing events and no fertilizer addition. In addition, higher numbers of flowering plant species and increased blossom cover was associated with enhanced pollinator species richness and flower visitation.Our results indicate that even in grasslands with high plant species richness, mowing and fertilization are more important drivers of herbivory and flower visitation by pollinators. Management with no more than two cuts per year and without fertilizer application in our grasslands balanced the ecosystem functions of increased pollination and decreased herbivory.

AB - Agricultural intensification is a major driver of global environmental change. Disentangling the relative impact of losses in plant species richness and intensified management on higher trophic level organisms is important for conservation recommendations.We established different management regimes along an experimental gradient of plant species richness within “The Jena-Experiment” in Germany and quantified herbivory as well as grasshoppers and pollinators. Herbivory, grasshopper density and species richness and frequency of flower visiting pollinators were recorded two times in each of four subplots of altogether 80 plots differing in plant species richness. Each of the four subplots was subject to four different levels of fertilizer application and mowing to simulate very low, low, high and very high land use intensity.Fertilization and mowing significantly affected plant–herbivore interactions but plant species richness had no discernible effect. Grasshoppers were most abundant at high intensity subplots (3.1 individuals per m2) and least abundant on very low intensity subplots (1.3 individuals per m2). Leaf damage caused by herbivores was highest in even the very high intensity subplots (3.7%) with four mowing events per year and high amounts of fertilizer application and lowest on subplots with a low management intensity (2.4%) comprising two mowing events per year but no fertilizer application. In contrast, pollinators benefited most from lower management intensities, with only one or two mowing events and no fertilizer addition. In addition, higher numbers of flowering plant species and increased blossom cover was associated with enhanced pollinator species richness and flower visitation.Our results indicate that even in grasslands with high plant species richness, mowing and fertilization are more important drivers of herbivory and flower visitation by pollinators. Management with no more than two cuts per year and without fertilizer application in our grasslands balanced the ecosystem functions of increased pollination and decreased herbivory.

KW - Ecosystems Research

KW - bees

KW - ecosystem functions

KW - fertilization

KW - grasshoppers

KW - land use

KW - mowing

KW - bees

KW - ecosystem functions

KW - fertilization

KW - grasshoppers

KW - land use

KW - Mowing

KW - Biology

KW - bees

KW - ecosystem functions

KW - fertilization

KW - grasshoppers

KW - land use

KW - mowing

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-84860222034&origin=inward&txGid=0

U2 - 10.1016/j.biocon.2012.02.024

DO - 10.1016/j.biocon.2012.02.024

M3 - Journal articles

VL - 150

SP - 42

EP - 52

JO - Biological Conservation

JF - Biological Conservation

SN - 0006-3207

IS - 1

ER -