TY - JOUR

T1 - Enhanced nitrogen deposition exacerbates the negative effect of increasing background ozone in Dactylis glomerata, but not Ranunculus acris

AU - Wyness, Kirsten

AU - Hydrology, Centre for Ecology

AU - Hydrology, Centre for Ecology

AU - University;, Newcastle

AU - Jones, Davey L.

PY - 2011/10/1

Y1 - 2011/10/1

N2 - The combined impacts of simulated increased nitrogen (N) deposition (75 kg N ha−1 yr−1) and increasing background ozone (O3) were studied using two mesotrophic grassland species (Dactylis glomerata and Ranunculus acris) in solardomes, by means of eight O3 treatments ranging from 15.5 ppb to 92.7 ppb (24 h average mean). A–Ci curves were constructed for each species to gauge effects on photosynthetic efficiency and capacity, and effects on biomass partitioning were determined after 14 weeks. Increasing the background concentration of O3 reduced the healthy above ground and root biomass of both species, and increased senesced biomass. N fertilisation increased biomass production in D. glomerata, and a significantly greater than additive effect of O3 and N on root biomass was evident. In contrast, R. acris biomass was not affected by high N. The study shows the combined effects of these pollutants have differential implications for carbon allocation patterns in common grassland species.

AB - The combined impacts of simulated increased nitrogen (N) deposition (75 kg N ha−1 yr−1) and increasing background ozone (O3) were studied using two mesotrophic grassland species (Dactylis glomerata and Ranunculus acris) in solardomes, by means of eight O3 treatments ranging from 15.5 ppb to 92.7 ppb (24 h average mean). A–Ci curves were constructed for each species to gauge effects on photosynthetic efficiency and capacity, and effects on biomass partitioning were determined after 14 weeks. Increasing the background concentration of O3 reduced the healthy above ground and root biomass of both species, and increased senesced biomass. N fertilisation increased biomass production in D. glomerata, and a significantly greater than additive effect of O3 and N on root biomass was evident. In contrast, R. acris biomass was not affected by high N. The study shows the combined effects of these pollutants have differential implications for carbon allocation patterns in common grassland species.

KW - Ozone

KW - Nitrogen

KW - Root:shoot ratio

KW - Grassland

KW - Carbon allocation

U2 - 10.1016/j.envpol.2011.06.022

DO - 10.1016/j.envpol.2011.06.022

M3 - Article

VL - 159

SP - 2493

EP - 2499

JO - Environmental Pollution

JF - Environmental Pollution

SN - 0269-7491

IS - 10

ER -