Plant phenology, growth and nutritive quality of Briza maxima: Responses induced by enhanced ozone atmospheric levels and nitrogen enrichment

Consistent ozone-induced decreases in pasture forage quality across several grassland types and consequences for UK lamb production

“…This is in agreement with previous studies where the ADF, NDF and lignin content increased with elevated ozone in T. subterraneum (Sanz et al, 2005) and Briza maxima (Sanz et al, 2011), and increased lignin content was found in T. repens and T. pratense exposed to ozone in a free-air fumigation system . Some other studies have shown that the content of 'desirable' parameters such as protein can also increase with increasing ozone exposure (e.g.…”

Assessing the impacts of intra- and interspecific competition betweenTriticum aestivumandTrifolium repenson the species’ responses to ozone

“…Ozone produced visible injury in both species; however, reduction of leaf area and biomass per plant was larger for clover than for wheat, suggesting that wheat was more tolerant to ozone than clover. This is concurrent with past literature showing higher susceptibility of Fabaceae (legume) species to ozone (Gimeno et al 2004b;Sanz et al 2011). …”

Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the response

“…On the other hand, N seemed to counterbalance O3 yield reductions when pollutant levels were moderate, but this compensation was not observed in the high O3 exposure treatment. A similar positive influence of N on O3 effects on yield and quality parameters has been already detected when annual plants have been tested individually (Sanz et al" 2005(Sanz et al" , 2011. Other authors have highlighted the importance of nutrient availability in modifying O3 responses of semi-natural vegetation (Bassin et al, 2007) but these interactions need further characterization in different vegetation types.…”

“…These ecosystems are protected by the 92/43/ EEC Habitat Directive and included in the Nature 2000 network. Previous experiments with individual species grown in pots showed that O3 induces visible injury, accelerates senescence and reduces biomass production and consumable food value of some representative species (Bermejo et al, 2003;Gimeno et al, 2004a,b;Sanz et al, 2005Sanz et al, , 2007Sanz et al, , 2011. Interestingly, nitrogen fixing legumes, with high nutritive quality for herbivorous feeding, were more O3 sensitive than grasses (Bermejo et al, 2003;Gimeno et al, 2004a).…”

“…Moreover, O3 strongly reduced flower and seed production of some sensitive legumes (Gimeno et al, 2004b;Sanz et al, 2007) which could interfere with species perpetuation and competitive fitness. For some species, N fertilization counterbalanced O3 effects on senescence and plant and flower biomass, when plants were exposed to moderate O3 concentrations (Sanz et al, 2005(Sanz et al, , 2011. Experiments with annual plant communities are needed to test if results obtained with individual species grown in pots are applicable for O3 risk assessment to annual grassland communities.…”