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A novel method to estimate the response of habitat types to nitrogen deposition
2024
Wamelink, G.W.W. | Goedhart, P.W. | Roelofsen, H.D. | Bobbink, R. | Posch, M. | van Dobben, H.F. | Biurrun, I. | Bonari, G. | Dengler, J. | Dítě, D. | Garbolino, E. | Jansen, J. | Jašková, A.K. | Lenoir, J. | Peterka, T. | Radboud University [Nijmegen] | Coordination Centre for Effects ; Coordination Centre for Effects | UNIVERSITY OF THE BASQUE COUNTRY BILBAO DEPARTMENT OF PLANT BIOLOGY AND ECOLOGY ESP ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | University of Bayreuth | Institut Supérieur d'Ingénierie et de Gestion de l'Environnement (ISIGE) ; Mines Paris - PSL (École nationale supérieure des mines de Paris) ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL) | Public Health England [London] | Ecologie et Dynamique des Systèmes Anthropisés - UMR CNRS 7058 (EDYSAN) ; Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS) | Masaryk University [Brno] (MUNI)
International audience | Increasing nitrogen depositions adversely affect European landscapes, including habitats within the Natura2000 network. Critical loads for nitrogen deposition have been established to quantify the loss of habitat quality. When the nitrogen deposition rises above a habitat-specific critical load, the quality of the focal habitat is expected to be negatively influenced. Here, we investigate how the quality of habitat types is affected beyond the critical load. We calculated response curves for 60 terrestrial habitat types in the Netherlands to the estimated nitrogen deposition (EMEP-data). The curves for habitat types are based on the occurrence of their characteristic plant species in North-Western Europe (plot data from the European Vegetation Archive). The estimated response curves were corrected for soil type, mean annual temperature and annual precipitation. Evaluation was carried out by expert judgement, and by comparison with gradient deposition field studies. For 39 habitats the response to nitrogen deposition was judged to be reliable by five experts, while out of the 41 habitat types for which field studies were available, 25 showed a good agreement. Some of the curves showed a steep decline in quality and some a more gradual decline with increasing nitrogen deposition. We compared the response curves with both the empirical and modelled critical loads. For 41 curves, we found a decline already starting below the critical load.
Show more [+] Less [-]Effects of elevated ozone concentration and nitrogen addition on ammonia stomatal compensation point in a poplar clone
2018
Xu, Wen | Shang, Bo | Xu, Yansen | Yuan, Xiangyang | Dore, Anthony J. | Zhao, Yuanhong | Massad, Raia Silvia | Feng, Zhaozhong | State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences ; Chinese Academy of Sciences [Beijing] (CAS) | College of Resources and Environment ; Shanxi Agricultural University [Jinzhong] | Bush Estate, Penicuik, Midlothian, EH26 0QB ; Centre for Ecology and Hydrology | Laboratory for Climate and Ocean-Atmosphere Sciences [Peking] ; Department of Atmospheric and Oceanic Sciences [Peking] ; Peking University [Beijing]-Peking University [Beijing] | Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Université Paris-Saclay
The stomatal compensation point of ammonia (χs) is a key factor controlling plant-atmosphere NH3 exchange, which is dependent on the nitrogen (N) supply and varies among plant species. However, knowledge gaps remain concerning the effects of elevated atmospheric N deposition and ozone (O3) on χs for forest species, resulting in large uncertainties in the parameterizations of NH3 incorporated into atmospheric chemistry and transport models (CTMs). Here, we present leaf-scale measurements of χs for hybrid poplar clone ‘546’ (Populusdeltoides cv. 55/56 x P. deltoides cv. Imperial) growing in two N treatments (N0, no N added; N50, 50 kg N ha−1 yr−1 urea fertilizer added) and two O3 treatments (CF, charcoal-filtered air; E-O3, non-filtered air plus 40 ppb) for 105 days. Our results showed that χs was significantly reduced by E-O3 (41%) and elevated N (19%). The interaction of N and O3 was significant, and N can mitigate the negative effects of O3 on χs. Elevated O3 significantly reduced the light-saturated photosynthetic rate (Asat) and chlorophyll (Chl) content and significantly increased intercellular CO2 concentrations (Ci), but had no significant effect on stomatal conductance (gs). By contrast, elevated N did not significantly affect all measured photosynthetic parameters. Overall, χs was significantly and positively correlated with Asat, gs and Chl, whereas a significant and negative relationship was observed between χs and Ci. Our results suggest that O3-induced changes in Asat, Ci and Chl may affect χs. Our findings provide a scientific basis for optimizing parameterizations of χs in CTMs in response to environmental change factors (i.e., elevated N deposition and/or O3) in the future.
Show more [+] Less [-][Reduction of ammonia emissions] | Reduction des emissions d'ammoniac: inventer la vache nucleaire?
1999
Jagusiewicz, A.
La reduction des emissions d'ammoniac pour atteindre des objectifs environnementaux tels que stopper la diminution de la superficie des ecosystemes non proteges contre l'acidification et l'eutrophisation va occuper une place de plus en plus importante dans la strategie de lutte contre la pollution. En raison de la reduction des emissions d'oxydes de soufre et d'azote operee au cours des 20 dernieres annees dans le cadre de la Convention sur la pollution atmospherique transfrontiere a longue distance, il est fort probable qu'en 2010 c'est l'ammoniac qui contribuera le plus aux emissions gazeuses responsables de l'eutrophisation et de l'acidification. D'ou l'importance de prendre des maintenant des mesures efficaces contre ce polluant, et ce a l'echelle continentale
Show more [+] Less [-]Nitrate reductase activity in aquatic plants as an indicator of ammoniacal nitrogen contamination
1995
Rolland, T. (Institut de Botanique, Strasbourg (France). Laboratoire de Botanique et d'Ecologie Vegetale) | Robach, F. | Tremolieres, M. | Dester, S.