Turning points of global anthropogenic nitrogen creation and their climate effect

Baojing Gu1,2,*, Xiaotang Ju3, Yiyun Wu2, Jan Willem Erisman4,5, Albert Bleeker6, Stefan Reis7,8, Mark A. Sutton7, Shu Kee Lam9, Oene Oenema10, Rognvald Smith7, Deli Chen9, Xinyue Ye11

1Department of Land Management, Zhejiang University, Hangzhou 310058, PR China

2Policy Simulation Laboratory, Zhejiang University, Hangzhou 310058, PR China

3College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, PR China

4Louis Bolk Institute, Hoofdstraat 24, 3972 LA Driebergen, The Netherlands

5VU Amsterdam, De Boelelaan 1091, 1081 HV Amsterdam, The Netherlands

6Netherlands Environmental Assessment Agency (PBL), Postbus 30314, The Netherlands

7NERC Centre for Ecology & Hydrology, Bush Estate, Penicuik, Midlothian, EH26 0QB, United Kingdom

8University of Exeter Medical School, Knowledge Spa, Truro, TR1 3HD, United Kingdom

9Crop and Soil Science Section, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Victoria 3010 Australia

10Department of Soil Quality, Wageningen University, P.O. Box 47, 6700 AA, Wageningen, The Netherlands

11Department of Geography, Kent State University, Kent, OH 44242, USA

 

Abstract

Reactive nitrogen (Nr) is both a limiting nutrient for food production and a major cause of global environmental and climate change. Managing Nr is crucial for its sustainable use in an increasingly affluent society (Zhang et al., 2015), especially as it may compromise the mitigation of global warming through interactions with the carbon cycle (Zaehle et al., 2011). The relation between Nr creation/release and carbon dioxide (CO2) emission/sequestration with respect to economic growth remains uncertain. Here we report on the turning points of Nr creation and release, and CO2 emission in relation to the growth of gross domestic product (GDP) per capita. Nr creation increases with GDP per capita until reaching a turning point, after which it tends to decrease with further economic growth. A similar pattern is noted for CO2 emission and Nr release to the atmosphere. However, the ratio of CO2 emission to Nr release to the atmosphere increases with economic growth without any turning point. This phenomenon suggests that the carbon sink in terrestrial ecosystems will be limited by Nr availability with economic growth in the future, and managing Nr for sustainable development may compromise the mitigation of global warming. Integrated management of carbon and Nr is therefore critical for future sustainable development and mitigation to climate warming.