二氧化碳排放过多会推动全球变暖，对此人们已有很多认识。但美国科学家呼吁，应同时加大对活性氮的关注，因为这种物质正在自然环境中快速积累，对环境的危害越来越大，可能不亚于二氧化碳。
美国研究人员在新一期《科学》杂志上撰文说，氮气的化学性质不活泼，不易发生化学反应。但活性氮却很活跃，进入大气后其形成的氮化物如果过度积累能带来烟雾和酸雨，破坏臭氧层，并加剧全球变暖，因此活性氮在很多方面都像二氧化碳一样会带来“大问题”。
参与研究的弗吉尼亚大学教授詹姆斯·加洛韦指出，目前活性氮在自然环境中的积累速度“惊人”，所带来的威胁非常严重，可能“不亚于二氧化碳”。
氮化物主要是在使用氮肥和燃烧化石燃料的过程中产生的。研究人员说，如何在有效控制二氧化碳和氮化物排放的同时又不影响粮食生产和保证能源供应，将是人类面临的严峻挑战。
生物谷推荐原始出处：
Science，Vol. 320. no. 5878, pp. 889 - 892，James N. Galloway, Mark A. Sutton
Transformation of the Nitrogen Cycle: Recent Trends, Questions, and Potential Solutions
James N. Galloway,1* Alan R. Townsend,2 Jan Willem Erisman,3 Mateete Bekunda,4 Zucong Cai,5 John R. Freney,6 Luiz A. Martinelli,7 Sybil P. Seitzinger,8 Mark A. Sutton9
Humans continue to transform the global nitrogen cycle at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land to cause a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen-containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste.
1 Environmental Sciences Department, University of Virginia, Charlottesville, VA 22904, USA.
2 Institute of Arctic and Alpine Research and Department of Ecology and Evolutionary Biology, Campus Box 450, University of Colorado, Boulder, CO 80309, USA.
3 Energy Research Centre of the Netherlands, ECN, Post Office Box 1, 1755 ZG Petten, Netherlands.
4 Faculty of Agriculture, Makerere University, Post Office Box 7062, Kampala, Uganda.
5 Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
6 Commonwealth Scientific and Industrial Research Organisation Plant Industry, GPO Box 1600, Canberra, A.C.T., Australia.
7 Centro de Energia Nuclear na Agricultura-Universidade de São Paulo, Avenida Centenario, 303, Piracicaba-SP, Brazil.
8 Rutgers, The State University of New Jersey, Institute of Marine and Coastal Sciences, Rutgers/National Oceanic and Atmospheric Administration Cooperative Marine Education and Research Program, New Brunswick, NJ 08901, USA.
9 Centre for Ecology and Hydrology, Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH26 0QB, UK.
