Imbalanced atmospheric nitrogen and phosphorus depositions in China: Implications for nutrient limitation

• Published in: Journal of geophysical research. Biogeosciences Vol. 121; no. 6; pp. 1605 - 1616
• Main Authors: Zhu, Jianxing, Wang, Qiufeng, He, Nianpeng, Smith, Melinda D., Elser, James J., Du, Jiaqiang, Yuan, Guofu, Yu, Guirui, Yu, Qiang
• Format: Journal Article
• Language: English
• Published: Washington Blackwell Publishing Ltd 01-06-2016
• Subjects: Aquatic ecosystems; Atmospheric chemistry; ecological stoichiometry; Energy consumption; Fertilizers; N:P; Nitrogen; Nutrient availability; Nutrient balance; nutrient limitation; Phosphorus; Terrestrial ecosystems; Wet deposition; China, People's Rep., Inner Mongolia; China, People's Rep
• ISSN: 2169-8953; 2169-8961
• DOI: 10.1002/2016JG003393

Atmospheric wet nitrogen (N) and phosphorus (P) depositions are important sources of bioavailable N and P, and the input of N and P and their ratios significantly influences nutrient availability and balance in terrestrial as well as aquatic ecosystems. Here we monitored atmospheric P depositions by measuring monthly dissolved P concentration in rainfall at 41 field stations in China. Average deposition fluxes of N and P were 13.69 ± 8.69 kg N ha−1 a−1 (our previous study) and 0.21 ± 0.17 kg P ha−1 a−1, respectively. Central and southern China had higher N and P deposition rates than northwest China, northeast China, Inner Mongolia, or Qinghai‐Tibet. Atmospheric N and P depositions showed strong seasonal patterns and were dependent upon seasonal precipitation. Fertilizer and energy consumption were significantly correlated with N deposition but less correlated with P deposition. The N:P ratios of atmospheric wet deposition (with the average of 77 ± 40, by mass) were negatively correlated with current soil N:P ratios in different ecological regions, suggesting that the imbalanced atmospheric N and P deposition will alter nutrient availability and strengthen P limitation, which may further influence the structure and function of terrestrial ecosystems. The findings provide the assessments of both wet N and P deposition and their N:P ratio across China and indicate potential for strong impacts of atmospheric deposition on broad range of terrestrial ecosystems.
Key Points
Rates of atmospheric wet deposition of N and P were 13.69 and 0.21 kg ha‐1 a‐1 with a N:P ratio (by mass) of 77 in China
Regional fertilizer and energy consumption correlated strongly with N deposition but had a limited effect on P deposition
N:P ratios of atmospheric wet deposition were negatively correlated with soil N:P ratios in ecological regions