A study of the nitrogen and phosphorus imbalance in East Asia based on the distribution patterns of and stoichiometric variation in global atmospheric nitrogen and phosphorus

Abstract

To explore nitrogen (N) and phosphorus (P) imbalances in the atmosphere in East Asia, we set up an atmospheric sampling station at the southern end of the East China Sea. From April 2019 to March 2020, we collected atmospheric particulates and rainwater samples and performed chemical analyses of inorganic and organic N and P species in the samples. In this study, the average N/P ratio of dry deposition was 443 +/- 366, and it was affected mainly by changes in the wind direction in different seasons. The average N/P ratio of wet deposition was 333 +/- 362, and the distribution of the ratio was affected mainly by rainfall. In addition, this study categorized the global N and P fluxes into four distribution patterns: high N and high P (HNHP), high N and low P (HNLP), low N and high P (LNHP), and low N and low P (LNLP). The Galloway/ Mahowald ratio (G/M ratio) ranges and distribution areas of these four types are 450-2200 (Western Europe, southeastern South America), 660-4400 (East Asia, North America), 0.2-200 (Southern Europe, North Africa) and 45-450 (South Asia). Among them, mainland China in East Asia (HNLP) usually has a higher G/M ratio. The study area has the same characteristics as most HNLP regions (coastal China and the southeastern coast of North America). This study also highlights the imbalance in the ratio of N to P caused by excessive active N emissions from human activities.