Human Perturbation of the Global Phosphorus Cycle: Changes and Consequences

• DOI: 10.1021/acs.est.7b03910
• Publication Date: 2018-02-06T03:09:03Z
• Authors: Zengwei Yuan; Songyan Jiang; Hu Sheng; Xin Liu; Hui Hua; Xuewei Liu; You Zhang
• Keywords: 2. Zero hunger; Nitrogen; Phosphorus; Eutrophication; 15. Life on land; 01 natural sciences; 6. Clean water; 13. Climate action; Humans; Fertilizers; Ecosystem; 0105 earth and related environmental sciences

The phosphorus (P) cycle is an important Earth system process. While natural P mobilization is slow, humans have been altering P cycle by intensifying P releases from lithosphere to ecosystems. Here, we examined magnitudes of which humans have altered the P cycles by integrating the estimates from recent literatures, and furthermore illustrated the consequences. Based on our synthesis, human alterations have tripled the global P mobilization in land-water continuum and increased P accumulation in soil with 6.9 ± 3.3 Tg-P yr-1. Around 30% of atmospheric P transfer is caused by human activities, which plays a significant role than previously thought. Pathways involving with human alterations include phosphate extraction, fertilizers application, wastes generation, and P losses from cropland. This study highlights the importance of sustainable P supply as a control on future food security because of regional P scarcity, food demand increase and continuously P intensive food production. Besides, accelerated P loads are responsible for enhanced eutrophication worldwide, resulting in water quality impairment and aquatic biodiversity losses. Moreover, the P enrichment can definitely stimulate the cycling of carbon and nitrogen, implying the great need for incorporating P in models predicting the response of carbon and nitrogen cycles to global changes.