Smoothing the Phosphorus Resource Stress under the Socioeconomic Development in China

Phosphorus (P) is the key in maintaining food security
and ecosystem
functions. Population growth and economic development have increased
the demand for phosphate rocks. China has gradually developed from
zero phosphate mining to the world’s leading P miner, fertilizer,
and agricultural producer since 1949. China released policies, such
as designating phosphate rock as a strategic resource, promoting eco-agricultural
policies, and encouraging the use of solid wastes produced in mining
and the phosphorus chemical industry as construction materials. However,
methodological and data gaps remain in the mapping of the long-term
effects of policies on P resource efficiency. Here, P resource efficiency
can be represented by the potential of the P cycle to concentrate
or dilute P as assessed by substance flow analysis (SFA) complemented
by statistical entropy analysis (SEA). P-flow quantification over
the past 70 years in China revealed that both resource utilization
and waste generation peaked around 2015, with 20 and 11 Mt of mined
and wasted P, respectively. Additionally, rapidly increasing aquaculture
wastewater has exacerbated pollution. The resource efficiency of the
Chinese P cycle showed a U-shaped change with an overall improvement
of 22.7%, except for a temporary trough in 1975. The driving force
behind the efficiency decline was the roaring phosphate fertilizer
industry, as confirmed by the sharp increase in P flows for both resource
utilization and waste generation from the mid-1960s to 1975. The positive
driving forces behind the 30.7% efficiency increase from 1975 to 2018
were the implementation of the resource conservation policy, downstream
pollution control, and, especially, the circular agro-food system
strategy. However, not all current management practices improve the
P resource efficiency. Mixing P industry waste with construction materials
and the development of aquaculture to complement offshore fisheries
erode P resource efficiency by 2.12% and 9.19%, respectively. With
the promotion of a zero-waste society in China, effective P-cycle
management is expected.