China’s improving inland surface water quality since 2003

Ma, Ting; Zhao, Na; Ni, Yi; Yi, Jiawei; Wilson, John P.; He, Lihuan; Du, Yunyan; Pei, Tao; Zhou, Chenghu; Ci, Song; Cheng, Weiming

doi:10.1126/sciadv.aau3798

Cited by 130 publications

(47 citation statements)

References 44 publications

(50 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Chinese state and local government have invested thousands of billions of Chinese Yuan to enhance wastewater treatment and control pollution sources dedicated to environmental restoration in the recent decade 37 . Contributions of the investments on the improved surface water quality (characterized mainly by COD and NH + 4 -N concentrations) and the regional difference were quantified in a recent study 46 . Notwithstanding a recent trend in improved water quality, our results show that quality still presents a great issue for achieving safe water supply in China.…”

Section: Discussionmentioning

confidence: 99%

Pollution exacerbates China’s water scarcity and its regional inequality

et al. 2020

Self Cite

View full text Add to dashboard Cite

Inadequate water quality can mean that water is unsuitable for a variety of human uses, thus exacerbating freshwater scarcity. Previous large-scale water scarcity assessments mostly focused on the availability of sufficient freshwater quantity for providing supplies, but neglected the quality constraints on water usability. Here we report a comprehensive nationwide water scarcity assessment in China, which explicitly includes quality requirements for human water uses. We highlight the necessity of incorporating water scarcity assessment at multiple temporal and geographic scales. Our results show that inadequate water quality exacerbates China's water scarcity, which is unevenly distributed across the country. North China often suffers water scarcity throughout the year, whereas South China, despite sufficient quantities, experiences seasonal water scarcity due to inadequate quality. Over half of the population are affected by water scarcity, pointing to an urgent need for improving freshwater quantity and quality management to cope with water scarcity.

show abstract

Section: Discussionmentioning

confidence: 99%

Pollution exacerbates China’s water scarcity and its regional inequality

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Discharges. Shifts in anthropogenic nutrient discharges from the surrounding watershed are usually responsible for alterations of lake nutrient conditions (8,33,34). We therefore characterized temporal changes in N and P discharges of the five anthropogenic sources listed here with a spatial resolution of 1 km 2 during 2008 to 2017 in China (SI Appendix, Supplementary Text S1).…”

Section: Response Of Lake Nutrient Regime To Shifting Anthropogenicmentioning

confidence: 99%

“…This volume of wastewater is continuing to grow with urbanization and the associated population increase (4). Increasing wastewater production, together with inadequate collection and treatment facilities, have led to negative impacts on water quality, biodiversity, and overall functioning of the receiving aquatic ecosystem (6)(7)(8). For instance, nitrogen (N) produced by human excreta accounts for ∼15% to 20% of total anthropogenic production of reactive N per year (4), while phosphorus (P) produced by human excreta represents ∼25% of worldwide P demand (4,9).…”

mentioning

confidence: 99%

“…For instance, nitrogen (N) produced by human excreta accounts for ∼15% to 20% of total anthropogenic production of reactive N per year (4), while phosphorus (P) produced by human excreta represents ∼25% of worldwide P demand (4,9). Many developing countries are tackling the problem of excess nutrients by increasing municipal wastewater treatment capacity (10)(11)(12)(13), which is often more achievable than reducing nonpoint nutrient sources through reducing fertilizer application rates and watershed conservation practice (7,8,14). China, with an annual municipal wastewater discharge of ∼60 × 10 9 m 3 , is a case in point (15).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Improvement in municipal wastewater treatment alters lake nitrogen to phosphorus ratios in populated regions

Tong

Wang

Peñuelas

et al. 2020

Proc. Natl. Acad. Sci. U.S.A.

154

View full text Add to dashboard Cite

Large-scale and rapid improvement in wastewater treatment is common practice in developing countries, yet this influence on nutrient regimes in receiving waterbodies is rarely examined at broad spatial and temporal scales. Here, we present a study linking decadal nutrient monitoring data in lakes with the corresponding estimates of five major anthropogenic nutrient discharges in their surrounding watersheds over time. Within a continuous monitoring dataset covering the period 2008 to 2017, we find that due to different rates of change in TN and TP concentrations, 24 of 46 lakes, mostly located in China’s populated regions, showed increasing TN/TP mass ratios; only 3 lakes showed a decrease. Quantitative relationships between in-lake nutrient concentrations (and their ratios) and anthropogenic nutrient discharges in the surrounding watersheds indicate that increase of lake TN/TP ratios is associated with the rapid improvement in municipal wastewater treatment. Due to the higher removal efficiency of TP compared with TN, TN/TP mass ratios in total municipal wastewater discharge have continued to increase from a median of 10.7 (95% confidence interval, 7.6 to 15.1) in 2008 to 17.7 (95% confidence interval, 13.2 to 27.2) in 2017. Improving municipal wastewater collection and treatment worldwide is an important target within the 17 sustainable development goals set by the United Nations. Given potential ecological impacts on biodiversity and ecosystem function of altered nutrient ratios in wastewater discharge, our results suggest that long-term strategies for domestic wastewater management should not merely focus on total reductions of nutrient discharges but also consider their stoichiometric balance.

show abstract

“…Crop production will remain a key sector in mitigating DIN loads in the Yangtze and its tributaries because the discharge of point source pollution has been strictly controlled in recent years. 61 In our study, we soft-linked MARINA with the WOFOST model ( Figure 1). WOFOST can further be used to explore the crop-specific management (e.g., fertilization timing and amount) to support policies that aim to mitigate DIN in rivers.…”

Section: Model Uncertaintiesmentioning

confidence: 99%

Modeling the Contribution of Crops to Nitrogen Pollution in the Yangtze River

Chen

Strokal

Kroeze

et al. 2020

Environ. Sci. Technol.

View full text Add to dashboard Cite

Agriculture contributes considerably to nitrogen (N) inputs to the world's rivers. In this study, we aim to improve our understanding of the contribution of different crops to N inputs to rivers. To this end, we developed a new model system by linking the MARINA 2.0 (Model to Assess River Input of Nutrient to seAs) and WOFOST (WOrld FOod STudy) models. We applied this linked model system to the Yangtze as an illustrative example. The N inputs to crops in the Yangtze River basin showed large spatial variability. Our results indicate that approximately 6,000 Gg of N entered all rivers of the Yangtze basin from crop production as dissolved inorganic N (DIN) in 2012. Half of this amount is from the production of single rice, wheat, and vegetables, where synthetic fertilizers were largely applied. In general, animal manure contributes 12% to total DIN inputs to rivers. Threequarters of manure-related DIN in rivers are from vegetable, fruit, and potato production. The contributions of crops to river pollution differ among sub-basins. For example, potato is an important source of DIN in rivers of some upstream sub-basins. Our results may help to prioritize the dominant crop sources for management to mitigate N pollution in the future.

show abstract

China’s improving inland surface water quality since 2003

Abstract: China’s inland water quality has been markedly improved since 2003 notwithstanding regional variability.

Cited by 130 publications

References 44 publications

Pollution exacerbates China’s water scarcity and its regional inequality

Pollution exacerbates China’s water scarcity and its regional inequality

Improvement in municipal wastewater treatment alters lake nitrogen to phosphorus ratios in populated regions

Modeling the Contribution of Crops to Nitrogen Pollution in the Yangtze River

Contact Info

Product

Resources

About