Environmental Science, Management, Monitoring, Policy and Law, Soil Science, General Agricultural and Biological Sciences
60
Scopus Publications
Scopus Publications
Interplay of urbanization and agricultural modernization shapes nitrogen use in global croplands Sitong Wang, Xiuming Zhang, Ouping Deng, Baojing Gu Nature Communications, 2026 Urbanization reshapes agricultural systems through labor and land-use changes, interacting with modernization processes including farm size expansion, mechanization, and irrigation to drive nonlinear trends in cropland nitrogen use. Using a 61-year dataset from 139 countries, here we show that the association between urbanization and nitrogen outcomes is profoundly nonlinear and contingent on development stages. In low-income countries, urbanization initially increases fertilizer use while suppressing nitrogen yield and efficiency, though larger farm sizes mitigate these early losses. As countries reach upper-middle-income levels, modernization enhances nitrogen efficiency but introduces trade-offs between environmental gains and yield growth. In high-income countries, advanced modernization mitigates adverse urban impacts, reversing nitrogen use efficiency from a 4% decline to a 12% gain at high urbanization levels. These findings indicate that there is no universal sustainability pathway. Instead, integrating land consolidation, mechanization, and precision irrigation can transform urbanization into a catalyst for sustainable management and resilient food systems. Researchers show how modernization helps nations turn urbanization from a challenge into a catalyst for nitrogen efficiency. By integrating technology and land consolidation, countries can achieve sustainable farming in an increasingly urban world.
Managing livestock farm size to reduce nitrogen loss in China Luxi Cheng, Xiuming Zhang, Zhiping Zhu, Chenchen Ren, Chen Wang, Stefan Reis, Baojing Gu Resources Environment and Sustainability, 2026 The livestock farm size influences management strategies, affecting nitrogen use efficiency (NUE) and nitrogen losses. Using data from 360,000 farms across China in 2017, covering four major livestock types, the relationship between NUE, nitrogen losses, and farm size is examined. Results show that NUE increases and nitrogen loss intensity decreases as farm size grows for all livestock types, despite manure recycling ratios differ among livestock types, underscoring the need for tailored strategies to manage farm size. Managing farm size for only 16% of intensive farms nationwide could reduce nitrogen losses by 121 Gg (1 Gg=10 9 g), increase production by 21 Gg, and enhance manure recycling by 100 Gg. This strategy would yield a 24% reduction in nitrogen losses, a 9% increase in livestock production, and a 40% rise in manure recycling in smaller-size farming regions, highlighting the critical role of livestock farm size in achieving significant environmental and food security benefits. • Livestock NUE rises and N loss intensity decreases with farm size. • Manure recycling ratios vary with farm size across different livestock types. • Optimizing farm size for 16% of intensive farms could reduce N losses by 1.2 Tg. • Farm size optimization improves societal and environment benefits.
Benefits of CO2Fertilization on Global Grassland Nitrogen Cycles Miao Zheng, Jinglan Cui, Xiaoxi Wang, Xiuming Zhang, Stefan Reis, Shu Kee Lam, Sitong Wang, Jianming Xu, Baojing Gu Environmental Science and Technology, 2026 Grasslands are vital for providing wildlife habitats, essential ecosystem services, and food to humanity. Elevated atmospheric CO2 concentration (eCO2), as a key driver of climate change, has substantial effects on grasslands. Nonetheless, a holistic quantification on the response of the nitrogen cycle to eCO2 in global grasslands is lacking. Here, we show that solely eCO2 could increase the net primary productivity (NPP) in grasslands by 10% (95% confidence interval, 8–12%), yet simultaneously decrease leaf nitrogen content by 8% (95% confidence interval, 5–10%). When considering the effects of eCO2 on both NPP and leaf nitrogen content, we estimate a projected increase of 2.1 million tonnes per year (Tg yr–1) in nitrogen harvest by global grasslands under the eCO2 SSP2-4.5 scenario in 2050. The increase in nitrogen use efficiency by 29% (95% confidence interval, 18–40%) and biological nitrogen fixation by 66% (95% confidence interval, 18–138%) would lead to declines in nitrogen surplus (−28.3 Tg yr–1). These changes in the grassland nitrogen budget due to eCO2 would generate benefits to 158 billion US dollars by avoiding human and ecosystem health damages. Priority should be accorded to sustainable nitrogen management strategies to leverage the advantages of CO2 fertilization for ensuring food security and mitigating nitrogen pollution.
Aligning Nitrogen Form With Rice Preference Through Enhanced-Efficiency Fertilizers Raises Yield and Cuts Emissions Shending Chen, Chen Wang, Xiuming Zhang, Jinglan Cui, Jinbo Zhang, Christoph Müller, Zucong Cai, Baojing Gu Global Change Biology, 2026 Rice sustains nearly half of the global population, yet its nitrogen (N) use efficiency remains low, undermining both food security and environmental integrity. Rice predominantly absorbs ammonium (NH 4 + ), which is readily nitrified and lost through irrigation and drainage, posing a persistent management challenge. Integrating 1756 paired field observations and global modelling, we show that using enhanced‐efficiency fertilizers to maintain soil NH 4 + relative to conventional practices increases rice yield by 6%–10% and N use efficiency by 18%–33%, while reducing ammonia (NH 3 ) volatilization by 16%–50%, nitrous oxide (N 2 O) emissions by 25%–49%, and methane (CH 4 ) emissions by 9%–30%. This N transformation‐based management could reduce global N fertilizer inputs by 1.4 ± 0.06 million tonnes (Tg), generate an additional 72 ± 13 Tg of rice, and lower N 2 O, CH 4 , and NH 3 emissions by 0.07 ± 0.02, 6.8 ± 2.0, and 0.6 ± 0.2 Tg, respectively, equivalent to an annual reduction of about 202 Tg CO 2 ‐eq. The total social benefit is valued at US$51 ± 5 billion, including US$29 ± 2 billion in added food value, achieved with only US$1.6 ± 0.6 billion in fertilizer investment and US$0.9 ± 0.1 billion in transaction costs. Aligning N transformation processes with crop N preference thus represents a pivotal strategy for sustaining rice productivity while minimizing environmental impacts.
Asymmetry of safeguarding regional air and water nitrogen boundaries in China Yiyang Zou, Xiuming Zhang, Xin Xu, Jiami Wu, Luxi Cheng, Xinpeng Xu, Ouping Deng, Yuanyuan Chen, Chen Wang, Peiying He, Sitong Wang, Mengru Wang, Wilfried Winiwarter, Baojing Gu National Science Review, 2026 Human activities have significantly disrupted the global nitrogen cycle, positioning it as one of the most severely surpassed planetary boundaries. As the country with the largest nitrogen flux, China faces numerous environmental challenges due to excessive losses of reactive nitrogen (Nr) to both air and water from various sources. By quantifying the regional nitrogen boundaries for air and water at the county level, we found that the aggregated regional safe boundaries in China for the atmospheric release of Nr, nitrogen runoff to surface water and leaching to groundwater are 14.6, 5.2 and 4.8 million tonnes per year, respectively. In 2020, the cumulative Nr losses exceeded these boundaries by 54%, 262% and 258%, respectively. Implementing cross-system technical mitigation measures could potentially halve the total Nr losses to both air and water, yielding benefits that are ∼2.5 times greater than the net implementation costs. Despite most counties being capable of meeting the emission boundary for the atmospheric release of Nr after abatement, the boundaries for surface water and groundwater remain exceeded in over half of the counties. This highlights a significant asymmetry in nitrogen-pollution control between air and water, further necessitating socioeconomic transformations to effectively address the persistent issue of water pollution in China.
Cutting global nitrogen emissions by one-third for balanced and achievable SDGs by 2030 Yi Zhou, Xiuming Zhang, Yiyang Zou, Luxi Cheng, Xin Xu, Yuanyuan Chen, Jingfang Zhan, Haoyang Tu, Junjie Xu, Ouping Deng, Mahesh Pradhan, Joseph Gweyi-Onyango, Cargele Masso, Baojing Gu One Earth, 2026 Achieving the Sustainable Development Goals (SDGs) by 2030 is becoming difficult as global progress lags. Nitrogen is key to food security and environmental sustainability, making its management crucial for advancing multiple goals within the timeline. Here, we introduce an SDG-driven framework to evaluate nitrogen management under sustainable shared socioeconomic pathways. We show that meeting balanced and achievable targets, defined as an average nitrogen-related SDG index score above 75 with individual target scores exceeding 60, requires reducing global nitrogen emissions by 50 million tonnes (Tg) by 2030, 32% of 2020 levels, entailing decreases of 30 Tg in the atmosphere and 20 Tg in aquatic ecosystems. Existing technological strategies can deliver only half of the required mitigation, even with investments of $176 billion that yield economic benefits of $291 billion. This highlights that technologies alone are insufficient, and meaningful progress toward the SDGs depends on integrating mitigation techniques with broader socioeconomic transitions.
Halving global ammonia emissions with cost-effective measures Xiuming Zhang, Yi Sun, Yujing Gao, Chen Wang, Xia Liang, Shu Kee Lam, Shaohui Zhang, Wilfried Winiwarter, Hans J. M. van Grinsven, Mark A. Sutton, Deli Chen, Baojing Gu Nature Sustainability, 2026
Managing solid waste to co-control carbon and nitrogen leakage in China Xin Xu, Jingfang Zhan, Tianrun Chen, Xiuming Zhang, Yiyang Zou, Baojing Gu Resources Conservation and Recycling, 2026 Solid waste disposal generates substantial carbon and nitrogen leakage, adversely affecting air quality, aquatic ecosystems, and the climate. However, the coupled cycles of carbon and nitrogen within this sector remain insufficiently understood. This study develops an integrated carbon and nitrogen budget for China’s solid waste sector from 1980 to 2023. Over this period, atmospheric carbon emissions increased 3.6-fold, reaching 34.0 million tons (Tg) C yr -1 in 2023, while nitrogen losses peaked at 1.4 Tg N yr -1 in 2005 before declining. By 2060, an optimized co-control strategy could reduce carbon leakage by 87 % (30.2 Tg C yr -1 ) and nitrogen leakage by 96 % (0.9 Tg N yr -1 ), yielding net social benefits of US$34.6 billion. Source reduction strategies, particularly waste recovery programs and Pay-As-You-Throw tariffs, are the most cost-effective mitigation options. These findings underscore the critical role of solid waste management in promoting a circular economy and achieving sustainable development.
Managing urban development could halve nitrogen pollution in China Ouping Deng, Sitong Wang, Jiangyou Ran, Shuai Huang, Xiuming Zhang, Jiakun Duan, Lin Zhang, Yongqiu Xia, Stefan Reis, Jiayu Xu, Jianming Xu, Wim de Vries, Mark A. Sutton, Baojing Gu Nature Communications, 2024
Cost-effective mitigation of nitrogen pollution from global croplands Baojing Gu, Xiuming Zhang, Shu Kee Lam, Yingliang Yu, Hans J. M. van Grinsven, Shaohui Zhang, Xiaoxi Wang, Benjamin Leon Bodirsky, Sitong Wang, Jiakun Duan, Chenchen Ren, Lex Bouwman, Wim de Vries, Jianming Xu, Mark A. Sutton, Deli Chen Nature, 2023
Reactive nitrogen budgets in China Baojing Gu, Xiuming Zhang Atmospheric Reactive Nitrogen in China Emission Deposition and Environmental Impacts, 2019
Ammonia emissions may be substantially underestimated in China Xiuming Zhang, Yiyun Wu, Xuejun Liu, Stefan Reis, Jiaxin Jin, Ulrike Dragosits, Martin Van Damme, Lieven Clarisse, Simon Whitburn, Pierre-François Coheur, Baojing Gu Environmental Science and Technology, 2017
