It is never an easy task for China to feed 1.4 billion people with only 7%of the world's arable land.With nearly 30%of the world's nitrogen(N)fertilizer applied,China achieves high crop yields while facing N p...It is never an easy task for China to feed 1.4 billion people with only 7%of the world's arable land.With nearly 30%of the world's nitrogen(N)fertilizer applied,China achieves high crop yields while facing N pollution result-ing from excessive N input.Here,we calculate the farmland N budget on the national and regional scales.The N use efficiency(NUE)in China increased by 28.0%during 2005-2018.This improvement is due to the reduction in fertilization and the improvement of crop management.The fragmented farmland is changing to large-scale farmland with the increase in cultivated land area per rural population and the development of agricultural mech-anization.This opportunity brings more possibilities for precision farmland management,thus further improving NUE.The goal of an NUE of 0.6 may be achieved in the 2040s based on the current development trend.This striking N use shift in China has important implications for other developing countries.展开更多
Fungi are known to be crucial in the formation and stabilization of soil organic matter through their exudates and dead residues(necromass).Yet,it remains unclear how fungi contribute to the persistence of carbon in s...Fungi are known to be crucial in the formation and stabilization of soil organic matter through their exudates and dead residues(necromass).Yet,it remains unclear how fungi contribute to the persistence of carbon in soils over millennial scales across biomes.Here,this study fills the knowledge gap by linking fungal carbon stocks with minerals-associated carbon stocks across major biomes.A strong correlation between fungal biomass and reactive mineral-associated carbon stocks in soils across six biomes supports the substantial role of fungi in soil carbon persistence at the global level.High spatial resolution nanoscale secondary ion mass spectrometry revealed that fungi may stabilize carbon by forming organo-mineral associations through their close physical connection to reactive minerals and weathered nanoparticles.We propose a conceptual model that emphasizes the dualistic role of hypha-mineral interactions:(i)fungi accelerate organic matter decomposition by producing reactive oxygen species on the hypha-mineral interfaces,and(ii)fungi stabilize their residues on mineral surfaces,leading to millennial scale persistence of soil C.Concluding,fungi play a fundamental role in ecosystems that extends beyond the decomposition of persistent carbon.They are crucial in stabilizing carbon on mineral surfaces,thereby facilitating the long-term removal of carbon from rapid biotic cycling.展开更多
Although pyrite is the main sedimentary form of sulfur,an ample mechanistic comprehension of its formation in low-sulfate environments is lacking.Applying high depth-resolution multigeochemical and stable sulfur isoto...Although pyrite is the main sedimentary form of sulfur,an ample mechanistic comprehension of its formation in low-sulfate environments is lacking.Applying high depth-resolution multigeochemical and stable sulfur isotope composition(δ34S)analysis of a sediment core recovered from a large shallow freshwater lake(Baiyangdian)in north China,we show that the pyrite forms dominantly in the top 4 cm layer and the participating sulfide stems primarily from mineralization of reduced organic sulfur in biomass.This mechanism was further verified by the formation of pyrite in anoxic incubation of biomass(Ceratophyllum demersum L.or Spirulina)with hematite in the absence of external sulfate.This finding reveals an alternative pathway other than microbial sulfate reduction(MSR)for producing sulfide to form pyrite in low-sulfate sediments.展开更多
基金supported by the National Natural Science Foun-dation of China(Grants No.U21A2025 and 41907151)the National Key Research and Development Program of China(Grant No.2022YFD1700700).
文摘It is never an easy task for China to feed 1.4 billion people with only 7%of the world's arable land.With nearly 30%of the world's nitrogen(N)fertilizer applied,China achieves high crop yields while facing N pollution result-ing from excessive N input.Here,we calculate the farmland N budget on the national and regional scales.The N use efficiency(NUE)in China increased by 28.0%during 2005-2018.This improvement is due to the reduction in fertilization and the improvement of crop management.The fragmented farmland is changing to large-scale farmland with the increase in cultivated land area per rural population and the development of agricultural mech-anization.This opportunity brings more possibilities for precision farmland management,thus further improving NUE.The goal of an NUE of 0.6 may be achieved in the 2040s based on the current development trend.This striking N use shift in China has important implications for other developing countries.
基金the support by the RUDN University Strategic Academic Leadership Programinfrastructural support by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany's Excellence Strategy,cluster of Excellence EXC2124,project ID 390838134+1 种基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20608,42293264&41977271)Tianjin Municipal Science and Technology Bureau(Grant Nos.23ZYJDJC00050&24ZYJDJC00330)。
文摘Fungi are known to be crucial in the formation and stabilization of soil organic matter through their exudates and dead residues(necromass).Yet,it remains unclear how fungi contribute to the persistence of carbon in soils over millennial scales across biomes.Here,this study fills the knowledge gap by linking fungal carbon stocks with minerals-associated carbon stocks across major biomes.A strong correlation between fungal biomass and reactive mineral-associated carbon stocks in soils across six biomes supports the substantial role of fungi in soil carbon persistence at the global level.High spatial resolution nanoscale secondary ion mass spectrometry revealed that fungi may stabilize carbon by forming organo-mineral associations through their close physical connection to reactive minerals and weathered nanoparticles.We propose a conceptual model that emphasizes the dualistic role of hypha-mineral interactions:(i)fungi accelerate organic matter decomposition by producing reactive oxygen species on the hypha-mineral interfaces,and(ii)fungi stabilize their residues on mineral surfaces,leading to millennial scale persistence of soil C.Concluding,fungi play a fundamental role in ecosystems that extends beyond the decomposition of persistent carbon.They are crucial in stabilizing carbon on mineral surfaces,thereby facilitating the long-term removal of carbon from rapid biotic cycling.
基金supported by the National Natural Science Foundation of China(41991331 and 21920102002)the National Key Research and Development Program of China(2019YFC1804202).
文摘Although pyrite is the main sedimentary form of sulfur,an ample mechanistic comprehension of its formation in low-sulfate environments is lacking.Applying high depth-resolution multigeochemical and stable sulfur isotope composition(δ34S)analysis of a sediment core recovered from a large shallow freshwater lake(Baiyangdian)in north China,we show that the pyrite forms dominantly in the top 4 cm layer and the participating sulfide stems primarily from mineralization of reduced organic sulfur in biomass.This mechanism was further verified by the formation of pyrite in anoxic incubation of biomass(Ceratophyllum demersum L.or Spirulina)with hematite in the absence of external sulfate.This finding reveals an alternative pathway other than microbial sulfate reduction(MSR)for producing sulfide to form pyrite in low-sulfate sediments.
