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China has become the largest consumer of chemical fertilizers. The excessive application of chemical fertilizers has resulted in a series of problems including environmental pollution, seriously threatening China’s sustainable development. Therefore, it is highly important to study the factors driving chemical fertilizer consumption. In this study, we used the panel data of 31 provinces in China and the Tapio decoupling model to explore the coupling relationship between fertilizer consumption, economic growth and crop yield increase, build the IPAT-LMDI model, and identify and analyze the factors driving the observed changes. The results show the following: (1) Since 2015, the consumption of chemical fertilizers in most provinces of China has decreased significantly, and the implementation of the zero-fertilizer policy in various regions has generally achieved remarkable results. (2) Since 1980, China’s crop production and economic development have undergone coordinated growth, but the decoupling relationship between chemical fertilizer consumption and economic growth has changed from weak to strong, and the dependence of China’s crop production on chemical fertilizers has gradually been reduced. (3) Fertilizer consumption in China is promoted by factors related to economic level (Pg), crop value (Cval), fertilizer efficiency (Feff), fertilization intensity (Fein), per capita arable land area (Clap) and population size (P), while it is restrained by factors related to science and technology level (Ffag), agricultural population (P1) and industrial structure (Inst). (4) Fertilizer consumption has arrived at its peak in East China, South China and Central China, while there is still room for growth in the western areas; gaps in economic and technological development between different provinces are the main factors affecting changes in fertilizer consumption. Finally, we offer specific suggestions for improving the efficiency of chemical fertilizers from the perspectives of farming modes and science and technology. Full article

EXAFS spectroscopy is one of the most used techniques to solve the structure of actinoid solutions. In this work a systematic analysis of the EXAFS spectra of four actinyl cations, [UO₂]²⁺, [NpO₂]²⁺, [NpO₂]⁺ and [PuO₂]²⁺ has been carried out by comparing experimental results with theoretical spectra. These were obtained by averaging individual contributions from snapshots taken from classical Molecular Dynamics simulations which employed a recently developed [AnO₂]^2+/+ –H₂O force field based on the hydrated ion model using a quantum-mechanical (B3LYP) potential energy surface. Analysis of the complex EXAFS signal shows that both An-O${}_{\mathrm{yl}}$ and An-O${}_{\mathrm{W}}$ single scattering paths as well as multiple scattering ones involving [AnO₂]^+/2+ molecular cation and first-shell water molecules are mixed up all together to produce a very complex signal. Simulated EXAFS from the B3LYP force field are in reasonable agreement for some of the cases studied, although the k= 6–8 Å${}^{-1}$ region is hard to be reproduced theoretically. Except uranyl, all studied actinyls are open-shell electron configurations, therefore it has been investigated how simulated EXAFS spectra are affected by minute changes of An-O bond distances produced by the inclusion of static and dynamic electron correlation in the quantum mechanical calculations. A [NpO₂]⁺−H₂O force field based on a NEVPT2 potential energy surface has been developed. The small structural changes incorporated by the electron correlation on the actinyl aqua ion geometry, typically smaller than 0.07 Å, leads to improve the simulated spectrum with respect to that obtained from the B3LYP force field. For the other open-shell actinyls, [NpO₂]²⁺ and [PuO₂]²⁺, a simplified strategy has been adopted to improve the simulated EXAFS spectrum. It is computed taking as reference structure the NEVPT2 optimized geometry and including the DW factors of their corresponding MD simulations employing the B3LYP force field. A better agreement between the experimental and the simulated EXAFS spectra is found, confirming the a priori guess that the inclusion of dynamic and static correlation refine the structural description of the open-shell actinyl aqua ions. Full article