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[Objective] This study was aimed to reveal the spatio-temporal characteristics of supply-demand balance of ecosystem services, and further to explore the dual effects and influencing mechanisms of land use change on the supply-demand balance of ecosystem services. [Methods] Taking the middle reaches of the Yangtze River as the research area and seleting 2000— 2018 as the research period, the quantitative matrix of supply-demand of ecosystem services was employed to analyze the spatio-temporal characteristics of the supply-demand balance of ecosystem service, and the ecological contribution rate of land use change was introduced to analyze the influencing mechanisms of land use change on the supply-demand balance of ecosystem services. [Results] (1) During the study period, the supply-demand balance of ecosystem services in the middle reaches of the Yangtze River had been continuously deteriorating, which was mainly caused by the large-scale expansion of construction land and the large-scale reduction of cultivated land and forest land, resulting in the decrease of supply capacity and the increase of consumption demand of ecosystem services. (2) The relationship between different supply of ecosystem services had changed from trade-off to synergy in time scale, and the synergy between different demand and supply-demand balance of ecosystem services had been further enhanced on the time scale, but the trade-off or synergy between supply, demand, and supply-demand balance was highly heterogeneous on the spatial scale. (3) Land use change in the MRYR had dual effects on the supply-demand balance of ecosystem services, and the deterioration effect was significantly larger than the improvement effect, but the types of land use change that cause the improvement and deterioration of supply-demand of ecosystem services and their sub-services had temporal heterogeneity. [Conclusion] Promote types of land use change that could improve the supply-demand balance of ecosystem services; promote types of land use change that are compatible with key ecosystem services; and curb types of land use change that would worsen the supply-demand balance of ecosystem services, in order to increase the sustainability of ecosystem services and improve the quality of the ecological environment.

[Objective] From the perspective of socioeconomic development transition, this study aims to explores the spatiotemporal characteristics of land use change in the middle reaches of the Yangtze River (MRYR). [Methods] The method of change range and change speed of land use change, as well as geographical information map were employed. [Results] (1) The socioeconomic development stage of the MRYR have undergone two transition processes during 2000—2018. The first is from the primary production stage II to the middle industrialization stage, with slow growth of urbanization and serious outflow of population. The second is from the middle industrialization stage to the late industrialization stage, with steady growth of urbanization and continuous return of population. (2) In terms of overall characteristics, the cultivated land area continues to decrease, the water area and construction land area continue to increase, the woodland, grassland and wetland area obviously decrease, and the unused land area remains relatively stable. (3) In terms of process characteristics, in 2000—2010, cultivated land and forest land were transformed into each other, cultivated land into construction land and water area, and water area into wetland were the main change types. In 2010—2018, cultivated land and construction land were transformed into each other, forest land into construction land and cultivated land, and wetland into water area were the main change types. (4) In terms of trajectory characteristics, the early change type is the main type, followed by the late change type and repeated change type, and the proportion of continuous change type is small. [Conclusion] The stage characteristics of land use change in the MRYR are obvious, which is manifested in the change of land use quantitative and spatial structure caused by the scale and direction of transformation between different land use types in different transition periods of socioeconomic development.

The present continental crust is characterized by a felsic upper crust and a mafic lower crust, resulting from significant geochemical differentiation over geological time. While various processes have been proposed to explain this differentiation, subduction zones remain pivotal regions for understanding the compositional evolution of continental crust. This study focuses on the South Altyn (SA) continental subduction‐collision belt in western China, a unique setting that experienced ultra‐deep (>300 km) continental subduction followed by multi‐stage exhumation. We present a comprehensive study of four granitoid suites from Tatelekebulake (TTLK) area in SA: biotite granite (BG), monzogranite (MG), K‐feldspar granite (KG), and leucogranite (LG). Comprehensive studies on petrology, geochemistry and zircon U‐Pb dating show that these granitoids formed at 494, 451, 414, and 418 Ma, respectively, and originated from protoliths with affinity to the subducted continental crust in SA. Phase equilibrium modeling suggests that BG formed at ∼800°C and 0.6 GPa, while the MG, KG, and LG formed by differentiation crystallization of the BG magma under progressively decreasing temperature and pressure conditions (750°C, 0.5 GPa; 740–700°C, 0.2 GPa; and 700–640°C, 0.1 GPa, respectively). These results, combined with previous studies, allow us to reconstruct the tectonic processes of continental exhumation and subsequent orogenic collapse in SA during the Early Paleozoic. Importantly, our findings reveal that magmatism derived from partial melting of subducted continental crust can promote the geochemical evolution of continental crust toward more felsic compositions, even in the absence of significant crustal growth or mantle‐derived magmatism. This study provides a valuable case for understanding the compositional evolution of continental crust in deep subduction zones and challenges conventional models that rely heavily on arc magmatism for crustal differentiation. Moreover, our results contribute to a broader understanding of crustal evolution processes in collisional orogens worldwide and highlight the importance of recycling and differentiation of subducted continental material in shaping crustal compositions. Plain Language Summary: The geochemical evolution of the continental crust, from mafic composition 3 billion years ago to current composition stratified structure, is commonly believed to be driven by crustal growth through arc magmatism and undergoes a series of subsequent complex geodynamic processes. The study of the Early Paleozoic multi‐stage magmatism related to continental crust subduction and exhumation in the Tatelekebulake region of South Altyn western China reveals the differentiation, evolution and material cycling occurring in the absence of prominent arc magmatism mechanisms within the upper to middle crust range and provides a new scenario of the evolution of the continental crust, and crustal growth. This process could drive the upper continental crust toward a more felsic composition, while the middle to lower continental crust becomes more mafic characteristics. Key Points: The geochemistry characteristics of the four samples suggest derivation from the subducted continental crustThe study revealed multi‐stage magmatism associated with continental crust subduction and subsequent exhumationPartial melting of subducted continental crust can promote the geochemical evolution of continental crust toward more felsic compositions [ABSTRACT FROM AUTHOR]

Water dissolved in nominally anhydrous minerals (NAMs) can be transported to deep regions of the Earth through subducting slabs, thereby significantly influencing the physicochemical properties of deep-Earth materials and impacting dynamic processes in the deep Earth. Stishovite, a prominent mineral present in subducting slabs, remains stable at mantle pressures of 9–50 GPa and can incorporate various amounts of water (H + , OH - , and H 2 O) in its crystal structure. Consequently, stishovite can play a crucial role in transporting water into the deep Earth through subducting slabs. This paper provides a comprehensive review of the research process concerning water (hydrogen) solubility in stishovite. The key factors that govern water solubility in stishovite are summarized as temperature, pressure, water fugacity, and aluminum content. Combined with published results on the dependence of water solubility on the aforementioned parameters, this paper proposes a new equation to describe the solubility of water in Al-bearing stishovite. Calculation results based on this equation suggest that stishovite may effectively accommodate water released from processes such as hydrous mineral breakdown, which could ultimately contribute to the presence of a water-rich transition zone. [ABSTRACT FROM AUTHOR]

Aqueous zinc ion batteries are gaining popularity due to their high energy density and environmental friendliness. However, random deposition of zinc ions on the anode and sluggish migration of zinc ions on the interface would lead to the growth of zinc dendrites and poor cycling performance. To address these challenges, we developed a fluorinated solid‐state‐electrolyte interface layer composed of Ca5(PO4)3F/Zn3(PO4)2 via an in situ ion exchange strategy to guide zinc‐ion oriented deposition and fast zinc ion migration on the anode during cycling. The introduction of Ca5(PO4)3F (FAP) can increase the nucleation sites of zinc ions and guide the oriented deposition of zinc ions along the (002) crystal plane, while the in situ formation of Zn3(PO4)2 during cycling can accelerate the migration of zinc ions. Benefited from our design, the assembled Zn//V2O5 ⋅ H2O batteries based on FAP‐protected Zn anode (FAP‐Zn) achieve a higher capacity retention of 84 % (220 mAh g−1) than that of bare‐Zn based batteries, which have a capacity retention of 23 % (97 mAh g−1) at 3.0 A g−1 after 800 cycles. This work provides a new solution for the rational design and development of the solid‐state electrolyte interface layer to achieve high‐performance zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Water dissolved in nominally anhydrous minerals (NAMs) can be transported to deep regions of the Earth through subducting slabs, thereby significantly influencing the physicochemical properties of deep Earth materials and impacting dynamic processes in the deep Earth. Stishovite, a prominent mineral found in subducting slabs, remains stable at mantle conditions ranging from pressure of 9–50 GPa and can incorporate varying amounts of water (H+, OH−, and H2O) within its crystal structure. Consequently, stishovite plays a crucial role in transporting water into deep Earth through subducting slabs. This paper provides a comprehensive review of the research progress concerning water (hydrogen) solubility in stishovite. The key factors that govern water solubility in stishovite are summarized as temperature, pressure, water fugacity and aluminum content. Combined with published results on the dependence of water solubility on the aforementioned parameters, this paper proposes a new equation for water solubility in Al-bearing stishovite can be described by the relationship. Calculation results based on this equation suggest that stishovite may effectively absorb water released from processes such as hydrous mineral breakdown, dehydration reactions, and volume reduction, ultimately contributing to the presence of a water-rich transition zone. [ABSTRACT FROM AUTHOR]