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Through molecular dynamics simulations, this study investigates the orientation and temperature dependence of the tensile mechanical properties, the failure mechanism, and crack propagation characteristics of MgAl2O4 single crystal. The results reveal significant anisotropy and temperature sensitivity in the mechanical properties of MgAl2O4. Particularly, [111]-oriented MgAl2O4 exhibits the highest elastic modulus and ultimate tensile strength but a relatively minor failure strain. In the 300 K to 2100 K temperature range, the elastic modulus, ultimate tensile strength, and failure strain decrease with increasing temperature. At 2100 K, MgAl2O4 exhibits excellent structural stability and high-temperature strength. The failure mechanism is a brittle fracture initiated by the continuous convergence of vacancies into micropores/microcracks. The propagation of microcracks is influenced by crystal orientation and slip bands. Nevertheless, high temperatures significantly accelerate crack propagation, leading to premature failure. This study provides guidelines for preparing MgAl2O4 with excellent mechanical properties. [ABSTRACT FROM AUTHOR]

Habitat quality is a key expression of ecosystem ability and the basis for effective species conservation and regional ecological environment improvement. However, most studies have focused on assessing habitat quality over historical periods, ignoring the influence of coupled future development paths and climate change. The present study addresses this issue by developing a spatial‐temporal variation analysis framework for assessing habitat quality in China, which integrates the Integrated Valuation of Ecosystem Services and Trade‐offs (InVEST) model with eight Earth system coupled scenarios (SSP‐RCP). The results showed that from 2020 to 2100, and under five scenarios (SSP2‐4.5, SSP3‐7.0, SSP4‐6.0, SSP5‐3.4, and SSP5‐8.5), habitat quality was generally stable and high, while under three scenarios (SSP1‐1.9, SSP1‐2.6, and SSP4‐3.4), it decreased. The SSP2‐4.5 scenario was significantly better than the SSP4‐3.4 scenario. In all scenarios, the influences of different development patterns on China's ecologically fragile areas were obvious and serious. In 2030 and 2060, the spatial distribution patterns of habitat degradation and habitat quality had similar characteristics. High habitat degradation values were mostly distributed east of the Heihe‐Tengchong Line, while low values were mainly distributed in the arid zone. The mean habitat degradation ranged between 0.0226 and 0.0302, and the degradation degree was relatively light. The habitat quality index mean was 0.5120–0.5376, indicating that the overall habitat quality was at the medium level. This study provides a potential ecological protection baseline for China based on habitat protection and provides an important reference for China's sustainable development. Plain Language Summary: Habitat quality is a key expression of ecosystem ability and the basis for effective species conservation and regional ecological environment improvement. However, most studies have focused on assessing habitat quality over historical periods, ignoring the influence of coupled future development paths and climate change. The present study addresses this issue by developing a spatial‐temporal variation analysis framework for assessing habitat quality in China, which integrates the Integrated Valuation of Ecosystem Services and Trade‐offs (InVEST) model with eight Earth system coupled scenarios (SSP‐RCP). The results showed that from 2020 to 2100, and under five scenarios (SSP2‐4.5, SSP3‐7.0, SSP4‐6.0, SSP5‐3.4, and SSP5‐8.5), habitat quality was generally stable and high, while under three scenarios (SSP1‐1.9, SSP1‐2.6, and SSP4‐3.4), it decreased. The SSP2‐4.5 scenario was significantly better than the SSP4‐3.4 scenario. In all scenarios, the influences of different development patterns on China's ecologically fragile areas were obvious and serious. In 2030 and 2060, the spatial distribution patterns of habitat degradation and habitat quality had similar characteristics. High habitat degradation values were mostly distributed east of the Heihe‐Tengchong Line, while low values were mainly distributed in the arid zone. Key Points: We assess habitat quality in China under eight coupled scenarios of climate change and future development pathwaysThe overall habitat quality decreases under different scenarios from 2020 to 2100Climate change and different development patterns have the greatest impact on the ecologically fragile areas [ABSTRACT FROM AUTHOR]

Accurately assessing and predicting the impacts of land use changes on ecosystem carbon stocks in the Yellow River Basin (YRB) and exploring the optimization of land use structure to increase ecosystem carbon stocks are of great practical significance for China to achieve the goal of "double carbon". In this study, we used multi-year remote sensing data, meteorological data and statistical data to measure the ecosystem carbon stock in the YRB from 2000 to 2020 based on the InVEST model, and then simulated and measured the ecosystem carbon stock under four different land use scenarios coupled with the FLUS model in 2030. The results show that, from 2000 to 2020, urban expansion in the YRB continued, but woodland and grassland grew more slowly. Carbon stock showed an increasing trend during the first 20 years, with an overall increase of 7.2 megatons, or 0.23%. Simulating the four land use scenarios in 2030, carbon stock will decrease the most under the cropland protection scenario, with a decrease of 17.7 megatons compared with 2020. However, carbon stock increases the most under the ecological protection scenario, with a maximum increase of 9.1 megatons. Furthermore, distinct trends in carbon storage were observed across different regions, with significant increases in the upstream under the natural development scenario, in the midstream under the ecological protection scenario and in the downstream under the cropland protection scenario. We suggest that the upstream should maintain the existing development mode, with ecological protection prioritized in the middle reaches and farmland protection prioritized in the lower reaches. This study provides a scientific basis for the carbon balance, land use structure adjustment and land management decision-making in the YRB. [ABSTRACT FROM AUTHOR]