This study was conducted to analyze the variation of soil multifunctionality(SMF)along elevation and the driving factors in the Altun Shan.Soil samples(0–10 cm)were collected from 15 sites(H01 to H15)at every 200 m e...This study was conducted to analyze the variation of soil multifunctionality(SMF)along elevation and the driving factors in the Altun Shan.Soil samples(0–10 cm)were collected from 15 sites(H01 to H15)at every 200 m elevation interval,covering a total range from 900 m to 3500 m above mean sea level.We investigated climate factors(mean annual temperature,MAT;mean annual precipitation,MAP),soil environment(soil water content,electrical conductance,and pH),vegetation factors,and elevation to determine which of them are the main driving factors of the spatial variability of SMF in the Altun Shan.We explored the best-fit model of SMF along the changes in elevation using a structural equation model,performed variance partitioning analysis(VPA)on SMF with the“varpart”function to explain the relative contribution of various environmental factors to SMF changes,and used a random forest model for relative importance analysis.The results showed that SMF in the Altun Shan significantly increased with elevation in a linear trend.The main driver of changes in SMF was found to be MAP.Although the rise in elevation did not have a significant direct effect on changes in SMF,it could indirectly affect SMF by significantly influencing MAP,p H,MAT,and normalized difference vegetation index(NDVI).When considering climate,soil environment,and vegetation factors together,they explained 76%of the variation in SMF.The largest contribution to the variation in SMF was attributed to the independent effect of climate(0.31)and its interactive effect with soil(0.30).The relative importance of MAP on SMF changes was found to be the greatest.It is indicated that changes in SMF are caused by the combined effect of multiple environmental conditions.These findings are essential for understanding the spatial variability and drivers of SMF in dryland mountain ecosystems,especially concerning the function of mountain ecosystems in the context of global climatic changes.展开更多
采用电场辅助加热技术实现了Ti_3AlC_2/Zr的低温连接,并对其界面结构进行了研究。在TAC/Zr连接对中,Al的扩散激活能只有6.9 k J/mol,远低于传统的热压方法连接Ti_2AlC-Zr时Al的扩散激活能。TiC做过渡层时可以有效地抑制Al从Ti_3AlC_2一...采用电场辅助加热技术实现了Ti_3AlC_2/Zr的低温连接,并对其界面结构进行了研究。在TAC/Zr连接对中,Al的扩散激活能只有6.9 k J/mol,远低于传统的热压方法连接Ti_2AlC-Zr时Al的扩散激活能。TiC做过渡层时可以有效地抑制Al从Ti_3AlC_2一侧向Zr合金中扩散,并且可以进一步降低连接温度。研究发现,通过调控TiC涂层的计量比以调控连接界面的性能是完全有可能的。展开更多
基金the Tianshan Talent Plan(2022TSYCCX0001)Natural Science Foundation of Xinjiang(2022D01D083)+1 种基金the National Natural Science Foundation of China(U2003214 and 41977099)the Ecological Processes and Biological Adaptation team for financial and experimental instrumentation help。
文摘This study was conducted to analyze the variation of soil multifunctionality(SMF)along elevation and the driving factors in the Altun Shan.Soil samples(0–10 cm)were collected from 15 sites(H01 to H15)at every 200 m elevation interval,covering a total range from 900 m to 3500 m above mean sea level.We investigated climate factors(mean annual temperature,MAT;mean annual precipitation,MAP),soil environment(soil water content,electrical conductance,and pH),vegetation factors,and elevation to determine which of them are the main driving factors of the spatial variability of SMF in the Altun Shan.We explored the best-fit model of SMF along the changes in elevation using a structural equation model,performed variance partitioning analysis(VPA)on SMF with the“varpart”function to explain the relative contribution of various environmental factors to SMF changes,and used a random forest model for relative importance analysis.The results showed that SMF in the Altun Shan significantly increased with elevation in a linear trend.The main driver of changes in SMF was found to be MAP.Although the rise in elevation did not have a significant direct effect on changes in SMF,it could indirectly affect SMF by significantly influencing MAP,p H,MAT,and normalized difference vegetation index(NDVI).When considering climate,soil environment,and vegetation factors together,they explained 76%of the variation in SMF.The largest contribution to the variation in SMF was attributed to the independent effect of climate(0.31)and its interactive effect with soil(0.30).The relative importance of MAP on SMF changes was found to be the greatest.It is indicated that changes in SMF are caused by the combined effect of multiple environmental conditions.These findings are essential for understanding the spatial variability and drivers of SMF in dryland mountain ecosystems,especially concerning the function of mountain ecosystems in the context of global climatic changes.
文摘采用电场辅助加热技术实现了Ti_3AlC_2/Zr的低温连接,并对其界面结构进行了研究。在TAC/Zr连接对中,Al的扩散激活能只有6.9 k J/mol,远低于传统的热压方法连接Ti_2AlC-Zr时Al的扩散激活能。TiC做过渡层时可以有效地抑制Al从Ti_3AlC_2一侧向Zr合金中扩散,并且可以进一步降低连接温度。研究发现,通过调控TiC涂层的计量比以调控连接界面的性能是完全有可能的。
