Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation...Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.展开更多
目的对比研究计算机辅助光学导航与电磁导航下精准牙种植手术的优缺点。方法 下颌牙列缺损拟行牙种植手术患者10例,采集患者颌骨CBCT影像,5例在计算机辅助光学导航下行牙种植手术,5例在计算机辅助电磁导航下行牙种植手术。术后拍摄CBCT...目的对比研究计算机辅助光学导航与电磁导航下精准牙种植手术的优缺点。方法 下颌牙列缺损拟行牙种植手术患者10例,采集患者颌骨CBCT影像,5例在计算机辅助光学导航下行牙种植手术,5例在计算机辅助电磁导航下行牙种植手术。术后拍摄CBCT进行种植位点评估。结果 两组患者均获得了良好的治疗效果,所有植体均植入理想的颌骨位置中。两组患者植体整体角度偏差范围不超过25°,植入深度偏差均不超过 1.4 mm;光学导航组植体植入角度偏差小于电磁导航组( t =3.5, P <0.05),两组患者植体植入深度差异无显著性( P >0.05)。结论 计算机辅助光学导航与电磁导航下均可完成精准牙种植手术,在应用过程中,两者各有优势和不足,电磁导航对于手术室环境要求较苛刻,在常规环境中精度略低于光学导航。在进一步研究中如果可以将光学导航和电磁导航相结合进行精准牙种植手术,将大大提高计算机辅助导航在牙种植领域的应用范围,特别是为复杂牙种植手术提供新的助力。展开更多
基金jointly supported by the National Natural Science Foundation of China(42361024,42101030,42261079,and 41961058)the Talent Project of Science and Technology in Inner Mongolia of China(NJYT22027 and NJYT23019)the Fundamental Research Funds for the Inner Mongolia Normal University,China(2022JBBJ014 and 2022JBQN093)。
文摘Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas.
文摘目的对比研究计算机辅助光学导航与电磁导航下精准牙种植手术的优缺点。方法 下颌牙列缺损拟行牙种植手术患者10例,采集患者颌骨CBCT影像,5例在计算机辅助光学导航下行牙种植手术,5例在计算机辅助电磁导航下行牙种植手术。术后拍摄CBCT进行种植位点评估。结果 两组患者均获得了良好的治疗效果,所有植体均植入理想的颌骨位置中。两组患者植体整体角度偏差范围不超过25°,植入深度偏差均不超过 1.4 mm;光学导航组植体植入角度偏差小于电磁导航组( t =3.5, P <0.05),两组患者植体植入深度差异无显著性( P >0.05)。结论 计算机辅助光学导航与电磁导航下均可完成精准牙种植手术,在应用过程中,两者各有优势和不足,电磁导航对于手术室环境要求较苛刻,在常规环境中精度略低于光学导航。在进一步研究中如果可以将光学导航和电磁导航相结合进行精准牙种植手术,将大大提高计算机辅助导航在牙种植领域的应用范围,特别是为复杂牙种植手术提供新的助力。
