Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories es...Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories estimate forest characteristics for grid cell areas(pixels),which are then usually summarized at the stand level.Using the ALS-based high-resolution Norwegian Forest Resource Maps(16 m×16 m pixel resolution)alongside with stand-level growth and yield models,this study explores the impact of three levels of pixel aggregation(standlevel,stand-level with species strata,and pixel-level)on projected stand development.The results indicate significant differences in the projected outputs based on the aggregation level.Notably,the most substantial difference in estimated volume occurred between stand-level and pixel-level aggregation,ranging from-301 to+253 m^(3)·ha^(-1)for single stands.The differences were,on average,higher for broadleaves than for spruce and pine dominated stands,and for mixed stands and stands with higher variability than for pure and homogenous stands.In conclusion,this research underscores the critical role of input data resolution in forest planning and management,emphasizing the need for improved data collection practices to ensure sustainable forest management.展开更多
Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate warming.Knowledge of tree growth declines will help anticipate future respo...Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate warming.Knowledge of tree growth declines will help anticipate future responses of forests to climate change.In this study,we investigated tree growth declines over the last four centuries in a juniper forest on the eastern Tibetan Plateau.By analyzing the radial growth trajectories of individual trees,we identified two events of intense growth decline,one in 1817–1830 and the other in 1969–1999 over the past four centuries.The intensity of the recent decline was unprecedented in the period under study.Ring-width chronology showed a positive correlation with self-calibrating Palmer Drought Severity Indices and a negative correlation with mean monthly temperatures in May and June.The recent intensified growth decline may have been due to temperatureinduced frequent droughts in the study area.Our findings suggest that trees in this juniper forest may face a higher risk of growth decline and even mortality under continued climate warming.展开更多
文摘Forest management planning often relies on Airborne Laser Scanning(ALS)-based Forest Management Inventories(FMIs)for sustainable and efficient decision-making.Employing the area-based(ABA)approach,these inventories estimate forest characteristics for grid cell areas(pixels),which are then usually summarized at the stand level.Using the ALS-based high-resolution Norwegian Forest Resource Maps(16 m×16 m pixel resolution)alongside with stand-level growth and yield models,this study explores the impact of three levels of pixel aggregation(standlevel,stand-level with species strata,and pixel-level)on projected stand development.The results indicate significant differences in the projected outputs based on the aggregation level.Notably,the most substantial difference in estimated volume occurred between stand-level and pixel-level aggregation,ranging from-301 to+253 m^(3)·ha^(-1)for single stands.The differences were,on average,higher for broadleaves than for spruce and pine dominated stands,and for mixed stands and stands with higher variability than for pure and homogenous stands.In conclusion,this research underscores the critical role of input data resolution in forest planning and management,emphasizing the need for improved data collection practices to ensure sustainable forest management.
基金financially supported by the National Natural Science Foundation of China project(No.31330015)
文摘Forest structure and function are subject to risks of growth declines from intensified drought and frequent extreme events related to climate warming.Knowledge of tree growth declines will help anticipate future responses of forests to climate change.In this study,we investigated tree growth declines over the last four centuries in a juniper forest on the eastern Tibetan Plateau.By analyzing the radial growth trajectories of individual trees,we identified two events of intense growth decline,one in 1817–1830 and the other in 1969–1999 over the past four centuries.The intensity of the recent decline was unprecedented in the period under study.Ring-width chronology showed a positive correlation with self-calibrating Palmer Drought Severity Indices and a negative correlation with mean monthly temperatures in May and June.The recent intensified growth decline may have been due to temperatureinduced frequent droughts in the study area.Our findings suggest that trees in this juniper forest may face a higher risk of growth decline and even mortality under continued climate warming.
