Background/Question/Methods Oak decline has impacted Midwestern-upland oak-hickory forests, parti... more Background/Question/Methods Oak decline has impacted Midwestern-upland oak-hickory forests, particularly species in the red oak group (Quercus Section Lobatae) across the Ozark Highlands of Missouri, Arkansas and Oklahoma. Drought is a common inciting factor in oak decline, while advanced tree age is considered a predisposing factor, and opportunistic organisms such as armillaria root fungi and opportunistic insects are believed to contribute to oak decline. Declining trees are initially indicated by foliage wilt and browning followed by progressive branch dieback. If crown dieback continues trees can die. The objective of this study was to analyze oak mortality by species group and inventory year to illustrate the general spatial and temporal trends of oak decline and mortality by using the 1999-2010 Forest Inventory and Analysis (FIA) annualized data from plots in the Ozark Highlands of Arkansas and Missouri landscape. Results/Conclusions Of the species groups examined in this stu...
Temperate forests regrowing from historical land use and land cover change in the eastern US serv... more Temperate forests regrowing from historical land use and land cover change in the eastern US serve as carbon (C) sinks. Environmental drivers have been significantly altered (e.g. rising atmospheric CO2concentration, warmer temperature, and elevated nitrogen (N) deposition) and will have a wide range of impacts on future forest C sinks. However, the interactions among these environmental drivers are unclear and their effects are subject to uncertainty. We assessed the combined and interactive effects of rising CO2concentration, climate change (temperature, precipitation), and N deposition on forest aboveground net primary production (ANPP) and their relative contribution to ANPP changes of a temperate forest in the eastern US. We used a process-based ecosystem model PnET-day to simulate coupled cycles of C, water, and N of forest ecosystems. We found that (1) climate change exerted negative effects on ANPP (−0.250 kg C m−2yr−1) whereas rising CO2and N deposition enhanced ANPP (+0.25...
Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate suc... more Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of succession and harvest and may not consider important species‐specific demographic processes driving forests changes. We determined the relative importance of succession, harvest, and climate change to forest composition changes in a 125‐million ha area of the Central Hardwood Forest Region of U.S. We used a forest landscape modeling approach to project changes in density and basal area of 23 tree species due to succession, harvest, and four climate scenarios from 2000 to 2300. On average, succession, harvest, and climate change explained 78, 17, and 1% of the variation in species importance values (IV) at 2050, respective...
Background/Question/Methods Oak decline has impacted Midwestern-upland oak-hickory forests, parti... more Background/Question/Methods Oak decline has impacted Midwestern-upland oak-hickory forests, particularly species in the red oak group (Quercus Section Lobatae) across the Ozark Highlands of Missouri, Arkansas and Oklahoma. Drought is a common inciting factor in oak decline, while advanced tree age is considered a predisposing factor, and opportunistic organisms such as armillaria root fungi and opportunistic insects are believed to contribute to oak decline. Declining trees are initially indicated by foliage wilt and browning followed by progressive branch dieback. If crown dieback continues trees can die. The objective of this study was to analyze oak mortality by species group and inventory year to illustrate the general spatial and temporal trends of oak decline and mortality by using the 1999-2010 Forest Inventory and Analysis (FIA) annualized data from plots in the Ozark Highlands of Arkansas and Missouri landscape. Results/Conclusions Of the species groups examined in this stu...
Temperate forests regrowing from historical land use and land cover change in the eastern US serv... more Temperate forests regrowing from historical land use and land cover change in the eastern US serve as carbon (C) sinks. Environmental drivers have been significantly altered (e.g. rising atmospheric CO2concentration, warmer temperature, and elevated nitrogen (N) deposition) and will have a wide range of impacts on future forest C sinks. However, the interactions among these environmental drivers are unclear and their effects are subject to uncertainty. We assessed the combined and interactive effects of rising CO2concentration, climate change (temperature, precipitation), and N deposition on forest aboveground net primary production (ANPP) and their relative contribution to ANPP changes of a temperate forest in the eastern US. We used a process-based ecosystem model PnET-day to simulate coupled cycles of C, water, and N of forest ecosystems. We found that (1) climate change exerted negative effects on ANPP (−0.250 kg C m−2yr−1) whereas rising CO2and N deposition enhanced ANPP (+0.25...
Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate suc... more Most temperate forests in U.S. are recovering from heavy exploitation and are in intermediate successional stages where partial tree harvest is the primary disturbance. Changes in regional forest composition in response to climate change are often predicted for plant functional types using biophysical process models. These models usually simplify the simulation of succession and harvest and may not consider important species‐specific demographic processes driving forests changes. We determined the relative importance of succession, harvest, and climate change to forest composition changes in a 125‐million ha area of the Central Hardwood Forest Region of U.S. We used a forest landscape modeling approach to project changes in density and basal area of 23 tree species due to succession, harvest, and four climate scenarios from 2000 to 2300. On average, succession, harvest, and climate change explained 78, 17, and 1% of the variation in species importance values (IV) at 2050, respective...
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Papers by Hong S. He