台风干扰海岸林受损及灾后恢复的影响因素研究进展OACHSSCDCSTPCD

Typhoon intensity and frequency increase with global climate warming,heavily affect the coastal forest,and pose a high risk on the ecological security in coastal areas.Currently,some uncertainties remain in the study of coastal forest after typhoon disturbance,particularly in the affecting factors attributed to the damage levels and recovery intervals of trees,due to the uncertainty of typhoon landfall,lagging recovery of coastal forest,and shortage of available data sources.The damage levels of coastal forest can be mainly classified as defoliation,tree snapping and uprooting after typhoon disturbance,which usually show high heterogeneities at different spatial scales,and cannot be completely explained by any one of the factors.These factors include the variations of species characteristics(canopy,stem and root),stand structures(density and composition),site conditions(landform and soil),and typhoon characteristics(intensity and frequency).Specifically,tall trees usually indicate high canopy damages,but their widespread roots decrease the uprooting ratio after typhoon disturbance.Sparse or dense stand structures increase tree damages,and a high biodiversity does not always guarantee a low damage level of coastal forest.The damage levels of coastal forest do not show consistent trends with the variations of elevations,aspects and slope angels.Moreover,coarse soil can facilitate the water infiltration,and enhance the growth of deep root,but often has a lower fixation on the trees,vice versa.The increase of typhoon intensity aggravate,but the increase of typhoon frequency can alleviate the damage levels of coastal forest.A few coastal forests will die after typhoon disturbance due to the heavy damage level,while the rest of which can regenerate by seed germination,seedling/sapling growth and sprouting.The recovery intervals usually vary from several months to decades,which are largely dependent on the regeneration strategies(seedling and coppice),forest types(plantation and natural forest),damage levels(slight and heavy),and hydrothermal conditions(water and heat).Specifically,coppice,natural forest,slightly damaged trees grown in the excellent hydrothermal conditions usually have more shorter recovery intervals.Therefore,multiple-source remote sensing datasets,long-term field observations,combined with field monitoring,sampling and sample analysis in laboratories should be used to investigate the damage and restoration patterns of the coastal forest at multiple spatio-temporal scales,and to analyze the water transport and carbohydrates allocation process of trees in different damage levels after typhoon disturbance,which will facilitate the explanation on the affecting mechanism of coastal forest disturbed by typhoon.