Low-Hanging DendroDynamic Fruits Regarding Disturbance in Temperate, Mesic Forests

Abstract

Temperate, mesic forests (TMFs) are generally viewed as being in a shifting-mosaic or a kind of dynamic equilibrium at broad spatial scales. Gaining insight to the potential dynamics of TMFs at large-scales is crucial because these species-rich, highly productive forests are important drivers of regional water and carbon cycles for approximately one billion people. Here, we briefly review the disturbance dynamics of TMFs in eastern North America, Central Europe, and Japan, as well as the temperate rainforests of northwestern North America and western Eurasia. We find that current knowledge effectively describes the relatively frequent disturbance processes from stand to landscape scales. The few large-scale dendroecological networks in TMFs, however, suggest that large, infrequent disturbances (LIDs), those at regional scales or larger, are also important drivers of forest development. We also discuss the potential reasons why the spatiotemporal scales at which most ecological research is conducted—centennial-scale investigations (or longer) at small spatial scales or regional investigations (and larger) that only cover a few years to a decade or two— might bias our perception of TMF dynamics. Our review leads us to hypothesize that the dynamic equilibrium concept in TMFs could be challenged by findings derived from broad-scale networks containing centuries of forest dynamics at high temporal resolution. Dendroecology is poised for this challenge. We provide dendroecological solutions to test the hypothesis that LIDs are important for long-term TMF dynamics. Our review also leads us to assert that the successional trajectories in TMFs are likely more diverse than what is commonly considered. Constraining the potential number of trajectories likely constrains ecological theory and forest management. To expand these perceptions, we present a conceptual model to aid comprehension of the potential n-dimensional developmental trajectories in diverse TMFs. As we close in on a century of tree-ring research, new frontiers are being opened through the development of new methods and techniques that enhance investigations of temperate mesic forests. Applying these advances will help to address urgent questions on macroecological dynamics of temperate, mesic forests as climate change intensifies over the next century.