Forest Diversity, Structure and Functions: Theories, Concepts and Analyses

Dear Colleagues,

Although species diversity is the principal component of (forest) stand structure, tree diameter diversity and height diversity, whether alone or together, are crown attributes which are typically considered to be stand structures. In forest ecosystems, it remains highly debated as to whether species diversity regulates forest functions such as aboveground biomass and productivity. This confusion is a result of the fact that divergent relationships (i.e., positive, negative or negligible) have been reported across the global forest ecosystems. As such, other metrics of species diversity, such as functional trait diversity, phylogenetic diversity and trait composition indices have, been put forward to explain forest functions across forest ecosystems worldwide. These relationships are usually linked to niche complementarity, mass ratio and selection effects in forests. However, the response of forest functions to soil, water and light can be dependent on the capture and use of the coexisting species in relation to their tree and crown sizes within a forest stand. Thus, in recent decades, a growing body of studies has come to suggest that stand structural attributes regulate forest functions better than species, functional and phylogenetic diversity, an occurrence which is probably due to the fact that differently sized trees have different, unique roles in the maintenance of biodiversity and forest functions.

It is also important to note that species diversity and stand structural attributes are not only the drivers of forest functions, but that they also respond to environmental and other coupling factors such as issue of climate, soil and disturbance. Some of the previous research has linked species diversity, stand structural attributes and forest functions to climate, soil and disturbance factors, but our understanding is limited to several forest ecosystems in the world or limited to a few common variables. Thus, further studies across ecosystems and biomes are needed to explore the effects of species diversity (including traits and phylogeny) and stand structural attributes on forest functions under the context of global change. This will require more informative factors, variables and indices as well as innovative research questions, hypotheses and conceptual models. For example, we must consider potential stand structural attributes based on tree diameter, height and crown dimensions, in addition to tree species diversity and composition (including traits and phylogeny), to explain forest functions, demographic processes, stability and services under global change drivers.

This Special Issue will serve as a platform to compile papers covering species diversity, stand structure and forest functions under the context of global change drivers such as climate, soil and disturbance factors. We encourage all types of submission, including both theoretical and experimental studies in natural forests and plantations, and the conceptual model must be tested with advanced statistical models such as structural equational models (SEMs) and multiple linear (mixed-effect) regression models.

We welcome discussions of the following subtopics:

• Environmental factors, anthropogenic disturbances, species diversity, stand structure and forest functions across forest strata;
• Effects of species diversity and stand structural complexity on aboveground and belowground forest functions under environmental changes;
• Linking tree crown attributes with species diversity and forest functions in a changing environment;
• Forest diversity, stand structure, and biomass dynamics under climate and soil conditions;
• Understanding forest multifunctionality in the context of stand structural complexity;
• Meta-analyses and reviews focusing on species diversity, stand structure and forest functions under global change.

Prof. Dr. Arshad Ali
Guest Editor

Manuscript Submission Information

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• aboveground biomass
• climate
• disturbance
• functional traits
• species diversity
• soil
• tree size