Mycorrhizal Resilience in Quercus robur Following Prescribed Burning and Thinning.

* *Mycoremediation in Centuries-Old Quercus robur**: Investigating the Effects of Selective Thinning and Prescribed Burning on Arbuscular Mycorrhizal Fungal Community Composition and Function in Central Appalachian Mixed Hardwood Forest Stands

* *Abstract**

Arbuscular mycorrhizal (AM) fungi play a crucial role in regulating plant growth, nutrient cycling, and ecosystem resilience in mixed hardwood forest stands. Prescribed burning and selective thinning are common silvicultural practices used to promote forest regeneration and productivity. However, the impact of these practices on AM fungal community composition and function in mature Quercus robur trees is poorly understood. This study investigated the effects of prescribed burning and selective thinning on AM fungal community composition and function in Central Appalachian mixed hardwood forest stands. Our results show that prescribed burning and selective thinning significantly altered AM fungal community composition and function in mature Quercus robur trees. Specifically, we found that prescribed burning increased the abundance of Glomus intraradices and decreased the abundance of Scutellospora castanea. Additionally, selective thinning increased the allocation of sapwood to fine roots and decreased the allocation of sapwood to xylem. Our results suggest that prescribed burning and selective thinning can alter the AM fungal community and function in mature Quercus robur trees, potentially affecting forest resilience and productivity.

* *Introduction**

Mixed hardwood forest stands are characterized by a diverse mixture of tree species, including Quercus robur, which is a keystone species in Central Appalachian forests. Arbuscular mycorrhizal (AM) fungi play a crucial role in regulating plant growth, nutrient cycling, and ecosystem resilience in these forests. Prescribed burning and selective thinning are common silvicultural practices used to promote forest regeneration and productivity. However, the impact of these practices on AM fungal community composition and function in mature Quercus robur trees is poorly understood.

* *Methods**

We monumentalized 20 mature Quercus robur trees in a Central Appalachian mixed hardwood forest stand. Ten trees were subjected to prescribed burning, and the remaining ten trees were left unburned. Three trees from each treatment were subjected to selective thinning, and the remaining seven trees were left unthinned. We collected sapwood samples from each tree and analyzed them for AM fungal community composition and function using molecular and biochemical techniques.

* *Results**

Our results show that prescribed burning and selective thinning significantly altered AM fungal community composition and function in mature Quercus robur trees. Specifically, we found that prescribed burning increased the abundance of Glomus intraradices and decreased the abundance of Scutellospora castanea. Additionally, selective thinning increased the allocation of sapwood to fine roots and decreased the allocation of sapwood to xylem.

* *Discussion**

Our results suggest that prescribed burning and selective thinning can alter the AM fungal community and function in mature Quercus robur trees, potentially affecting forest resilience and productivity. The increased abundance of Glomus intraradices in response to prescribed burning may be due to the increased availability of nutrients in the soil. The decreased abundance of Scutellospora castanea in response to prescribed burning may be due to the increased competition for resources. The increased allocation of sapwood to fine roots in response to selective thinning may be due to the increased availability of resources.

* *Practical Implications**

Our results have practical implications for forest management. Prescribed burning and selective thinning can be used to promote forest regeneration and productivity, but they should be used with caution. The impact of these practices on AM fungal community composition and function should be carefully considered before implementation.

* *Limitations**

Our study had several limitations. We only investigated the effects of prescribed burning and selective thinning on AM fungal community composition and function in mature Quercus robur trees. We did not investigate the effects of these practices on other tree species or ecosystem processes.

* *Technical FAQ**

1. What is the effect of prescribed burning on AM fungal community composition and function in mature Quercus robur trees?

2. What is the effect of selective thinning on AM fungal community composition and function in mature Quercus robur trees?

3. How can prescribed burning and selective thinning be used to promote forest regeneration and productivity?

4. What are the limitations of this study?