Periodic Reporting for period 1 - BIOCOMP (Consequences of global biodiversity loss and climate change for decomposer communities and implications for forest carbon fluxes)
Okres sprawozdawczy: 2023-05-01 do 2025-10-31
Ecosystems worldwide undergo rapid reorganization driven primarily by anthropogenic processes, such as land use and climate change. As a result, biodiversity is declining and ecosystem functioning is altered,
either directly or indirectly as a result of biodiversity change. Forests host a large share of all terrestrial taxa on Earth and they play a key role in global carbon cycles. Here, decomposition of organic matter such as deadwood is an important ecosystem process which is driven by a complex interaction of climatic factors and decomposer biodiversity. To make a projection of the future of forest biodiversity and the global forest carbon sink, a better understanding is needed how forest use and climate interactively affect decomposer biodiversity and carbon release from wood decomposition. To close this knowledge gap, BIOCOMP is using a combination of complementary methodological approaches operating at different spatial scales. To measure the effects of forest use and climate on biodiversity and decomposition rates, a distributed experiment has been established which represent the major climate zones. Each site contains two plots which represent a contrast in forest use (natural vs. anthropogenic). At these sites, biodiversity of arthropods as well as of fungi and bacteria in deadwood and soil are assessed and wood decomposition rates are measured. For this, experiments with fresh deadwood were implemented which allow to separate the contribution of different functional groups of decomposers to wood decomposition. In addition, further experiments are conducted in the field and in climate chambers to study the mechanisms underlying global patterns.
The BIOCOMP project generates a better understanding of the global drivers of decomposer biodiversity and decomposition processes and as such, provide the scientific basis for developing a new generation of climate and forest policies that consider the intimate connections between climate change, land use and biodiversity.
either directly or indirectly as a result of biodiversity change. Forests host a large share of all terrestrial taxa on Earth and they play a key role in global carbon cycles. Here, decomposition of organic matter such as deadwood is an important ecosystem process which is driven by a complex interaction of climatic factors and decomposer biodiversity. To make a projection of the future of forest biodiversity and the global forest carbon sink, a better understanding is needed how forest use and climate interactively affect decomposer biodiversity and carbon release from wood decomposition. To close this knowledge gap, BIOCOMP is using a combination of complementary methodological approaches operating at different spatial scales. To measure the effects of forest use and climate on biodiversity and decomposition rates, a distributed experiment has been established which represent the major climate zones. Each site contains two plots which represent a contrast in forest use (natural vs. anthropogenic). At these sites, biodiversity of arthropods as well as of fungi and bacteria in deadwood and soil are assessed and wood decomposition rates are measured. For this, experiments with fresh deadwood were implemented which allow to separate the contribution of different functional groups of decomposers to wood decomposition. In addition, further experiments are conducted in the field and in climate chambers to study the mechanisms underlying global patterns.
The BIOCOMP project generates a better understanding of the global drivers of decomposer biodiversity and decomposition processes and as such, provide the scientific basis for developing a new generation of climate and forest policies that consider the intimate connections between climate change, land use and biodiversity.
A global network of 48 sites across six continents has been established including two plots per site representing a contrast in forest use. At each plot, different trap types are used to sample arthropods and deadwood and soil samples are collected to sample fungi and bacteria. Metabarcoding is used to identify species from these samples. To measure wood decomposition rates and the contribution of different functional groups of decomposers, fresh deadwood logs of four local species and of one standard wood type are exposed under different treatments excluding either soil-borne, air-borne or all arthropods. Microclimate is measured using in-situ loggers and forest structural characteristics are assess based on forest and deadwood inventories.
In addition, a mechanistic experiment testing if the interaction between insects and fungi – the two major decomposer groups – differ between climate zones has been designed. It includes treatments that isolate fungal colonization processes into soil-borne, air-borne and insect-mediated. This experiment has been implemented in temperate forest in Germany and will be expanded to a Mediterranean, a boreal and a subtropical site.
In addition, a mechanistic experiment testing if the interaction between insects and fungi – the two major decomposer groups – differ between climate zones has been designed. It includes treatments that isolate fungal colonization processes into soil-borne, air-borne and insect-mediated. This experiment has been implemented in temperate forest in Germany and will be expanded to a Mediterranean, a boreal and a subtropical site.
Preliminary results from a subset of sites show clear patterns of arthropod, fungal and bacterial communities along climatic gradients, but also strong contrasts between natural and anthropogenic forests.