Ongoing projects....
Wildfire
... and peatland resilience
With the prospect of
increasing temperatures at higher latitudes, wildfire frequency and severity in
forested boreal ecosystems are expected to increase. In combination with other
perturbations such as drainage, the boreal ecosystems may experience
more regime shifts; that is, when ecosystems are pushed into alternative states
which can have important implications for both boreal ecosystem structure and
function (e.g. water balance, biodiversity and carbon balance).
... ecosystem development
The boreal landscape changes fundamentaly when a fire occurs, but what determines the development post-fire? I am investigating how carbon and nitrogen accumualtion varies spatially and temporally post-fire and the interplay between abiotic and biotic factors. Here I want to link processes involved in plant community composition and link this to ecosystem processes at multiple scales. The goal is to develop models that predict post-fire development of ecosystem processes, including the aggregation of biodiversity in space and time.
In addition, I want to explore how today's management of pre-scribed burning affect processes and biodiversity in the landscape. We still know relatively little how this practice should be performed to achieve the set goal.
... ecosystem development
The boreal landscape changes fundamentaly when a fire occurs, but what determines the development post-fire? I am investigating how carbon and nitrogen accumualtion varies spatially and temporally post-fire and the interplay between abiotic and biotic factors. Here I want to link processes involved in plant community composition and link this to ecosystem processes at multiple scales. The goal is to develop models that predict post-fire development of ecosystem processes, including the aggregation of biodiversity in space and time.
In addition, I want to explore how today's management of pre-scribed burning affect processes and biodiversity in the landscape. We still know relatively little how this practice should be performed to achieve the set goal.
Global Sphagnum Production
We know, surprisingly,
rather little about global patterns of Sphagnum production and the influence of
environmental variables. There have been two major attempts to model Sphagnum
production on a global scale (Gunnarsson 2005, Loisel et al. 2012). These
publications, however, are based on data collected from the literature, based
on different methods, with limited spatial cover, over a long time period and
with no estimation of variability.
The idea with this project
is to measure Sphagnum production along major gradients of climate and N
deposition, by engaging peatland reserachers around the world. We focus on two
species, S. fuscum and S. magellanicum. These species have a wide distribution
and are of large ecological importance.
Eutrophication of forests and peatlands
Deposition of reactive nitrogen (N) has increased rapidly since the industrial revolution and consists of wet deposition (mainly NH4+,NO3-) and dry deposition (mainly NH3). In addition, fertilizers (mainly N) is sometimes used to enhance forest production Sweden. Because terrestrial ecosystems are mainly N limited, increased N input generally increases biomass production. However, in nutrient poor ecosystems, high N input can have severe negative effects on species diversity (e.g. competitive exclusion of slow growing plants) and ecosystem functions (e.g. microbial composition and C accumulation).
... effects of N application on boreal forests
Here we take advantage of a country wide fertilization and thinning experiments that has been running for over 40 years. We are looking at the impact of these treatments on biodiversity, berry production and carbon storage.
Peatlands are partparticularly poor habitats and therefore expected to be vulnerable to increased N input. In my work, I have
investigated the underlying mechanisms causing changes in Sphagnum production
under high N input. In addition, I have with Juul Limpens summarized the
experimental work on N effects on Sphagnum growth in three meta-analyses. However, the picture is still incomplete and additional work is needed.
