I have held seminars for the biogeography module of the biogeosciences bachelor program and for the landscape ecology master program, where I have supervised individual student projects.

I have also been teaching about soil and land use for the Natural resources and sustainable development course (sustainable development program).

I have been involved as a teacher in the Tellus I (Physical Geography) and Tellus II (soil module) courses for several years.

My research focuses on soil ecology and biogeochemical cycles, and how these are influenced by climate and land-use change. Being a field scientist by training I am passionate about collecting data, and I have spent many hours digging in the dirt and pipetting in the lab.  

In my current project I try to disentangle the biotic and abiotic drivers of decomposition in forest soils by looking at the effects of soil moisture and temperature and of microbial diversity and community composition on soil CO2 fluxes under different managements. 

I enjoy working with modellers and the challenge of finding the most informative empirical data that might be used to improve model parametrizations, particularly related to C cycling. 

 

A selection from Stockholm University publication database

• Microbial biomass – not diversity – drives soil carbon and nitrogen mineralization in Spanish holm oak ecosystems

  2025. Elisa Bruni (et al.). Geoderma 460

  Article

  Soil microbial communities drive essential ecosystem functions, catalyzing biogeochemical cycles and contributing to climate regulation. However, due to the complexity of microbial communities, the magnitude and direction of microbial biomass and diversity contributions to carbon (C) and nutrient cycling remain unclear. For this reason, most models predicting soil organic matter (SOM) dynamics at the ecosystem level do not explicitly describe the role of microorganisms as mediators of SOM decomposition. Incorporating microbial properties, and especially diversity, into ecosystem models remains an open question, requiring careful consideration of the tradeoff between model complexity and performance.

  This work addresses this knowledge gap by implementing a simple C and nitrogen (N) cycling model to predict heterotrophic respiration and net N mineralization rates in soils sampled under different land-uses and tree health conditions across Spain. To understand the role of microorganisms on ecosystem functioning, we progressively incorporated microbial biomass and diversity (i.e., alpha diversity of taxa and of fungal functional groups), and selected the model that optimized prediction accuracy, while minimizing complexity.

  We found that microbial biomass had a strong and positive effect on both C and N mineralization rates, with heterotrophic respiration being nearly linearly controlled by biomass. In contrast, microbial diversity had minimal but negative effects on mineralization processes, with land-use differences explaining part of the variability in these effects. Our study confirms microbial biomass as a key driver of C and N mineralization rates, while highlights that microbial diversity based on taxonomic identification inadequately explains microbial effects on these ecosystem functions.

  Read more about Microbial biomass – not diversity – drives soil carbon and nitrogen mineralization in Spanish holm oak ecosystems

• Experimental drought and soil amendments affect grassland above- and belowground vegetation but not soil carbon stocks

  2025. Daniela Guasconi (et al.). SOIL 11 (1), 233-246

  Article

  Soils are the largest terrestrial carbon (C) pool on the planet, and targeted grassland management has the potential to increase grassland C sequestration. Appropriate land management strategies, such as organic matter addition, can increase soil C stocks and improve grasslands' resilience to drought by improving soil water retention and infiltration. However, soil carbon dynamics are closely tied to vegetation responses to management and climatic changes, which affect roots and shoots differently. This study presents findings from a 3-year field experiment on two Swedish grasslands that assessed the impact of compost amendment and experimental drought on plant biomass and soil C to a depth of 45 cm. Aboveground biomass and soil C content (% C) increased compared with untreated controls in compost-amended plots; however, because bulk density decreased, there was no significant effect on soil C stocks. Experimental drought did not significantly reduce plant biomass compared to control plots, but it stunted the increase in aboveground biomass in compost-treated plots and led to changes in root traits. These results highlight the complexity of ecosystem C dynamics and the importance of considering multiple biotic and abiotic factors across spatial scales when developing land management strategies to enhance C sequestration.

  Read more about Experimental drought and soil amendments affect grassland above- and belowground vegetation but not soil carbon stocks

• The hidden half of the meadow: Interactions between drought, soil carbon, roots and soil microbial communities

  2024. Daniela Guasconi.

  Thesis (Doc)

  Soil is a hidden ecosystem which harbours plant roots and countless microorganisms, vital for sustaining life aboveground. These belowground communities provide essential ecosystem services like soil stabilisation and organic matter decomposition. Soil is also one of the largest terrestrial carbon repositories, and land management strategies aimed at increasing organic matter inputs from plants, such as compost additions, can promote further soil carbon accumulation. Because organic carbon is important for soil water retention, this management may also help to increase resilience against more frequent and intense droughts. Although roots and microbial communities are largely acknowledged to play a key role in regulating the carbon cycle, there are still many open questions regarding the link between above- and belowground processes and ecosystem functions. Observing climate- and management-driven changes in the soil habitat is fundamental for understanding how ecosystems respond to environmental change.

  The aim of this thesis is to explore the relationship between soil properties, plant communities, and soil microbial communities in response to environmental changes. The research builds on a meta-analysis of drought effects on grasslands, and a multifactorial field experiment which combined three years of precipitation reduction and a compost treatment in two Swedish grasslands. We analysed the response of roots and soil microbial communities to drought and compost amendments, and identified environmental factors behind their large spatial variability. Finally, we tested the effects of compost additions on soil carbon storage and its interactions with drought.

  The results of the meta-analysis indicate that, on a global scale, grassland roots and shoots have diverging responses to drought duration and intensity, with long-term climate mediating that difference. At the local scale assessed in the field experiment, we observed that the spatial patterns of soil microbial communities were driven by soil properties and vegetation. Growing season drought affected roots only at trait level, but did not significantly affect microbial communities. Positive effects of compost on aboveground plant productivity and fungal growth were detectable after three years. Compost amendments also increased the percentage of total soil carbon, but no net increase in soil carbon stocks was detected. Spatial variability in roots and microbial communities was larger than the treatment effects, and was important in shaping microbial community composition and determining grassland responses to drought.

  Taken together, these findings suggest that roots and microbial communities are likely to be tolerant to drought a within the timescale of this experiment, but we did not observe an increase soil carbon sequestration or drought resilience when adding compost. This thesis highlights the importance of considering soil processes as complementary to aboveground observations when studying carbon dynamics, predicting ecosystem responses to environmental change, and developing sustainable land management practices.

  Read more about The hidden half of the meadow

• Long-term soil organic carbon changes after cropland conversion to grazed grassland in Southern Sweden

  2024. Anna Johansson (et al.). Soil use and management 40 (1)

  Article

  There is growing awareness of the potential value of agricultural land for climate change mitigation. In Sweden, cropland areas have decreased by approximately 30% over recent decades, creating opportunities for these former croplands to be managed for climate change mitigation by increasing soil organic carbon (SOC) stocks. One potential land-use change is conversion of cropland to grazed grasslands, but the long-term effect of such change in management is not well understood and likely varies with soil type and site-specific conditions. Through sampling of mineral and peatland soils within a 75-year chronosequence of land converted from crop production to grazed grassland, we assessed how time since conversion, catenary position, and soil depth affected SOC storage. The SOC stocks calculated at an equivalent soil or ash mass increased through time since conversion in mineral soils at all topographic positions, at a rate of ~0.65% year−1. Soils at low topographic positions gained the most carbon. Peat SOC stock gains after conversion were large, but only marginally significant and only when calculated at an equivalent ash mass. We conclude that the conversion of mineral soil to grazed grassland promotes SOC accumulation at our sites, but climate change mitigation potential would need to be evaluated through a full greenhouse gas balance.

  Read more about Long-term soil organic carbon changes after cropland conversion to grazed grassland in Southern Sweden

• Climate-dependent responses of root and shoot biomass to drought duration and intensity in grasslands–a meta-analysis

  2023. Daniela Guasconi, Stefano Manzoni, Gustaf Hugelius. Science of the Total Environment 903

  Article

  Understanding the effects of altered precipitation regimes on root biomass in grasslands is crucial for predicting grassland responses to climate change. Nonetheless, studies investigating the effects of drought on belowground vegetation have produced mixed results. In particular, root biomass under reduced precipitation may increase, decrease or show a delayed response compared to shoot biomass, highlighting a knowledge gap in the relationship between belowground net primary production and drought. To address this gap, we conducted a meta-analysis of nearly 100 field observations of grassland root and shoot biomass changes under experimental rainfall reduction to disentangle the main drivers behind grassland responses to drought. Using a response-ratio approach we tested the hypothesis that water scarcity would induce a decrease in total biomass, but an increase in belowground biomass allocation with increased drought length and intensity, and that climate (as defined by the aridity index of the study location) would be an additional predictor. As expected, meteorological drought decreased root and shoot biomass, but aboveground and belowground biomass exhibited contrasting responses to drought duration and intensity, and their interaction with climate. In particular, drought duration had negative effects on root biomass only in wet climates while more intense drought had negative effects on root biomass only in dry climates. Shoot biomass responded negatively to drought duration regardless of climate. These results show that long-term climate is an important modulator of belowground vegetation responses to drought, which might be a consequence of different drought tolerance and adaptation strategies. This variability in vegetation responses to drought suggests that physiological plasticity and community composition shifts may mediate how climate affects carbon allocation in grasslands, and thus ultimately carbon storage in soil.

  Read more about Climate-dependent responses of root and shoot biomass to drought duration and intensity in grasslands–a meta-analysis

• Vegetation, topography, and soil depth drive microbial community structure in two Swedish grasslands

  2023. Daniela Guasconi (et al.). FEMS Microbiology Ecology 99 (8)

  Article

  Soil microbial diversity and community composition are shaped by various factors linked to land management, topographic position,and vegetation. To study the effects of these drivers, we characterized fungal and bacterial communities from bulk soil at four soildepths ranging from the surface to below the rooting zone of two Swedish grasslands with differing land-use histories, each includingboth an upper and a lower catenary position. We hypothesized that differences in plant species richness and plant functional groupcomposition between the four study sites would drive the variation in soil microbial community composition and correlate withmicrobial diversity, and that microbial biomass and diversity would decrease with soil depth following a decline in resource availability.While vegetation was identified as the main driver of microbial community composition, the explained variation was significantlyhigher for bacteria than for fungi, and the communities differed more between grasslands than between catenary positions. Microbialbiomass derived from DNA abundance decreased with depth, but diversity remained relatively stable, indicating diverse microbialcommunities even below the rooting zone. Finally, plant-microbial diversity correlations were significant only for specific plant andfungal functional groups, emphasizing the importance of functional interactions over general species richness

  Read more about Vegetation, topography, and soil depth drive microbial community structure in two Swedish grasslands

• Floral resources in Swedish grasslands remain relatively stable under an experimental drought and are enhanced by soil amendments if regularly mown

  2023. Nina Roth (et al.). Ecological Solutions and Evidence 4 (2)

  Article

  1. One of the main reasons why insect pollinators are declining is a lack of floral resources. In agricultural landscapes, remaining seminatural grasslands play a key role for providing such resources. However, droughts pose an increasing threat to the abundance and continuity of flowers. Soil amendments are a novel management tool for Swedish grasslands aiming to increase carbon sequestration and soil water holding capacity. In this study, we examined how drought is affecting floral resources (i.e. floral units, nectar quantity and nectar continuity) in grasslands with different mowing regimes, and if soil amendments could mitigate potential negative drought effects.
  2. In summer 2019, we set up an experiment combining rain-out shelters (‘drought’), soil amendments (‘compost’) and different mowing regimes (‘mown’ vs. ‘abandoned’) in four extensively managed Swedish grasslands (48 plots, size 2 m²). Between May and August 2021, we counted the floral units nine times in each plot. We derived values for the nectar sugar production per floral unit from an existing database.
  3. We observed a decrease in floral units under drought in the mown, but not in the abandoned plots. Nectar quantity and continuity over the season were not significantly affected by drought across both mowing regimes—in the abandoned plots the nectar provision even extended slightly in duration (towards late summer). The compost treatment had positive effects on the floral units, nectar quantity and continuity (extending it towards early summer) in the mown, but not in the abandoned plots. The plant species in our study reacted differently to the treatments. Most of the nectar was provided by only few species (mainly Lathyrus pratensis, Vicia cracca and Anthriscus sylvestris).
  4. The results are species specific, thus other plant communities might respond differently. However, our experiment shows that nectar provision (based on database values) in grasslands with a native plant community and natural soil conditions remains relatively stable under drought. We also found that soil amendments increase floral resources in managed grasslands.

  Read more about Floral resources in Swedish grasslands remain relatively stable under an experimental drought and are enhanced by soil amendments if regularly mown

• Spring and autumn phenology in an understory herb are uncorrelated and driven by different factors

  2022. Elsa Fogelström (et al.). American Journal of Botany 109 (2), 226-236

  Article

  Premise: Climate warming has altered the start and end of growing seasons in temperate regions. Ultimately, these changes occur at the individual level, but little is known about how previous seasonal life-history events, temperature, and plant-resource state simultaneously influence the spring and autumn phenology of plant individuals.

  Methods: We studied the relationships between the timing of leaf-out and shoot senescence over 3 years in a natural population of the long-lived understory herb Lathyrus vernus and investigated the effects of spring temperature, plant size, reproductive status, and grazing on spring and autumn phenology.

  Results: The timing of leaf-out and senescence were consistent within individuals among years. Leaf-out and senescence were not correlated with each other within years. Larger plants leafed out and senesced later, and size had no effect on growing season length. Reproductive plants leafed out earlier and had longer growing seasons than nonreproductive plants. Grazing had no detectable effects on phenology. Colder spring temperatures delayed senescence in two of three study years.

  Conclusions: The timing of seasonal events, such as leaf-out and senescence in plants can be expressed largely independently within and among seasons and are influenced by different factors. Growing season start and length can often be dependent on plant condition and reproductive status. Knowledge about the drivers of growing season length of individuals is essential to more accurately predict species and community responses to environmental variation.

  Read more about Spring and autumn phenology in an understory herb are uncorrelated and driven by different factors

• Effects of compost amendments and experimental drought on grassland soil microbial communities

  Daniela Guasconi (et al.).

  Read more about Effects of compost amendments and experimental drought on grassland soil microbial communities

• Data of the Insect Biome Atlas: a metabarcoding survey of the terrestrial arthropods of Sweden and Madagascar

  2025. A. Miraldo (et al.). Scientific Data 12

  Article

  We present the data from the Insect Biome Atlas project (IBA), characterizing the terrestrial arthropod faunas of Sweden and Madagascar. Over 12 months, Malaise trap samples were collected weekly (biweekly or monthly in the winter, when feasible) at 203 locations within 100 sites in Sweden and weekly at 50 locations within 33 sites in Madagascar; this was complemented by soil and litter samples from each site. The field samples comprise 4,749 Malaise trap, 192 soil and 192 litter samples from Sweden and 2,566 Malaise trap and 190 litter samples from Madagascar. Samples were processed using mild lysis or homogenization, followed by DNA metabarcoding of CO1 (418 bp). The data comprise 698,378 non-chimeric sequence variants from Sweden and 687,866 from Madagascar, representing 33,989 (33,046 Arthropoda) and 77,599 (77,380 Arthropoda) operational taxonomic units, respectively. These are the most comprehensive data presented on these faunas so far, allowing unique analyses of the size, composition, spatial turnover and seasonal dynamics of the sampled communities. They also provide an invaluable baseline against which to gauge future changes.

  Read more about Data of the Insect Biome Atlas

Show all publications by Daniela Guasconi at Stockholm University