4a: Multiscale ecosystem management for climate adaptation and mitigation

4a: Multiscale ecosystem management for climate adaptation and mitigation
Conveners:      José R. Paranaíba, Radboud University
                      Sofía Baliña, Radboud University
                      Gabrielle R. Quadra, Radboud University
                      Christian Fritz, Radboud

1. Finding the trade-o/ between maximal biodiversity and flood protection in riparian willow forests in the Netherlands
Corinne van Starrenburg, Alejandra Gijón Mancheño, Daphne van der Wal, Matthijs H. Slegt, Maarten JJ Schrama, Matty Berg Tjeerd J. Bouma, Royal Netherlands Institute for Sea Research (NIOZ) – Department of Estuarine and Delta Systems (EDS), Project WOODY. University: Utrecht University, Faculty of Geosciences, Department of Physical Geography
Riparian forests are essential in temperate regions, providing biodiversity hotspots and various ecosystem functions. Riparian willow forests also play a role in wave attenuation and flood protection. However, with limited space and rising flood safety demands in a changing climate, balancing effective wave reduction with the need to preserve or improve ecological values presents challenges. This study develops a trade-o/ model for three willow forest types—plantation, pollard and wild-grown—seeking to balance biodiversity and wave attenuation. Combining in situ forest structure measurements and insect studies as biodiversity indicators, and wave attenuation modelling, we examine each forest's ecological and flood safety role. Pollard forests show the greatest wave reduction at broader widths, while wild-grown forests provide higher biodiversity potential through habitat heterogeneity and deadwood biomass. Our approach highlights how we can optimize flood protection and especially maximise biodiversity within nature-based solutions, depending on available space and prioritized ecosystem service.

2. Contrasting management practices in livestock production in Uruguay promote differences in total carbon emissions from artificial rural ponds
Maite Colina, Sosa L., Cuassolo F., Passadore C., Calvo C., Heber E., Gallo L., Fox M., Teixeira de Mello F., Davidson T.A., Meerhoff M., Department of Ecology, Faculty of Science, Radboud University. Nijmegen, The Netherlands
More than 170,000 artificial rural ponds have been constructed in Uruguay as a low-cost and effective measure for storing water for cattle and irrigation. We evaluated carbon emissions from artificial ponds subjected to contrasting productive practices, by comparing 13 high-impacted ponds (associated with medium-high cattle density and seeded pastures with chemical fertilization), and 15 low-impacted ponds (associated with low to medium cattle density and native grasslands without chemical fertilization). Carbon dioxide (CO2) and methane (CH4) fluxes were sampled seasonally (excluding winter) for all ponds over one year, and a subset of 12 ponds over two years. The high-impacted ponds always showed the highest CO2 and CH4 emissions, with a significant increase in the emissions with increasing cattle density. Our results stress that carbon emissions from artificial ponds linked to livestock production, significantly differ between productive strategies, giving insights on potential mitigation strategies for carbon emissions from livestock productive activities.

3. A vegetation perspective in Dutch peat meadow restoration: effects of regenerative ditch borders on carbon storage and CO2 emissions
Sanne E. Bethe, Matty P. Berg, Mariet H. Hefting, James T. Weedon, Vrije Universiteit Amsterdam, Amsterdam Institute for Life and Environment, The Netherlands.
The majority of European peatlands are degraded due to conventional grassland-based livestock farming (increased drainage, nutrient inputs, mowing frequency) leading to increased CO2 emissions, land subsidence and reduced biodiversity. We investigated the effects of implementing regenerative ditch borders through changes in vegetation composition on soil carbon storage (litter decomposition) and CO2 emission reduction (soil respiration) in a Dutch fen polder throughout one year. We conclude that variation in litter decomposition between ditch border types was not driven by changes in soil characteristics (e.g. higher moisture levels) but predominantly by lower litter quality of aboveground litter produced at regenerative borders. Model estimates (soil respiration model) indicated reduced CO2 emissions from regenerative ditch borders driven by environmental conditions. Thus, mediated through changes in vegetation composition we can expect increased carbon storage and reduced peat respiration rates in ditch borders after implementing a dynamic transition from the water into the field (regenerative ditch border).

4. Increasing forest resilience against drought through thinning: effects on soil fungal communities and carbon cycling
Steven de Goede, Emilia Hannula, Daniëlle de Hoog, Tanja Bakx-Schotman, Milou van der Putten, Wim van der Putten, Ciska Raaijmakers, Frank Sterck, Ciska Veen, Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen 6700 AB, the Netherlands
Summer droughts are increasing in frequency and severity in Europe with detrimental effects on forests. Reducing the number of trees per area through thinning has been found to improve tree performance during and after drought, but little is known about what happens to the soil. We simulated a forest floor summer drought using rain-out shelters within a replicated block design of different thinning intensities in Dutch Scots pine stands. Soil samples were collected before, during and after drought to track changes in fungal community composition, total and ectomycorrhizal fungal biomass, and extracellular enzymatic activity. Throughout the growing season, soil respiration was regularly measured and litter bags were sequentially harvested to monitor decomposition rates. Generally, effects of thinning were larger than those of drought. However, higher soil respiration and decomposition rates in thinned plots compared to untinned plots, indicating that thinning could mitigate impacts of drought on soil functions.

5. How do root traits mediate effects of grassland management on soil carbon storage?
Jing Zhang, Fons van der Plas, Ciska G.F Veen, Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, Wageningen 6700 AB, the Netherlands
How does grassland management, including fertilization and grazing activities, affect soil carbon storage? Various studies have attempted to answer this question, but their results are highly mixed, with both positive and negative effects of grassland management activities on soil carbon storage. Here, we investigate how changes in plant communities and their root traits in response to grazing and fertilization mediate effects on carbon storage, using a globally replicated experiment (Nut net).Root traits align not only on a “fast-slow” axis (related to how fast roots return construction costs)but also on a “collaboration axis” related to the extent by which roots collaborate with mycorrhiza to obtain resources (outsourcing versus do-it-yourself roots). We first 1) investigate how these root strategies determine which species profit from, or decrease with grazing and fertilization (due to e.g. changes in resource supply and soil disturbances), and 2) how changes in the dominance of species with certain root traits drive changes in soil carbon storage, due to e.g. changes in root litter quality and microbial communities