PCModel: Ecosystem models PCLake, PCLake+ en PCDitch
NIOO has a long history in developing, maintaining, applying and doing research with the ecosystem models PCLake(+) and PCDitch. Among others, NIOO maintains the PCmodel github page where the model can be found and downloaded from: https://github.com/pcmodel

In the latest decade, the application of DNA sequencing technology has resulted in the discovery of many species new to science. Most of these species have long remained undetected because they were difficult to distinguish morphologically from described species. In this project, we have applied reverse taxonomy with the aim to detect and describe formerly unrecognized ‘cryptic’ species in the species complex Brachionus calyciflorus, a very commonly studied and cosmopolitan freshwater rotifer. The combination of a molecular and morphological analysis resulted in the discovery and (re)description of four species, i.e. B. calyciflorus s.s., B. elevatus, B. fernandoi and B. dorcas (Papakostas et al., 2016; Michaloudi et al., 2018). While some evidence accumulates that the species differ ecologically (Papakostas et al., 2016; Zhang et al. 2020), we have also demonstrated that reproductive barriers between the two most closely related sibling species, B. calyciflorus s.s. and B. elevatus are strong but not impenetrable (Zhang & Declerck 2021, 2022). The observation of hybridization leads to the question how species maintain their integrity in the face of genetic exchange. Currently, we perform a phylogeographic analysis with the aim to study the geographic structure of molecular divergence within the species complex and the degree to which this bears the signature of hybridization. Future studies will also focus on ecological divergence and its implications for the long-term fate and coexistence of these sibling species.

In many ecosystems, human impacts have strongly altered the quantities and relative ratios of elements such as carbon, phosphorus, nitrogen. This may have important consequences, not only for the plants, but also for the animals that use these plants as food source. Animals need specific ratios of elements for their optimal growth, survival and reproduction. Deviations from these ratios (‘stochiometric mismatch’) may lead to substantial performance reductions with important ecological and microevolutionary consequences. In this project, we investigate how populations of zooplankton herbivores respond to and cope with both shortage and excess of critical elements in their diet, both from ecological and microevolutionary perspectives.

Rapid evolutionary adaptation of zooplankton to anthropogenic stressors

Water fleas (Cladocera) form a species rich group that play an important ecological role in freshwater ecosystems, such as ponds, lakes, ditches, canals and pools. Biodiversity research on this group is hampered because of the highly specialized taxonomic expertise and large time investments required for the analysis of samples. However, the rapid development of next generation sequencing (NGS) techniques creates the prospect of automatizing the identification of species in community samples through bulk DNA sequence analysis (metabarcoding). To be reliable and successful, such approach requires an extensive and curated library of regionally acquired barcodes. Unfortunately, West-European populations of cladoceran species are not or only very poorly represented in publicly available databases (e.g. Boldv4, NCBI). The aim of this project therefore is to establish a high-quality, curated reference library for the marker gene COI (cytochrome c oxidase I) of all cladoceran species in The Netherlands. For this, a large variety of freshwater habitats are being sampled across The Netherlands. Cladocerans retrieved from these samples are identified individually by Martin Soesbergen (Rijkswaterstaat), an expert in Cladoceran taxonomy, after which their COI gene is sequenced at NIOO-KNAW. The resulting reference library will strongly facilitate end users to identify unknown specimens and contribute to the detection of cryptic diversity. Together with a bioinformatics pipeline, also assembled at NIOO-KNAW, this library will strongly enhance our ability to monitor and survey zooplankton communities in The Netherlands.

Natuur in Productie: visecologie op de Marker Wadden (NiPFish)

MANTEL (Management of Climatic Extreme Events in Lakes & Reservoirs for the protection of Ecosystem Services) is a Marie Sklodowska-Curie European Joint Doctorate Innovative Training Network that trained a cohort of Early Stage Researchers (ESRs) to investigate the effects of extreme climatic events on water quality. As one of 12 ESRs, Qing's MANTEL project focus on mitigating negative impacts of extreme events on the sustained provision of lake ecosystem services.

The outputs will support stakeholders through development of measures that mitigate the negative consequences of extreme events, including toxic cyanobacterial blooms, and runoff induced high nutrient loads. Lowering the trophic status of surface waters is expected to increase resilience against predicted global warming and therewith reduce problematic cyanobacterial blooms. Cost-efficient mitigation calls for a tailor made benefit oriented restoration plan, building on an arsenal of restoration techniques, combined with innovative techniques (e.g. geo-engineering techniques).

Qing will be primarily based in the Netherlands Institute of Ecology, Netherlands, supervised by Dr Lisette de Senerpont Domis, and will be co-supervised by and spend study time with Dr Miquel Lurling, Wageningen University, and Dr. Rafa Marcé, Catalan Institute for Water Research, Spain. The PhD will be awarded by Wageningen University.

More information about this project can be found: https://www.mantel-itn.org/

Using system diagnosis to assess pressures on aquatic systems