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Small water bodies in agricultural landscapes

Small water bodies are an important part of freshwater ecosystems. They support higher proportions of biodiversity compared to larger lakes or rivers and largely contribute to inland water–carbon fluxes. At the same time, intensive agriculture is threatening first and foremost these important ecosystems by pesticide pollution. However, only a disproportionally low amount of studies addresses pesticide occurrence and impacts in small water bodies despite their spatial dominance among the water bodies receiving pesticide inputs.

Human lakeshore development

Lakes are used in multiple ways for fishing, boating, navigation, beach recreation, drinking water supply, and nature conservation. Thereby, lakeshores suffer substantially from the anthropogenic, hydromorphological degradation which affects diversity of habitats and of benthic invertebrates colonizing the littoral zone.

Relevant hydromorphological processes in river systems

A multitude of pressures are co-occuring in river ecosystems and act simultaneously on important processes and variables. Therefore, the different pressures cannot be seen as individual drivers of ecological change. To guide river rehabilitation and nature conservation, clear diagnoses of existing deficits are neccessary that involve the complex interactions between hydrology, morphology, existing habitats, water chemistry and the thermal regime.
Lorenz S, Wolter C (2019) Quantitative response of riverine benthic invertebrates to sediment grain size and shear stress. Hydrobiologia 834: 47-61.
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Lorenz S, Leszinski M, Graeber D (2016) Meander reconnection method determines restoration success for macroinvertebrate communities in a German lowland river. International Review of Hydrobiology 101:123-131.
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Lorenz S, Martinez-Fernández V, Alonso C, Mosselman E, García de Jalón D, González del Tánago M, Belletti B, Hendriks D, Wolter C (2016) Fuzzy cognitive mapping for predicting hydromorphological responses to multiple pressures in rivers. Journal of Applied Ecology 53(2):559-566.

Wolter C, Lorenz S, Scheunig S, Schomaker C, Martinez-Fernandez V, Alonso C, Garcia de Jalon D, Gonzalez del Tanago M, Mosselman E, Hendriks D, Belletti B (2015) Hydromorphic change and biotic response challenge effective river rehabilitation. In: Angelopolous, N., T. Buijse et al. [eds.] Proceedings of the International Conference on River and Stream Restoration "Novel Approaches to Assess and Rehabilitate Modified Rivers". FP7 REFORM deliverable 7.5. pp 79-84.

Muhar S, Aroviita J, Baattrup-Pedersen A, Brabec K, Ecke F, Giełczewski M, Hering D, Januschke K, Kaufmann S, Lorenz AW, Lorenz S,  Paillex A, Poppe M, Rääpysjärvi J, Verdonschot PFM (2014) Methods. In: Kail J, Lorenz AW, Hering D (Eds) Effects of large-and small-scale river restorationon hydromorphology and ecology. FP7 REFORM deliverable 4.3.

Lorenz S, Scheunig S, Schomaker C, Wolter C (2014) Biotic response to hydromorphologic changes - what to adress? Proceedings of the 10th International Symposium on Ecohydraulics, 23-27 June 2014, Trondheim, Norway, 4 pp.

Garcia de Jalón D, Alonso C, González del Tango M, Martinez V, Gurnell A, Lorenz S, Wolter C, Rinaldi M, Beletti B, Mosselman E, Hendriks D, Geerling G (2013) Review on pressure effects on hydromorphological variables and ecologically relevant processes. FP7 REFORM deliverable 1.2.

Wolter C, Lorenz S, Scheunig S, Lehmann N, Schomaker C, Nastase A, Garcia de Jalón D, Marzin A, Lorenz A, Kraková M, Brabec K, Noble R (2013) Review on ecological response to hydromorphological degradation and restoration. FP7 REFORM deliverable 1.3.

Graeber D, Pusch M, Lorenz S, Brauns M (2013) Cascading effects of flow reduction on the benthic invertebrate community in a lowland river. Hydrobiologia 717:147-159.
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Effects of ship-induced waves on aquatic ecosystems

Most larger water bodies worldwide are used for navigation, and the intensity of commercial and recreational navigation is expected to further increase. Navigation profoundly affects aquatic ecosystems. To facilitate navigation, rivers are trained and developed, and the direct effects of navigation include chemical and biological impacts. Propagating ships create hydrodynamic alterations, often simply summarized as waves. Although ship-induced waves are recognized as influential stressors, knowledge on their effects is poor.