TY  - JOUR
A1  - Sachse, Rene
A1  - Petzoldt, Thomas
A1  - Blumstock, Maria
A1  - Moreira, Santiago
A1  - Paetzig, Marlene
A1  - Ruecker, Jacqueline
A1  - Janse, Jan H.
A1  - Mooij, Wolf M.
A1  - Hilt, Sabine
T1  - Extending one-dimensional models for deep lakes to simulate the impact of submerged macrophytes on water quality
JF  - Environmental modelling & software with environment data news
N2  - Submerged macrophytes can stabilise clear water conditions in shallow lakes. However, many existing models for deep lakes neglect their impact. Here, we tested the hypothesis that submerged macrophytes can affect the water clarity in deep lakes. A one-dimensional, vertically resolved macrophyte model was developed based on PCLake and coupled to SALMO-1D and GOTM hydrophysics and validated against field data. Validation showed good coherence in dynamic growth patterns and colonisation depths. In our simulations the presence of submerged macrophytes resulted in up to 50% less phytoplankton biomass in the shallowest simulated lake (11 m) and still 15% less phytoplankton was predicted in 100 m deep oligotrophic lakes. Nutrient loading, lake depth, and lake shape had a strong influence on macrophyte effects. Nutrient competition was found to be the strongest biological interaction. Despite a number of limitations, the derived dynamic lake model suggests significant effects of submerged macrophytes on deep lake water quality. (C) 2014 Elsevier Ltd. All rights reserved.
KW  - Lake model
KW  - Macrophytes
KW  - Water quality
Y1  - 2014
U6  - https://doi.org/10.1016/j.envsoft.2014.05.023
SN  - 1364-8152
SN  - 1873-6726
VL  - 61
SP  - 410
EP  - 423
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Périllon, Cécile
A1  - Hilt, Sabine
T1  - Groundwater influence differentially affects periphyton and macrophyte production in lakes
JF  - Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica
N2  - Groundwater influx can significantly contribute to nutrient and carbon budgets of lakes, and its influence is the strongest in littoral areas dominated by macrophytes and periphyton. We have reviewed the effects of groundwater-borne nitrogen and phosphorus and dissolved inorganic and organic carbon (DIC, DOC) on these benthic primary producers in lakes. We develop a hypothesis for groundwater effects including the less studied impacts of periphyton shading on macrophytes. Groundwater-borne nutrients and DIC promote both macrophytes and periphyton. Direct studies on groundwater-borne DOC effects are lacking, but coloured DOC contributes to light attenuation and thus can restrict the growth of benthic primary producers. We predict that above certain threshold levels of nutrient influx by groundwater, periphyton and macrophyte biomass should decline owing to shading by phytoplankton and periphyton, respectively. However, because of their higher light requirements, those thresholds should be lower for macrophytes. For macrophytes, a threshold level is also predicted for a shift from DIC limitation to light limitation. Differences in light requirements are expected to result in lower thresholds of DOC loading for declines of macrophytes than periphyton.
KW  - Dissolved inorganic carbon
KW  - Dissolved organic carbon
KW  - Light
KW  - Macrophytes
KW  - Nutrients
KW  - Periphyton
Y1  - 2016
U6  - https://doi.org/10.1007/s10750-015-2485-9
SN  - 0018-8158
SN  - 1573-5117
VL  - 778
SP  - 91
EP  - 103
PB  - Springer
CY  - Dordrecht
ER  -