Impact of herbivory and competition on lake ecosystem structure: underwater experimental manipulation

0495049 - BC 2019 RIV GB eng J - Journal Article
Vejříková, Ivana - Vejřík, Lukáš - Lepš, J. - Kočvara, Luboš - Sajdlová, Zuzana - Čtvrtlíková, Martina - Peterka, Jiří
Impact of herbivory and competition on lake ecosystem structure: underwater experimental manipulation.
Scientific Reports. Roč. 8, AUG (2018), č. článku 12130. ISSN 2045-2322. E-ISSN 2045-2322
R&D Projects: GA MŠMT(CZ) EE2.3.20.0204; GA MŠMT(CZ) LM2015075; GA MŠMT(CZ) EF16_013/0001782; GA MŠMT(CZ) 7F14316
Institutional support: RVO:60077344
Keywords : rudd scardinius-erythrophthalmus * upper niagara river * invasive cyprinid * fresh-water
OECD category: Ecology
Impact factor: 4.011, year: 2018

Two basic ecological relationships, herbivory and competition, distinctively influence terrestrial ecosystem characteristics, such as plant cover, species richness and species composition. We conducted a cage experiment under natural conditions in an aquatic ecosystem to test the impacts of two treatments combined in a factorial manner: (i) a pulse treatment-removal of dominant competitors among primary producers (macroalgae Chara sp. and Vaucheria sp.), and (ii) a press treatment-preventing herbivore (fish, crayfish) access to caged plots. The plots were sampled once before the treatments were established and four more times within two years. Both treatments had a significantly positive impact on macrophyte cover and species richness and changed the macrophyte species composition. The effect of the macroalgae removal was immediate with the highest species richness occurrence during the first post-treatment monitoring, but the positive effect vanished with time. In contrast, preventing herbivore access had a gradual but long-lasting effect and reached a more steady-state over time. Two of the most common species showed contrasting responses, the palatable Potamogeton pectinatus was most supported by caging, while the distasteful Myriophyllum spicatum preferred open plots. Our findings may be applicable during the revitalisation of aquatic ecosystems that aims to increase macrophyte biodiversity.
Permanent Link: http://hdl.handle.net/11104/0288208