Effects of malathion and nitrate exposure on the zooplankton community in experimental mesocosms
Surface waters are likely to be contaminated by both pesticides and fertilizers. Such contamination can result in changes in community composition if there is differential toxicity to individual taxa. We conducted a fully factorial mesocosm experiment that examined the single and interactive effects of environmentally realistic concentrations of nitrate and malathion on zooplankton communities and phytoplankton productivity. Malathion significantly decreased the abundance of total zooplankton, cyclopoid copepods, copepod nauplii, and Ceriodaphnia, and increased the abundance of rotifers. Nitrate addition generally had no effect on zooplankton; however, Ceriodaphnia abundance was higher in control mesocosms than in nitrate-treated mesocosms. There was only one significant interaction between malathion and nitrate treatments: For Ceriodaphnia, the no malathion, no nitrate mesocosms had much higher abundances than all other combinations of treatments. Without nitrate addition, chl a levels were uniformly low across all malathion treatments, whereas in the presence of nitrate, there were differences among the malathion treatments. In conclusion, our results demonstrate that malathion contamination of aquatic ecosystems can result in changes in the abundance and composition of zooplankton communities. In contrast, nitrate contamination appeared to have much less potential impact on zooplankton communities, either on its own or in interaction with malathion. Our results reinforce the notion that the effects of contaminants on aquatic ecosystems can be complex and further research examining the single and interactive effects of chemical stressors is needed to more fully understand their effects.
KeywordsAgricultural chemicals Chlorophyll a Fertilizer Malathion Nitrate Pesticides Zooplankton
SVK is thankful to United States-India Educational Foundation (USIEF, New Delhi, India) for funding his Fulbright Indo-American Environmental Leadership Program Fellowship. We thank W. and L. Smith, C.J. Dibble, and L. Mills for their help during the experiment. Additional financial support was provided by the Arend McBride Endowed Fund, the Greene Fund, and the Denison University Research Foundation.
Compliance with ethical standards
This experiment was approved by the Denison University Institutional Animal Care and Use Committee (09-006).
- Fenn ME, Baron JS, Allen EB, Rueth HM, Nydick KR, Geiser L, Bowman WD, Sickman JO, Meixner T, Johnson DW, Neitlich P (2003) Ecological effects of nitrogen deposition in the western United States. Bioscience 53(4):404–420.Google Scholar
- Gilliom RJ, Barbash JE, Crawford CG, Hamilton PA, Martin JD, Nakagaki N, Nowell LH, Scott JC, Stackelberg PE, Thelin GP, Woods DM (2006) Quality of our nation’s waters—pesticides in the nation’s streams and ground water, 1992-2001. United States Geological Survey Circular 1291, 172 pGoogle Scholar
- Hanazato T (1998) Response of a zooplankton community to insecticide application in experimental ponds: a review and the implications of the effects of chemicals on the structure and functioning of freshwater communities. Environ Pollut 101(3):361–373. https://doi.org/10.1016/S0269-7491(98)00053-0 CrossRefGoogle Scholar
- Munn MD, Gilliom RJ, Moran PW, Nowell LH (2006) Pesticide toxicity index for freshwater aquatic organisms, 2nd edn. United States Geological Survey Scientific Investigations Report, pp 2006–5148, 81 pGoogle Scholar
- Pagano M, Kodhi MA, Cecchi P, Corbin D, Champalbert G, Saint-Jean L (2003) An experimental study of the effect of nutrient supply and Chaoborus predation on zooplankton communities of a shallow tropical reservoir (Lake Brobo, Côte d’Ivoire). Freshw Biol 48(8):1379–1395. https://doi.org/10.1046/j.1365-2427.2003.01096.x CrossRefGoogle Scholar
- Robertson GP, Vitousek PM (2009) Nitrogen in agriculture: balancing the cost of an essential resource. Ann Rev Environ Res 34(1):97–125. https://doi.org/10.1146/annurev.environ.032108.105046 CrossRefGoogle Scholar
- Roger PA, Kurihara Y (1991) The floodwater biology of tropical wetland rice fields. OBSRAM Monogr 2:211–233Google Scholar
- Šorf M, Davidson TA, Brucet S, Menezes RF, Søndergaard M, Lauridsen TL, Landkildehuis F, Liboriussen L, Jeppesen E (2015) Zooplankton response to climate warming: a mesocosm experiment at contrasting temperatures and nutrient levels. Hydrobiologia 742(1):185–203. https://doi.org/10.1007/s10750-014-1985-3 CrossRefGoogle Scholar
- Tavsanoglu ÜN, Šorf M, Stefanidis K, Brucet S, Türkan S, Agasild H, Baho DL, Scharfenberger U, Hejzlar J, Papustergiadou E, Adrian R, Angeler DG, Zingel P, Çakiroglu AI, Özen A, Drakure S, Søndergaard M, Jeppesen E, Beklioglu M (2017) Effects of nutrient and water level changes on the composition and size structure of zooplankton communities for shallow lakes under different climatic conditions: a pan-European mesocosm experiment. Aquat Ecol 51(2):257–273. https://doi.org/10.1007/s10452-017-9615-6 CrossRefGoogle Scholar