title: Leaf litter leachates have the potential to increase lifespan, body size, and offspring numbers in a clone of Moina macrocopa.
abstract: Leaf litter processing is one major pathway of the global organic carbon cycle. During this process, a variety of small reactive organic compounds are released and transported to the aquatic environment, and may directly impact aquatic organisms as natural xenobiotics. We hypothesize that different forest stockings produce different leachate qualities, which in turn, stress the aquatic communities and, eventually, separate sensitive from tolerant species. Particularly, leachates from coniferous trees are suspected to have strongly adverse impacts on sensitive species. We exposed individuals of a clone of the model organism, Moina macrocopa, to comparable concentrations (approximately 2mM) of litter leachates of Norway spruce, Picea abies, Colorado blue spruce, Picea pungens, black poplar, Populus nigra, and sessile oak, Quercus petraea. The animals were fed ad libitum. The following life trait variables were recorded: growth, lifespan, and lifetime offspring. To identify, whether or not exposure to litter leachates provokes an internal oxidative stress in the exposed animals we measured the superoxide anion radical scavenging capacity via photoluminescence. Except of P. abies, exposure to the leachates reduced this antioxidant capacity by approximately 50%. Leachate exposures, except that of Quercus, increased body size and extended lifespan; furthermore, particularly the leachates of both Picea species significantly increased the offspring numbers. This unexpected behavior of exposed Moina may be based on food supplements (e.g., high carbohydrate contents) in the leachates or on yet to be identified regulatory pathways of energy allocation. Overall, our results suggest that the potentially adverse effects of litter leachates can be overruled by either bacterial-growth supporting fractions in the leachates or an internal compensation mechanism in the Moina individuals.
authors: Humboldt-Universität zu Berlin, Department of Biology, Laboratory of Freshwater and Stress Ecology, Arboretum, 12437 Berlin, Germany.
authors: Sylva
authors: S
authors: Hofmann
authors: Maxim A
authors: MA
authors: Timofeyev
authors: Anke
authors: A
authors: Putschew
authors: Nadine
authors: N
authors: Saul
authors: Ralph
authors: R
authors: Menzel
authors: Christian E W
authors: CE
authors: Steinberg
mesh_terms: D000818:Animals; D049628:Body Size; D002244:Carbon / Q000378:metabolism*; D033361:Cladocera / Q000033:anatomy & histology / Q000187:drug effects* / Q000502:physiology; D004781:Environmental Exposure / Q000032:analysis; D018384:Oxidative Stress; D028222:Picea / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry*; D032107:Populus / Q000737:chemistry; D029963:Quercus / Q000737:chemistry; D012098:Reproduction / Q000187:drug effects; D013312:Stress, Physiological; D014873:Water Pollutants / Q000494:pharmacology; D015262:Xenobiotics / Q000494:pharmacology*
chemical_list: D014873:Water Pollutants; D015262:Xenobiotics; D002244:Carbon