Effects of Invasive Watermilfoil on Primary Production in Littoral Zones of North-Temperate Lakes

Species invasions are changing aquatic ecosystems worldwide. Submerged aquatic macrophytes control lake ecosystem processes through their direct and indirect interactions with other primary producers, but how these interactions may be altered by macrophyte species invasions in temperate lakes is poorly understood. We addressed whether invasive watermilfoil (IWM) altered standing crops and gross primary production (GPP) of other littoral primary producers (macrophytes, phytoplankton, attached algae, and periphyton) in littoral zones of six Michigan lakes through a paired-plot comparison study of sites with IWM (standardized abundance 7–56%) compared to those with little or no IWM (standardized abundance 0–2%). We found that primary producer standing crops and the GPP of epiphytes, phytoplankton, and benthic periphyton were variable among lakes and not significantly different between paired study plots. Macrophyte standing crops predicted rates of benthic periphyton GPP, and standing crops of all other primary producers across all study plots. Overall, our results suggest that the effects of IWM on other primary producers in littoral zones may be lake-specific, and are likely dependent on the density of IWM, or whether it is functionally similar to other native species that it replaces or co-exists with. Moreover, in lakes where IWM is established but does not dominate macrophyte assemblages, the effects on littoral zone productivity may be minimal. Instead, overall macrophyte biomass is the primary factor controlling the rates of production and biomass of the other littoral zone primary producers, as has long been understood and observed in lake ecosystems.

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Gross primary production and respiration differences among littoral and pelagic habitats in northern Wisconsin lakes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f06-018 ◽

2006 ◽

Vol 63 (5) ◽

pp. 1130-1141 ◽

Cited By ~ 57

Author(s):

George H Lauster ◽

Paul C Hanson ◽

Timothy K Kratz

Keyword(s):

Primary Production ◽

Surface Waters ◽

Gross Primary Production ◽

Free Water ◽

Lake Metabolism ◽

Trophic Conditions ◽

Littoral Zones ◽

Ecosystem Production ◽

Littoral Area ◽

Littoral Habitats

Net ecosystem production (NEP) trends among lakes have been ascribed to differences in nutrient and allochthonous carbon inputs, but little is known on how different habitats within lakes contribute to these trends. We sampled pelagic and littoral surface waters using sonde (i.e., free-water) and bottle methods concurrently in lakes spanning a range of trophic conditions. We considered whether the typically higher metabolism estimates found with sonde methods are due to contributions from littoral habitats not reflected by bottle estimates. We sought the source of littoral contributions by selecting sites with maximum differences in macrophyte abundance. Sonde estimates for pelagic primary production and respiration were twothree times greater than bottle estimates. Sonde/bottle ratios were higher in productive lakes and lakes with more littoral area. Bottle estimates were similar among all sites, and sonde estimates in macrophyte-poor sites were similar to pelagic sondes. However, sonde estimates in macrophyte-rich areas were fournine times greater than bottle estimates. Results suggest littoral zones increase whole-lake NEP in eutrophic systems, whereas the Sphagnum mat surrounding dystrophic lakes decreases NEP. Non-planktonic organisms associated with macrophytes provide important littoral contributions to whole-lake metabolism and to understanding NEP trends among lakes.

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A Framework for Understanding Variation in Pelagic Gross Primary Production of Lake Ecosystems

Ecosystems ◽

10.1007/s10021-018-0226-4 ◽

2018 ◽

Vol 21 (7) ◽

pp. 1364-1376 ◽

Cited By ~ 19

Author(s):

Patrick T. Kelly ◽

Christopher T. Solomon ◽

Jacob A. Zwart ◽

Stuart E. Jones

Keyword(s):

Primary Production ◽

Gross Primary Production ◽

Lake Ecosystems

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Implications of climate warming for Boreal Shield lakes: a review and synthesis

Environmental Reviews ◽

10.1139/a07-002 ◽

2007 ◽

Vol 15 (NA) ◽

pp. 99-112 ◽

Cited By ~ 83

Author(s):

W. Keller

Keyword(s):

Climate Change ◽

Native Species ◽

Large Scale ◽

Weather Conditions ◽

Biological Interactions ◽

Lake Ecosystems ◽

Multiple Stressor ◽

Species Invasions ◽

Boreal Shield ◽

Shield Lakes

Climate change is a reality. A warming climate will have large effects on lakes of the Boreal Shield. Our ability to forecast these effects, however, is hampered by a very incomplete understanding of the actual interactions between weather and many aspects of lake ecosystems. Climate change will affect lakes in very complex ways. Changing weather conditions will have direct effects on thermal habitats; however, there will also be very important indirect effects on lake ecosystems through influences on watershed processes that affect the thermal and chemical characteristics of lakes. Altered habitat conditions will affect the resident biota in both positive and negative ways and may favour range expansions of some native and non-native species. Our understanding of the altered biological interactions that will structure lake communities in a warmer climate is still limited, making the prediction of biological outcomes very difficult. Modelling efforts, experiments and empirical analyses of relationships between important attributes of lakes, lake communities, and weather conditions in the past are beginning to further our ability to predict likely future effects. Much more work is needed in all these research areas to further our understanding of the probable effects of climate change on Boreal Shield lakes. Because of the potential interactions of climate with other large-scale environmental stressors such as UV-B irradiance, exotic species invasions, base cation depletion, and acidification, future studies need to consider multiple stressor effects.

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Taxonomy and distribution of diatoms on the Turkish Mediterranean Coast, Dalyan (Muğla)

Mediterranean Marine Science ◽

10.12681/mms.17293 ◽

2020 ◽

Vol 21 (1) ◽

pp. 201 ◽

Cited By ~ 2

Author(s):

MUHAMMET AYDIN KALELI ◽

JOHN PATRICK KOCIOLEK ◽

CÜNEYT NADIR SOLAK

Keyword(s):

Primary Production ◽

Geographic Distribution ◽

Littoral Zone ◽

Aegean Sea ◽

Coastal Ecosystems ◽

Mediterranean Coast ◽

Littoral Zones ◽

O2 Production ◽

Littoral Diatoms

Diatoms are one of the components in the littoral zone and the most productive in terms of O2 production and primary production. Despite their importance in these coastal ecosystems, the diatoms of littoral zones of Turkish coastlines have been understudied. In this report, we document the littoral diatoms from Dalyan Iztuzu Beach at the southeast coasts of Aegean Sea. Samples were collected from 6 stations in Dalyan Beach between 2012 and 2016. We report here on the occurrence of 9 genera including, Catenula Mereschkowsky, Cymatosira Grunow, Dimeregramma Ralfs, Diplomenora Blazé, Eunotogramma Weisse, Meloneis Louvrou, Danielidis & Economou-Amilli, Neohuttonia Kuntze, Plagiogramma Greville and Tetramphora Mereschkowsky, as well as 40 taxa as newly-recorded from Turkey. The newly-recorded diatoms are characterized in terms of their morphology and illustrated with light micrographs. For each species, their habitat and geographic distribution along the coasts are discussed.

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