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Consequences of Anthropogenic Changes in the Sensory Landscape of Marine Animals
Published in S.J. Hawkins, A.L. Allcock, A.E. Bates, L.B. Firth, I.P. Smith, S.E. Swearer, P.A. Todd, Oceanography and Marine Biology, 2019
Ivan Nagelkerken, Scott C. Doney, Philip L. Munday
Humans are affecting the transmission and spectral composition of natural visual cues by altering habitats that maintain high water clarity and by exacerbating the influx of terrestrial materials that reduce water clarity. Riparian vegetation and coastal vegetation such as mangroves, saltmarshes and seagrasses stabilize terrigenous sediments and take up allochthonous nutrients (Gillis et al. 2014), but these habitats have suffered substantial losses in cover globally (Lotze et al. 2006). Owing to changes in land use (i.e. urbanization, forestry, agriculture, river regulation, deforestation, and mining) and weather patterns, increasing loads of sediment, nutrients and particulate organic matter are being released into coastal areas via rivers, artificial channels, stormwater runoff, groundwater discharge and coastal erosion (Howarth et al. 2000, McCulloch et al. 2003). Increased concentrations of particulate and dissolved matter also alter the light environment by reducing visibility and increasing the scattering of natural light, whereas eutrophication leads to plankton blooms that significantly decrease water clarity. Such changes minimize the transmission of relevant visual cues and can affect a range of behaviours such as foraging (e.g. tropical damselfish; Johansen & Jones 2013), activity levels (damselfish; Leahy et al. 2011), habitat choice (damselfish; O'Connor et al. 2016), breeding coloration (three-spined sticklebacks; Wong et al. 2007) and mate selection (Seehausen et al. 1997; e.g. gobies, Pomatoschistus minutus; Jarvenpaa & Lindstrom 2004).
Valuation of Selected Water-Related Ecosystem Goods and Services
Published in Robert A. Young, John B. Loomis, Determining the Economic Value of Water, 2014
Robert A. Young, John B. Loomis
Boyle et al. (1998) and Gibbs et al. (2002) have both used HPVM to measure demand for protecting water quality at freshwater lakes in Maine and New Hampshire, respectively. The primary threat to water clarity to water bodies in these two states is from nutrient loading, resulting in eutrophication and associated algae growth, and the associated reduction in water clarity. Eutrophication is typically the result of nonpoint pollution from land use practices in the watershed (agricultural production, timber harvest, and residential housing development). Measures of the value of improved clarity can help in determining the level of public funding to allocate toward nonpoint pollution regulation.
Eutrophication
Published in Yeqiao Wang, Fresh Water and Watersheds, 2020
Kyle D. Hoagland, Thomas G. Franti
The rate of eutrophication is controlled by the rate at which nitrogen and phosphorus are delivered to a body of water. It is generally accepted that phosphorous is the limiting nutrient for algal growth in lakes.[1,5] Another limiting factor for algal growth is light. As excess phosphorus enters a lake it can trigger high levels of algal growth. Excessive growth, or blooms, can reduce water clarity. Aquatic macrophytes may also thrive under these conditions. This process can increase the productivity of a lake to an extent. When it becomes excessive, the process of cultural eutrophication has begun.
Influence of blueback herring, Alosa aestivalis, on zooplankton in a southeastern US reservoir
Published in Lake and Reservoir Management, 2022
Lee Grove, Ehlana G. Stell, Laura Jay W. Grove, Russell A. Wright, Dennis R. DeVries
Water clarity was measured during each sampling event using a Secchi disk (to the nearest 1 cm). Chlorophyll a (Chl-a) samples were collected from just below the water surface in an opaque brown plastic bottle (500 mL), immediately placed on ice, and returned to the lab to be filtered through a glass fiber filter. A handheld fluorometer (AquaFluor, Turner Designs, Sunnyvale, CA, Welschmeyer 1994) was used to measure Chl-a concentration. In a previous study by Maceina and DeVries (1997), Chl-a was measured by collecting a 300 mL water sample from just below the surface in the eutrophic zone, and the sample was filtered through a 0.45 µm filter, wrapped in foil, stored on ice, and transported to the lab to be evaluated using a Beckman DU-30 spectrophotometer in acetone at 4 C.
KOH ratio effect, characterization, and kinetic modeling of methylene blue from aqueous medium using activated carbon from Thevetia peruviana shell
Published in Chemical Engineering Communications, 2021
Ndifreke Etuk Williams, Nur Pasaoglulari Aydinlik
Methylene blue (MB), which has numerous adverse effects on humans and aquatic environments, is one of the most-used Azo dyes (Fu et al. 2010). MB is used in textiles, pharmaceuticals, cosmetics, plastics, food and paper products (Rafatullah et al. 2010). The increased release of MB into water bodies at high concentrations decreases water clarity, which hinders food consumption for aquatic life and photosynthesis in the aquatic environment (Torane et al. 2010). Also, the dye inhibits the functionality of multiple microbial organisms. The existence of different dye molecules in surface water decreases the penetration of light, which has a direct impact on water flora photosynthesis. Initially, cationic dyes such as MB were used for the production of silk, leather, plastics, paper, cotton mordant with tannin, and ink. Their most appropriate substrates were discovered with the development of synthetic fibers, with an increasingly significant use for dyeing of textiles (Berneth and Bayer 2003). Dyes are now one of the primary sources of water pollution and a significant environmental problem (Zhou et al. 2012; Smith et al. 2016). Cationic dyes are quite visible and stable in water at room temperature (Russo et al. 2016), can be poisonous, and undergo slow and complicated biodegradation. MB has the potential for carcinogenic effects on humans (Kumar et al. 2011) as well as mutagenic and teratogenic effects (Bhattacharyya and Sharma 2005; Kaur et al. 2015).
Alum efficacy 11 years following treatment: phosphorus and macroinvertebrates
Published in Lake and Reservoir Management, 2018
Alan D. Steinman, Michael C. Hassett, Maggie Oudsema, Richard Rediske
All samples except macroinvertebrates were collected on 12 September 2016 from the same 4 locations that were sampled in previous studies (Fig. 1). Macroinvertebrates were collected on 4 October 2016. At each site, dissolved oxygen (DO), pH, temperature, specific conductance, Chl-a, and total dissolved solids (TDS) were measured at the surface, middle, and bottom of the water column using a YSI 6600 sonde. Fluoroprobe measurements of Chl-a were validated with spectrophotometric measurements of extracted Chl-a (Steinman et al. 2017). Photosynthetically active radiation (PAR) profiles were measured using a LiCor Li-193 SA spherical quantum sensor. Secchi disk depth was measured at each site to estimate water clarity. Water samples for P analysis were collected with a Niskin bottle. Water for soluble reactive phosphorus (SRP) analysis was syringe-filtered immediately through 0.45 µm membrane filters into scintillation vials. Samples were stored on ice until transported to the laboratory, within 5 h of collection. TP and SRP samples were stored at 4 C until analysis.