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Environmental Impact Studies for Other Water Resources Projects
Published in Larry Canter, Environmental Impact of Water Resources Projects, 1985
One example of a coastal land creation project is at Marco Island in southwestern Florida. This project includes filling for new land and the excavation of a large group of interconnected lakes (Huber and Brezonik, 1981). The quality of the proposed lakes is of considerable importance, both to the riparian owners and to the nearby estuarine areas that will receive surface discharges. The deep lakes will be stratified due to the influx of hypersaline ground water below a depth of 2.0 m. Density differences are so great across the chemocline that the possibility of overturn is nil. The lakes receive water from surface runoff from the various land uses; from inflow, from regional ground water flow in the shallow fresh water layer, and from direct rainfall. Water is lost by surface runoff, ground water outflows, and evaporation. Annual precipitation in the area is about 50 inches. Residence times of 0.42 and 0.65 years have been calculated for two units of the development. On the basis of phosphorus loading rates, the lakes are expected to be mesotrophic with fair to good water quality. On the whole, predicted water quality is good with Secchi disk transparencies on the order of 1.2 to 1.5 m, and total nitrogen of about 1.3 mg/l. On the basis of nutrient loads, the urban development is expected to have little impact on the estuaries.
Observations of Optical Properties of Natural Waters (The Laurentian Great Lakes)
Published in Robert P. Bukata, John H. Jerome, Kirill Ya. Kondratyev, Dimitry V. Pozdnyakov, of Inland and Coastal Waters, 2018
Robert P. Bukata, John H. Jerome, Kirill Ya. Kondratyev, Dimitry V. Pozdnyakov
Suffice here to say that -trophy is generally (although not universally) considered as a complex duality of epilimnetic water quality and hypolimnetic dissolved oxygen.180 Near-surface water quality and subsurface dissolved oxygen content are themselves functions of a variety of independent variables such as phosphorus, nitrogen, and chlorophyllous pigment concentrations, phytoplankton, zooplankton, and fish and other aquatic denizen populations, thermal depth profiles, primary production, and the underwater light regime. Eutrophication is then defined as the enrichment of waters with plant nutrients (primarily phosphorus and nitrogen) leading to enhanced plant growth (algae and macrophytes) that generally results in some combination of visible surficial algal blooms, floating and/or submerged patches of algae or macrophytes, and increased benthic algae. Decay of this enhanced plant growth can be accompanied not only by the depletion of dissolved aquatic oxygen, but also by the release of a variety of undesirable substances such as CO2, H2S, CH4, corrosive gases, and toxins. The threats of eutrophication to the plant, animal, and human life dependent upon an aquatic basin for sustenance, therefore, can be quite dramatic. A water body displaying such an enhanced nutrient and concomitant enhanced plant growth is termed eutrophic, a water body displaying low nutrient concentrations and/or plant growth is termed oligotrophic, and the term mesotrophic describes an intermediate scenario. Although the impacts and reaction rates of nutrient dynamics are dependent upon climatological, limnological, and oceanological parameters and processes, the symptoms and manifestations of eutrophy as sketched above apply to all waters marine or fresh.
Introduction to cyanobacteria
Published in Ingrid Chorus, Martin Welker, Toxic Cyanobacteria in Water, 2021
Leticia Vidal, Andreas Ballot, Sandra M. F. O. Azevedo, Judit Padisák, Martin Welker
All species are planktonic and primarily found in mesotrophic to eutrophic waters, either inland or coastal, with alkaline or slightly saline conditions. Distributed mainly in tropical and subtropical regions but also during summer in temperate zones.
Evaluation of Physicochemical and Biological Parameters on the Water Quality of ShilabatiRiver, West Bengal, India
Published in Water Science, 2021
Misha Roy, Farzana Shamim, Saibal Chatterjee
Eutrophication is defined as the process through which the water bodies get enriched in nutrient loads which in turn promotes the growth of algae, aquatic species, and various fauna. The water bodies with very low nutrients are known as oligotrophic and moderate nutrients are known as mesotrophic. The deposition of anthropogenic and industrial wastes can result in eutrophication. It is calculated using the following equation (Barnwal et al., 2015; Mishra et al., 2016):
Phosphorus more than temperature controls the phytoplankton community in a deep quarry lake: a combined field and laboratory approach
Published in Inland Waters, 2018
A. Pannard, A. Guislain, M. Chorin, S. Mahé, G. Bouger, A. Crave, B. Le Rouzic, M. Bormans
Lakes resulting from abandoned quarries are widespread worldwide. The large number of quarries used to extract rocks and gravel for various building purposes form a class of post-exploitation water reservoirs that play an increasing socioecological role in transformed landscapes (Miller et al. 1996, Galas 2003). Quarry lakes originating from rock exploitation are generally located on high ground in the landscape and as such are weakly connected to the watershed, often leading to an oligotrophic status. They are also characterized by a low proportion of littoral zone and by a narrow watershed compared with lowland lakes. Consequently, these lakes have a low surface to volume ratio and limited energy and matter exchanges with the surrounding environment, leading to a high thermal stability over the year and even meromixis (Boehrer and Schultze 2008). Hence, quarry lakes are often deep, stable, clearwater oligotrophic or mesotrophic systems and are therefore often the focus of recreational activities, such as swimming or diving. Although their physical and chemical characteristics have received some attention because of potential water quality problems associated with low oxygen and carbon dioxide (CO2) or methane release during overturn (Boehrer et al. 2016, Horn et al. 2017), they are still much understudied, and their ecological significance and phytoplankton dynamics are almost unknown (Bilý and Pithart 2002). Low phytoplankton biomass with a specific phytoplankton community can be expected in these physically stable waterbodies with almost zero inputs from the catchment. Unknown is which factor limits the species composition: nutrient availability, temperature, or the synergy of both. Nutrients and temperature are believed to be the 2 most important factors driving phytoplankton community structures in lakes (Anneville et al. 2005, Elliott et al. 2005, Jeppesen et al. 2005); however, these factors have not been explored to explain phytoplankton community structures in quarry lakes.