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Theses and Dissertations

Water Resource Management

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The Relationship Between Biofouling Adhesion And Frequency Of Mechanical Cleaning To Control The Recruitment To Clear Coatings, Dylan Thomas Eggers Dec 2023

The Relationship Between Biofouling Adhesion And Frequency Of Mechanical Cleaning To Control The Recruitment To Clear Coatings, Dylan Thomas Eggers

Theses and Dissertations

There is a need to control biofouling on sensors and transparent windows in the marine environment. Clear silicone coatings offer a method to reduce the adhesion strength of marine organisms to the surface, however, these also require mechanical cleaning to maintain the surfaces free of fouling. This research evaluated the performance of eighty seven formulations and took the top two candidates to investigate a) the frequencies of wiping required by a brush to maintain two coatings and uncoated glass surfaces free of fouling and b) the effects of clear silicone coatings fouling release properties on required frequencies. The panels were …


Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill Aug 2023

Optimizing Edge-Of-Field Water Quality Monitoring Methods To Determine The Effects Of Best Management Practices On Nutrient And Sediment Runoff, Mark Hill

Theses and Dissertations

This study investigates the impact on water quality of combined agricultural best management practices cover crop and minimum tillage, alongside an examination of techniques used to collect those samples. Edge-of-field (EOF) water quality samples were collected from 11 working farms during a two-year paired field experiment. Results showed significant reductions in nutrient concentrations, increased discharge, and mixed findings regarding nutrient mass transport post-treatment. A suite of EOF collection techniques were compared using in-situ automated water sampling systems sampling the same runoff events. Sampling protocols influenced nutrient concentrations in composite samples, but unexpected variance in velocity sensors affected measured discharge, making …


Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample Aug 2023

Investigating The Role Of Plant Traits And Interactions In Emergent Wetland Nutrient Removal, Andrew Ryan Sample

Theses and Dissertations

Increasing wetland restoration in the Lower Mississippi Alluvial Valley has been identified as a method to reduce nutrient loading in the Gulf of Mexico. Wetlands have historically been used to treat water through processes facilitated by wetland plants, and relatively few species and plant traits have been identified as important in carrying out these processes. This study focuses on some of those species and traits and aims to identify species differences and plant traits that may be important for wetland nutrient mitigation. Chapter I provides background information on nutrient pollution, wetland biogeochemical mechanisms for nutrient sequestration, and the focal species …


Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze Aug 2023

Benthic Algal And Macroinvertebrate Response To The Removal Of Dreissenid Mussels In The Nearshore Zone Of Lake Michigan, Tyler Alexander Kunze

Theses and Dissertations

Dreissenid mussels (Dreissena polymorpha and Dreissena rostriformis bugensis) have changed the fundamental community structure and biogeochemical processes of the Lake Michigan nearshore zone. There is evidence that dreissenids promote the nuisance growth of benthic algae, especially Cladophora sp. In addition, benthic macroinvertebrates have benefitted from the presence of dreissenid mussels due to the increased structural complexity along with greater nutrient availability in the benthos. These effects of the dreissenid mussel invasion are well documented; however, little is known about how these systems respond to the removal of dreissenid mussels from a once-populated area. Therefore, it is important to further our …


Tree Ring Reconstructions Of Streamflow For The Lower Rio Grande Valley Of Texas, Adedolapo Mutiyat Adeyanju Aug 2022

Tree Ring Reconstructions Of Streamflow For The Lower Rio Grande Valley Of Texas, Adedolapo Mutiyat Adeyanju

Theses and Dissertations

The Rio Grande River is a major water source for people living within the USA-Mexico border. The Rio Grande River has its headwaters in the San Juan Mountains in Colorado and the Sierra Madre Occidental in Mexico before flowing into Texas through El-Paso. The water supply issues facing the Lower Rio Grande Basin (LRGB) are extremely complex from international restrictions to severe climate change. The river shares its flow between the U.S.A and Mexico based on the provisions of the 1944 treaty between the U.S.A and Mexico. The LRGB flow is regulated by releases from Falcon and Amistad Reservoirs managed …


Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju May 2022

Impact Of Climate Oscillations/Indices On Hydrological Variables In The Mississippi River Valley Alluvial Aquifer., Meena Raju

Theses and Dissertations

The Mississippi River Valley Alluvial Aquifer (MRVAA) is one of the most productive agricultural regions in the United States. The main objectives of this research are to identify long term trends and change points in hydrological variables (streamflow and rainfall), to assess the relationship between hydrological variables, and to evaluate the influence of global climate indices on hydrological variables. Non-parametric tests, MMK and Pettitt’s tests were used to analyze trend and change points. PCC and Streamflow elasticity analysis were used to analyze the relationship between streamflow and rainfall and the sensitivity of streamflow to rainfall changes. PCC and MLR analysis …


Evaluating Soil Health Changes Following Cover Crop And No-Till Integration Into A Soybean (Glycine Max) Cropping System In The Mississippi Alluvial Valley, Alexandra Gwin Firth May 2022

Evaluating Soil Health Changes Following Cover Crop And No-Till Integration Into A Soybean (Glycine Max) Cropping System In The Mississippi Alluvial Valley, Alexandra Gwin Firth

Theses and Dissertations

The transition of natural landscapes to intensive agricultural uses has resulted in severe loss of soil organic carbon (SOC), increased CO₂ emissions, river depletion, and groundwater overdraft. Despite negative documented effects of agricultural land use (i.e., soil erosion, nutrient runoff) on critical natural resources (i.e., water, soil), food production must increase to meet the demands of a rising human population. Given the environmental and agricultural productivity concerns of intensely managed soils, it is critical to implement conservation practices that mitigate the negative effects of crop production and enhance environmental integrity. In the Mississippi Alluvial Valley (MAV) region of Mississippi, USA, …


Photocatalytic Degradation Of Organic Contaminants By Titania Particles Produced By Flame Spray Pyrolysis, Noah Babik May 2022

Photocatalytic Degradation Of Organic Contaminants By Titania Particles Produced By Flame Spray Pyrolysis, Noah Babik

Theses and Dissertations

Advanced oxidation of organic pollutants with TiO2 photocatalysts is limited due to the wide bandgap of TiO2, 3.2 eV, which requires ultraviolet (UV) radiation. When nanosized TiO2 is modified by carbon doping, charge recombination is inhibited and the bandgap is narrowed, allowing for efficient photodegradation under visible light. Here, we propose a flame spray pyrolysis (FSP) technique to create TiO2. The facile process of FSP has been successful in preparing highly crystalline TiO2 nanoparticles. Using the same procedure to deposit TiO2 onto biochar, the photocatalyst was doped by the carbonaceous material. The morphology, crystalline and electronic structure of the FSP …


Tackling Chloride Pollution In Southeastern Wisconsin: Halophilic Bacterial Indicators And Policy Alternatives, Elexius Kaitlyn Passante May 2022

Tackling Chloride Pollution In Southeastern Wisconsin: Halophilic Bacterial Indicators And Policy Alternatives, Elexius Kaitlyn Passante

Theses and Dissertations

There are few biological indicators for freshwater systems subjected to high chloride levels. Freshwater systems receive many forms of chloride such as road salts (e.g., NaCl, CaCl2, MgCl2), fertilizers (e.g., KCl), and year-round water softener pollution. The goal our study was to investigate Halomonadaceae populations as prospective biological indicators of chloride-impacted freshwaters. The bacterial family Halomonadaceae are halophiles that generally require the presence of salt to survive, which makes them an attractive candidate in determining chloride impaired areas. Field sediment surveys assessed how salt tolerant and halophilic bacteria abundance corresponded to chloride and conductivity measurements. Colony forming unit (CFU) counts …


Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna May 2022

Hydrologic Modeling Study To Determine Hydrologic Impact Of Resacas On The Lower Laguna Madre Watershed, Antonio L. Reyna

Theses and Dissertations

During a high intensity storm events, a series of catastrophic events occur. These catastrophic events include flooding and destruction of infrastructure. Engineers have determined a method to design for high intensity storms based off hydrologic analysis of previous storms. With this data engineers can determine the outflow of major rivers and streams that may impact infrastructure. By determining the watershed engineers can predict the flow of the water and as well as the location of the outfall. In the Rio Grande Valley, water quality is very important because after rain events stormwater from cities is carried out towards the Laguna …


Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski Mar 2022

Efficiency Mapping And Determination Of Reliability, Resiliency And Vulnerability Of Atmospheric Water Generators In The United States, Erica F. Sadowski

Theses and Dissertations

Atmospheric Water Generators (AWG) extract water from the air using one of three available technologies: refrigeration, sorption, and fog harvesting. A refrigeration device works like a dehumidifier and works best in conditions above 60% relative humidity. A sorption device utilizes a desiccant to extract the water vapor from the air and works in very low humidity levels. A fog harvesting device utilizes a mesh to capture the water vapor from the air and requires 100% relative humidity. In this research, I analyze two refrigeration-based devices and one sorption-based device and their efficacy in providing supplemental water supply. Due to climatological …


The Impacts Of Climate Uncertainty On Streamflow In Andes, Antioquia, Colombia, Kristen R. Roberts Mar 2022

The Impacts Of Climate Uncertainty On Streamflow In Andes, Antioquia, Colombia, Kristen R. Roberts

Theses and Dissertations

Natural hazards, such as hurricanes, wildfires, floods, and droughts impact human systems that rely on predictable patterns in the natural elements with which they interact. Skillful prediction of the impacts of climate change on linked, human-natural systems, like surface water resources, can help ensure physical risks within vulnerable communities are mitigated, resource sustainability is maximized, and intersectoral markets continue to contribute to socioeconomic stability. Due to water resources being a primary conduit through which climate uncertainty impacts people, economies, and ecosystems, its study is worthy of investigation; particularly, where those resources are uncertain and demanded by a variety of competitive …


Engineered Nanostructured Nitrogen-Doped Carbon Network (Ndc) Electrodes With Unprecedented Cycling Stability For Water Capacitive Deionization In Harsh Conditions, Soha Essam Anwar Jun 2021

Engineered Nanostructured Nitrogen-Doped Carbon Network (Ndc) Electrodes With Unprecedented Cycling Stability For Water Capacitive Deionization In Harsh Conditions, Soha Essam Anwar

Theses and Dissertations

Capacitive deionization (CDI) is a feasible low-cost desalination technique for low-to-medium (brackish) salinity water. However, cycling stability and regeneration of the CDI electrodes are the bottlenecks hindering the practical application of the technology on large scale. Oxidation of the electrodes during the sequential adsorption-desorption processes is one of the most challenging problems hindering their long-term cycling performance. Herein, we demonstrated the ability to design and fabricate exceptionally stable CDI electrodes via a one-pot pyrolysis protocol. The optimized pyrolysis of nitrogen-carbon precursors at different temperatures enabled the fabrication of carbon materials with a controlled amount nitrogen dopant (NDCs) with exceptional cycling …


The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen May 2021

The Flow Less Traveled: Documenting Independent Original Research On Fluid Flow Interactions In The Laurentian Great Lakes And Immediate Surroundings, Thomas F. Hansen

Theses and Dissertations

This work is a compilation of several research projects undertaken by the author. Each research effort identifies a problem that has been addressed traditionally using methods that are significantly costly, to such an extent that, in general, funding, convenience, and practicality are primary limiting factors to their effective implementation. In each case, the author has been able to either build upon existing, less expensive alternatives, or even invent novel approaches. The fundamental recurring research question is, can creative, even novel, computational approaches make more efficient use of resources to interpret or present data in such a way as to make …


Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen May 2021

Application Of Deep Learning For Imaging-Based Stream Gaging, Ryan Lee Vanden Boomen

Theses and Dissertations

In the field of water resources management, one vital instrument utilized is the stream gage. Stream gages monitor and record flow and water height within some water body. The United States Geological Survey maintains a network of stream gages at many locations across the country. Many of these sites are also equipped with webcams monitoring the state of the water body at the moment of measurement. Previous studies have outlined methods to approximate stream gage data remotely with limitations such as the requirement of detailed depth information for each site. This study seeks to create a process for training a …


Water Security At United States Air Force Installations, John D. Pollock Mar 2021

Water Security At United States Air Force Installations, John D. Pollock

Theses and Dissertations

Global water security is a growing concern that poses unique challenges that stem from geopolitical arrangement, regional location, and local climate conditions. United States national defense relies on an uninterrupted water supply to sustain operations to carry out its readiness mission. Accurate water security assessments are necessary for adapting to climate factors and to provide essential information to meet the changing needs of human water demand. This research presents how different water metrics are applied at various United States Air Force locations to measure water scarcity. Geographical Information Systems (GIS) software is used to conduct spatial correlation across the United …


Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch Mar 2021

Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch

Theses and Dissertations

A secure water source is essential to the resiliency and readiness of military installations and contingency operation locations, especially those located in the dry climates the US military operates in today. There are multiple issues of concern when identifying water sources, such as security, cleanliness, accessibility, and sustainability. Water resources pose a potential vulnerability to mission readiness in a remote, agile environment, such as a forward operating base (FOB). Having a secure water resource helps facilitate mission readiness in the contingency environment, offering the opportunity to be more resilient and cost-effective. Current water treatment technologies present the possibility to perform …


Numerical And Experimental Investigation Of Aeration Self Mixing By Using Pulsating And Continuous Air Flow, Ahmed Ali Alkhafaji Dec 2020

Numerical And Experimental Investigation Of Aeration Self Mixing By Using Pulsating And Continuous Air Flow, Ahmed Ali Alkhafaji

Theses and Dissertations

Wastewater treatment is considered one of the most common forms of pollution control in the united states. Considered as an integral part of the wastewater treatment, the aeration process is the most energy-consuming process among all the processes that take place in any wastewater treatment plant. According to the United States Environmental Protection Agency (EPA), a wastewater treatment plant is expected to remove at least 85% of the suspended solids and dissolved organic compounds from the wastewater before discharging it to a river or a lake. The normal operation of the aeration process is by compressing air continuously to basin …


Analysis Of Plant Biomass Production Comparing Decoupled Aquaponics Against Equivalent Single-Loop Aquaponic And Hydroponic Systems Growing Lactuca Sativa, Haley Luise Lucas Aug 2020

Analysis Of Plant Biomass Production Comparing Decoupled Aquaponics Against Equivalent Single-Loop Aquaponic And Hydroponic Systems Growing Lactuca Sativa, Haley Luise Lucas

Theses and Dissertations

Aquaponics is an emerging method of agriculture in which fish and plants are grown in an enclosed and recirculating environment. The method mimics a relationship found in nature where fish waste provides nutrients for plants and plants cleanse the water for the benefit of the fish. This symbiotic relationship has proven to be a sustainable method of agriculture in which there is less water use, no need for pesticides or herbicides, recycling of nutrient waste and a smaller spatial footprint. However, the production of both plants and fish in a recirculating aquaponics system has produced less yield and profit when …


Nitrate Transport In The Unsaturated Zone, Patience Bosompemaa May 2020

Nitrate Transport In The Unsaturated Zone, Patience Bosompemaa

Theses and Dissertations

Abundance of nitrate in the soil is a basic issue in agricultural land-use regions, causing eutrophication and pollution of water bodies. The study focuses on the role of a saturated buffer zone (SBZ) to remove nitrate from the groundwater resulting from agricultural activities. The study area is herbaceous SBZ located in central Illinois (40.614382ºN, -89.023542ºW), which lies between a stream and a farm located upgradient. The SBZ has been outfitted with an agricultural runoff treatment system that diverts tile drainage into the subsurface of the SBZ rather than discharging into the stream. Within the SBZ three experimental areas composed of …


Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis May 2019

Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis

Theses and Dissertations

Biofilms are formed when a group of cells of microorganisms stick to each other and often on a surface. The development of biofilm has been a major issue in many fields (medical field, food, chemical, and water industry are a few such fields). In the medical field alone, biofilm infections have reportedly cost over five billion USD in additional healthcare expenses. The food industry usually halts the operation of its plant eight hours, every day to ensure that their equipment and transportation channels are clean and free from any biofilm presence. Similarly, the water and chemical industry need to ensure …


Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis May 2019

Novel Non-Invasive Technology For The Detection Of Thin Biofilm In Piping Systems (Phase - 1), Sachin Davis

Theses and Dissertations

Biofilms are formed when a group of cells of microorganisms stick to each other and often on a surface. The development of biofilm has been a major issue in many fields (medical field, food, chemical, and water industry are a few such fields). In the medical field alone, biofilm infections have reportedly cost over five billion USD in additional healthcare expenses. The food industry usually halts the operation of its plant eight hours, every day to ensure that their equipment and transportation channels are clean and free from any biofilm presence. Similarly, the water and chemical industry need to ensure …


Virus Adsorption To Colloids In Water: Interactions Between Bacteriophage Ms2, Kaolinite, And Fiberglass, Ashlee N. Ellis Mar 2019

Virus Adsorption To Colloids In Water: Interactions Between Bacteriophage Ms2, Kaolinite, And Fiberglass, Ashlee N. Ellis

Theses and Dissertations

Virus adsorption to colloidal particles is an important issue in the water quality community, and it is a particularly important issue for conventional wastewater treatment plants that accept biohazardous waste. Colloids impact the transport of viruses in engineered treatment systems, and they also provide protection against oxidants and other destructive mechanisms. This study evaluated the adsorption of bacteriophage MS2 to colloidal suspensions of kaolinite (KAO) and fiberglass (FG). A series of laboratory batch tests were carried out over a range of experimental conditions to determine kinetic rate constants and characterize bond strength, and computational experiments were done to assess both …


Spatial And Temporal Variation Of Phytoplankton Production In Lake Michigan, Katelyn Alexis Bockwoldt Aug 2018

Spatial And Temporal Variation Of Phytoplankton Production In Lake Michigan, Katelyn Alexis Bockwoldt

Theses and Dissertations

Although many studies have documented decreases in phytoplankton production since the quagga mussel invasion, we currently have a limited understanding of the spatial variation and temporal dynamics of phytoplankton production in Lake Michigan. In this study, phytoplankton production and seston stoichiometry were measured bi-weekly near Milwaukee, three times at two northern basin sites, and along three nearshore-offshore transects from May to November 2017, as well as at 5-6 sites on three whole-lake surveys in 2016 and 2017. Estimates of growth rates were calculated from phytoplankton production and carbon measurements. In spring 2016 and 2017, growth estimates were similar across the …


Application Of Ultraviolet Light Emitting Diodes For The Advanced Oxidation Of Guar Gum, Andrew W. Davenport Mar 2018

Application Of Ultraviolet Light Emitting Diodes For The Advanced Oxidation Of Guar Gum, Andrew W. Davenport

Theses and Dissertations

Guar Gum (GG) is one of the problematic water pollutants connected to hydraulic fracturing. There is a pressing need to investigate appropriate unit operations that can be employed to protect the aquatic environment. This study investigated the use of light-emitting diodes (LEDs) in the advanced oxidation process (AOP) of GG. Chemical oxygen demand (COD) removal provided mixed results, depending on the concentration of hydrogen peroxide (H2O2) in solution, and was between (0-95%) for H2O2-to-GG ratios between 7.0 and 176.3 g H2O2/g GG. COD removal was greatest at the …


Removal Of Perfluorinated Compounds From Post-Emergency Wastewater By Advanced Oxidation Process And Granular Activated Carbon Adsorption, Sean M. Dyson Mar 2018

Removal Of Perfluorinated Compounds From Post-Emergency Wastewater By Advanced Oxidation Process And Granular Activated Carbon Adsorption, Sean M. Dyson

Theses and Dissertations

This research presents a novel approach to remove per- and polyfluoroalkyl substances (PFAS) from aqueous film-forming foam (AFFF) impacted wastewater with high (~100 mg/L) total organic carbon (TOC) concentrations. A treatment-train process was investigated involving an ultraviolet (UV)/hydrogen peroxide (H2O2) advanced oxidation process (AOP) followed by filtration using Calgon Filtrasorb® 600 (F600) granular activated carbon (GAC). UV/H2O2 AOP experiments were conducted to determine whether TOC concentrations could be reduced as a pre-treatment step before filtering the water with F600-GAC. Results showed using UV/H2O2 AOP reduced TOC in solution by > 98% (< 2 mg/L down from 99.1 mg/L). Reducing TOC concentrations was achieved by using a 250 mg/L H2O2 …


Development Of Photocatalysts Supported On Graphitic Carbon Nitride For The Degradation Of Organic Water Pollutants, Atanu Giri Jan 2018

Development Of Photocatalysts Supported On Graphitic Carbon Nitride For The Degradation Of Organic Water Pollutants, Atanu Giri

Theses and Dissertations

Graphitic carbon nitride (g-C3N4) heterojunction composites with the semiconducting metal oxides, CeO2, ZnO and TiO2 are prepared in situ by co-calcination of the precursor materials or by a solvothermal method. The structural, morphological and the optical properties of the prepared materials are studied using various microscopy and spectroscopy techniques. The synthesized composite materials, CeO2/g-C3N4, ZnO/g-C3N4 and TiO2/g-C3N4 are more efficient in the photocatalytic degradation of the water pollutants indigo carmine (IC) and atrazine than the pure metal oxide, g-C …


Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd Jan 2018

Experimental Evaluation Of Uranyl Transport Into Mesoporous Silica Gel Using Fluorescence, Brandon M. Dodd

Theses and Dissertations

This research investigated parameters that can affect the use of nanoporous silica gel as a media for accumulating a detectable amount of uranium. The unique fluorescence of the Uranyl (UO22+) ion was used to evaluate the transport kinetics and accumulation within silica gel in a static fluid and under pressure driven flow. The addition of fluid flow decreased the time constant from on the order of an hour to approximately 2s with a very low fluid velocity of 0.36cm/s. The 0.36cm/s fluid velocity was found to be the critical velocity above which there was no gain in …


Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt Mar 2017

Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt

Theses and Dissertations

This research investigated the efficacy of granular activated carbon (GAC) as a method to treat water impacted with aqueous film forming foam (AFFF) after a firefighting response. Bench-top experiments were conducted and compared to field scale adsorber performance removing mg/L concentrations of PFAS in water contaminated with Military Specification AFFF. Batch tests compared four adsorbents, and determined Calgon F600 GAC and Rembind Plus mixed carbon media had the greatest perfluorooctane sulfonate (PFOS) capacities. Additional batch isotherm experiments using AFFF and higher PFOS concentrations (mg/L) indicated larger amounts of GAC are required (>30mg/L) for effective removal. Full-scale testing simulated an …


Modelling Of Dreissenid Mussel Impacts On Lake Michigan, Chunqi Shen Aug 2016

Modelling Of Dreissenid Mussel Impacts On Lake Michigan, Chunqi Shen

Theses and Dissertations

Invasive dreissenid mussel appear to have profoundly altered Great Lakes food webs and nutrient cycles during the past several decades. Recent declines of phytoplankton were supposed to be highly related with the increase of mussel population. These phytoplankton declines were further found to be coincident with declines in the abundance of planktivorous fish. In addition, the resurgence of Cladophora in Great lakes was estimated to be associated with the high density colonization of mussels. More light is available at lake bottom due to the mussels’ graze effect. The mussels further promote Cladophora growth by fertilizing it with nutrient-rich excrement. And …