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Water quality

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2020

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Full-Text Articles in Physical Sciences and Mathematics

Tree Canopy Effects On Roof-Harvested Rainwater In East Texas, Kimberly Gamez Dec 2020

Tree Canopy Effects On Roof-Harvested Rainwater In East Texas, Kimberly Gamez

Electronic Theses and Dissertations

Nine experimental metal roofs with rainwater harvesting systems were constructed and water quality parameters were measured in 2016-2017 in order to evaluate the effects of arboreal overhang on roof-harvested rainwater quality collected in East Texas. Three treatments were evaluated: Rainwater collected from roofs without any overhanging tree vegetation, rainwater collected from roofs under predominantly Southern yellow pine tree cover, and rainwater collected from roofs under predominantly hardwood tree cover. Rainwater was collected from these roofs for one year. The effects of canopy cover on water quality parameters, comparison to drinking water standards, first-flush efficiency, and seasonal effects were evaluated.

Significant …


Water Quality In Terms Of Metals During Flooding In Two Ecosystems Of The Conchos Watershed, Mexico: Rangeland‐Forest And Urban Areas, H. Rubio, J. Jiménez, K. Wood, M. Gutierrez Nov 2020

Water Quality In Terms Of Metals During Flooding In Two Ecosystems Of The Conchos Watershed, Mexico: Rangeland‐Forest And Urban Areas, H. Rubio, J. Jiménez, K. Wood, M. Gutierrez

IGC Proceedings (1997-2023)

No abstract provided.


Impacts Of Grazing Management On Cattle Distribution And Non‐Point Source Pollution From Pastures In The Central United States, M. Haan, J. Russell, D. Bear, D. Morrical Nov 2020

Impacts Of Grazing Management On Cattle Distribution And Non‐Point Source Pollution From Pastures In The Central United States, M. Haan, J. Russell, D. Bear, D. Morrical

IGC Proceedings (1997-2023)

No abstract provided.


Grassland And Water Resources: Recent Trends And Future Challenges In Temperate Zones, Benoît Marc Oct 2020

Grassland And Water Resources: Recent Trends And Future Challenges In Temperate Zones, Benoît Marc

IGC Proceedings (1997-2023)

No abstract provided.


Essays On Environmental And Health Economics., Prachi Singh Dr. Oct 2020

Essays On Environmental And Health Economics., Prachi Singh Dr.

Doctoral Theses

This thesis consists of three empirical essays that investigate issues in environmental and health economics. The main focus of this thesis is to study how environmental degradation or interventions in this domain can affect demographic and health outcomes of the population in developing countries. The first chapter explores the effect of an information campaign about arsenic contamination in Bangladesh on marriage market outcomes. This study finds that providing information about negative effects of arsenic consumption had an unintended consequence in the marriage market. Specifically, information about lower fertility, skin lesions, cancers and higher mortality related to arsenic exposure induced individuals …


Trends In Water Quality Of Cave Pools At Timpanogos Cave National Monument, July 2008–September 2018, Rebecca Weissinger, Andy Armstrong, Kirsten Bahr, Chris Groves Oct 2020

Trends In Water Quality Of Cave Pools At Timpanogos Cave National Monument, July 2008–September 2018, Rebecca Weissinger, Andy Armstrong, Kirsten Bahr, Chris Groves

Crawford Hydrology Laboratory

No abstract provided.


Water Quality Assessment In The Occurrence Of Acanthaster Spp. (Crown-Of-Thorns Starfish, Cots) On Coral Reefs In Menjangan Island, Bali, Indonesia, Novia Arinda Pradisty, Eghbert Elvan Ampou, Rizki Hanintyo Sep 2020

Water Quality Assessment In The Occurrence Of Acanthaster Spp. (Crown-Of-Thorns Starfish, Cots) On Coral Reefs In Menjangan Island, Bali, Indonesia, Novia Arinda Pradisty, Eghbert Elvan Ampou, Rizki Hanintyo

Makara Journal of Science

Aquatic stressors are known to cause biological impairment that can result in biodiversity loss in several Marine Protected Areas (MPA), including in Menjangan Island, West Bali National Park. The objectives of this study were to correlate the changes in water quality parameters with the biological effect of Crown-of-Thorns starfish (CoTS) population dynamics and to assess the most applicable parameters for continuous environmental monitoring. Field observations and surveys were conducted three times in 2017, during the wet season, dry season and season transition, in order to assess the effect of seasonal variability. Redundancy Analysis (RDA) was performed to determine the relationship …


Occupancy And Abundance Of Stream Salamanders Along A Specific Conductance Gradient, Jacob M. Hutton, Steven J. Price, Simon J. Bonner, Stephen C. Richter, Christopher D. Barton Sep 2020

Occupancy And Abundance Of Stream Salamanders Along A Specific Conductance Gradient, Jacob M. Hutton, Steven J. Price, Simon J. Bonner, Stephen C. Richter, Christopher D. Barton

Forestry and Natural Resources Faculty Publications

In the Central Appalachians (USA), mountaintop-removal mining accompanied by valley fills often leads to streams with elevated specific conductivity (SC). Thus, the ionic composition of freshwaters in this region is hypothesized to be a driver of the distribution and abundance of freshwater taxa, including stream salamanders. We examined the association between SC and stream salamander populations by conducting salamander counts in 30 southeastern Kentucky streams across a continuous gradient of SC that ranged from 30 to 1966 μS/cm. We counted 2319 salamanders across 5 species and, using a hierarchical Bayesian version of the N-mixture model, found a negative association between …


2020 Chesapeake Bay Dead Zone Report, Virginia Institute Of Marine Science, Anchor Qea Sep 2020

2020 Chesapeake Bay Dead Zone Report, Virginia Institute Of Marine Science, Anchor Qea

Reports

The “Dead Zone” of the Chesapeake Bay refers to a volume of bottom water that is characterized by dissolved oxygen concentrations less than 2 mg/L, which is too low for aquatic organisms such as fish and blue crabs to thrive.The Chesapeake Bay experiences such “hypoxic”conditions every year, with the severity varying from year to year, depending on nutrient and freshwater inputs, wind, and temperature. Multiple metrics are used to relate the severity of hypoxia between different years:

  • Hypoxic Duration (days): The number of days in a given year between the first and last day of hypoxic conditions exceeding 2 km3in …


A Machine‐Learning‐Based Model For Water Quality In Coastal Waters, Taking Dissolved Oxygen And Hypoxia In Chesapeake Bay As An Example, Xin Yu, Jian Shen, Jiabi Du Aug 2020

A Machine‐Learning‐Based Model For Water Quality In Coastal Waters, Taking Dissolved Oxygen And Hypoxia In Chesapeake Bay As An Example, Xin Yu, Jian Shen, Jiabi Du

VIMS Articles

Hypoxia is a big concern in coastal waters as it affects ecosystem health, fishery yield, and marine water resources. Accurately modeling coastal hypoxia is still very challenging even with the most advanced numerical models. A data‐driven model for coastal water quality is proposed in this study and is applied to predict the temporal‐spatial variations of dissolved oxygen (DO) and hypoxic condition in Chesapeake Bay, the largest estuary in the United States with mean summer hypoxic zone extending about 150 km along its main axis. The proposed model has three major components including empirical orthogonal functions analysis, automatic selection of forcing …


Use Of Citizen Science In Monitoring Groundwater Quality: A Case Study From Nebraska, Christopher Olson Aug 2020

Use Of Citizen Science In Monitoring Groundwater Quality: A Case Study From Nebraska, Christopher Olson

School of Natural Resources: Dissertations, Theses, and Student Research

Citizen science has a key role in modernizing effective communication between professional scientists and the general public. However, citizen science differs to that of professional science due to equipment and experience and is a topic argued against citizen science. However, technology in water quality testing has developed in simplicity and affordability to a point where high school students, with hands-on training, can collect groundwater samples and test for quality themselves. Nebraska groundwater quality is a critical part of the state and can utilize high school students as citizen scientists for their communities. High school students from rural communities across Nebraska …


Water Quality Study Of The Muchea Livestock Truck Wash, Simon Clarendon, David Weaver, Justin L.M Hardy, Claire Coffey, Robert Summers, David Rogers, Peta Richards Aug 2020

Water Quality Study Of The Muchea Livestock Truck Wash, Simon Clarendon, David Weaver, Justin L.M Hardy, Claire Coffey, Robert Summers, David Rogers, Peta Richards

Resource management technical reports

Across Australia there is a lack of information on the quality of the water discharged from facilities that are used to wash livestock trucks. This water quality scoping study partially fills that information gap and provides a starting point for future planning, design and construction of livestock truck washes.

The study was undertaken in 2011–12 at the Western Australian Muchea Livestock Centre, and aimed to gain insights into water quality associated with the truck wash facility at that site. These insights can help to inform the planning for further construction of truck wash facilities throughout the state, and whether disposing …


A Geochemical And Statistical Investigation Of The Big Four Springs Region In Southern Missouri, Jordan Jasso Vega Aug 2020

A Geochemical And Statistical Investigation Of The Big Four Springs Region In Southern Missouri, Jordan Jasso Vega

MSU Graduate Theses

The Big Four Springs region hosts four major first-order magnitude springs in southern Missouri and northern Arkansas. These springs are Big Spring (Carter County, MO), Greer Spring (Oregon County, MO), Mammoth Spring (Fulton County, AR), and Hodgson Mill Spring (Ozark County, MO). Based on historic dye traces and hydrogeological investigations, these springs drain an area of approximately 1500 square miles and collectively discharge an average of 780 million gallons of water per day. The rocks from youngest to oldest that are found in Big Four Springs region are the Cotter and Jefferson City Dolomite (Ordovician), Roubidoux Formation (Ordovician), Gasconade Dolomite …


Ceramic Water Filter For Point-Of-Use Water Treatment In Developing Countries: Principles, Challenges And Opportunities, Haiyan Yang, Shangping Xu, Derek E. Chitwood, Yin Wang May 2020

Ceramic Water Filter For Point-Of-Use Water Treatment In Developing Countries: Principles, Challenges And Opportunities, Haiyan Yang, Shangping Xu, Derek E. Chitwood, Yin Wang

Faculty Work Comprehensive List

Drinking water source contamination poses a great threat to human health in developing countries. Point-of-use (POU) water treatment techniques, which improve drinking water quality at the household level, offer an affordable and convenient way to obtain safe drinking water and thus can reduce the outbreaks of waterborne diseases. Ceramic water filters (CWFs), fabricated from locally sourced materials and manufactured by local labor, are one of the most socially acceptable POU water treatment technologies because of their effectiveness, low-cost and ease of use. This review concisely summarizes the critical factors that influence the performance of CWFs, including (1) CWF manufacturing process …


Stream Restoration As A Method Of Improving Local Water Quality, Emily George Apr 2020

Stream Restoration As A Method Of Improving Local Water Quality, Emily George

Environmental Studies Senior Seminar Projects

Projects of stream restoration are a known Best Management Practice (BMP) to approach stormwater management, and have been adopted globally as a means of improving local hydrology. Urbanization has led to an increase in impervious surfaces, resulting in deteriorated streams, many of which are subject to stream restoration. Stormwater control measures (SCM), such as stream restoration, are considered to be a subset of green infrastructure as a method to reconnect streams with surrounding riparian areas, revitalize original hydrology, and support the local ecosystems. This paper looks into the viability of stream restoration as a way of improving water quality, focusing …


Cost Benefit Analysis And Beyond: Stream Restoration In Richmond, Virginia, Claire Powell Apr 2020

Cost Benefit Analysis And Beyond: Stream Restoration In Richmond, Virginia, Claire Powell

Environmental Studies Senior Seminar Projects

This research assessed the costs and benefits of six recent stream restoration projects in Richmond, Virginia within the context of the Chesapeake Bay Total Maximum Daily Load (CB TMDL) pollutant reduction requirements. In order to meet these requirements, state and local governments promoted stream restoration as an important way to reduce Bay-wide inputs of nitrogen, phosphorus, and total suspended solids. The overall intention of this paper was to holistically evaluate the risks and positive impacts associated with stream restoration, with a focus on Little Westham Creek, a stream restoration project located on the University of Richmond campus. I hypothesized that …


The North Wyke Farm Platform: A New Uk National Capability For Research Into Sustainability Of Agricultural Temperate Grassland Management, Phil J. Murray, Bruce A. Griffith, Robert J. Orr, Martin S. A. Blackwell, Jane M. B. Hawkins, S. Peukert Apr 2020

The North Wyke Farm Platform: A New Uk National Capability For Research Into Sustainability Of Agricultural Temperate Grassland Management, Phil J. Murray, Bruce A. Griffith, Robert J. Orr, Martin S. A. Blackwell, Jane M. B. Hawkins, S. Peukert

IGC Proceedings (1997-2023)

The North Wyke Farm Platform is a new UK National Capability that will enable studies that can be closely monitored and controlled under different land-use options at the farm-scale. As a Biotechnology and Biological Sciences Research Council-funded National Capability, the Farm Platform provides centralised scientific facilities including core data (field and water chemistry, water flow rates, greenhouse gas emissions from soils, livestock and agronomic data, and farm management records). Access to the Farm Platform for experimental work or to data will be available to other research users and collaborators. This shared approach will enhance the depth and breadth of information …


Mediating Socio-Political Barriers To Water Quality Improvement In Surface Water On Grazed Wildlands, Tipton D. Hudson Apr 2020

Mediating Socio-Political Barriers To Water Quality Improvement In Surface Water On Grazed Wildlands, Tipton D. Hudson

IGC Proceedings (1997-2023)

Acute and growing social and legal conflict over regulation of non-point source pollution in Washington State has hampered proactive efforts to improve water quality in streams dominated by grazed watersheds. Livestock farmers caught in the conflict over water quality experience legal risk, reduced quality of life, and financial risk. Nonpoint source pollution is “pollution that is not released through pipes but rather originates from multiple sources over a relatively large area”. This diffuse pollution is notoriously difficult to regulate. Because causality is often not definable, coercing behavior is problematic, and most efforts to address nonpoint source (NPS) pollution rely on …


Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen Apr 2020

Physical And Biological Factors Controlling The Fate Of Nitrate In A Louisiana Coastal Deltaic Floodplain, Alexandra Christensen

LSU Doctoral Dissertations

The Mississippi River Delta is threatened by a growing pressure to support large human populations in the United States both with food production, navigation systems, and urban development in the Mississippi River Basin. Nitrate-nitrogen load in the Mississippi River, up to 100 Tg N yr-1 from agricultural and urban runoff, leads to phytoplankton blooms and hypoxia across the Louisiana continental shelf, creating dead zones of low dissolved oxygen threatening a significant commercial fishery. Along the coast and river corridors, floodplain ecosystems have the capacity to retain and remove nitrate. This dissertation explores the role of productive, actively growing coastal …


Protecting Water Quality In Virginia: Recommendations To Combat Sea Level Rise And Increased Storm Events, Madhavi Kulkarni Apr 2020

Protecting Water Quality In Virginia: Recommendations To Combat Sea Level Rise And Increased Storm Events, Madhavi Kulkarni

Virginia Coastal Policy Center

Impairment of Virginia waters is tied to coastal storm hazards and sea level rise because excess floodwaters are contaminated by flood-exposed industrial and residential facilities, and these toxic floodwaters flow into the state’s water bodies. In Virginia, thousands of industrial facilities can potentially be subjected to the effects of stormwater flooding, hurricane storm surge, and sea level rise, in turn affecting water quality. Failing or unmaintained septic systems also pose a major threat to the quality of Virginia waters that increases with recurrent inundation by flood waters. A combination of changes to law and policy and investment in infrastructure are …


Senior Project: An Investigative Study Into The Bacterial Contamination Of Little Black Creek, Margaret I. Brenneman Apr 2020

Senior Project: An Investigative Study Into The Bacterial Contamination Of Little Black Creek, Margaret I. Brenneman

Honors Projects

An investigation of Escherichia coli concentrations in a west Michigan stream was conducted to determine sources of fecal contamination that impact water quality. Little Black Creek (LBC) is located in Muskegon County and discharges into Lake Michigan at the P.J. Hoffmaster Campground Beach. Often referred to as an “indicator bacteria,” water contaminated with E. coli has a high probability to contain other enteric pathogens as well. Beach water testing in 2020 using Colilert-18 methods revealed E. coli levels of 579 cfu/100mL in the creek discharge area that exceeded total body contact criteria of 300 cfu/100mL. A follow-up study of the …


Designing A Smart Internet Of Things Solution For Point Of Use Water Filtration Management System In Residential, Commercial And Public Settings, Tristan Lim, Hwee-Pink Tan, Chin Sin Ong, Rahul Belani, Siddhant S. K. Agrawal Apr 2020

Designing A Smart Internet Of Things Solution For Point Of Use Water Filtration Management System In Residential, Commercial And Public Settings, Tristan Lim, Hwee-Pink Tan, Chin Sin Ong, Rahul Belani, Siddhant S. K. Agrawal

Research Collection School Of Computing and Information Systems

The use of water filtration Point-of-Use (POU) systems are extensive, ranging from water dispensers in public estates, to household POU water systems. Manufacturers typically recommend filtration cartridges to be changed (i) after their useful life, or (ii) when the water flow volume have exceeded certain capacity, whichever is earlier. However, filtration mechanisms are typically not changed with sufficient regularity. Overused filters can result in negative health effects, over and above the deterioration and loss of filtration benefits of the POU water system. Presently most existing water purification systems do not have smart connected Internet of Things (IoT) means of informing …


Rehabilitating Degraded Frontage Soils In Tropical North Queensland, Trevor J. Hall Feb 2020

Rehabilitating Degraded Frontage Soils In Tropical North Queensland, Trevor J. Hall

IGC Proceedings (1997-2023)

The extensive tropical grasslands of north Queensland are grazed by beef cattle and provide a significant proportion of the water flowing into the Great Barrier Reef (GBR) lagoon. Soil sediments and nutrients eroding from the grazing lands of the Burdekin and Fitzroy catchments in north-east Queensland contributes to reduced water quality in the GBR lagoon. Degraded and eroded D-condition bare areas and eroding gullies in grazing lands provide a disproportionate amount of soil and nutrient losses from predominately native pasture grasslands used for cattle grazing. Rehabilitating these degraded areas will help improve water quality flowing onto the reef.

Rehabilitation methods …


Surface Water Nitrogen Attenuation From The Accomack County, Va Southern Landfill Groundwater Discharge, Richard A. Snyder, Paige G. Ross Feb 2020

Surface Water Nitrogen Attenuation From The Accomack County, Va Southern Landfill Groundwater Discharge, Richard A. Snyder, Paige G. Ross

Reports

Previous sampling of the stream crossing Bobtown Road (Rt 178) near the intersection of Hollies Church Road (Rt. 620), had indicated high levels of nitrogen in the stream flow (Snyder and Ross, 2019a). The proximity of the retired Accomack County Landfill upstream of the site triggered a higher resolution sampling of the stream in an attempt to isolate a source of the nitrogen loading (Snyder and Ross, 2019b). Accomack County has requested repeated sampling of this stream segment to monitor nutrient attenuation trends from the site, and stations were established for that purpose. This is the first report of that …


Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray Feb 2020

Risk And Cost Assessment Of Nitrate Contamination In Domestic Wells, Pongpun Juntakut, Erin M.K. Haacker, Daniel D. Snow, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

This study combines empirical predictive and economics models to estimate the cost of remediation for domestic wells exceeding suggested treatment thresholds for nitrates. A multiple logistic regression model predicted the probability of well contamination by nitrate, and a life cycle costing methodology was used to estimate costs of nitrate contamination in groundwater in two areas of Nebraska. In south-central Nebraska, 37% of wells were estimated to be at risk of exceeding a threshold of 7.5 mg/L as N, and 17% were at risk of exceeding 10 mg/L as N, the legal limit for human consumption in the United States. In …


Water Quality In Accomack County Freshwater Streams, Richard A. Snyder, Paige G. Ross Jan 2020

Water Quality In Accomack County Freshwater Streams, Richard A. Snyder, Paige G. Ross

Reports

Expansion of poultry house operations and use of litter as a soil amendment in Accomack County Virginia has raised concerns for water quality impacts both seaside and bayside of the Eastern Shore of Virginia (ESVA). This ongoing investigation is examining freshwater stream water quality in Accomack Virginia to identify water quality impairments from poultry operation storm water runoff. Sampling in 2019 followed two inch rainfall events covering 83 streams at road crossings in southern and northern Accomack County. Estimates of land cover in the drainages for these streams were used to determine correlations between stream water nutrient levels and the …


Swine Slurry Characteristics As Affected By Selected Additives And Disinfectants, Jon Duerschner, Shannon L. Bartelt-Hunt, Kent Eskridge, John E. Gilley, Xu Li, Amy M. Schmidt, Daniel D. Snow Jan 2020

Swine Slurry Characteristics As Affected By Selected Additives And Disinfectants, Jon Duerschner, Shannon L. Bartelt-Hunt, Kent Eskridge, John E. Gilley, Xu Li, Amy M. Schmidt, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Current swine industry practice is to house animals in confinement facilities which capture and store feces and urine as slurry in pits below the production area. Additives and disinfectants may be introduced into the manure pits. This study was conducted to measure the effects of additives and disinfectants on temporal changes in swine slurry characteristics. Slurry from a commercial swine production facility in southeast Nebraska, USA was collected and transferred to 57 L reactors located within a greenhouse. Selected additives and disinfectants were added to the reactors and physical properties, chemical characteristics, and antibiotic concentrations were monitored for 40 days. …


Evaluating Water Quality Regulation As A Driver Of Farmer Behavior: A Social-Ecological Systems Approach, Courtney R.Hammond Wagner, Suzie Greenhalgh, Meredith T. Niles, Asim Zia, William B. Bowden Jan 2020

Evaluating Water Quality Regulation As A Driver Of Farmer Behavior: A Social-Ecological Systems Approach, Courtney R.Hammond Wagner, Suzie Greenhalgh, Meredith T. Niles, Asim Zia, William B. Bowden

College of Agriculture and Life Sciences Faculty Publications

Water quality policy for agricultural lands seeks to improve water quality by changing farmer behavior. We investigate farmer behavior in three water quality regimes that differ by rule structure to examine the fit and interplay of each policy within its social-ecological context, important aspects for improving water quality. Vermont, USA’s practice-based policy requires the adoption of specific practices, whereas New Zealand’s Lake Taupo and Lake Rotorua performance-based policies require farmers to meet a numeric limit for nutrient loss on their farm. Across the three regions we interviewed 38 farmers to elicit mental models of nutrient management changes. We utilized the …


Riverine Biota As Environmental Indicators Of Artisanal Small-Scale And Large-Scale Gold Mining Impacts On Riverine Ecosystems In Brong Ahafo Region, Ghana, K. F. Macdonald, M. Lund, E. Van Etten Jan 2020

Riverine Biota As Environmental Indicators Of Artisanal Small-Scale And Large-Scale Gold Mining Impacts On Riverine Ecosystems In Brong Ahafo Region, Ghana, K. F. Macdonald, M. Lund, E. Van Etten

Research outputs 2014 to 2021

A study on two adjacent small ephemeral river systems in the upper Tano River Basin in Brong Ahafo, Ghana; one impacted by ASGM and the other by a modern large gold mining (LSM), showed that impacts of mining on river sediment and water quality and quantity were reflected in the macroinvertebrate and microbial communities. This study investigated the impacts of ASGM on the ecology of the Surow River and that of a large-scale mining (LSM, the Ahafo mine) on the Subri River between February 2013 and April 2014 Macroinvertebrate communities responded to the shift in river water and sediment qualities, …


Evaluation Of The Relationship Between Land Use And Water Quality In Kittitas County, Wa, Lindsay Schulz Jan 2020

Evaluation Of The Relationship Between Land Use And Water Quality In Kittitas County, Wa, Lindsay Schulz

All Master's Theses

Water in Kittitas County is extremely valuable since it supports farming, recreation, and cultural activities, as well as environmental processes and a diversity of biological life while providing many ecosystem services. However, land conversions required by agricultural and urban land uses can negatively impact water quality and the biological function of the stream. I studied how forested, agricultural, and urban land use affect six streams. Fourteen sites were sampled, once each in July, August, and September 2019. Land use was calculated as a percentage of forested, agricultural, and urban land use within a 100-m buffer of the stream, upstream of …