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Angela Harris

Asst Professor

Mann Hall 208

Publications

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Grants

Date: 01/01/23 - 12/31/25
Amount: $193,773.00
Funding Agencies: NC Department of Justice (NCDOJ)

Project Summary: Effective riparian vegetative buffers and wetlands are carbon sinks, minimize nutrient input, soil erosion and related runoff into adjacent surface waters. They are an essential component of livestock environmental resource management and mitigate the movement of nitrogenous and fecal waste from livestock operations and manure management fields into waterways. Watersheds in the coastal plain of North Carolina include a mixture of homes, businesses, livestock operations and other forms of agriculture. Each is a potential source of nutrient and fecal waste in surface waters. Watershed contamination with nutrients or fecal waste are traditionally considered to be non-point sources of contamination. However, all fecal waste has a vertebrate animal origin, and the species of origin varies with adjacent land-use practices. All vertebrates release cells from their gastrointestinal tract in their feces. These cells contain mitochondrial DNA (mtDNA), a routine aspect of forensic investigation that can be applied to identify the animal hosts associated with fecal waste. An mtDNA-based assay we have developed can now specifically attribute the source of fecal waste to humans, livestock (cattle, pigs, poultry, goats), companion animals (dog, cat) and wildlife (white-tailed deer and Canada goose). We propose a comprehensive cross-sectional study to identify locations contaminated by nitrate and fecal waste in mixed use livestock intensive areas of the lower Neuse and Cape Fear watersheds. The study will be conducted with the aim of identifying the presence of fecal contamination and attributing the source of fecal contamination to their species of origin. Water grab samples will be screened for Enterococcus spp. as an indicator of fecal contamination. Samples from positive locations will then be tested for vertebrate mtDNA to attribute the contamination to specific species. Additional sampling at positive sites will assess fecal waste input during storm events. Riparian areas adjacent to waterways testing positive will be visualized using satellite imagery to identify proximity to potential sources of contamination with the identified species. Samples will be assessed for the potential correlation of fecal sources with ammonium, nitrate, chloride, silicate, phosphate, dissolved organic nitrogen and dissolved organic nitrogen. We will conduct community design charettes with cooperating town environmental management personnel and residents, in cooperation with local extension agents and resource managers to identify opportunities for riparian vegetative buffer or wetlands enhancement. Specific objectives include: 1) Identifying locations in agricultural livestock intensive areas where water quality is being degraded by nitrogenous and fecal waste; 2) Identifying riparian locations that will benefit from buffer or wetlands development or refinement; and 3) Working with community stakeholders to develop a plan for buffer and wetland development or refinement. The studies reflect the ecosystem health-oriented objectives of the Environmental Enhancement Grant (EEG) program by facilitating efforts to identify locations that would benefit from either the introduction of vegetative buffers or wetlands or the potential refinement or restoration of existing buffers or wetlands.

Date: 03/04/22 - 3/04/25
Amount: $290,783.00
Funding Agencies: US Army - Corps of Engineers

The ability to continuously monitor fecal bacteria concentrations in nearshore waters through field sensing has the potential to transform the way in which bacteria-driven public health risks are anticipated, mitigated, and managed by allowing for near real-time detection and the creation of high-quality datasets from which forecast models can be developed. Advances in freshwater monitoring reveal that fecal contamination can be predicted using data collected via high-frequency water quality sondes, but additional research is needed to extend these frameworks to coastal waters. We propose to observe water quality conditions every 15 minutes in Bald Head Creek, North Carolina, a tributary of the Cape Fear River, using a multiparameter sonde (YSI EXO2). The sonde will include sensors to monitor conductivity, temperature, dissolved oxygen, pH, turbidity, total algae (phycocyanin, phycoerythrin, and chlorophyll), fluorescent dissolved organic matter, tryptophan-like fluorescence, and water depth. In addition to observing water quality variables, we will analyze creek water samples for fecal indicator bacteria, antibiotic resistant bacteria, amino acids, and particulate and dissolved organic carbon isotopic signatures across four intensive field campaigns. Data collected via this project will be used to develop an innovative observation and machine learning modeling framework for predicting fecal contamination at high frequencies. Insights gained through the project will be shared with local and federal partners (e.g., Village of Bald Head Island, NC Coastal Federation, FDA Division of Seafood Science).

Date: 09/01/21 - 8/31/23
Amount: $120,000.00
Funding Agencies: NCSU Water Resources Research Institute

The Great Coharie River (AKA Great Coharie Creek) is a culturally and environmentally significant water body in Eastern North Carolina. The river has exhibited elevated levels of nutrients and microbial contamination, even after extreme flooding events, and community groups, particularly the Coharie Tribe, are eager to develop a more nuanced understanding of the temporal and spatial dynamics of contamination in the river to ensure human safety during cultural and recreational activities on the river. We propose to conduct high temporal resolution sampling at 4 sites along the river during different seasons and rainfall conditions. Water samples will be analyzed for nutrients, E. coli (fecal indicator bacteria) and source-specific molecular markers of fecal contamination (e.g., human, swine, and poultry). Forecast models will be develop to predict contamination with environmental covariates (e.g., temperature, rainfall, discharge). Working with Coharie Tribe leaders and other community members and applying insights from this research, we will support the development of long-term monitoring plans and decision-making tools for protecting and using the river.

Date: 09/01/20 - 8/31/23
Amount: $414,884.00
Funding Agencies: National Science Foundation (NSF)

Floods impact a series of interconnected urban systems (referred to in this project as the Urban Multiplex) that include the power grid and transportation networks, surface water and groundwater, sewerage and drinking water systems, inland navigation and dams, and other system, all of which are intertwined with the socioeconomic and public health sectors. This project uses a convergent approach to integrate these multiple interconnected systems and merges state-of-the-art practices in hydrologic and hydraulic engineering; systems analysis, optimization and control; machine learning, data and computer science; epidemiology; socioeconomics; and transportation and electrical engineering to develop an Urban Flood Open Knowledge Network (UF-OKN). The UF-OKN will be built by bringing together academic and non-academic researchers from engineering, computer science, social science, and economics. The UF-OKN is envisioned to empower decision makers and the general public by providing information not just on how much flooding may occur from a future event, but also to show the cascading impact of a flood event on natural and engineered infrastructure of an urban area, so that more effective planning and decision-making can occur.

Date: 01/23/23 - 7/31/23
Amount: $9,999.00
Funding Agencies: NCSU Sea Grant Program

Microbiological contaminants will be screened in floodwaters during high tide floods in Beaufort and Carolina Beach, NC.

Date: 08/01/22 - 7/31/23
Amount: $364,361.00
Funding Agencies: NC Department of Health & Human Services (DHHS)

The purpose of this contract is to conduct SARS-CoV-2 variant quantification and sequence analysis on wastewater samples collected twice a week throughout the state of North Carolina as part of NCWMN. Results will be shared weekly with NCDHHS for submission to CDC NWSS. Additionally, these results will supplement other COVID-19 surveillance strategies for NCDHHS and be shared with academic partners of the NC WW Path for further development of predictive models and spatial applications for public health surveillance.

Date: 07/01/22 - 6/30/23
Amount: $120,000.00
Funding Agencies: NC Department of Health & Human Services (DHHS)

North Carolina (NC) has launched the NC Wastewater Monitoring Network as part of the Centers for Disease Control and Prevention (CDC) National Wastewater Surveillance System (NWSS). This system provides information on the presence and persistence of SARS-CoV-2-like viruses in wastewater systems as a metric of community COVID-19 prevalence. This approach provides a relatively low-cost way to measure both symptomatic and asymptomatic COVID-19 infections in a community-wide sample. Wastewater surveillance can demonstrate trends in COVID-19 prevalence, direct action to protect public health, and allay concerns about the burden of disease when SARS-CoV-2 concentrations are low. The NC Wastewater Monitoring Network builds on an existing collaboration between NCDHHS and the NC Wastewater Pathogen Research Network (NC WW PATH) led by Dr. Rachel Noble in collaboration with University of North Carolina (UNC) system researchers including those from North Carolina State University, UNC Chapel Hill, UNC Charlotte, UNC Wilmington, and East Carolina University. NC WW PATH has developed laboratory methods for measuring the SARS- CoV-2 virus in samples from wastewater treatment plant influent wastewater and primary solids and completed weekly sampling at 20 wastewater treatment plants representative of urban, semi-urban, and rural wastewater sources across nine counties in 2020. NC WW PATH continues to compare wastewater and solids concentrations with data from NCDHHS and other community prevalence studies while applying epidemiological and geospatial tools to develop statewide interactive mapping to better inform public health decisions.

Date: 07/01/21 - 6/30/23
Amount: $750,000.00
Funding Agencies: US Dept. of Health & Human Services (DHHS)

The project is to support the state of North Carolina in surveillance of SARS-CoV-2 variants in the population. We will sequence SARS-CoV-2 from clinical specimens collected as part of the NCSU surveillance lab (surveillance lab director Megan Jacob is a co-PI) and partner WakeMed hospitals. We estimate to sequence 3700 samples over the course of the project.

Date: 08/16/21 - 6/30/23
Amount: $1,224,462.00
Funding Agencies: US Dept. of Treasury

TSA: Environmental Surveillance of Microbial Contaminants

Date: 10/01/21 - 6/30/23
Amount: $57,000.00
Funding Agencies: National Pork Board

Livestock operations generate fecal waste and manure management is an essential aspect of livestock production. Local and state regulations mandate permitting, training, design specifications, and stream vegetation buffers between livestock operations and surface waters. The scale of pork production has increased to meet consumer demand and as production facilities have grown, communities have heightened their concern about the environmental impact of pork operations. Pork producers have worked effectively to reduce their overall water usage, land use, and the carbon footprint of farming operations (National Pork Board, 2018, Thoma et al. 2011). Responsible environmental farm management has become a business necessity for pork producers in the US and producers have affirmed their obligation to manage pork production operations in a manner that protects natural ecosystems and public health. Watersheds, however, generally support multiple types of livestock operations and human dwellings. Each livestock enterprise and residential community is a potential source of fecal waste in surface waters. Fecal waste in surface waters is generally referred to as non-point source contamination. In reality, all fecal waste has a vertebrate animal origin and the species of origin varies with adjacent land-use practices. Monitoring programs established to protect public health have traditionally relied on the culture or detection of fecal coliforms, total coliforms or Enterococcus bacteria in water samples as indicators of fecal contamination in surface waters. These enteric organisms are non-specific indicators of the presence of fecal waste but do not attribute contamination to specific animal hosts. The detection of host-specific enteric organisms, such as Bacteroidales spp. and genetic assays focused on detecting these microbial species have been developed as alternatives to non-host specific indicator organism detection methods (Harwood et al. 2009). All vertebrates release cells from their gastrointestinal tract in their feces. These cells contain mitochondrial DNA (mtDNA), a routine aspect of forensic investigation that can be applied to identify the animal hosts associated with fecal waste (Caldwell et al. 2007). The detection of mtDNA is highly host specific. If mtDNA is detected in a water sample, the vertebrate animal associated with that mtDNA can be determined. Initial studies, however, lacked sensitivity (Caldwell et al. 2009). When we initially developed and tested these assays, at times, fecal waste was present in a stream but not detected. In studies supported by the National Pork Board, we refined these initial mtDNA assays by adapting the use of new Droplet digital PCR technology (BioRad Inc., California, USA), which markedly enhanced the sensitivity of the assay for identifying the presence of host mtDNA in surface waters. New primers and probes were designed, and the assay proved both sensitive and specific. Our studies confirmed the presence of fecal contamination in Stockinghead Creek in Duplin County, NC and documented that the fecal contamination in the creek originates from at least four species, cattle, humans, poultry and swine. This proposal focuses on addressing concerns about the origin of fecal waste in surface waters in other North Carolina livestock intensive watersheds. Specific objectives include: 1) Attributing the source of fecal contamination in NC surface waters in Duplin and Sampson County, NC watersheds ; and 2) Responding to concerns about fecal contamination.


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