4.2 Aquatic Communities
Common names are used throughout this document for all species discussions except those animals for which there is taxonomic uncertainty; in those few instances the scien- tifc name is used to identify the species. Appendix E provides a list of common and scien- tifc species names for invasive and nonnative species. Appendix G provides common and scientifc names for SGCN and priority species. 4.2.1 Problems Affecting Aquatic Communities Tere are numerous threats that can afect a broad range of aquatic natural systems and some of the most common and widely occurring are described in this section. Te natural community descriptions provided in this Chapter provide information about the problems that afect specifc community types. Additional information about threats likely to impact wildlife and habitats is provided in Chapter 5. Wastewater Discharges . Point source discharges from industrial or municipal efuent can be a source of contamination to aquatic systems. Tese potential sources of water pollu- tion are subject to the National Pollutant Discharge Elimination System (NPDES) permit requirements designed to address numerous types of pollutants associated with specifc industry types and subject to US Environmental Protection Agency (EPA) regulation. For example, efuents associated with sewage treatment can afect the pH of receiving waters and be a source of suspended solids, biological oxygen demand, ammonia, phosphates, and chlorine. Suspended solids in discharges can increase turbidity that reduces light pen- etration, absorbs metals and organic materials in the water column, and concentrates them into sediment when they settle on the bottom substrate. High levels of total dissolved solids in the discharges can add salts to receiving waters. Acidic or alkaline wastes can change the pH of receiving waters and afect the solubility of dissolved chemicals and adsorp- tion of certain metals, which can result in toxicity and lethal water conditions for aquatic organisms (McDaniel 1993) . Emerging contaminants in wastewater efuent such as pharma- ceuticals, endocrine-distrupting compounds (EDCs), cosmetics, and other personal care products have become a source of concern for adverse health impacts to aquatic life (see “Pollution” below). Termal Discharges. Discharge waters with temperatures that are a few degrees diferent from receiving waters can cause changes to the metabolic activity, behavior, and physiolog- ical conditions of aquatic species. Growth rates are impacted by increased temperatures, and life history synchrony (reproduction or emergence) might be afected where there are thermal discharges (McDaniel 1993) . Petroleum Spills. Waterborne spills of petroleum products such as oil and grease can impact receiving waters by interfering with gaseous exchange and coating substrates with sludge and smothering organisms. Oil and grease can coat respiratory structures of fsh
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2015 NC Wildlife Action Plan
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