Chapter 4 Habitats
depths and widths; and stable banks with good tree canopy and a medium-to-wide riparian zone with few (if any) breaks (NCDEQ 2011) . Species diversity is potentially greatest in large streams and medium-sized rivers, especially in riffle and run habitats. • Poor in-stream habitats will generally have primarily sandy, unconsolidated substrates, an absence of riffles; narrow and sparsely vegetated riparian zones with breaks; and deeply entrenched channels with unstable, vertical, and sparsely vegetated banks (NCDEQ 2011) . 4.2.1 Problems Affecting Aquatic Communities There are numerous threats that can affect a broad range of aquatic natural systems and some of the most common and widely occurring are described in this section. The most pervasive impact to fish and wildlife is the loss of habitat. There are numerous sources of impacts or events that ultimately result in the loss of habitat. Examples of these sources are provided below. The natural community descriptions provided in this chapter provide information about the problems that affect specific community types. Additional information about specific categories of threats likely to impact SGCN and habitats is provided in Chapter 5 Threats. Wastewater Discharges . Point source discharges from industrial or municipal effluent can be a source of contamination to aquatic systems. These potential sources of water pollution are subject to the National Pollutant Discharge Elimination System (NPDES) permit requirements designed to address numerous types of pollutants associated with specific industry types and subject to US Environmental Protection Agency (USEPA) regulation. For example, effluents associated with sewage treatment can affect 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 penetration, 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 affect the solubility of dissolved chemicals and adsorption of certain metals, which can result in toxicity and lethal water conditions for aquatic organisms (McDaniel 1993) . Emerging contaminants in wastewater effluent such as pharmaceuticals, endocrine-disrupting compounds (EDCs), cosmetics, and other personal care products have become a source of concern for adverse health impacts to aquatic life (see “Pollution” below). Thermal Discharges . Discharge waters with temperatures that are a few degrees different from receiving waters can cause changes to the metabolic activity, behavior, and physiological conditions of aquatic species. Growth rates are impacted by increased temperatures, and life history synchrony (reproduction or emergence) might be affected where there are thermal discharges (McDaniel 1993) .
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2025 NC Wildlife Action Plan
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