Turbidity In The Aquatic Environment

This literature review of the effects of turbidity and suspended material in aquatic environments covers the following subjects: definitions, units of measure, and methods of measurement; origins; and effects in aquatic environments. Turbidity, regardless of the multiplicity of definitions, units of measure, and methods of measurement, is an expression of the optical properties of water that cause light to be scattered and absorbed rather than transmitted in a straight line. Turbidity is not the same as siltation, although the terms have been used synonymously in the past. The various units of measure include the Jackson Turbidity UNIT (JTU), Formazin Turbidity Unit (FTU), and Nephelometric Turbidity Unit (NTU). The methods of measuring percent transmission or the weight per volume concentration of suspended particulates are based on either gravimetric or optical techniques.

The impacts of siltation and suspended sediments on water quality and resident aquatic organisms is one of the most common problems facing resource managers today. Most construction activities in or near a watercourse have the potential to result in decreased shoreline stability and/or an increase in siltation, suspended sediments and turbidity. This annotated biliography was prepared in response to requests from seveal Ontario Ministry of Natural Resources biologists and technicians in the Southern Region. The author attempted to assemble and summarize reference material on various aspects of this topic including sources of suspended solids, physical/chemical processes, impacts to water quality and aquatic life, and remediations. This bibliography is intended to prove a consolidation and synthesis of information which is readily available for day-to-day use by field staff. Almost 1200 references are cited.

The purpose of this book is to give an introduction to the most important aspects of suspended matter in the aquatic environment: its origin and composition, the concentration distribution, transport and deposition, and the most important physical-chemical-bio logical process that affects suspended matter: flocculation. In Chap ter 1 the development of suspended matter observation and study throughout history is given, with the coming of a more modern approach during the 19th century and the first half of the 20th century, and the development of the present science of suspended matter after 1945. The sources of suspended matter in rivers, lakes, estuaries, and the sea are discussed in Chapter 2, which includes the supply of detrital particles as well as the formation of new particles in the water (organic matter, carbonate, opal). The concentration distribution of suspended matter in rivers, lakes, estuaries, tidal is discussed in Chapter 3, to which is areas, lagoons, and in the sea added a discussion on the sampling of suspended matter and on methods to determine its concentration. Particle composition is treated in Chapter 4, to which is added a section (4. 6) on the compositional analysis of suspended particles. Also included is a discussion on particle surface characteristics and the adsorption of elements and compounds onto particles.

This document is intended to provide an overview of the major components of surface and ground water quality and how these relate to ecosystem and human health. Local, regional and global assessments of water quality monitoring data are used to illustrate key features of aquatic environments, and to demonstrate how human activities on the landscape can influence water quality in both positive and negative ways. Clear and concise background knowledge on water quality can serve to support other water assessments.