Optical water quality and human perceptions of rivers: an ethnohydrology study

Abstract

Rivers are revered worldwide for their ecologic, scenic, and recreational value. The capacity to communicate effectively among human groups with vested interest in rivers hinges on understanding the nature of human perceptions of water quality and the extent to which they vary intraculturally. Recognizing the intersection between measured water quality and the characteristics of rivers that influence human perceptions facilitates potential for better communication across disciplines and among stakeholders. We conducted interviews and a pile‐sort task with water quality experts and nonexperts. Our analysis suggested human evaluation of water quality is guided by culturally constructed criteria, regardless of respondent expertise, experience, or demographics. Cluster analysis results implied that measured physical and chemical parameters of rivers were directly related to the visible attributes used in human judgments. We suggest that, regardless of variability among individual stakeholders, observable characteristics may be the foundation for a common understanding of water quality in rivers.

Colour Classification of 1486 Lakes across a Wide Range of Optical Water Types

“…This provides an opportunity for efficient monitoring using stationary or remote radiometers, as well as for community involvement in science, e.g., through the measurement of colour by smartphone cameras [62]. In addition, the perceived colour has been directly linked to recreational use and the desirability of freshwater systems [2,3] affecting the social and economic value of lakes and rivers [63]. This makes perceived colour a useful measurement in the context of optical water quality [1,4] and led to its recent inclusion in the New Zealand national environmental monitoring standards for lakes [64].…”

“…The colour of water as perceived by a human observer is intuitively associated with its suitability for consumption, quality of food collection, fitness for recreation, and aesthetic value, making it arguably one of the oldest water-quality attributes [1][2][3]. Water colour is integral to the concept of optical water quality, which may be defined as "the extent to which the suitability of water for its functional role in the biosphere or the human environment is determined by its optical properties" [4].…”

Water clarity measures as indicators of recreational benefits provided by U.S. lakes: Swimming and aesthetics

“…From stream data in Smith et al (2015) we interpolated a threshold between high and low benefit quality of 3.4 NTU for New York, USA. From Arkansas, USA river data in West et al (2016) we interpolated a threshold between high and low benefit quality of about 10 NTUs. These values are higher (less protective) than the thresholds we derived for lakes in the Mountains ecoregion (<1.5, Fig.…”

Black disk visibility, turbidity, and total suspended solids in rivers: A comparative evaluation

“…Visual features are the dominant influence on human perceptions of water quality (David 1971). Visual water clarity serves the mental processes that influence human perceptions of water quality in the environment (West et al 2016b). Visual water clarity relates to the perceived health of the system (Harmsworth et al 2011), issues of safety (Smith et al 1995), and even morality (Coughlin 1976).…”

“…In river monitoring, the quantity of interest is often the concentration of particulate matter in suspension. Effects of suspended sediment on OWQ are relevant to ecosystem health and human perceptions (Davies‐Colley et al ; Smith and Davies‐Colley ; West et al ). Suspended sediments have come to be of primary interest in rivers around the world as watersheds are increasingly subject to disturbances by agriculture, urbanization, mining, and logging.…”