Rivers assessment systems

This would allow a more comprehensive ecological risk assessment, and also predict a perspective of the geoecological situation changes, in particularly, in the Northern Caspian under varying input of different pollutants into the river-sea system. 

Modjeski and Masters. 2009. Vessel Collision Risk Assessment of Bridges Over The McCleUan-Kerr Arkansas River Navigation System With Respect to Loaded Runaway Barges , Report prepared for Oklahoma Department of Transportation, Mechanicsburg, PA. 

The basis for assessment of river quality is valid data, but the question of data validity is secondary to the fundamental question What is the purpose of the river quality assessment activity What questions are being asked In short the means are determined by the ends. If, for example, the intent of an assessment program is to ascertain compliance with law, then a fixed interval "grab sampling program could be established at various river system sites selected on the basis of established guidelines which are consistent with the... 

Kammerbauer J, Moncada J. 1998. Pesticide residue assessment in three selected agricultural production systems in the Choluteca River Basin of Honduras. Environ Pollut 103 171-181. 

Martin JM, Nijampurkar V, Salvation F (1978b) Uranium anti Thorium isotope behavior in estuarine systems. In Biogeochemistry of estuarine sediments. UNESCO, p 111-127 Mathieu D, Bemat M, Nahon D (1995) Short-lived U and Th isotope distribution in a tropical laterite derived from Granite (Pitinga river basin, Amazoitia, Brazil) application to assessment of weathering rate. Earth Planet Sci Lett 136 703-714... 

There are many models for assessing risks to human health and/or the environment. Some of them are multimedia models, which assess the exposure and risks in different environmental matrices, such as soil, air, water, and food chains with different degrees of complexity within each medium. Conversely, others are more specific with regard to a medium or a system (e.g., river or food chain). Other models assess only human health risks or environmental risks, while some assess both risks. Based on the type of scenario that is studied, an appropriate model will be chosen. 

Structure and function need to be jointly considered in the assessment of effects of stressors on river systems. It has been shown that the two sets of parameters offer complementary information since they cover different time scales and responses. This being shown in the case of biofilms is not a unique characteristic of them, but it might be applied to all other biological communities (e.g. macroinvertebrates, fish). These differ from the biofilm in its higher size and life span, and therefore in their integrative capacity to reflect effects in one part of the ecosystem. Higher traffic levels in addition to biofilms should be considered to study the whole ecosystem. In all of these biological compartments, the combined use of descriptors may amplify our ability to predict the effect of stressors on river basins. 

Next plans should more reflect the understanding of the interactions and dependencies of the aquatic and land systems with their individual drivers and pressures (e.g. increased irrigation and change in land use). By achieving this, they will be prepared to better prioritise measures to be taken, assess their effectiveness and to take into account the impact of potential future scenarios within the river basins. 

Menconi, M. and A. Paul. 1994. Hazard Assessment of the Insecticide Chlorpyrifos to Aquatic Organisms in the Sacramento-San Joaquin River System. Calif. Dept. Fish Game, Environ. Serv. Div., Admin. Rep. 94-1. 74 pp. 

Atmospheric contaminants from smelting works or combustion processes eventually enter the natural drainage system as fall out, and are carried into the rivers. It is probable that the deposition of sediments and the higher pH of marine water, which leads to precipitation, results in a build-up of the heavy metal pollutants in the river estuary. An assessment of this build-up is essentially an analytical problem. 

Zhao JL, Ying GG, Liu YS, Chen F, Yang JF, Wang L, Yang XB, Stauber JL, Wame MSt J (2010) Occurrence and screening level risk assessment of human pharmaceutical in the Pearl River system, South China. Environ Toxicol Chem 29 1377-1384... 

Hydropower use for electricity generation is responsible for a wide array of enviromnental disturbances to river systems. Over the past decades, aquatic science research has been successful in identifying a considerable number of relationships that exist between plant operation and ecosystem quality. This increase in scientific knowledge was, however, not matched by a corresponding reduction in environmental impacts stemming from hydropower. One of the major reasons for this situation is that political, economic, and social aspects are neglected in purely scientific assessments of environmental impacts. 

---