While more developed countries have a well-established systems to develop water quality criteria (WQC), little research has been done on the adequacy of the current WQC to protect endemic species of China. In order to maintain the health of aquatic ecosystems in China, a series of projects to establish national WQC based on regional characteristics has recently been initiated. However, the esta...

Ab$tract.--Riparian vegetation is very important in determining the structure and function of stream ecosystems. Most aquatic organisms, both invertebrates and fish, are directly or indirectly dependent on inputs of terrestrial detri tus to the stream for their food. Natural changes in riparian vegetation and the biotic processing of detritus, as well as other factors, determine the kinds and a...

The U.S. Geological Survey’s Nonindigenous Aquatic Species (NAS) Database has tracked introductions of freshwater aquatic organisms in the United States for the past four decades. A website provides access to occurrence reports, distribution maps, and fact sheets for more than 1,000 species. The site also includes an on-line reporting system and an alert system for new occurrences. We provide a...

Research in probiotics for aquaculture is at an early stage of development and much work is still needed. The principal bacterial groups tested as probionts in the culture of shrimp, crab, oyster and fish have been Vibrio, Pseudomonas, Bacillus, and several lactobacilli. The available information is inconclusive, since few experiments with sufficiently robust design have been conducted to permi...

The majority of industrial organic chemicals lack identifiable structural characteristics that result in specific biological activity. These nonpolar-nonelectrolytes are acutely toxic to aquatic organisms via a nonspecific mode of action termed narcosis. The toxicity of industrial chemicals eliciting nonpolar narcosis can be reliably predicted by log P (baseline toxicity models). Using single c...

issolved gas supersaturation (DGS) is a condition that occurs when the partial pressures of atmospheric gases in solution exceed their respective partial pressures in the atmosphere. Individual atmospheric dissolved gases (oxygen, nitrogen, and trace gases such as argon and carbon dioxide) can often be supersaturated without adverse effects on aquatic and marine organisms. When the sum of the p...

A new method for the analysis of behavior in small free-swimming aquatic organisms is described. In this procedure, called countercurrent separation, a dense solution flows down along the bottom of an inclined chamber while a light solution flows in the opposite direction, upward along the top of the chamber. The attraction of animals (injected into the center of the chamber) to one solution or...