Porcine reproductive and respiratory syndrome (PRRS) is a widespread viral disease that affects domestic pigs. Symptoms include reproductive failure, pneumonia and increased susceptibility to secondary bacterial infection. Multiple strains of the virus with considerable variation in virulence explain the broad spectrum of clinical manifestations of the disease. (https://www.woah.org/en/disease/porcine-reproductive-and-respiratory-syndrome/)
Portion of rainfall, melted snow or irrigation water that flows across the grounds surface and is eventually returned to streams. Run-off can pick up pollutants from air or land and carry them to receiving waters. (United Nations (1997): Glossary of Environment Statis tics. Studies in Methods, Series F, No. 67.)
Note
Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity toward a stream channel (always above the main groundwater level) and eventually empties into the channel. Runoff also includes groundwater that is discharged into a stream; streamflow that is composed entirely of groundwater is termed base flow, or fair-weather runoff, and it occurs where a stream channel intersects the water table. The total runoff is equal to the total precipitation less the losses caused by evapotranspiration (loss to the atmosphere from soil surfaces and plant leaves), storage (as in temporary ponds), and other such abstractions. In some countries, runoff implies surface runoff only.
Subsurface runoff is the water that infiltrates in the vadose zone (unsaturated zone), from rain, snowmelt, or other sources, and moves laterally towards the streams. Vadose zone extends from the top of the ground surface to the water table. (http://disc.gsfc.nasa.gov/hydrology/data-holdings/parameters/subsurface_runoff.shtml)
Meiobenthos are the smaller benthos. They are smaller than the more visually obvious macrobenthos (e.g., segmented worms, echinoderms, clams, snails, etc.). Conversely, they are larger than the microbenthos – a term restricted primarily to Protista, unicellular algae, and bacteria. Meiobenthos (benthos=bottom living) refers specifically to those meiofauna that live on or in sediments. (B.C. Coull, G.T. Chandler, Meiobenthos, Editor(s): John H. Steele, Encyclopedia of Ocean Sciences, Academic Press, 2001, Pages 1705-1711, ISBN 9780122274305,
https://doi.org/10.1006/rwos.2001.0212. (https://www.sciencedirect.com/science/article/pii/B012227430X002129))