NitrateNitrate is a polyatomic ion with the chemical formula NO3−. Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate. The ion is the conjugate base of nitric acid, consisting of one central nitrogen atom surrounded by three identically bonded oxygen atoms in a trigonal planar arrangement. The nitrate ion carries a formal charge of −1.
Freshwater ecosystemFreshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes, ponds, rivers, streams, springs, bogs, and wetlands. They can be contrasted with marine ecosystems, which have a larger salt content. Freshwater habitats can be classified by different factors, including temperature, light penetration, nutrients, and vegetation. There are three basic types of freshwater ecosystems: Lentic (slow moving water, including pools, ponds, and lakes), lotic (faster moving water, for example streams and rivers) and wetlands (areas where the soil is saturated or inundated for at least part of the time).
Calcium nitrateCalcium nitrate, also called Norgessalpeter or Norwegian salpeter, is an inorganic compound with the formula Ca(NO3)2(H2O)x. The anhydrous compound, which is rarely encountered, absorbs moisture from the air to give the tetrahydrate. Both anhydrous and hydrated forms are colourless salts. Calcium nitrate is mainly used as a component in fertilizers, but it has other applications. Nitrocalcite is the name for a mineral which is a hydrated calcium nitrate that forms as an efflorescence where manure contacts concrete or limestone in a dry environment as in stables or caverns.
Southern United StatesThe Southern United States (sometimes Dixie, also referred to as the Southern States, the American South, the Southland, Dixieland, or simply the South) is a geographic and cultural region of the United States of America. It is between the Atlantic Ocean and the Western United States, with the Midwestern and Northeastern United States to its north and the Gulf of Mexico and Mexico to its south. Historically, the South was defined as all states south of the 18th century Mason–Dixon line, the Ohio River, and 36°30′ parallel.
Participation biasParticipation bias or non-response bias is a phenomenon in which the results of elections, studies, polls, etc. become non-representative because the participants disproportionately possess certain traits which affect the outcome. These traits mean the sample is systematically different from the target population, potentially resulting in biased estimates. For instance, a study found that those who refused to answer a survey on AIDS tended to be "older, attend church more often, are less likely to believe in the confidentiality of surveys, and have lower sexual self disclosure.
Culture of the Southern United StatesThe culture of the Southern United States, Southern culture, or Southern heritage, is a subculture of the United States. From its many cultural influences, the South developed its own unique customs, dialects, arts, literature, cuisine, dance, and music. The combination of its unique history and the fact that many Southerners maintain—and even nurture—an identity separate from the rest of the country has led to it being the most studied and written-about region of the U.S.
