Industrial air pollutants, such as organochlorines and heavy metals, are carried to the arctic on air currents from populated areas. Lichens are a dominant life form on the tundra, and they are particularly vulnerable to air pollution because they lack roots and get the majority of their resources from the air. Because of this, lichens have historically been used as air pollution indicators.
Hurst is a city in Tarrant County, Texas, United States. Hurst is one of the Mid-Cities between Fort Worth and Dallas. it is local a suburb of Fort Worth. The city was founded by William Letchworth Hurst. As of the 2010 census, it had a population of 37,337.
Hico (pronounced high-coe) is a small city located in Hamilton County in Central Texas. The population was 1,341 at the 2000 census. The town motto is Where Everybody Is Somebody!. The county seat is Hamilton some twenty miles to the south on United States Highway 281.