Freshwater ecosystems are aquatic habitats with a much smaller amount of salt content than marine environments. Examples of habitats in freshwater ecosystem are rivers, ponds, lakes and marshes. This ecosystem supports wildlife and plants that cannot live in saltwater. Two of the Five Great Lakes, Lake Ontario and Lake Erie, touches the northern and western borders of New York State. New York State is also home to the Finger Lakes region, a collection of 11 natural lakes in Central New York. Some of New York's longest rivers are the Hudson River and St. Lawrence River. The 315-mile Hudson River runs from the Adirondack Mountains to the Atlantic Ocean, while the St. Lawrence River starts at Lake Ontario and empties into the Atlantic Coast in Quebec, Canada.
According to the New York State DEC, the forest ecosystem makes up 63 percent of New York's total surface area. New York Sate has approximately 19 million acres of forests. Four million forested acres is in the care of the DEC and includes state parks such as the Catskill Forest Preserve and Stewart State Forest. Most of New York's forests have deciduous trees, including birch, maple and elm. These trees lose their leaves during the fall and winter months.
As opposed to freshwater ecosystems, marine ecosystems support wildlife and plants that require the saline in marine water for life. This ecosystem includes bodies of water such as oceans, estuaries, seas and salt marshes. The southeastern corner of New York is at the edge of the Atlantic Ocean, the second-largest marine ecosystem in the world. Other marine ecosystems by New York includes Long Island Sound, Great South Bay and Gardiners Bay; all three bodies of water are located next to Long Island.
An urban ecosystem consists of human-populated environments such as cities, towns and villages. Inquire Institute, a program for environmental conservation students at Columbia University, says studies on urban ecosystems focus on three aspects: biodiversity -- the ethnicities of people within an urban area -- water and how much energy an urban ecosystem consumes. The most populated urban ecosystem in the United States, New York City, is also the largest city in the Empire State. According to "USA Today," the 2010 Census estimated over 8 million residents live in New York City.