湖沼学chapter 1 Introduction of Limnology.ppt

LIMNOLOGY Limnology is the science dealing with the physical, chemical, biological and meteorological study of inland waters. Although many limnologists are freshwater ecologists, physical, chemical, and engineering limnologists all participate in this branch of science. Limnology covers lakes, ponds, reservoirs, streams, rivers, wetlands, and estuaries, while oceanography covers the open sea. Small Headwater Stream Large Stream / Small RiverMiddle New River Gorge Limnology evolved into a distinct science only in the past two centuries, when improvements in microscopes, the invention of the silk plankton net, and improvements in the thermometer combined to show that lakes are complex ecological systems with distinct structures. Limnologists work on lake and reservoir management, water pollution control, and stream and river protection, artificial wetland construction, and fish and wildlife enhancement. An important goal of education in limnology is to increase the number of people who, although not full-time limnologists, can understand and apply its general concepts to a broad range of related disciplines. Today, limnology plays a major role in water use and distribution as well as in wildlife habitat protection. Freshwater Status Oceans cover around 70% of the earths surface and account for 97% of its water Only 3% of all water on earth is freshwater Most of this freshwater is locked away in the form of ice caps and glaciers located in the polar regions - though maybe not for much longer the way climate change is taking hold? It wont change the fact that only about 1% of all water found on this planet is easily accessible for human use. Troubled waters Problems for the global freshwater situation Freshwater is the single most essential good for our well-being. Like a giant engine working day and night, the water cycle and inherent ecosystems are the life support of the planet. Thirsty crops cause water shortages and pollution Freshwater Issues