Stream Erosion

A stream is a body of water that carries pebbles and particles down a channel. Streams are one of the main contributors to how the layout of the land changes over time. They do this by carving into the mountains over time by moving sediment and water through channels. This process can take thousands to millions of years. Streams can be in different phases depending on how old or young they are. In mountain areas streams carve them and create deep canyons. Streams go through phases of erosion and deposition of sediment. Stream erosion is something that takes up most of the streams energy from friction between the bed or sides and the water. A very young stream will be very windy and create very steep valleys by having an extremely fast velocity. For an older stream the landscape will be much flatter but will still have a sloping curve. The lack of mountains will decrease the velocity greatly. The stream will look like a braided channel form instead of steep valleys. The flood plains and sediment buildup cause this stream to change shape constantly. The last phase of a stream will be in an even flatter ground and will have slowed down the velocity even greater. The stream now meanders, or curves out in various places in a U shape.  

A stream is first created when multiple runoffs from precipitation run into each other to form one big stream. This runoff is carried across the land and picks up various sediments while doing so, it also gets this sediment from the breaking down of rocks and ground in its path. Streams carry this water from their source to the ocean or sea, which make them an important part of the water cycle and replenishing water. Most of the first cities were centered on streams for a constant source of water. This sediment can be carried far down a stream or it can be deposited and stored before reaching its final place. There are three types of load in a stream: solution, suspension, and bed load. Solution load, or dissolved load, is the portion of the load that is in the solution of the flowing water. It is all organic and inorganic material that is carried in solution.  Suspended load is the portion of the stream that is permanently suspended in flowing water. Suspended load includes many different silts and clays. They remain suspended by turbulent flow. The final load is bed load, which is when pebbles and sand move along the flow of the stream without being permanently suspended in the water. These materials are too heavy and move along the bottom of the stream by rolling or sliding, which erode the channel by abrasion. Another way they move is by saltation, a jumping movement, which happens when particles suspended in the stream fall to the bed and dislodge other particles which repeat the process. These three different types of loads help to erode the surrounding rock and stream bed which adds to more sediment.

http://www.physicalgeography.net/fundamentals/10y.html

http://www.earthonlinemedia.com/ebooks/tpe_3e/fluvial_systems/geologic_work_of_streams.html

http://www.tulane.edu/~sanelson/eens1110/streams.htm

Wetlands

Wetlands serve as an important part of the water cycle. They can reduce impacts from storm damage and flooding, a vital source of recharge for groundwater, and help maintain quality in rivers. Wetlands help with water quality by filtering out pollutants as it traps sediments and absorbs excess nutrients that could pollute the water. They can also serve as an important freshwater source for people who rely on unpredictable sources.

Wetlands are important for biodiversity such as: fish, bird, and plant species. Wetlands are vital to many migratory bird species around the world. These birds keep the insect population down in the surrounding area which help farmers from getting their crops eaten.  

Wetlands are a very popular tourist spot which helps provide revenue for businesses nearby as well as aid the economy. People often visit wetlands to watch the animals, go fishing, boating, or camping nearby. People also use wetlands for a source of water to farmers in irrigation. Farmers don’t only use this water for crops, they also use them for livestock as well as domestic use.  

Wetlands also serve as a natural carbon sinks. A carbon sink is something that has a high ability to absorb carbon dioxide from the atmosphere, some examples are: forests or oceans. Wetlands that are placed along coastlines have the highest amount of carbon sequestration as well as other greenhouse gases. Australia and the Amazon are good examples of coastal wetlands.

RAMSAR is a “Convention on Wetlands and is an intergovernmental treaty that provides the framework for national action and international cooperation for the conservation and wise use of wetlands and their resources.” There are 169 parties that have signed the contract and over 2,000 Ramsar sites. There are 195 countries in the world and only 169 countries have signed, so 26 countries have not signed. It was named Ramsar after the city of Ramsar in Iran, where the Convention was signed in 1971. The headquarters are in Gland, Switzerland. The United Kingdom is the country with the highest amount of sites, but Bolivia is the county with the highest area of wetlands. The parties that have signed will meet every three years as the Conference of the Contracting Parties (COP). Many other organizations have partnered with them to give research and information to aid them in saving the wetlands. So far Ramsar has protected over 490,000,000 acres of wetlands. A wetland is defined as “are areas of marsh, fen, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres.”

Ramsar has its own association in Ohio, the Ohio Wetland Association. In the United States there are only 37 designated wetlands of international importance. Ohio contains one of those 37 sites. It is located on the Wilma H. Schiermeier Olentangy River Wetland Research Park on the campus of Ohio State’s university campus. This association conducts marsh monitoring programs, holds fundraisers, and increases awareness of the public. The association is made up of volunteers and is a

non-profit. Ohio used to have many wetlands but they have been converted to other land uses over time. The Clean Water Act has helped to alleviate the pressure on wetlands but there are still problems.

http://www.environment.nsw.gov.au/wetlands/WhyAreWetlandsImportant.htm

http://www.ohwetlands.org/ramsar-wetlands-of-international-importance.html

http://www.ramsar.org/

Urbanization Effect on Drinking Water

In the next forty years the urban areas around the world are expected to absorb all of the population growth that will also occur during that time. This will cause a serious strain on many of the utilities in the city, especially water. However this growth in population in urban areas in not only from reproduction but it is also from migration of people from other countries into new countries or even migration from rural areas. Many urban areas around the world are already in a water crises, and this growth in population will only exacerbate this problem. Most of this expected growth in urban areas is expected to occur in areas of the city that are less developed, which will only further issues with water use. These cities are not ready for the rapid growth that awaits them in just a few decades. If they do not become prepared it will create slums, blackouts, inadequate water supply and poor sanitation. The two most extreme problems are: water quality and sewage management.

As urbanization continues to grow it will create more storm runoff and erosion by having less vegetation to slow water as it moves across the land. This will also change the way water is moved around our system by having less water soak into the earth and less being restored in the local watersheds which then makes that city have to reach out further to find water for itself. Less vegetation creates the chance for more frequent flooding, and can change the physical characteristics of a stream. This is occurring in every almost every country, India, the United States, and most of Europe.

Megacities are a great example of areas where urbanization has had a negative effect on drinking water. A megacity is a metropolitan area with a total population in excess of ten million people. There are 35 megacities in existence around the world, with Tokyo being the largest. In the year 2050 about 70% of the world’s population will be in urban areas. Megacities create problems such as pollution of drinking water (poor water quality), catastrophic flooding, and inadequate access to water, poor living conditions, sewer systems overrun, and water stress.

To fix some of these problems the public needs to reduce unnecessary consumption and demand that products they use every day be made with less embedded water. Megacities and other areas with a large population need to become more sustainable with their resources. To do this they need to get everyone talking across a broad spectrum to find the best solution possible for each separate location. These solutions have to go past changing the water flow and must include getting the public more knowledgeable to reduce water use and make them more aware of law controls, reusing wastewater as well as storm water. If people will not use less water we must demand that they use less water by: offering citizens economic incentives for using less water, or having appropriate pricing of water.    

http://pulitzercenter.org/projects/asia/dhaka%E2%80%99s-challenge-megacity-struggles-water-sanitation-and-hygiene

http://www.wwf.org.uk/about_wwf/press_centre/?unewsid=5202

http://www.unwater.org/topics/water-and-urbanization/en/