Posted on 04 May 2011.
The word “tundra” is derived from the French “tunturi,” which means “treeless plain.” It is the best way to describe the harsh climate. No other ecosystem is colder than the tundra. Tundra comes in three different variations, arctic, antarctic and alpine. Antarctic tundra is essentially a desert covered in ice formed by the frozen ocean around Antarctica. Alpine tundra is found at the top of mountains, past where trees grow. Arctic tundra is located close to the North Pole and extends south to the taiga. All tundra has these similar characteristics:
- Extreme cold
- Simple structure of vegetation
- Short growth and reproduction seasons
- Dead organic materials provide most of the energy and nutrients in the system
- Large oscillations in the population
Climate of the Tundra
The growing season lasts for a meager 50 to 60 days in Arctic tundra, and about 180 days for Alpine tundra. The average temperature in winter is -30 degrees Fahrenheit. In the brief summer, the temperature averages 37 to 54 degrees. A layer of permafrost, or permanently frozen soil, is always present, although it’s depth is variable. Bogs and ponds form in the Arctic tundra in the summer when the permafrost melts slightly and precipitation floods the area. These bogs provide moisture for the plant life that is acclimated to the environment. Alpine tundra soil has better drainage.
Plant Life in the Tundra
The plant life that exists is simple, but of surprising diversity. The tundra is able to support:
- Reindeer moss
- Low shrubs
- Sedges and grasses
- About 400 different types of flowering plants
In addition to these plants, Alpine tundra supports:
- Tussock grasses
- Dwarf pines
The plants found in the tundra are short and grow close to the ground. They are adapted to the harsh cold.
Animal Life in the Tundra
Like plant life, the animal life is also diverse. Herbivorous mammals like voles, caribou and arctic squirrels call the Arctic tundra their home, as do the carnivorous mammals that feed on them such as arctic foxes and polar bears. Migratory birds like ravens, falcons and terns can survive here. The cold waters are filled with fish like cod, salmon and trout. Alpine tundra supports pikas, mountain goats and elk, grouse-like birds, and insects such as beetles, grasshoppers and butterflies.
Water Pollution in the Tundra
Because the arctic and alpine ecosystems are so fragile, anything the pollutes the water that the system depends on creates a grave threat to the entire system. A growing concern in the arctic tundra is the threat of oil spills, which float in the water and suffocate plant and animal life. Acid rain is an ongoing concern in the Alpine tundra ecosystem. Many mountain lakes are being rendered sterile, as they do not have much of a buffering capacity.
Posted in Water and the Environment
Posted on 27 April 2011.
The water cycle is the name given to the process that occurs in nature involving the chemical, water. The Sun heats the world’s oceans, which slowly evaporate, releasing water vapor into the atmosphere. As the water vapor rises, it cools and condenses into water droplets. These droplets form clouds, which release their water back to Earth as rainfall. Rivers carry the liquid water back into the sea, where the process begins again. The water cycle hydrates the Earth and makes human life possible.
Discovering The Cycle
People have asked the question, “What is the water cycle” ever since they have understood how water changes. Liquid water is the most powerful solvent yet discovered. Given enough time, water can dissolve almost anything. “What is the water cycle” has given rise to powerful ideas about nature. In time, the water cycle has proved to be one of the most astounding facts found in nature.
Water can be divided into two categories: freshwater and seawater. Seawater has a high salt content, which makes it bad for humans and animals to drink. Saltwater animals like fish can survive in seawater, but only freshwater is drinkable by land animals and humans. The supply of freshwater is important for the continued survival of most species of mammals.
Importance Of Freshwater To Life
Freshwater is created by the natural distillation that occurs during the water cycle. As the Sun heats the oceans, the evaporated water leaves the salt behind. The salt is too heavy to travel with the water, so the evaporated water is turned into freshwater. When this water falls as rain and snow, the lakes, rivers and streams carry the freshwater back into the ocean. The freshwater present in bodies like lakes and rivers is used by animals and humans for their needs. Humans use freshwater to drink and keep their work and living spaces clean. Animals also use it to bathe and drink.
Freshwater, Plant And Animal Life
Potable water is an important natural resource Life congregates around areas of freshwater created by the water cycle. In the Nile river delta in Egypt, greenery thrives due to the freshwater from the Nile. Surrounding the delta is a sea of sand, parched of almost every living thing. Water is essential for plant and animal life. Freshwater and plant and animal life are almost always found together. The water cycle makes life on Earth possible by making freshwater so widely available.
Posted in Questions About Water
Posted on 08 April 2011.
Where Does Water Come From? The full answer to this question should include ‘What the Earth’s original source of water is,’ ‘where the water running from our faucets comes from’ and the source of water for our water treatment plants.
Where water originally came from is still under debate, but some scientists have concluded that the water on Earth came from about a billion year’s worth of comets striking the earth, as comets typically contain ice. While much of this has accrued in ocean water, but most of us are probably more interested in the fresh water that runs from our faucets. Where does this water come from?
Local water from wells
Each locality has it’s own source for fresh water, so this is one place where water comes from. Some homes have their own private well and thus domestic water is supplied from their own well and pump. This is often untreated, but a deep well typically provides safe drinking water, as the ground provides some filtration and you can also have your water tested by a state certified lab. Check out the EPA’s recommendations for the testing of domestic drinking water from private wells.
Municipal water supply
Some homes receive their water from municipal water supply. These homes tap into the municipal water distribution system, and the home’s water use is typically measured by a water meter, later billing the home for water used. Municipal water is treated by a water treatment plant using several steps. These steps can include different kinds of filtration, clarification, and disinfection. Where does this water come from? The water treatment plant may have a source of surface water such as a lakes or rivers or ground wells, or sometimes a water treatment plant receives raw water from other municipalities.
The water cycle
The water in our lakes, rivers and ground wells is the result of the water cycle. The water cycle is well-known and includes rain, evaporation, and condensation. Some of this water also supplies underground aquifers that supply ground wells. Evaporation supplies fresh water vapor to the air that rises into the atmosphere, which cools as it rises to form clouds and rain. The rain completes the water cycle. We depend on this rain to supply the water we need from our faucets.
Posted in Questions About Water