Lyons Environmental Science -Cycles of Matter Worksheet

Lyons Environmental Science -Cycles of Matter Worksheet

The hydrologic cycle is the circular pathway of water on Earth from the atmosphere, to the surface, below ground, and back. Water falls to Earth as precipitation such as rain or snow. Some droplets of water reenter the atmosphere through evaporation or transpiration, which is evaporation that occurs between plant leaves and the atmosphere. Water vapor in the atmosphere condenses and forms clouds, from which precipitation falls.

A biogeochemical cycle is the movement of a particular chemical, such as oxygen, carbon, nitrogen, or phosphorous, through the living and nonliving parts of an ecosystem. In the oxygen cycle, oxygen flows into the atmosphere as a byproduct of photosynthesis. Organisms take in this oxygen and release it as carbon dioxide through respiration. Respiration and photosynthesis also figure heavily in the carbon cycle. The cycling of carbon is important because it is the building block of life.

Carbon dioxide dissolves easily in water. Once there, it may precipitate as a solid rock known as calcium carbonate (limestone). Corals and algae encourage this reaction and build up limestone reefs in the process. Carbon dioxide is released from volcanoes. Humans have a great impact on the carbon cycle because when we burn fossil fuels we release excess carbon dioxide into the atmosphere. Some believe this causes global warming, because the carbon dioxide in the atmosphere acts like a blanket trapping heat in the atmosphere. Other human activities that can affect the carbon cycle are agriculture, deforestation, and reforestation.

Nitrogen is used by living organisms to produce a number of complex organic molecules like amino acids, proteins, and nucleic acids Proteins make up skin and muscle, among other important structural portions of your body, and all enzymes are proteins. Since enzymes carry out almost all of the chemical reactions in your body, it's easy to see how important nitrogen is.

78% of the atmosphere is nitrogen; however it cannot be taken up by many living organisms. Bacteria and lightening convert nitrogen in the air into usable forms. Plants can only take up nitrogen in two solid forms: ammonium ion (NH4+ ) and the ion nitrate (NO3- ) These forms of nitrogen are used by plants to make amino acids (proteins) and nucleic acids (DNA and RNA). The activities of humans have severely altered the nitrogen cycle. Some of the major processes involved in this alteration include: The application of nitrogen fertilizers to crops has caused increased rates of nitrates into groundwater. The additional nitrogen entering the groundwater system eventually flows into streams, rivers, lakes, and estuaries. In these systems, the added nitrogen can lead to eutrophication. Increased amounts of nitrogen from fossil fuel combustion contribute to acid rain. Livestock ranching and sewage leaching also release a large amount of ammonia into the environment. This nitrogen enters the soil system and then the hydrologic system through leaching and runoff.

The phosphorous cycle begins when phosphate is released by the erosion of rocks. Plants and fungi can take up the phosphates with their roots. Phosphorous moves from the producers to the consumers via the food chain. Phosphorous is returned to the soil through the decomposition of plants and animals. Phosphorous may leach into groundwater from the soil, settling into sediment. Over time this sediment forms into rocks. When these rocks erode the, cycle begins again. Human influences on the phosphate cycle come mainly from the use of fertilizers, manure from feedlots, and sewage treatment plants.

Nutrient Cycles Worksheet

Instructions: On a separate sheet of paper, put your NAME, PERIOD, and the title “Nutrient Cycles Worksheets.” For each of the following cycles, put the cycle name. Then write the following sentences or questions. Fill in the blanks using the words provided in the word bank. Make sure to underline the filled-in words.

Carbon Cycle

1. Plants use CO2 in the process of __________ to make ___________ & oxygen.

2. Animals and plants use oxygen in the process of ____________ to make ATP, which makes more CO2.

3. In the past, deposits of carbon were stored when dead plants and animals ______________.

4. Today these deposits are burned as fossil fuels. The 3 types of fossil fuels are ___________________, _________________, and ___________________.

5. More CO2 is released in the atmosphere today than in the past because of _____________________.

6. Too much CO2 in the atmosphere may be responsible for the _______________________ effect, in which gas molecules in the atmosphere trap heat around the Earth.

7. The chemical equation for photosynthesis is:

Oxygen Cycle

1. Plants release 430-470 billion tons of oxygen during the process of ______________________.

2. Atmospheric oxygen in the form of ____________________ (O3) provides protection from harmful ultraviolet (UV) rays.

3. Oxygen is found everywhere on Earth, from earth’s _________________ (ground & rocks), to the _____________, where it is dissolved.

4. Oxygen is vital for ________________ by plants and animals, a process which produces CO2 and water.

5. Oxygen is also necessary for the decomposition of _________________ by bacteria and fungi, which turns it into other elements necessary for life.

6. The chemical equation for cellular respiration:

Nitrogen Cycle

Extra Information that You DO NOT have to copy:

78% of the atmosphere is nitrogen; however it cannot be taken up by many living organisms. Bacteria and lightening convert nitrogen in the air into usable forms. Plants can only take up nitrogen in two solid forms: ammonium (NH4+ ) and nitrate (NO3- ). These forms of nitrogen are used by plants to make amino acids (proteins) and nucleic acids (DNA and RNA). The activities of humans have severely altered the nitrogen cycle. Some of the major processes involved in this alteration include: The application of nitrogen fertilizers to crops has caused increased rates of nitrates into groundwater. The additional nitrogen entering the groundwater system eventually flows into streams, rivers, lakes, and estuaries. In these systems, the added nitrogen can lead to eutrophication. Increased amounts of nitrogen from fossil fuel combustion contribute to acid rain. Livestock ranching and sewage leaching also release a large amount of ammonia into the environment. This nitrogen enters the soil system and then the hydrologic system through leaching and runoff.

1. Our atmosphere is made up of________ nitrogen gas.

2. Animals and plants cannot directly use nitrogen gas found in our_______________.

3. Special bacteria “fix” nitrogen in the air so other organisms can use it. These bacteria are called _________________ bacteria.

4. Organisms use nitrogen to make _______________ and nucleic acids (DNA and RNA).

5. Bacteria break down animal waste and create _________ and _____________, which are nitrogen-rich products easily used by plants.

6. ____________ bacteria in the soil break down ammonia into the gaseous form of nitrogen, which is not available for use by plants or animals.

7. In another part of the cycle, animals eat _____________ that contain nitrogen, which is again returned to the soil by animal ____________ or decaying _______________ and ______________.

Water Cycle

Extra Information that You DO NOT have to copy:

The water (hydrologic) cycle is the circular pathway of water on Earth from the atmosphere, to the surface, below ground, and back. Water falls to Earth as precipitation such as rain or snow. Some droplets of water reenter the atmosphere through evaporation or transpiration, which is evaporation that occurs between plant leaves and the atmosphere. Water vapor in the atmosphere condenses and forms clouds, from which precipitation falls.

1. Most water on Earth is stored in the ______________.

2. Surface water on Earth includes freshwater found in _______________________.

3. Surface water in oceans and lakes and rivers is turned into vapor (gas) through the process of ________________________________.

4. Water becomes liquid form again in clouds in the ____________________, through the process of _______________________.

5. Liquid water falls back to Earth as different forms of _________________, such as ___________, snow, and sleet.

6. Animals release water during respiration and as ________________, such as in urination.

7. Plants loose water through their leaves, which is called ____________________________.

8. Water that is stored underground, such as in aquifers is called _____________________________.

Phosphorous Cycle

Extra Information that You DO NOT have to copy:

The phosphorous cycle begins when phosphate is released by the erosion of rocks. Plants and fungi can take up the phosphates with their roots. Phosphorous moves from the producers to the consumers via the food chain. Phosphorous is returned to the soil through the decomposition of plants and animals. Phosphorous may leach into groundwater from the soil, settling into sediment. Over time this sediment forms into rocks. When these rocks erode the, cycle begins again. Human influences on the phosphate cycle come mainly from the use of fertilizers, manure from feedlots, and sewage treatment plants. This can put too much phosphorus in bodies of water, which can result in over-growth of plants and algae, a process called eutrophication. This overgrowth of plants and algae can result in lowered oxygen levels in the water, possibly killing other aquatic organisms such as fish and insects.

1. Phosphorous is mostly found in ______________.

2. It is an essential nutrient for life, as it makes up important molecules like ______________.

3. In the Phosphorous Cycle, phosphorous moves between the soil and __________, which are eaten by animals. The animals use phosphorous, and then their ____________ products help return the sulfur for the next generation of phosphorous in the soil.

4. Some of the phosphorous in soils can be washed away into water __________.

5. Another source of phosphorous comes from man-caused __________________.

6. Too much phosphorous in water leads to plant __________________, strangling all other life in the water.

EXTRA CREDIT – 10 Points Added if you do the Sulfur Cycle!

Sulfur Cycle

1. Sulfur in its pure elemental state is most often found near active ________________________.

2. Sulfur is found in all of Earth’s environments, including the air, the hydrosphere ( ________-portion), the biosphere (living portion), and the lithosphere (___________-portion).

3. Many sulfates, a solid form of sulfur, come from chemical weathering (breaking-down) of _______________ that contain sulfur.

4. Another major source of sulfur is from ____________________ caused by man-made activities. These are mixed with water in the air, falling as ___________ into water basins.

5. The gas, _______, smells like rotten eggs.

6. One of the most important sulfur compounds is the acid ____________________________, which is used to make fertilizers, automobile batteries, iron and steel, and plastics.

7. Other uses for sulfur include ______________________ (kills insects) and _____________ (used to start fires).