Environment and the Water Cycle

Unit 4: Environment

• Natural environment encompasses all living and non-living things occurring naturally, mostly applied to Earth.

Water Cycle Stages

• Evaporation is powered mainly by the sun's energy, turning water molecules into vapor clouds.
• Condensation involves water vapor cooling at high altitudes, forming tiny droplets or ice that become clouds.
• Precipitation occurs when water droplets merge and fall as rain, snow, or hail.
• Infiltration, or percolation, is when rainwater is absorbed into the ground, with the absorption level varying by material.
• Runoff describes water flowing down mountains and hills to form rivers if it doesn't form aquifers.

Water Cycle Processes

• Evaporation turns liquid water into gas using solar energy from bodies like puddles, ponds, lakes, and oceans.
• Condensation converts water from gas to liquid, forming clouds after evaporation.
• Transport involves water within clouds being blown by strong winds.
• Precipitation is when rain, snow, hail, and sleet falls from the sky.
• Surface runoff occurs when excess water runs along the ground if the ground is already saturated.
• Infiltration is when precipitation water is absorbed into the ground, stored as aquifers.
• Transpiration is plants maintaining a stream of water to their leaves, evaporating some as vapor.

Implications of the Water Cycle

• The water cycle greatly impacts climate and the temperature on earth.
• The water cycle is integral to biogeochemical cycles, affecting all life processes.
• The water cycle cleans the air by attaching water vapor to dust during precipitation.

Disruption of the Water Cycle: Deforestation

• Trees store water, especially in rainforests. When cut down, stored water is lost.
• Trees extract groundwater, so deforestation prevents water release into the atmosphere, disrupting the water cycle's balance.
• Deforestation leads to drier climates and soil due to lacking transpiration and can turn rainforests into deserts.
• Cutting down these trees causes climate to become drier, affecting groundwater tables.
• Trees prevent water runoff, and without them, water runs off, reducing groundwater absorption and leading to lower water resources.

Carbon Cycle Steps

• Photosynthesis is when plants absorb carbon dioxide to produce sugars, starches, and other compounds, which effectively reduces carbon dioxide.
• Feeding moves carbon in biological forms along the food chain.
• Respiration is when living organisms release carbon dioxide back into the atmosphere (excretion).
• Fossilization is when dead organisms can form fossil fuels when compressed over long periods under favorable conditions.
• Combustion releases stored carbon dioxide into the atmosphere by burning fossil fuels.
• Excretion is when waste is removed from the body as urine and is broken down during decomposition.
• Egestion is the removal of feces containing carbon, broken down during decomposition.
• Decomposition is when complex compounds are broken down into simpler ones by bacteria or fungi.

Disruption of the Carbon Cycle

• Burning fossil fuels and deforestation have an effect on the carbon cycle and atmospheric carbon dioxide levels.
• Human activities affect the carbon cycle through carbon dioxide emissions (sources) and removal (sinks).
• The carbon cycle is affected when carbon dioxide is either released or removed from the atmosphere.
• Burning wood releases locked-up carbon as carbon dioxide, increasing its atmospheric concentration.
• Deforestation results in trees no longer absorbing carbon dioxide for photosynthesis, increasing atmospheric carbon dioxide.

Air Pollution - Global Warming and Greenhouse Gases

• Greenhouse effect: trapping heat energy by greenhouse gases.
• Thermal energy escapes Earth's surface, but certain gases trap that energy, causing some thermal energy to pass back.

Greenhouse Effect

• Carbon dioxide, water vapor, and methane are key greenhouse gases.
• Complete combustion of carbon-containing substances, respiration, reactions between acids and carbonates, and thermal decomposition of carbonates are sources of carbon dioxide.
• Sources of methane production are fossil fuels, livestock farming, and decomposing vegetation.

Increasing Carbon Dioxide Levels

• Burning fossil fuels increases carbon dioxide.
• More fuel is used as the human population increases.

Global Warming

• Increases in carbon dioxide enhance the greenhouse effect and cause global warming.

Impact of Climate Change

• Climate change includes ice melting faster in the Arctic and Antarctic, oceans warming and expanding, and shifts in species habitats.

Global Warming: Causes and Solutions

• Causes includes an increase in CO2 in the air due to agriculture, deforestation, and burning fossil fuels as well as effects such as melting ice, rising sea levels, and climate change.
• Solutions includes reducing CO2 emissions through the development of clean energy and reforestation.

Air Pollution: Acid Rain

• Acid rain happens when sulfur dioxide (SO2) and nitrogen oxides (NOX) are released into the atmosphere.
• Sulfur dioxide is produced when hydrocarbon fuels containing sulfur impurities are burned.

Effects of Acid Rain

• It damages buildings and statues by reacting with metals and rocks.
• It damages the waxy layer of leaves, hindering mineral absorption.
• It makes rivers and lakes too acidic, endangering aquatic life.

Oxides of Nitrogen

• Nitrogen and oxygen react at high temperatures to produce oxides of nitrogen.
• Nitrogen oxides are atmospheric pollutants that can react in sunlight to form smog and cause respiratory issues.

Ozone Depletion

• Ozone depletion refers to the thinning of Earth's ozone layer, caused by human-produced chemicals.
• It is most extreme in polar regions and increases harmful UV radiation.

Causes of Ozone Depletion

• Chlorofluorocarbons(CFCs) from solvents, aerosols, refrigerators etc as the main cause, where molecules break down and release chlorine atoms that destroy ozone.
• Unregulated rocket launches result in more ozone layer depletion.
• Nitrogenous compounds such ad NO2, NO, and N2O cause ozone layer depletion.
• Natural processes such as sun-spots and stratospheric winds as well is volvanoes depletes the ozone layer.

Ozone-Depleting Substances

• Chlorofluorocarbons come from refrigerators, air conditioners, solvents, and dry-cleaning agents.
• Halons and carbon tetrachloride come from fire extinguishers.
• Methyl chloroform comes from adhesives and aerosols.
• Hydrofluorocarbons come from fire extinguishers and air conditioners.

Ozone Depletion - Harmful Effects

• Increases risk of skin cancer, sunburns, cataracts, and immune system damage.
• Can lead to skin and eye cancer in animals.
• Negatively affects plants, crops and may lead to minimal plant growth, smaller leaf size, and flowering and photosynthesis in plants, lower quality crops for humans.

Land Pollution

• It is the deposition of solid or liquid waste that contaminates soil and groundwater, threatens health, and causes nuisances.

Causes of Land Pollution

• Agricultural activities disrupt normal nutrient cycles, causing widespread use of herbicides, insecticides, bactericides, and fertilizers.
• Mining activities harm ecosystems, damage biodiversity, cause soil erosion, and pollute water supplies.
• Nuclear waste and Non-biodegradable plastic harms the soil.
• Mining destroys habitats, causes soil erosion and pollutes water.

Problems Caused by Non-biodegradable Waste

• Uncontrolled landfills cause pollution and diseases among nearby residents.
• Waste can cause pipe blockages and groundwater contamination and chemicals, biomedical waste, and plastics can pollute bodies of water.

Alternatives to Non-Biodegradable products

• Use biodegradable materials or compost organic material instead of discarding it as waste.
• Reprocess non-biodegradable materials so that they can be broken down into their original components and then eliminated from the environment.

Steps to Dispose of Non-Biodegradable Waste

• Scientific methods such as incineration must be used.
• Usage of biodegradable plastic should receive prime focus.
• The civic authorities must use different colored baskets & vehicles to segregate wastes.

Water Pollution

• It is the contamination of water bodies, usually a result of human activities, so that it negatively affects its uses.
• Water pollutants include bacteria, viruses, parasites, fertilizers, pesticides, pharmaceutical products, nitrates, phosphates, plastics, fecal waste, and radioactive substances.

One Main Cause of Water Pollution: Eutrophication

• Eutrophication is caused by accumulated herbicides and pesticides into the lakes and the rivers.
• Steps of Eutrophication is excessive nutrients from fertilizers are flushed from the land into rivers or lakes by rainwater that causes algae to bloom and oxygen is depleted.

Ways to Prevent Water Pollution

• Pick up litter and throw it away in a garbage can.
• Blow or sweep fertilizer back onto the grass if it gets onto paved areas.
• Never clean up a spill by hosing it into a storm drain.

Deforestation

• It is defined as removal of trees from what was previously a forest, for conversion to non-forest use.
• Deforestation causes are agricultural expansion, wood extraction, and infrastructure expansion.
• Effects on ecosystem are from soil erosion and eutrophication to habitat destruction.

Factors Affecting Human Impact on the Environment

• Social, economic and increasing population are examples that affect human impact in the environment.
• Social means traveling abroad.
• Economic mean farmers may grow and sell more crops to make more profit.
• Increasing population means more houses are built.

What causes the ecosystem?

• Natural disasters or made made causes can affect the ecosystem.
• Natural disasters such as fire, drought, floods or even eruptions.
• Made made such as air pollution, water pollution, land pollution etc.

Ecosystem Terms

• Environment: All the conditions that surround a living organism
• Habitat: The place where an organism lives
• Population: All the members of a single species that live in a habitat
• Community: All the populations of different organisms that live together in a habitat( all populations of different species)
• Niche: The role (job) of the organism in the ecosystem

Biodiversity

• It is important for sustaining life on Earth because it prevents any one species from throwing out the balance of nature.
• Rainforest has more biodiversity than the desert.
• Healthy environment has a diverse set of animals and plants all depending on one another.

Food Chains

• Any food chain starts with a producer.
• Means an organism that produces their own food like plants and algae as they can make their own food by photosynthesis.
• Consumers mean that they get their energy by consuming (eating) other organisms.

Types of Consumers

• Consumer that only eats plants is called an HERBIVORE
• Consumer that only eats other animals is called a CARNIVORE.
• Consumer that eats both plants and animals is called an OMNIVORE

What are Decomposers

• Organisms that breakdown the dead bodies and turn them into nutrients.
• The nutrients is good for growing plants.
• Water
• The Sun is the ultimate source of energy for all living things.

Trophic Level

• Trophic food is the position of an organism in food chain or food web is called trophic level.
• Consumers feed at more than one trophic level.