OUTPUT 1
1. What is environmental science and why is it important?
Answer:
Environmental science is the study of the interactions between the systems of the
Earth and the human systems. Specifically, environmental science studies the interactions
between the following systems: The Earth itself, which includes the land, water,
atmosphere, and other natural resources. Living systems, which include plants, animals,
and other organisms. Human systems include populations, societies, and economies. It is
important because the human population is putting increasing pressure on the planet, and
understanding how these interactions work is crucial for finding ways to live sustainably.
Environmental science can help us to understand the impacts of human activities on the
environment and to develop solutions for environmental problems. Solving these problems
will require a multidisciplinary approach that draws on knowledge from various fields,
including biology, chemistry, physics, geology, economics, sociology, and political
science. Environmental science plays a vital role in helping us to build a sustainable future
for ourselves and future generations.
2. Differentiate open and closed environmental system and cite examples for each.
Answer:
An open environmental system allows matter and energy to flow into and out of a
system, while a closed system conserves matter but allows energy to flow. Matter on Earth
is a closed system, meaning the amount of matter is conserved and cannot be created or
destroyed. This has implications for the availability of resources like minerals, which are
finite. Energy, on the other hand, is considered an open system on Earth. It continuously
enters the Earth system from the Sun and is eventually lost as heat. Both types of systems
play critical roles in ecological balance and sustainability. Examples of open and closed
systems include the Earth's atmosphere, oceans, biosphere, crust, mantle, and core.
The Earth's atmosphere is an open system, as matter and energy can flow into and
out through various sources, such as volcanic eruptions, fossil fuel burning, and radiation.
Oceans are open systems, as matter can enter through rivers and runoff, while energy can
flow from the sun and out through evaporation. The Earth's biosphere is an open system,
as matter and energy can flow into and out through photosynthesis, food consumption,
respiration, and decomposition.
The Earth's crust is a closed system, as matter is conserved, but energy can flow
into and out through various sources. The Earth's mantle is a closed system, as matter is
conserved, but energy can flow into and out through tectonic plate movement. The Earth's
core is a closed system, as matter is conserved, but energy can flow into and out through
radioactive decay and tectonic plate movement.
3. Discuss the rock cycle.
Answer:
The rock cycle is a continuous process in which rocks are constantly being
transformed from one type to another. It involves three main types of rocks: igneous,
sedimentary, and metamorphic. Igneous rocks form from cooled magma or lava. As
magma or lava cools, the minerals in the rock begin to crystallize. These rocks can break
down into sediments, which form sedimentary rocks. Sedimentary rocks are formed when
sediments are deposited and then compacted and cemented together. Under heat and
pressure, sedimentary rocks turn into metamorphic rocks. Metamorphic rocks can melt
back into magma, which cools into new igneous rocks, continuing the cycle of rock
transformation.
4. Discuss the different soil horizons/levels
Answer:
As soil forms, it develops different layers or horizons. At the top is the O horizon,
also known as the organic horizon. It is made up of dead and decaying plant and animal
material. Below the O horizon is the A horizon, which is the topsoil layer and is made up
of a mix of minerals and organic matter. It is the most fertile layer of soil and is where most
plants grow. In certain soil horizons, there is the E horizon, often called the eluviation layer,
which is defined by its lighter color and significant leaching activity. This layer typically
consists of sand and silt particles as water movements wash away soluble nutrients and
minerals. As we go deeper, we have the B horizon, also known as the subsoil, which
accumulates materials that leach down from the upper horizons. The C horizon, also known
as the parent material, lies below the B horizon and is made up primarily of weathered rock
and mineral material.
5. Discuss how stratospheric ozone gets destroyed.
Answer:
Stratospheric ozone gets destroyed when it is exposed to chlorofluorocarbons
(CFCs). CFCs are a group of chemicals that were widely used in refrigerants, air
conditioners, and aerosol sprays. When CFCs are released into the atmosphere, they rise
up to the stratosphere, where they are exposed to ultraviolet (UV) radiation from the sun.
Upon reaching the stratosphere, CFCs are exposed to intense ultraviolet (UV) radiation,
causing them to dissociate and release chlorine atoms. Chlorine atoms then react with
oxygen molecules, destroying them.
6. Discuss how the el nino la nina oscillation happens.
Answer:
El Niño and La Niña are opposite phases of the El Niño-Southern Oscillation
(ENSO). ENSO refers to temperature oscillations in the central and eastern Pacific Ocean,
as well as air pressure variations in the same region. During an El Niño event, the trade
winds that normally blow east-west over the Pacific Ocean weaken or reverse. This allows
warm water from the western Pacific to travel eastward toward South America's coastline.
The shift in water temperature has an impact on global weather patterns. In contrast, during
a La Niña event, the trade winds are stronger than usual, pushing more warm water towards
the western Pacific. This results in cooler-than-average water temperatures in the central
and eastern Pacific. La Niña events also have significant impacts on global weather
patterns.
7. Discuss the hydrologic cycle.
Answer:
The hydrologic cycle is a continuous circulation of water above, below, and on the
Earth’s surface. There are processes involving this cycle, such as evaporation,
condensation, precipitation, surface runoff, and groundwater flow. The water from lakes,
swamps, and other water bodies evaporates due to the heat of the sun, and it turns into
water vapor in the atmosphere. This process is what we call evaporation. Afterward,
condensation happens when the water vapor rises in the atmosphere as it cools and
condenses into tiny water droplets that form a cloud. Precipitation also exists in the
hydrologic cycle. When the water droplets in clouds become heavy, they fall back to the
Earth’s surface in the form of rain. Once it falls to the surface, this can be called surface
water. It’s either going to undergo filtration or flow to the surface of other water bodies.
Moreover, when the water flows down to the soil, this can be called groundwater, which
can later resurface as springs or be extracted through wells. This continuous cycle of
circulation is essential for maintaining the Earth's water resources and supporting various
ecosystems.
8. How soil is classified and give examples of each.
Answer:
Soil can be classified based on its horizons, particle size, and chemistry. Horizons
reveal soil formation processes and environmental conditions. Soil particles are sand, silt,
and clay, with their proportion determining texture. Soil chemistry, influenced by minerals
and organic matter, affects fertility and water-holding capacity. The proportion of these
elements determines soil texture. Soil types include sand, silt, clay, loam, and peat. Sand
is well-drained and low-fertilizing, suitable for low-nutrient crops like potatoes and carrots.
Silt is moderately well-drained and fertile, suitable for moderately nutrient crops like corn
and soybeans. Clay is poorly drained but high-fertilizing, ideal for nutrient-intensive crops
like rice and wheat. Loam, a mixture of sand, silt, and clay, is well-drained and highfertilizing, ideal for moisture-intensive crops like cranberries and blueberries.
9. Discuss how salinization happens in soil.
Answer:
Soil salinization is the process by which soil becomes excessively salty, often due
to the accumulation of soluble salts. There’s what we call natural salinization, as water
evaporates in plants and leaves behind dissolved salts. Additionally, salinization can also
happen through irrigation. This can be caused by the improper irrigation practices, as this
can cause salts to accumulate in the soil. Furthermore, the clearing of vegetation can expose
the soil to more intense sunlight and higher temperatures, which can increase evaporation
and exacerbate salinization.
10. What is soil weathering and how does it happen?
Answer:
When we say soil weathering, it is the breakdown of rocks and minerals into soil.
The video stated a type of soil weathering, including physical weathering, chemical
weathering, and biological weathering. Physical weathering takes place when there are
physical processes that affect the rock, such as temperature and even being exposed to rain
and ice. These factors can physically erode and wear down rocks over time. On the other
hand, chemical weathering is the process of breaking down rocks through chemical
reactions. Lastly, biological weathering occurs on rocks due to animals and plants.