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## How does the ocean absorb carbon dioxide?

James J.
Featured 3 months ago

1) Differences in pressure between the air and the ocean cause carbon dioxide to be exchanged and 2) algae and phytoplankton absorb carbon dioxide.

#### Explanation:

The ocean can absorb carbon dioxide (${\text{CO}}_{2}$) in 2 ways: diffusion from the atmosphere and through photosynthesis in plankton and algae.

Carbon dioxide moves between the atmosphere and the ocean by molecular diffusion: a difference between ${\text{CO}}_{2}$ pressure in the atmosphere and ocean causes ${\text{CO}}_{2}$ to be exchanged (source). The ${\text{CO}}_{2}$ moves from the air to the water, when the atmospheric pressure of ${\text{CO}}_{2}$ is higher. The ${\text{CO}}_{2}$ is dissolved in the ocean because it is soluble.

The solubility of carbon dioxide varies based on salinity and temperature of the water and there is a finite amount that the water can absorb. The colder the water, the more ${\text{CO}}_{2}$ can be dissolved.

The solubility of ${\text{CO}}_{2}$ in water is demonstrated in the video below.

Another way in which the ocean absorbs ${\text{CO}}_{2}$ is through some of its lifeforms. Phytoplankton and algae both photosynthesize in the ocean. They both consume ${\text{CO}}_{2}$ using sunlight and release ${\text{O}}_{2}$.

## What are some differences between traditional and modern agriculture?

Kate M.
Featured 2 months ago

Modern agriculture uses advanced technology, it is less labor intensive than traditional agriculture, and the yield quantity is larger.

#### Explanation:

Modern agriculture uses advanced technology, it is less labor intensive than traditional agriculture, and the yield quantity is larger because there is a focus on maximizing production and maintaining a consistent quality.

Modern agriculture uses advanced technology , such as plant breeding techniques and pesticides. Seeds that are hybrids may be used and other gene editing techniques applied.

Modern agriculture is less labor intensive than traditional agriculture because there is a greater reliance on machinery . This is in terms of both harvesting and growing the plants but also in cases where one is applying fertilizers and pesticides.

Some equipment used in modern agriculture:

We also see monocultures and large scale animal agriculture where livestock is confined to very small spaces.

Production is greater in modern agriculture than traditional agriculture. There is usually an emphasis on producing consistent products with modern agriculture also. For example, a tomato that grew in an atypical shape may be tossed out rather than brought to market. Note that product quality is often higher in traditional agriculture.

Misshapen fruits not included in modern agriculture:

## How does ground water move underground?

G_Ozdilek
Featured 2 months ago

Groundwater moves in pore space. The flow in a porous medium (subsurface) occurs between particles (sand, silt, gravel, etc. or a mix of these).

#### Explanation:

Groundwater moves in pore space. The flow in a porous medium (subsurface) occurs between particles (sand, silt, gravel, etc. or a mix of these).

If porosity (porous volume in a given subsurface volume) is high, groundwater moves fast as a rule of thumb. A simple velocity definition is provided for groundwater flow analysis. It is discharge velocity or specific discharge. It is defined as water discharge through a representative area of porous medium/representative total area.

Similar to surface flow, water flows from higher elevations to lower elevations in the subsurface as groundwater flow.

## What do these terms mean in the nitrogen cycle: denitrification, nitrogen fixation, lightning, bacteria, and nitrates?

G_Ozdilek
Featured 2 months ago

Here they are:

#### Explanation:

Denitrification: A biochemical process in which nitrates are reduced to ammonia or nitrogen gas (in the atmosphere the most abundant gas) by bacterial activity

Nitrogen fixation: The process of converting inorganic, molecular nitrogen in the atmosphere to ammonia or nitrate.

Lightning: Lightning oxidizes nitrogen, producing nitric oxide. In nature, essentially all other conversions of molecular nitrogen to biologically useful forms are conducted by bacteria.

Bacteria: Unicellular or filamentous microorganisms lacking chlorophyll, vital to pollution control because they occur in decaying (decomposing) matter in air, on the land, and in the oceans, and assist in the decaying process. An image of them attached below.

Nitrates: $N {O}_{3}$ Nitrate is an inorganic compound composed of one atom of nitrogen (N) and three atoms of oxygen (O); the chemical symbol for nitrate is $N {O}_{3}$. Nitrate is not normally dangerous for the health unless it is reduced to nitrite ($N {O}_{2}$).

## Explain four different ways to protect against soil degradation?

Lia
Featured 1 week ago

Crop rotation, contour farming, terracing, and shelter belt.

#### Explanation:

Crop rotation is a huge benefit when fighting against soil degradation. Annually or so, the crop on one patch of land is rotated, so one year is wheat, the next soybeans, etc. The diversity of plants help to maintain soil quality.

Contour farming is also a great way to battle soil degradation. This is pretty much plowing ridges in the soil to prevent run-off of water and nutrients, etc to minimize soil erosion.

Terracing is most commonly seen in rice fields. And since rice needs lots of water, terracing, or forming of stair-like steps will minimize the water loss in fields, and will maintain soil and prevent erosion.

Finally, the shelter belt is also a great way to maintain soil health. In fields, trees are planted in a line or a belt, to block the wind to prevent top soil being blown away.

## What are the roles of bacteria in the nitrogen cycle?

Lia
Featured 1 week ago

Bacteria helps the nitrogen cycle along throughout many of the processes.

#### Explanation:

In the nitrogen fixation process, nitrogen fixing bacteria converts the ${N}_{2}$ in the atmosphere into $N {H}_{3}$ (ammonia). This bacteria binds hydrogen molecules with the gaseous nitrogen to form ammonia in the soil.

During assimilation, or when plants take up nitrates from the soil, bacteria aid in the process with the plants in making ammonia. Animal wastes is also a major place where bacteria thrives and produces ammonia. The process in which assimilation occurs in plants, and then bacteria converts the nitrates to ammonia is called ammonification.

From the conversion of ammonia to nitrites, bacteria also aids in this process called nitrification. The nitrifying bacteria mostly present in soils, oxidize ammonia into nitrites, and from nitrites to nitrates.

Finally, the process of denitrification also has bacteria present to aid in converting nitrates back into a gaseous form of nitrogen in the atmosphere.

In a nutshell, bacteria aids in the nitrogen process through nitrogen fixation, assimilation, nitrification, and finally denitrification.

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