ESS quiz chapter 5.

What are the three types of particles depending on size?
Clay, sand and silt.

Name three out of the five components of soil.
Rock particles, humus, air, water and living organisms.

What type of soil has very bad drainage?
Clay.

What does NPK stand for in a fertilizer?
Nitrates, phosphates and potassium.

Under what conditions is the salinization process favored?
When precipitation is lower than evaporation.

What is the name of the phenomenon of the nutrients being dragged down to the lower layers of the soil?
Leeching.

The ability of a soil system to allow the passage of liquids and gasses is called...
permeability.

What kind of farming appears as opposed to "commercial" farming?
Subsistence farming.

Name three of the four factors that determine the choice of food in humans.
Climate, cultural and religious, political and socio-economic.

The unit of energy is the...
Joule

Mention one technique that can reduce the erosion by wind.
Cover crops, shelter belts, strip cultivation.

The ratio between the energy output and the energy input of an agricultural system is the...
efficiency

What type of soil degradation can take place as a result of animal farming?
Overgrazing.

The loss of soil due to the action of rain and wind is called...
erosion.

In addition to depleting the soil of nutrients, what other harmful effect does overcropping have?
Making the soil susceptible to erosion by wind.

Mention one technique that can reduce the amount of water crops need.
Trickle flow irrigation.

Mention one technique that can reduce the harmful effect of plowing.
Terrace, contour plowing.


Special questions:
True or false (and explain).
Soils rich in clay are more resilient against nutrient depletion than sandy soils.
True, because the particle is smaller and that makes it easier for metals and inorganic salts to dissolve.


Explain why a cattle farm will most likely have an efficiency lower than a corn field.
Cattle are consumers and corn is producer, therefore cattle will require feeding while corn gets its energy from sunlight.
Following the rule that states "the efficiency is higher the lower we go in the trophic chain" is also acceptable.