ENVR101 Exam 4 Study Flashcards
(147 cards)
1
Q
What is soil?
A
Interface between the Lithosphere and Hydrosphere. It is geological and biological. It is a mixture of minerals, organic material, living organisms, air, and water that TOGETHER support the growth of plant life.
2
Q
How long can it take to make organic top soil?
A
200-2000 years
3
Q
What are the 2 key processes of making organic top soil?
A
- Decomposition of plant material from above
2. Weathering of rock from below
4
Q
Describe the physical or mechanical process of weathering.
A
As rock becomes exposed at the Earth’s surface, they are physically and chemically changed through weathering process (exposed initially through glacier retreats or mountains)
5
Q
What is a key part element weathering?
A
Water
6
Q
Describe the chemical process of weathering.
A
Involves the alteration of the rock in such a manner that it is more likely to fragment or be dissolved; i.e. acidic rain.
7
Q
What is a key factor of weathering and the formation of soil?
A
Erosion
8
Q
What is erosion
A
The movement of particles from high to low elevation. With physical and chemical weathering, the rock erodes.
9
Q
What is the “parent” material of soil?
A
The core material that comes from the breakdown of rocks on the site and the deposition of eroded materials from elsewhere.
10
Q
What is “residual” material in soil?
A
Comes from the breakdown of rocks on the site.
11
Q
What is “transported” material in soil?
A
Eroded materials from elsewhere
12
Q
What is Loess?
A
Deposition of rock material that originated from wind.
13
Q
What are the major components of soil?
A
Inorganic compounds, organisms/organic matter, air, and water.
14
Q
What are inorganic compounds in soil?
A
Solid and dissolved mineral materials (rock, sand, silt, clay, phosphorous)
15
Q
What are organic materials in soil?
A
The conversion of leaves/wood to organic debris.
16
Q
What happens if there is too much water in the soil?
A
The space is filled with tpo much water, plants cannot obtain the amount of oxygen they need, and they drown.
17
Q
Describe the difference between macronutrients and micronutrients.
A
All plants need a number of nutrients for adequate growth, some in large amounts (macronutrients), some in small amounts (micronutrients).
18
Q
What are the most common limiting nutrients in soil?
A
Nitrogen
Phosphorous
Potassium
19
Q
What is soil moisture availability and storage?
A
The amount of water available to plants and the permeability of the soil.
20
Q
What has a higher permeability: clay or sand?
A
Sand - water passes through quickly.
21
Q
What is the normal content and structure of soil?
A
25% Air
25% Water
45% Mineral
5% Organics
22
Q
What is the ideal content of organic material in soil?
A
5% organisms
10% roots
85% humus
23
Q
What is the ideal fertility for soil?
A
20% clay
40 % silt
40% sand
24
Q
When looking at a soil profile, what are you looking at?
A
The vertical horizon of soil; differentiating soil on different horizons.
25
Which Soil Horizon has the greatest content of organic matter?
Horizon "A"
26
What Soil Horizon has the heaviest concentration of minerals?
Horizon B
27
What Soil Horizon is the Bedrock?
Horizon R
28
Why is it important to know the Soil Profile?
It helps us differentiate the structure of soil in different ecological biomes.
29
What biome holds the best soil for the most productive agriculture?
Grassland Soil
30
Describe the process of leaching.
Solid particles suspended or dissolved in liquid are transported to another location.
31
What is Global Soil Fertility?
The capacity of soil to provide plants with enough nutrients and moisture to produce crops.
32
What percentage of land is suitable for agriculture in the world?
11%
33
Approximately how many people rely on food grown on 11% of Earth's surface?
6-7 billion
34
What happens if the soil is too compact?
There are not enough air pockets necessary to retain the water and allow for absorption of oxygen or growth of the root system.
35
What is "Loam"?
An ideal mix of 50% sand, 40% silt and 40% clay. It retains water and allows it to move in an appropriate way.
36
What is the top layer of degraded organic material of soil?
Humus
37
What is humus?
leaf litter and worms
38
Why are grasslands the most productive biome?
The abundant top soil, and it doesn't rain as much. Too much rain will leach out soils.
39
What is soil degradation?
It occurs when the things that contribute fertility are removed and not replaced, and the conditions which support soil fertility are not maintained.
40
What are causes of soil degradation?
A. Poor cropping practices
| B. Erosion
41
Why are poor cropping practices causes of soil degradation?
mono-cropped agriculture (one variety of plant will use the same requirement for mineral resources) and if we keep cropping that plant, the mineral content in that area decreases
42
Why is erosion a cause of soil degradation?
becomes a problem because when we remove a top layer, we expose the soil to the elements
43
How does soil erode from water?
The erosive energy comes from kinetic energy of moving water (through impact of rain and of moving water flowing over surface of soil)
44
What can protect soil from kinetic energy of raindrops?
Thick vegetation - by slowing down the water.
45
Describe the process of soil erosion from wind.
When you plow up grasslands, you are exposing the soil to wind. This is what happened with the Dustbowl.
46
How can you prevent soil erosion?
1. Sloped areas - leave under vegetative cover
2. "Contour Farming"
3. "Terrace Farming"
4. "Windbreaks"
47
What is Contour Farming?
Uses an inner-cropping techniques by planting rows of crops along the contours of landscapes. Water is caught in temporary dams and slow down the rainfall. Usually used with mixed crops, like soybeans and corn.
48
What is Terrace Farming?
Labor-intensive but incredibly productive farms. Maximizing all that you can out of a small piece of land.
49
What are Windbreaks?
Used to prevent wind erosion - leaving trees around the boundaries of your farm.
50
What is Agriculture?
A system of land management used to grow domesticated plants and animals for food, fiber, or energy. It is the process of cultivating land in a certain way with the assemblage of crops and scpae.
51
What was the Neolithic Revolution?
A wide-scale transition of many human cultures from a lifestyle of hunting and gathering to one of agriculture and settlement, allowing the stability to support an increasingly large population.
52
How did the Neolithic Revolution support an increasingly large population?
Through the production of grains, we could have surplus grains. This led the ability to have centralized power structures (Nation-States). Year after year, we would have a surplus of food and this would create the material conditions for more centralized hierarchical power structure.
53
What large company is genetically modifying crops and preventing farmers from "Saving seeds"?
Monsanto
54
What is corn?
a SEED
55
What are "Staple Crops"
Seeds - corn, wheat, rice, soybeans.
56
What is traditional or "non-modern agriculture"?
Types of agriculture that emerged from the agricultural revolution that has dominated civilizations of society - a historical precedence. Still used by a large portion of global population.
57
What is Swidden Agriculture?
"Slash and Burn" - can be very effective and sustainable but requires larger portions of land. Good for low-density areas and soils that are not very rich or deep in topsoil.
58
What is another term for Swidden Agriculture?
"Shifting Cultivation"
59
Where is Swidden Agriculture popular?
Tropical Areas
60
What is the most efficient form of agriculture in terms of labor and crop yield?
Slash & Burn
61
What is the burden of Modern Agriculture?
It requires an increased amount of inputs (fertilizers, pesticides) and we need a certain amount of land and economies of scale for it to work.
62
Why is genetic diversity important?
In modern agriculture, we want YEILD. We are producing corn with larger and better seeds. By spreading out VARIETIES of crops, you are guaranteeing that one of the crops will work. It has to do with the people who use them and HOW they use them.
63
What are simplified agricultural crops?
Potatoes
64
What was the 1970 Southern Corn Blight?
At least 80% of the corn in the US was susceptible to the blight because it contained an adaptation that made it more susceptible to a damaging fungus, so a large portion of the crop was lost.
65
What has happened with farms since the establishment of industrial agriculture?
The amount of farmers in the US has decreased, the number of farms has decreased from 7 million to 2 million. There are less farms, but the farmers are BIGGER. The farmers have to have larger amounts of land to be successful.
66
What are economies of scale?
The bigger farms the you have, the cost of production per unit of corn goes down. You can sell the corn at a lower rate; the profit comes from VOLUME, not a high price of corn. Thus to compete as a family farm, you need a large volume of crops.
67
Where is the increased productivity in agricultural farming coming from?
New types of corn varieties that produce more corn: when they are given ideal conditions of nutrients and phosphorus in controlled settings.
68
What is corn most used for in the US?
It goes into a larger system of food production; livestock, meat, corn syrup, etc.
69
What percentage of energy is lost in the cattle that is contained in the corn?
60%
70
What are the Macro Nutrients in plants?
Nitrogen, Phosphorus, Potassium. They need these in large amounts.
71
What are the Micro Nutrients in plants?
Calcium, zinc, iron. These are small vitamins.
72
What is Liebigs Law of the Minimum?
Plant growth is controlled NOT by the total amount of resources available, but by the availability of the SCARCEST resource (or the limiting factor). Growth is limited by what the limiting factor in that environment is; i.e. copper if you have no copper in a field.
73
What are the high yields in modern agriculture brought about by?
High inputs.
74
What is Guano?
bird poop that creates nitrogen, phosphate and potassium. It has been on the rise in organic farming.
75
Plant growth is NOT controlled by the amount of resources available, but by...
The scarcest resource, or the limiting factor.
76
What are High Yield Seeds?
They are raising the "minimums" by artificially creating the conditions that they demand abundant inputs. We are modifying the structure of seeds such that they will only grow very well IF and THEN they have all of the maximum input. Why we need fertilizer.
77
What are pesticides?
In a diverse natural ecosystem, insect predators/disease/parasites usually keep harmful species under control. Many species usually have adaptations for dealing with them.
78
What are the problems with pesticides?
1. They are broad (we don't have the target to kill SPECIFIC things)
2. Persistent Herbicides
3. Non-Persistent Herbicides
79
What is the problem with pesticides being broad?
It results in herbicide-resistant weeds and insects.
80
What is the problem with pesticides being persistent?
Biomagnification: certain pesticides concentrate in fatty tissue things that eat plankton and end up consuming high concentration of DDT
81
What is the problem with pesticides being non-persistent?
They must be very strong
82
What is the "Terminator Gene" in crops?
Seeds that come out of this crop will NOT reproduce, thus forcing farmers to buy from new seed companies every year.
83
What has the highest pesticide residue?
Apple.
84
What is the key property of water?
Polarity: atoms share protons and electrons UNEQUALLY
85
What is the WHO estimate of the world's population that does not have access to safe drinking water?
25%
86
What percentage of the world's water is fresh water?
2.5%
87
What percentage of the world's fresh water is groundwater? Ice caps/glaciers? Lakes/rivers/soil moisture?
.5% - groundwater
1.97% - ice caps/glaciers
.03% - lakes, rivers, soil moisture, atmosphere
88
What consists of Surface Water?
Ponds, lakes, streams, soil in plants.
89
What is Groundwater?
Falls into the soil and may be taken up by plants or flows on the surface of the ground to join creeks and rivers OR permeates underground.
90
What are key sources of water for irrigation?
Confined vs. Unconfined Aquifirs
91
Why is the water more salty than it ever was?
Evaporation
92
At a global scale, what uses the MOST amount of fresh water?
Agriculture
93
In agriculture, what is water primarily used for?
Irrigation
94
What do precipitation patterns depend on?
Moisture supply and something to trigger condensation and precipitation (storms, fronts, mountains)
95
What does Evapotranspiration Patterns depend on?
Sunshine, temperature and wind.
96
What are human impacts on the Hydrological cycle?
Compounding the problem is the creation of impervious surfaces: asphalt, concrete, and other substance that prohibit the infiltration of water into the soil.
97
What is the drainage basin?
An area in which all rainfall drains toward a common outlet.
98
When precipitation hits the ground, what two paths can it follow?
Runoff (flows over the surface into streams and rivers which make their way to the ocean or to an inland sea) and Inflitration
99
What happens on coastal arbor towns as a result of irrigation?
They are deserted; i.e. the Aral Sea is an example of the depleting surface water resources.
100
What is the Ogallala Aquifier?
One of the largest aquifers in the world. It supplies drinking water for 80% of 2.3 million people who live in the High Plains. Irony of the Dustbowl - farmers were hoping for rain, but they were actually sitting on one of the world's largest aquifers.
101
What are Point Sources of agriculture and water pollution?
"End of the Pipe" discharges: factories, sewage treatment plants, mines, oil wells, oil tankers
102
What are Non-Point sources of agriculture and water pollution?
Acid decomposition, substances picked up by runoff, seepage into groundwater
103
What is a strategy to manage non-point sources of pollution?
Leave buffer strips of vegetation to allow plants or wetlands to filter what is coming through that wont run off directly into waterways
104
What is the Atmosphere?
A collection of gases that gravity holds in a thin envelope around the earth. The temperature and composition vary with altitude.
105
What is the Atmosphere Composition?
Air that surrounds us is 78% Nitrogen, 21% Oxygen, .93% Argon, and .04% Carbon Dioxide.
106
What are the layers of the atmosphere and which layer do we live in?
Troposphere (we live)
Stratosphere
Mesosphere
Thermosphere
107
What is tropopause?
The Circulation of the air stops
108
What is the Ozone?
The ozone layer or ozone shield refers to a region of Earth's stratosphere that absorbs most of the Sun's UV radiation.
109
What is the difference between Stratospheric Ozone and Tropospheric Ozone?
Stratospheric Ozone protects us from the sun's radiation, the Tropospheric Ozone protects us from Urban Smog
110
What are natural sources of Air Pollution?
Volacanoes, dust storms, Blue Ridge Mountains (tree life emits isocreme- protects leafy matter from harmful sunlight)
111
What are the EPA six criteria pollutants?
```
Particulate matter
Sulfur Oxides
Nitrogen Oxides
Carbon Monoxide
Ozone
```
112
Where does pollution come from: Particulate Matter?
industries, motor vehicles
113
Where does pollution come from: Sulfur Oxides?
From electric power plants and industries
114
Where does pollution come from: Nitrogen Oxides?
Motor vehicles, industries, heavily fertiziled farmland
115
Where does pollution come from: Carbon Monoxide
Motor vehicles, industries
116
Where does pollution come from: Ozone?
Formed in atmosphere
117
What are Primary Pollutants?
Things that WE put into the air that are themselves harmful
118
What are Secondary Pollutants?
They emerge at the intersections when the pollutants go into the earth (unstable, quick to react, with the energy of the sun - they change form)
119
What is "Residence Time in Atmosphere and Scale of Impact"?
Certain chemicals do not stay in the air very long (they are taken up, transformed). The Tropospheric Ozone stays a little longer. Carbon Monoxide stays even longer. Certain chemicals stay forever like Carbon Dioxide and CFCs (root cause of depletion of Ozone in Stratosphere).
This plays into political feasibility and action: it is harder to get a political agreement when you are working in the global arena on an issue like Climate Change.
120
What is Urban Smog?
"Smoke" + "Fog"
121
What marked a shift in the attitude around impacts of smog on human health?
Donora PA: 1948 Smog Event where people woke up there was no sunlight for 4 days. When smog lifted, 20 people had died and 1,000 were left ill.
122
What kind of smog exists in LA?
Photochemical smog
123
What is thermal invasion?
Normal: sun rises and warms the surface of the air, warm air at the bottom rises and pollutants are carried away with the wind.
Thermal invasion: cold air on the surface with warm air above it - this warm air TRAPS the pollutants
124
What is "Clean Coal"?
Clean from sulfur (not talking about carbon or how we mine coal)
125
What is causing the hole in the Ozone Layer?
Chlorofluorocarbons (CFCs), or FREON: CFCs are produced by chemical industries for use as refrigerants, solvents, and propellants - each free atom of Chlorine can destroy 100,000 Ozone Molecules. THe properties that we have from Ozone is because of the 3 atoms of oxygen.
126
What was the Montreal Protocol?
In 1987, an international agreement that reduced the production and sale of CFCs.
127
What are some sources of indoor air pollution?
Combustion of sources such as oil, gas, kerosene, coal, wood, tobacco.
Building materials and furnishings.
Wet or damp carpet.
Household cleaning products.
Radon, pesticides, outdoor air pollution.
128
What is the risk of Radon exposure?
Responsible for 20,000 lung cancer deaths each year. Health hazard with a simple solution.
129
What is the "Ultraviolet Century"?
1970 - 2070
1-2 Million extra cases of skin cancer
small amount of CFC progressively created a seasonal ozone hole over Antarctica.
The Ozone hole will not return back to normalcy until at least 2070.
130
What is Acid Rain and how does it impact plant growth?
Plants need a certain amount of pH - the greater amount of Hydroxide or Hyrdogen Ions, the nutrients leach out and plants cannot grow. When you take particles like Sulfur Dioxides and Nitro-dioxides, they enter the atmosphere and it starts to rain, drastically reducing pH levels.
131
What is the basic cause of Climate Change?
It is an increase in carbon dioxide concentrations in the atmosphere - as the carbon dioxide increases, global temperature increases.
132
What is the average global temperature rise over the past 100 years?
.75 degrees Celsius
133
On a global scale, what is the most pressing issue of climate change?
It could drastically impact the global economy.
134
Without greenhouse gases, how much degrees cooler would the earth be?
30 degrees Celsius
135
How is the climate always changing?
Milankovitch Cycles: the earth has gone through 8 glacial, inter-glacial periods. Milankovitch described 3 cyclical variations in terms of the earth's orbit around the sun and how the earth rotates on its axis.
136
What is eccentricity?
The earth rotates around the sun
137
What is obliquity?
The earth rotates on an axis
138
What is precession?
Earth spins as it is rotating.
139
Why is climate change different than this natural cyclical variation?
We are in a geological era of unusual stability: a prolonged warming and stable period between glacial cycles. There has been a direct correlation between the rise of carbon content in the atmosphere and a rise in global temperature.
140
If soil retains too much water, how can you drain the water?
Add sand to the soil.
141
The content of carbon dioxide in the atmosphere is the highest in how many years?
Last 800,000 years.
142
The Green Revolution refers to the increase in crop yields in the second half of the 20th century. What did NOT increase along with crop yields?
Total Agricultural land.
143
What will result in the Biomagnification of pesticides?
Persistent Pesticides
144
What is the global composition of water?
97.5% seawater, 2.5% freshwater.
145
What is the order of use in fresh water?
1. agriculture
2. Industrial
3. Domestic
146
What air pollutants comes rom the burning of oil?
Nitrogen Oxide & Carbon Monoxide
147
What air pollutants comes from the burning of coal?
Particulate matter, sulfur oxides, lead
