Soil Lec (2.6)

Question 1

what are the steps in THE HYDROLOGIC CYCLE

Answer 1

1. Evaporation
2. Transpiration
3. Condensation
4. Precipitation
5. Interception
6. Infiltration
7. Runoff
8. Overland Flow
9. Stream Flow

Question 2

what are the two sub processes of precipitation in the hydrologic cycle

Answer 2

• Coalescence Process
• Ice-crystal process

Question 3

conversion of water from liquid to gas

Answer 3

Evaporation

Question 4

True or False

Transpiration is the conversion of water from gas to liquid

Answer 4

False

Correct answer: Condensation

Question 5

loss of water from the plants in the form of water vapor

Answer 5

Transpiration

Question 6

forms of water particles fall from the atmosphere and reach the ground

Answer 6

Precipitation

Question 7

what are the two processes that may occur when the water reaches the ground

Answer 7

1. Some of the water may evaporate back into the atmosphere
2. The water may penetrate the surface and form part of the groundwater

Question 8

the process of interrupting water movement in the chain of transportation events leading to streams

Answer 8

Interception

Question 9

entry of water into the soil

Answer 9

Infiltration

Question 10

True or False

Stream Flow is the total runoff confined in the stream channels

Answer 10

True

Question 11

excess water that does not infiltrate into the soil

Answer 11

Runoff

Question 12

portion of surface runoff that flows over the land surface towards the stream channels

Answer 12

Overland Flow

Question 13

• a geographic unit that collects and drains water into water bodies such as streams, lakes, rivers, or wetlands
• the geographic area in which waters drain downslope along with a drainage outlet to a common basin or lowest point

Answer 13

Watershed

Question 14

Classification of Watersheds by Size (general)

1. large:
2. medium:
3. small size:

Answer 14

1. > 2500 km² or 250,000 ha
2. between 250 km² - 2500 km²
3. < 250km² or 25,000 ha

Question 15

Classification of watershed based on area (specific)

1. Watershed:
2. Sub-watershed:
3. Mili-watershed:
4. Micro-watershed:
5. Mini-watershed:

Answer 15

1. 50,000 – 2,000,000
2. 10,000 – 50,000
3. 1,000 – 10,000
4. 100 – 1,000
5. 10 – 100

Question 16

CHARACTERISTICS OF WATERSHEDS

Answer 16

1. Large Watersheds
2. Small Watersheds

Question 16

Two-phases of runoff generation on large watersheds

Answer 16

1. Land Phase
2. Channel Phase

Question 17

• Well-developed network channel and phase, thus, channel storage is
  dominant
• Less sensitive to short duration and high-intensity rainfalls

Answer 17

Large Watersheds

Question 18

• Have dominant land phase and overland flow; relatively channel phase is
  less conspicuous
• Highly sensitive to short-duration rainfalls which are highly-intense

Answer 18

Small Watersheds

Question 19

True or False

Small Watersheds are less heterogeneous than large watersheds

Answer 19

True

Question 20

are generally exemplified by upland areas where rainfall and runoff depths are higher, and well-developed and an extensive channel outlet is lacking

Answer 20

Small Watersheds

Question 21

CLASSIFICATION OF WATERSHEDS BY LAND USE

Answer 21

1. Urban Watersheds
2. Agricultural Watersheds
3. Forest Watersheds
4. Mountainous Watersheds
5. Coastal Watersheds
6. Marsh/Wetland Watersheds
7. Desert Watersheds

Question 22

an urban watershed is more vulnerable to flooding if the drainage system is inadequate due to ____

Answer 22

increase in runoff

Question 23

True or False

Forest Watersheds have enhanced subsurface flow, and there are times when there is little to no surface runoff

Answer 23

True

Question 24

* a watershed utilized for buildings, roads, streets, parking lots, and pavements * drainage systems are built artificially, so the natural water flow is substantially altered

Answer 24

Urban Watersheds

Question 25

dynamic due to significant land-use changes

Answer 25

Agricultural Watersheds

Question 26

generally steep gradient and low soil porosity, surface runoff is high during rainfall, and flash floods are common

Answer 26

Mountainous Watersheds

Question 27

* are different from that of agricultural or urban watersheds * Its hydrologic behavior is influenced by the type of vegetation present in the area

Answer 27

Forest Watersheds

Question 28

* the hydrologic characteristics are highly influenced by tidal action and backwater from waves * these watersheds receive high rainfall, mostly of cyclonic type, do not have channel control inflow, and are vulnerable to severe local flooding

Answer 28

Coastal Watersheds

Question 29

# True or False **coastal erosion** is a common problem due to wave motion

Answer 29

True

Question 30

* almost flat and are comprised of swamps, marshes, watercourses, and others * wildlife is rich, and the diversity of vegetation is usually observed

Answer 30

Marsh/Wetland Watersheds

Question 31

what is the dominant process in Marsh/Wetland Watersheds

Answer 31

evaporation

Question 32

* this type of watershed is not common in the country * there is a low opportunity for groundwater recharge due to limited rain

Answer 32

Desert Watersheds

Question 33

how many river basins in the philippines

Answer 33

421

Question 34

of the 421 river basins in the country, ____ are classified as major, and ____ are classified as minor

Answer 34

18 ; 403

Question 35

# True or False A major river basin has a drainage area of at least **1,800 km².**

Answer 35

False | Correct Answer: 1,400 km²

Question 36

how many major river basins are located in luzon, visayas, and mindanao respectively

Answer 36

* luzon: 7 * visayas: 3 * mindanao: 8

Question 37

Rank of the basin is based on

Answer 37

magnitude of drainage area

Question 38

erosion is going on in ____ at a rate of 2.45 million m² per year

Answer 38

Ambuklao Dam

Question 39

what are the major river basins & their respective regions

Answer 39

1. cagayan - cagayan valley 2. mindanao - southern mindanao 3. agusan - northern mindanao 4. pampanga - central luzon 5. agno - central luzon 6. abra - ilocos 7. pasig-laguna bay - southern luzon 8. bicol - bicol 9. abulug - cagayan valley 10. tagum libuganon - southeastern mindanao 11. ilog-hilabangan - western visayas 12. panay - western visayas 13. tagoloan - northern mindanao 14. agus - southern mindanao 15. davao - southeastern mindanao 16. cagayan - northern mindanao 17. jalaud - western visayas 18. buayan malungan - southeastern mindanao

Question 40

a complex process intended to protect and conserve our water resources for diverse use

Answer 40

Watershed management

Question 41

____ very important in undertaking watershed management activities

Answer 41

Financial capita

Question 42

WATERSHED MANAGEMENT PROGRAMS

Answer 42

1. Protection 2. Utilization/Functions of Watershed

Question 43

a fire line around watershed areas should have a width of ____

Answer 43

5 m

Question 44

Examples of exotic species

Answer 44

* *Pinus caribbean* * Giant Ipil-ipil * *Albizia falcataria*

Question 45

# True or False man is the **worst enemy** of watershed area

Answer 45

True

Question 46

Utilization/Functions of Watershed

Answer 46

* Important source of water for: domestic use, agriculture, industrial/commercial, and other uses * Site for biodiversity * Hydroelectric Power

Question 47

a practice of using water efficiently to reduced unnecessary water usage

Answer 47

Water Conservation

Question 48

Soil and water conservation measures are predominantly applied for the following purposes:

Answer 48

* To control runoff and prevent loss of soil, by soil erosion * Maintain or to improve soil fertility * To conserve or drain water * To harvest (excess) water