Lesson 1-3 Flashcards
1
Q
It is a land bounded by a topographic divide which intercepts, stores and directs rainwater to a stream or river system down to a common outlet.
A
Watershed
2
Q
The common outlet is knows as ________ either a lake, sea or ocean.
A
Mouth
3
Q
A divide refers to surface divide (top of mountains)
A
Topographic divide
4
Q
It refers to underground divide or rock formations.
A
Phreatic divide
5
Q
Importance of watershed
A
- Provide water for agricultural, industrial, domestic purposes (essential to economic progress and stability)
- Provides Timber, Forage, wildlife
- Provide services like aesthetic and protective.
6
Q
Anthropogenic activities that causes man-made calamities such as sedimentation and siltation.
A
- Kaingin
- Illegal logging
- Improper farming practices
- Forest fire
- Grassland burning
- Improper range management.
7
Q
The country nowadays is encountering different man-made calamities that include ____ and ____ due to ____ ____.
A
siltation, sedimentation, soil erosion
8
Q
A watershed is composed of the following resources:
A
water, soil, vegetation, rock, minerals,
flora and fauna, human and improvements.
9
Q
Largest basins in the Philippines
A
- Cagayan Cagayan Valley 2,569,648
- Mindanao S. Mindanao 2,315,900
- Agusan N. Mindanao 1,092,100
- Pampanga C. Luzon 975,900
- Agno Luzon 595,200
- Abra Ilocos 512,500
- Pasig Laguna 467,800
10
Q
Drainage area of Cagayan River Basin
A
2,569,648 (2.5 m)
11
Q
Drainage area of Mindanao in S. Mindanao
A
2,315,900 (2.3 m)
12
Q
Drainage area of Agusan in N. Mindanao
A
1,092,100 (1.0 m)
13
Q
Drainage area of pampanga in C. Luzon
A
975,900
14
Q
Drainage area of Agno
A
595,200
15
Q
Drainage area of Abra
A
512,500
16
Q
Drainage area of Pasig laguna
A
467,800
17
Q
Where is the head of Agno River Basin?
A
Loo, Bugias
18
Q
Agno river basin’s mouth or outlet is in ____ ____
A
Lingayen Gulf in Pangasinan
19
Q
Agno river basin traverse towards the municipalities of ____ to Ambuclao dam in ____ and Binga Dam in ____, Benguet
A
Kabayan, Bokod , Itogon
20
Q
Stream that has water just after rainfall
A
Ephemeral Stream
21
Q
Stream that has water only during the rainy season
A
Intermittent stream
22
Q
Stream that has water all through-out the year
A
Perennial stream
23
Q
The world has only __ forest cover; __ relatively undisturbed (frontier forest); __ of frontier forest threatened;
A
30%, 40%, 39%
24
Q
____ of the ___ watersheds of NIA with total area of 3,968,805 ha are in critical conditions;
A
83% of the 114
25
the 4.7 million hectares (total area) NIA watersheds, only __ of it is covered with ____, the rest are (__), (__), and (___).
F31%, GL31%, CL37%, BU1%
26
____ out of 73 provinces have over half of their land area being moderately to severely eroded
13
27
The estimated annual rate of soil loss in the country is _____ million tons.
74-81
28
Between_______ of the country’s land area are affected by soil erosion;
63-77%
29
__ river systems in Luzon are reported dead or dying. __ reported dead by EMB
29, 10
30
It implies the control or manipulation of watershed to carry out planned activity aimed at attaining, specific objectives.
Watershed Management
31
Refers to the management of all-natural resources of a drainage basin to protect, maintain and improve water yield.
Watershed Management
32
Triangular concept of Watershed Management
Sustainable Yield, Protection/ Conservation, Rehabilitation/ Restoration
33
Watershed problems
1. Soil Erosion
2. Loss of Biodiversity
3. Declining land/ site productivity because of fertility decline
4. Microclimate deterioration
5. Low water quality and quantity
34
____ million tons of soil are lost annually from upland
74-81
35
Benefits from Successfully Manage Watershed
1.Economic Benefits
2. Social services
3. Environmental Services
36
1.Economic Benefits of watershed
a.) Water supply – hydro-electric power production and for domestic use
b) Forestry- Production of forest products
c) Agriculture- crops and livestock production
d) Fishery- aquaculture in reservoir and watershed stream/rivers
e) Mining- quarrying for construction purposes
37
2. Social services
a) Ecotourism- scenic landscape
b) Recreation-mountain climbing, fishing, etc.
c) Historical- protection of historical monuments
d) Cultural- protection of indigenous cultures.
e) Health- Watershed control of water borne diseases that affects human
38
3. Environmental Services
a) Biodiversity- flora/fauna conservation
b) Soil conservation- erosion control
c) Water conservation- retention/storage; quality control
d) Oxygen generation- plants releases oxygen to atmosphere
e) Microclimate amelioration- amelioration of temperature extreme
39
Principles Governing Watershed Management /Development
1. Holistic and Balance Framework
2. Sustainable Management and Development
3. Participatory Approach and Equitability
4. Efficiency and Effectiveness
5. Multi- sectoral and Interdisciplinary Approach
40
an ecosystem, with numerous physical, biological and social components that are intricately related to one another.
Watershed
41
a common property with many stakeholders.
watershed
42
major watershed stakeholders
1. state
2. forest communities
3. LGU
4. water users
5. Forest-based Industry sector
43
The continuous process by which water is transported from the oceans to the atmosphere to the land and back to the sea. (Hydrology Vessmen 1986)
-The hydrologic cycle
44
-The ocean contains ___ water and ___ on land approximately __ of the earth’s water as fresh
water.
96. 5%, 3.5%, 1%
45
Hydrologic cycle is expressed as P=
P=RO+E+T+I+S
46
Solar radiation heats liquid from bodies of water causing gradually change into a gas or water vapor.
Evaporation
47
Factors Affecting Evaporation
a. Solar radiation
b. Temperature/ Relative Humility
c. Volume of available water
d. Vegetation/Soil Cover
e. Soil
48
Results of the reduction of temperature by the removal of latent heat of evaporation resulting to liquid product.
Condensation
49
condensed form of atmospheric moisture of consisting of small water droplets or tiny ice crystals. (range in size from about 5-75 micrometers or 0.0002to 0.003in)
Clouds
50
evaporation of water particles from plant opening or from stomata of leaves.
Transpiration
51
all forms of water deposited on the earth surface and derived from atmospheric vapor.
Precipitation
52
Types of rain gauges
1.) Non recording rain gauges
2.) Recording/ automatic rain gauge
53
Types of Recording/ automatic rain gauge
a.) Weighing recording type rain gauge
b.) Tipping bucket
54
TYPES OF PRECIPITATION
1.) Convective precipitation
2.) Orographic precipitation
3.) Cyclonic precipitation
55
results from excessive heating of the earth’s surface, causing water vapor to rise up condense, coalesce and increase in diameter before they fall as raindrop.
Convective precipitation
56
wind from the sea or ocean blows the condensed nuclei, towards the seashore, the condensation nuclei, coalesce and increase in diameter before they come across physical barriers usually fall as rain the windward direction.
Orographic precipitation
57
precipitation resulting from movements of air masses due to differences in barometer pressure.
Cyclonic precipitation
58
2 Types of cyclonic precipitation
a.) Non-frontal
b.) Frontal
59
low pressure area is –lifted by air masses, followed by cooling and raindrop formation.
Non-frontal
60
opposite air masses with different temperature meet precipitation occurs at the boundaries of the masses.
Frontal
61
silver iodide plus dry ice (solid carbon dioxide) is sprayed into the clouds which attract several small water droplets to come together to form raindrops.
Cloud seeding
62
1. Which creates stronger rainfall and higher soil erosion cold front or warm front?
Cold front
63
2. Which precipitation creates typhoon convective, orographic, or cyclonic precipitation?
cyclonic precipitation
64
What type of rainfall is experienced in forested watershed during summer?
convective
65
What precipitation is occurring on the end and start of rainy season?
Cyclonic
66
Refers to rainfall caught by vegetation or crown of trees
Interception
67
Factors in Influencing Interception
A.) Rainfall intensity, duration, and distribution
B.) Vegetation characteristics
68
Importance of interception
1.) Influences soil moisture distribution
2.) Reduces the type and quantity of precipitation to be converted to overland flow.
69
Types of Interception
1.) Through fall
2. Stem flow
3. Interception loss via evaporation
70
Methods of measurement of interception
1.) Direct method
2.) Indirect method
71
-using rainfall gauges over and under the vegetation, the difference between the two represents the intercepted precipitation.
Direct method
72
by the use of regression equation, given several dependent factors the
interception is estimated.
Indirect method
73
refers to the vertical entry of water from the surface into the soil.
Inflitration
74
Importance of infiltration
Major process that recharges the water table.
75
Factors Affecting Infiltration Capacity
1.) Thickness of saturated layer
2.) Soil moisture
3.) Compaction caused by rain
4.) In wash of fine materials
5.) Entrapped air
6.) Microbial activities
7.) Soil porosity
8.) Land uses – logging, road construction, kaingin, grazing
76
Measurement of Infiltration
a.) areal measurement
b.) point measurement
77
analysis of rainfall run- off data from a watershed.
areal measurement
78
Example of point measurement
Ring infiltrometer (single/double)
79
<1 (mm/hr)
very slow
80
1-5 (mm/hr)
slow
81
20-65 (mm/hr)
moderate
82
65-125 (mm/hr)
moderately rapid
83
125-250 (mm/hr)
rapid
84
>250 (mm/hr)
very rapid
85
refers to water flowing on soil surface as a result of soil saturation.
SRO
86
occurs when rate of precipitation exceeds the rates of which water infiltrates.
SRO
87
Factors affecting SRO
1.) Climate factors
2.) Physiographic factors
88
Physiographic factors affecting SRO
a.) Land use
b.) Area
c.) Shape
d.) Elevation
e.) Slope
d.) Orientation
89
Climate factors affecting SRO
a.) Type of precipitation
b.) Rainfall intensity
c.) Duration of rainfall
d.) Distribution of rainfall on basin
90
Methods of Measuring SRO
1.) Use of run-off plots
2.) Weirs or Flumes
91
It enters the ground water aquifer and then slowly finds its way to streams. (above water table)
Subsurface Flow
92
– water that percolate to a great depth and then appears after long time intervals often as distant points as springs, artesian wells, and geysers (below water table)
Percolation
93
Factors Affecting Percolate
1.) water content of soil
2.) vegetation
3.) depth of soil
94
movement of water under the force of gravity through a defined semi-permanent channel.
Stream flow
95
graphical representation of a stream-flow discharge
Stream flow hydrograph
96
Common units of stream flow discharge in the Standard International (SI) is expressed in
cubic meter per second.
97
Watershed Characteristics that Affects Stream-flow
a.) Size of watershed
b.) b.) Shape of watershed
c.) c.) Channel slope
d.) Drainage density and network
e.) Presence of bodies of water within the watershed
98
Variables that Affect Stream-flow
a.) intensity of rainfall
b.) duration of rainfall
c.) amount
d.) land use
e.) condition of watershed
f.) type of vegetation
99
Importance of Stream-flow
1.) Planning for flood control
2.) Estimating the dependability of water supply
3.) Designing reservoir storage
100
Parts of Stream-flow Hydrograph
1.) Rising limb
2.) Falling limb/recession
3.) Peak flow
101
refers to abrupt or gradual increase in water level in rivers depending on the condition of watershed or intensity of rainfall.
Rising limb
102
refers to either abrupt or gradual decrease in water level in rivers depending on the condition of watershed or intensity of rainfall.
Falling limb/recession
103
refers to the highest water level in the river or stream.
Peak flow
104
graphical representation on the rise and fall of water volume or discharge in a river for certain period of time expressed in cubic meter per second.
Hydrograph
105
Measurement of Velocity
1.) Floatation method
2.) Current meter
106
refers to soil particles that are transported by stream flow
Sediment
107
process of deposition of transported soil particles, gravels and cobbles
Sedimentation
108
total sediment outflow from the watershed
Sediment yield
109
portion of the sediment discharge consist of fie soil particles, such as silt and clay which are transported in suspension.
Suspended yield
110
portion of the sediment discharge consist of sand gobbles and gravels
Bed load
111
bed loads and suspended loads
Total sediment load
112
Mode of Transport
1.) Suspension
2.) Saltation
3.) Bed load
113
- sediments are suspended in water
suspension
114
bouncing sediments
saltation
115
sediments that move constantly in contact with the steam bed.
bed load
116
The process of increase in water quantity or supply
water augmentation
117
The process of replacing water into a stream due to losses from well usage
water augmentation
118
Things to consider in water augmentation
water harvesting
water storage
water coservation
119
120
Types of soil erosion
1. Gully Erosion
2. Raindrop or splash erosion
3. Rill erosion
4. Sheet erosion
5. Streambank erosion
6. Tunnel erosion
7. Mass erosion
121
Forms when drop of rain freezes and winds carry them
Hail
122
Rain that freezes as it falls
Sleet
123
Takes place wherever a river or stream changes course, causing the soil around it to erode.
Streambank erosion
124
Formation of deep chanels that can cause extreme damage
Gully erosion
125
It has minimal effect and occurs when raindrop fall on the soil surface carrying away small particles
Splash erosion
126
It only removes thin layers of top soil that is common in areas with heavy anthropogenic activity.
Sheet erosion
