Hydrological Research fieldtrip

The Scenario The University of Philippines are asking ISM to form a survey team to gather data about the condition of the river and surrounding vegetated area in the Novoliches Watershed Reservation, Quezon City. Bantay Kalikasan and UP are concerned about the land use conflicts in the area, as human encroachments such as squatters establish themselves in the area. Squatters burn vegetation and clear areas of land and pollute the soil and rivers, which has a negative impact on the natural environment. There is a real concern that these actions will increase the likelihood of flooding put those people in danger.

The Research Question Human encroachments within the drainage basin of the Ilog river will result in an increased likelihood of flooding….. “Should villagers build a squat in this area? what impacts would this have on this part of the watershed, and how their families likely to be effected”

Negative Impact on People Human encroachments within the drainage basin of the Ilog river will result in an increased likelihood of flooding Impact of human encroachments: Negative Impact on Environment

What is a hypothesis? A tentative explanation that can be tested by further investigation.

Assessment Medium: Group report Major: SAQ in class test – Sort Answer Questions

Location of site – see maps….

Infiltration, Diversity & coverage in Vegetated area Diversity & Coverage & Infiltration in Sparsely vegetated area (A)The Vegetation Site

Area for Vegetation, soil & water pH measurements Abundance & Diversity measurements (B)The Biodiversity Site

The transects for groups measurements in the stream, for wetted perimeter, cross sectional area & velocity & boulder size (C) The River Processes Site

(a) Essential Question: What is the impact of the vegetation on the hydrological cycle within the drainage basin and how do changes in the vegetation affect the cycle? 1) Soil Infiltration: Using an Infiltrometer in a densely and sparsely vegetated area 2) Vegetation Diversity: The number of different types of species in a quadrant placed in a densely and sparsely vegetated area these are measurements of the soils hydraulic conductivity 3) Vegetation Coverage: The % vegetation coverage in a quadrant placed in a densely and sparsely vegetated area 4) Vegetation Height: Highest vegetation in center square of quadrat (A) The Vegetation Site

(b) Essential Question: What is the overall environmental quality of the area? And to what extent has the area been affected by human activity? 1)Diversity of Species: The number of different species found each time a net sample is taken 2)Abundance of aquatic life: The Total number of organisms found each time a net sample is take 3)Water and, Soil & Plant PH – using a PH sensor (acidic or alkali) (6.5 to 8.0 alkaline is the optimum for fresh water) (B) The Biodiversity Site

(c )Essential Question: What are the key river processes and what do these tell us about flooding and flood risk in the past, now and in the future? 1) The Wetted Perimeter: Measured using a weighted tape measure at different points in the river bed 2) The Cross Sectional Area: Measurement of the width of the river divided by the average depth measured using a ruler at spaces of 50cm apart and averaged (or then plotted on a chart, and the cross sectional rectangles are then totaled) 3) Hydraulic radius: A measure of channel efficiency, calculated by dividing the cross sectional area by the wetted perimeter (more efficient channels are less likely to flood) 4) Velocity: Measured using a velocity meter (at 60% of river depth), or timing how long it takes for a piece of cork to move 5 meters on the surface (5 trials) 5) Discharge: in cubic meters per second, calculated by multiplying the velocity by the cross sectional area 6) Size of large boulders transported during flooding: Using a Transportation Curve (Hjulsrom, 1935), it is possible to estimate the velocity of stream required to transport the large boulders on the river bed, from this the discharge of the river during flooding can be estimated – measurement of boulder diameter is required (largest boulder in each cross section) *Cross sectional area of the flooded river is also required (C)The River Processes Site

Hypotheses…… Hypotheses (a) Human encroachments will lead to reduced vegetation cover and diversity and changes in infiltration rates (b) There is a seasonal difference in the environmental quality of the area. The areas is clean and free from human encroachments. (c) The river Ilog has the potential to flood the entire area (through a comparison of river as it is now and during flooding)

Fieldtrip preparation You will work in groups of 5 and your groups will familiarize yourselves with the three areas of data collection The aim of this session is to create & familiarize yourself with the equipment you will be using on the fieldtrip Develop hypotheses from (a) (b) (c)

Tape Measure this will be used to measure the cross sectional area of the stream and the wetted perimeter Take the depth every 50 cms to get the average To measure the wetted perimeter this will be weighed down with rocks

Inflitrometer A ruler is used to monitor how much time it takes for 5 cms of water to infiltrate Data will be recorded on the data sheet

Infiltration rates: Vegetated area Put 5 centimeters of water in the infiltrometer and time how long it takes to infiltrate into the soil on a dense and sparsely vegetated area. The dense area represents an area without human encroachments & the sparse area represents and are where they have been human encroachments. Level of water Time taken In Inflitrometer to infiltrate 5 cm … cm ……….. 3 cm ………… 2 cm ………… 1 cm ………….. 0 cm ………….. Total time taken: ________ (minutes) To find out the average infiltration rate of your soil divide 5cm by the total time taken, this will give you the average rate in cm per second Average infiltration rate in vegetated area: ________ (cm/min)

Infiltration rates: Sparse area Put 5 centimeters of water in the infiltrometer and time how long it takes to infiltrate into the soil on a dense and sparsely vegetated area. The dense area represents an area without human encroachments & the sparse area represents and are where they have been human encroachments. Level of water Time taken In Inflitrometer to infiltrate 5 cm … cm ……….. 30 cm ………… 2 cm ………… 1 cm ………….. 0 cm ………….. Total time taken: ________ (minutes) To find out the average infiltration rate of your soil divide 5cm by the total time taken, this will give you the average rate in cm per second Average infiltration rate in sparse area: ________ (cm/min)

Measuring velocity Using Cork, measure the velocity of the stream (in the middle of the stream), by timing how long the Cork takes to travel 5 meters Do this 5 times and work out the average velocity= distance time

Wetted perimeter & velocity Wetted perimeter of stream _______ meters Velocity of the stream = Trail 1 = ____seconds Trail 2 =____seconds Trial 3 = ____seconds Trial 4 = ____seconds Trial 5 = ____seconds Average _____ seconds to travel 5 meters The stream velocity in meters a second ______ velocity= distance time

Measuring the Cross Sectional Area 1.To measure the cross sectional area of the stream, – hold the tape measure to the bank at each end – this will allow you to measure the width of the stream, 2.To measure the depth divide the stream into verticals – these will be every 50 cms 3.You will then use the meter stick to the depth of the stream at each vertical 4.Average these out and then times this by the stream width to get the cross sectional area

1.Put in the other verticals (50 cm away from each other – the first two are marked), and record the depth midway between each one 2.Number of verticals …….. 3.Average depth………. 4.Cross sectional area (average depth x width) ………cm 5.Hydraulic radius =………………… 6.Long axis of largest boulder= ……….. Width……………… Depth of vertical A)……… Depth of vertical B)……… Measuring the cross sectional area & hydraulic radius

Boulder size Record the long axis of the largest boulder on your transect Largest boulder

Boulder Size Using a Transportation Curve (Hjulstrom, 1935), it is possible to estimate the velocity of stream required to transport the large boulders on the river bed, from this the discharge of the river during flooding can be estimated Measurement of long axis of largest boulder is required (largest boulder in each cross section)

The Hjulstrom Curve…….

Erosion, Transport & Deposition The Hjulstrom curve is used to estimate the velocity needed for erosion, transportation, and deposition Analysis: 1) A particle of sediment sized 10mm would be eroded by a river velocity of 500cm/sec TRUE / FALSE 2) A particle of sediment 10mm would be transported by a river velocity of 90cm/sec TRUE / FALSE 3) A particle of sediment 0.01 would be eroded by a river velocity of 10cm/sec TRUE / FALSE

Vegetation diversity, coverage & height in Vegetated area Diversity Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average no of species…….. Coverage Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average % cover…….. Measure vegetation diversity by throwing the quadrant to your feet randomly, and counting the Number of different plant specie in the quadrat – in a sparse area to represent where there are human encroachments and a dense area to represent where there have not been human encroachments Vegetation coverage/density will be recoded by eyeballing and estimating the % coverage on a sparsely and a densely vegetated area. To measure the height of vegetation measure the highest piece of vegetation from the center square of the quadrat and record its height in cm using a small ruler Height Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average Height (cm)……..

Vegetation diversity, coverage & height in Sparse area Diversity Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average no of species…….. Coverage Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average % cover…….. Height Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average Height (cm)…….. Measure vegetation diversity by throwing the quadrant to your feet randomly, and counting the Number of different plant specie in the quadrat – in a sparse area to represent where there are human encroachments and a dense area to represent where there have not been human encroachments Vegetation coverage/density will be recoded by eyeballing and estimating the % coverage on a sparsely and a densely vegetated area. To measure the height of vegetation measure the highest piece of vegetation from the center square of the quadrat and record its height in cm using a small ruler

The environmental health of the area We can record the number of different species we find in the river We can also record the total amount of life we find in the river (abundance) as well at take not of the names of the different species This will be done over 5 trials, holding the net in the water for 30 seconds, and seeing how many species come into the net, lightly disturbing the bed of the river in front

Vegetation, soil & water pH pH is a measure of acidity and basicity (alkali) Using the Litmus paper record the PH on the soil on the bank, in the river channel and on a vegetated area For aquatic life the pH should be between 6.0 and 8.5 pH units – what is the pH like at the river? Vegetation pH …………….. Soil pH………………. Water pH……………..

Biodiversity & the environmental health of the area Diversity (number of different species) Trial 1….. Trail 2….. Trial 3….. Trial 4….. Trial 5….. Average no of species per trial…….. Total no of species…….. Abundance (of living organisms) Trial 1 Trail 2 Trial 3 Trial 4 Trial 5 Average no of living organisms per trial …… Total no of living organisms….. Abundance & diversity is measured by holding the net in the river for 30 seconds and lightly disturbing the bed of the river in front Use the litmus paper to get this data: 1)Vegetation pH …………….. 2) Soil pH ………………. 3) Water pH …………….. Names & numbers of organisms

1.What is the main reason for carrying out this research? 2.What is the wetted perimeter? 3.How do you measure the wetted perimeter of an irregular shaped stream with rocks and boulders in the channel? 4.How do you measure the wetted perimeter of a rectangular shaped stream? 5.How can we predict the velocity needed to transport large boulder? 6.How do we measure infiltration rates? 7.How do human encroachments influence the soil & vegetation in the drainage basin? 8.On the geography fieldtrip, you will be studying the river …….. 9.What is the name of the protected area of land you will be visiting? 10.What are the names of the organizations we will be working with on the fieldtrip? 11.What road will we take to get to the watershed? 12.Why is the watershed so important for metro manila? Why does it need to be protected? 13.How do you calculate the discharge of a river? 14.How do you calculate the hydraulic radius of a river? 15.How do you calculate the average depth of a river channel? 16.How do you measure the velocity of a stream? 17.What does the hjustrom curve allow you to do? 18.What instrument do you use to examine vegetation diversity & coverage? 19.What instrument do you use to examine vegetation height? 20.How do you check whether soil, water or vegetation is acidic or alkali? 21.How many data collection ‘stations’ will there be on the fieldtrip? 22.List all the data collection equipments you will be using? 23.List all the data you will collect 24.What time does the bus leave to go to the watershed? 25.What should you bring with you? Answer in your groups – questions to check your understanding

Homework Review all data collection methods (on wiki) s+Watershed+Fieldwork (block H) s+Watershed+Fieldwork s+Watershed+Fieldwork (block A) s+Watershed+Fieldwork Complete river channel calculations

checklist 1.Packed lunch am arrival – ES Dropoff 3.Lots of water to drink 4.Pencil 5.Stopwatch/ calculator 6.Camera – at least 1 in group 7.Raincoat 8.Laptop (totally optional & your responsibly – max 1 per group) 9.Change of footwear – so you can go in the river channel

Environmental health data from Sept 24 th 2009 No of species found in river : 5 species (Shrimps, crabs, nymphs, water striders, Fish) Average no of species found per sample: 3 Average no of organisms found: 7 PH in Water: 7 PH on Soil: 6 PH on Vegetation: 6

Environmental health data from Feb 19 th 2010 No of species found in river : 5 species (Spider, Crab, Water strider, Snail, Unknown bug) Average no of species found per sample: 2 Average no of organisms found: 3 PH in Water: 8 PH on Soil: 6 PH on Vegetation: 6.5

Potential Cross Sectional Area and Velocity of the stream If you are estimating the potential discharge in a flood, the cross sectional are of the area that floods (as high as the bridge) is 39 square meters (3 meters in height and there is a width of 13 meters), The largest boulder was 1meter in length – use the Hjulstrom Curve in to calculate the potential discharge.

Negative impact of human encroachments on the environment Pollution of the river Less vegetation interception Habitat of the animals will be destroyed Animals (chicken, goats) could clear land Trees could be cut down Squatters will clear areas of land (burning) Soil on the river banks will not be anchored by vegetation Pollution of river, contamination from human chemicals, waste/sanitation Loss of vegetation due to usage by humans Loss of habitat/wildlife Potential forest fires Flooding - More soil erosion, no vegetation to absorb/transpire and intercept water or to stabilize soil leading to potential mudslides, desertified (no more nutrients) Building dams Soil flowing into river Plastic, waste and other human material pose negative effect on wildlife Bringing in livestock, affecting balance of habitat, consuming vegetation/Interspecies breeding

Negative impact of human encroachments on the people – If the vegetation is cleared, the area is more likely to flood Cutting down trees can cause landslides Overall water supply to MM would be in danger Move houses because of flooding. Clear land to farm crops. More of the watershed would need to be cleared to form paths. Move houses because of flooding. Clear land to farm crops. More of the watershed would need to be cleared to form paths.

Hydrology & River landforms: Test review questions 1.What is a meander? how is it labeled? 2.What is a flood hydrograph, how is it labeled and what does it tell us about a flood risk within a drainage basin? 3.Explain the transportation and erosion processes 4.Explain how the cross sectional area, discharge and hydraulic radius of a river are calculated 5.Explain how the Hjusltrom curve allows us to estimate the velocity required to transport and erode the rivers load 6.What is the relationship between vegetation and flood risk? 7.A Hypothesis is “a tentative explanation that can be tested by further observation/ experimentation”, give an example of a geographical hypothesis you used on your fieldtrip 8.Describe the methodology you used to measure the wetted perimeter in the river: 9.Describe the methodology you used to measure the river velocity in the river: 10.Describe the methodology you used to measure the cross sectional area in the river: 11.When you where measuring the velocity of the stream, did you get similar data on each trial? Suggest reasons why there were variations in the data you collected: 12.Evaluate (give the strengths and weaknesses) of the methodology used to collect your data during the fieldtrip 13.Summarize the conclusions of your investigation.