PART 2: Soils, Groundwater, and Surface Water (30 marks)
Please answer the following questions.
You may wish to answer the following questions and quantitative problems in point form and use diagrams where appropriate. Avoid writing a simple précis or copying the glossary or textbook definitions; otherwise, your mark will be lower.
- Infiltration capacities for three soils are given next. Express each of these capacities in centimetres (cm) per hour. (3 marks)
75 cm in 2 hours i.___ cm per hour
400 mm in 300 minutes ii.__ cm per hour
2.5 m in 10 hours iii.__ cm per hour - In one short paragraph apiece, define and briefly discuss each of the following components of the soil-water balance:
a) Water surplus (3 marks)
b) Storage withdrawal (3 marks)
c) Soil moisture storage (3 marks)
d) Soil-water recharge (3 marks) - In one short paragraph apiece, define each of the following components of the groundwater subsystem:
a) Hydraulic head (3 marks)
b) Transmission (3 marks)
c) Artesian flow (3 marks)
d) Overland flow (3 marks)
e) Drainage basin (3 marks)
PART 3: Quantitative Exercise I—Soil-Water Budgets (20 marks) - For this question, you will graph and interpret soil-water budget data for the following two stations in different parts of British Columbia. Before you attempt this question, review the sections on soil-water budgets and surface water in British Columbia in Unit 6. In particular, re-examine Tables 6.1 to 6.3 and Figure 6.16 in Unit 6.
a) Using the raw data provided for P, Ea, Ep, and T for each month and a value of S for January only, calculate monthly values for G, R, D, and S, and complete the soil-water budget tables for the following stations:
i. Hedley, in the Similkameen Valley of southern British Columbia (Assignment Table 4.1) (5 marks)
ii. Comox, on eastern Vancouver Island (Assignment Table 4.2) (5 marks)
b) Using the tables you have just completed, construct soil-water budget graphs for both stations. Write a brief interpretation of both graphs (no more than 250 words). Be careful how you deal with G (+G, -G), R, and S for the winter and early spring. (10 marks)
c) Submit your completed tables, soil-water budget graphs, and the integrations.
Assignment Table 4.1: Soil-water budget data for Hedley, BC (P, Ea, Ep, and S values in cm, T in degrees C)
P = Ea -G +G +R Ep D S T
January 3.1 0.0 0.0 11.3 –5.3
February 2.4 0.0 0.0 –0.7
March 1.5 1.4 1.4 3.4
April 1.4 2.7 4.4 8.3
May 2.7 4.8 8.2 13.0
June 3.1 5.5 11.0 16.7
July 2.2 4.8 13.5 19.9
August 2.0 3.5 11.9 19.0
September 2.2 2.8 7.4 14.6
October 2.2 2.4 3.6 8.1
November 2.7 0.5 0.5 1.1
December 2.9 0.0 0.0 –2.8
Total 28.4 28.4 61.9 Mean 7.9
Assignment Table 4.2: Soil-water budget data for Comox, BC (P, Ea, Ep, and S values in cm, T in degrees C)
P = Ea -G +G +R Ep D S T
January 17.6 0.4 0.4 30.0 2.2
February 12.6 1.2 1.2 4.0
March 9.7 2.1 2.1 5.0
April 5.8 4.4 4.4 8.0
May 3.5 7.7 8.0 11.8
June 3.6 8.5 9.8 15.0
July 2.8 8.1 11.5 17.4
August 3.2 6.6 10.5 17.0
September 4.3 5.4 7.1 13.7
October 11.3 4.0 4.0 9.2
November 20.1 2.0 2.0 5.3
December 17.8 1.1 1.1 3.5
Total 112.3 51.5 62.1 Mean 9.4
PART 4: Quantitative Exercise II—Stream Discharge (20 marks)
- For this question, graph and then interpret stream discharge data for the following two stations in different parts of British Columbia. Mean, maximum, and minimum stream discharge data (in m3 per second) are provided for the Similkameen River at Hedley (Assignment Table 4.3) and the Oyster River near Comox (Assignment Table 4.4). Choose the scale of your vertical axes carefully so that your graphs clearly show the seasonal differences in discharge.
a) Construct a hydrograph for the Similkameen River at Hedley. (5 marks)
b) Construct a hydrograph for the Oyster River near Comox. (5 marks)
Assignment Table 4.3: Monthly mean, maximum, and minimum discharge for the Similkameen River at Hedley, BC (values in m3 per second)
J F M A M J J A S O N D
Mean 4.4 5.0 6.7 57.4 153.0 106.0 29.2 8.6 5.9 10.7 16.4 11.6
Max. 5.4 6.4 8.0 127.0 413.0 162.0 54.5 13.2 9.7 31.4 46.0 21.1
Min. 2.8 2.4 5.7 7.2 60.0 53.2 12.3 5.4 4.5 5.5 9.8 5.0
Assignment Table 4.4: Monthly mean, maximum, and minimum discharge for the Oyster River, BC, at its mouth (values in m3 per second)
J F M A M J J A S O N D
Mean 8.2 9.6 10.9 20.4 23.7 18.9 9.0 3.6 2.0 3.2 18.5 15.6
Max. 25.8 25.4 19.2 41.1 47.0 33.4 12.2 5.2 2.7 8.2 70.0 43.2
Min. 2.7 3.4 6.0 9.3 12.6 10.6 5.4 2.6 1.5 1.7 7.8 4.9
c) Write a short interpretation of each hydrograph (150–200 words or one page for each hydrograph), and focus on: (5 marks)
· Explaining the annual trends in discharge.
· Commenting on the differences between mean, maximum, and minimum discharge.
· Comparing the two hydrographs for differences and similarities.
d) Comment on any relationship that you can discern between the annual soil-water budgets of Hedley and Comox (Part 3) and the hydrograph for each of the two stations. This part of your answer should be no longer than 150 to 200 words. You may reference key differences between climates. (5 marks)
e) Submit both hydrographs, and your interpretations and commentaries on the relationship between the hydrographs and the soil-water budgets.
PART 5: Review of Units 5 and 6 (20 marks)
Answer one of the following questions.
- Explain, with examples, how air mass characteristics and source regions can be used for classification of climates. Your answer should be about 500 words.
(20 marks)
This is the end of Assignment 4. If you are following a 15-week schedule, you should submit this assignment no later than the end of Week 10.
Sample Solution