Students in Thailand did fieldwork to investigate the effects of urban sprawl taking place around their school. One group of students measured variations in water pollution in local lakes, and did an environmental quality survey in areas near the school. They concentrated their investigation on the following hypotheses: Hypothesis 1: Lakes are more polluted in areas where housing has been there longer. Hypothesis 2: The overall quality of the environment is better in the older housing area. The students selected three sites in different areas around their school to do their fieldwork. They are described in Table 8.1 below. Table 8.1 Site 1 | an area of older, more expensive housing on a secure estate Site 2 | an area of modern, cheaper housing alongside a main road Site 3 | an area where new housing was being completed

1. (a)What is meant by urban sprawl?[2]
2. (b)To investigate Hypothesis 1 the students did two tests to measure the pH value and clarity of the water. These two tests are described in Fig. 8.1 (Insert), which is taken from a student's fieldwork notebook. Suggest why the method to measure pH may be more reliable than the method to measure clarity.[2]
3. (c)(i)The results of the tests are shown in Tables 8.2 and 8.3 (Insert). Plot the average pH value of the water at site 2 on Fig. 8.2 below. [Figure 8.2][1]
4. (c)(ii)Plot the average depth of clear water at site 2 on Fig. 8.3 below. [Figure 8.3][1]
5. (c)(iii)What conclusion would the students make about Hypothesis 1: Lakes are more polluted in areas where housing has been there longer? Circle your decision below and support it with evidence from Figs. 8.2 and 8.3 and Tables 8.2 and 8.3. Hypothesis is true | Hypothesis is partly true | Hypothesis is false[4]
6. (c)(iv)Look again at Table 8.1. Suggest reasons to explain why the level of water pollution varies between the three sites.[2]
7. (d)(i)To investigate Hypothesis 2: The overall quality of the environment is better in the older housing area, the students did an environmental quality survey at each site. Their survey sheet is shown in Fig. 8.4 (Insert). The decisions made by two students about buildings at the same site are shown in Fig. 8.5 below and opposite. Student A Site number surveyed: 2 Students' decisions on environmental quality Positive description | +2 | +1 | 0 | -1 | -2 | Negative description Buildings in good condition | ✔ | | | | | in poor condition well-designed / attractive | | | | ✓ | | poorly designed / ugly well maintained | | | ✓ | | | poorly maintained no vandalism or graffiti | | | | | ✓ | extensive vandalism or graffiti [Figure 8.5] Student B Site number surveyed: 2 Positive description | +2 | +1 | 0 | -1 | -2 | Negative description Buildings in good condition | | ✓ | | | | in poor condition well-designed / attractive | | | ✓ | | | poorly designed / ugly well maintained | | | | ✓ | | poorly maintained no vandalism or graffiti | ✓ | | | | | extensive vandalism or graffiti Suggest two reasons why the decisions made by the two students are different.[2]
8. (d)(ii)Suggest two ways the group of students could have organised themselves to make sure that their results were reliable. Give a different reason for each way you suggest. Suggestion 1 | Reason Suggestion 2 | Reason[4]
9. (d)(iii)Fig. 8.7 (on page 27) shows the results of the environmental quality survey at the three sites. Use the information in Fig. 8.6 below to plot the results for general features at site 2 on Fig. 8.7. Positive description | +2 | +1 | 0 | -1 | -2 | Negative description General roads and pavements are well maintained | | | ✓ | | | roads and pavements are poorly maintained few road signs or advertising boards | | | | | ✓ | lots of road signs and advertising boards lakes and streams are clean | | | | ✓ | | lakes and streams are dirty lots of insects and wildlife can be seen | | | | ✓ | | no evidence of insects and wildlife [Figure 8.6][2]
10. (d)(iv)Fig. 8.7 shows that the score for condition of the buildings was the same at sites 1 and 2. Identify one other description of the buildings which also had the same score at sites 1 and 2.[1]
11. (d)(v)Use data from Fig. 8.7 to calculate the difference in the total score for the Open space category between Sites 1 and 3.[1]
12. (d)(vi)What conclusion would the students make about Hypothesis 2: The overall quality of the environment is better in the older housing area? Support your decision with evidence from Fig. 8.7.[4]
13. (e)The students did the same environmental quality survey at another local site which had not been developed and was still covered by trees and bushes. Their completed survey sheet is shown in Fig. 8.8 (Insert). Suggest reasons for the positive scores given by the students for this site on Fig. 8.8.[4]

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