Students from Brazil who lived near Tijuca National Park did some fieldwork to study the tropical rainforest ecosystem. They visited three sites which are described and located in Fig. 7.1 (Insert).

1. (a)The vegetation in the tropical rainforest adapts to the climate. Use arrows to match the vegetation feature with the reason for its adaptation. One has been completed for you. Feature of the vegetation Drip-tip leaves Tall trees Large leaves Buttress roots Reason for adaptation to compete for sunlight to make the tree more stable to remove heavy rainfall to allow more transpiration[2]
2. (b)(i)To obtain data the students made each of their measurements five times at each site. Explain why this would make their results more reliable.[2]
3. (b)(ii)To measure the amount of vegetation cover the students used the piece of equipment shown in Fig. 7.2 (Insert). What is this piece of equipment called? Tick (✔) your answer below. Tick (✔) barometer callipers clinometer quadrat ruler[1]
4. (b)(iii)To measure humidity the students did a simple test which a student described in his fieldwork notebook, Fig. 7.3 (Insert). Suggest one weakness of this test.[1]
5. (b)(iv)The students also measured the time it took for water to infiltrate (soak into) the ground. Describe a fieldwork method to measure infiltration. Refer to equipment which could be used.[4]
6. (c)(i)Which site has the highest amount of vegetation cover? Circle your answer. site A site B site C[1]
7. (c)(ii)One set of measurement results is shown below. Percentage of vegetation cover = 68 Percentage of bare ground = 32 Humidity measurement = 90 seconds Infiltration time = 28 seconds At which site and for which measurement (1–5) were these results recorded? Site ................................................................................................................................................. Measurement number ......................................................................................................................[1]
8. (c)(iii)Use the results in Table 7.1 to calculate the average infiltration time at site B. Show your calculation below. Answer = .............................................. seconds[2]
9. (d)(i)Use the information in Table 7.1 to plot the following on Fig. 7.4: • the percentage of vegetation cover and the percentage of bare ground in measurement 3 at site C • how long the cobalt chloride paper took to turn pink (humidity measurement) in measurement 5 at site B • the infiltration time in measurement 5 at site C.[3]
10. (d)(ii)Before they made a conclusion to Hypothesis 1 the teacher reminded the students that the less time the paper took to turn pink the greater the humidity of the air. What conclusion would the students make about Hypothesis 1: Humidity is greater where there is more vegetation cover? Support your decision with evidence from Fig. 7.4 and Table 7.1.[4]
11. (d)(iii)The students decided that Hypothesis 2: Infiltration is quicker where there is more vegetation cover was correct. What evidence from Fig. 7.4 and Table 7.1 supports their conclusion?[3]
12. (e)Suggest why infiltration times are different at sites A and C. Look again at Fig. 7.1 (Insert) to help you to answer.[3]
13. (f)(i)One student wanted to show the number of different plant species seen at each site. Which one of the following would be suitable to show the information in Table 7.2? Tick (✔) your choice. Bar graph Flow diagram Kite diagram Radial graph Triangular graph Tick (✔)[1]
14. (f)(ii)Suggest two reasons why the number and types of plant species vary between the sites. Look again at Fig. 7.1 (Insert) to help you to answer.[2]

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