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QUESTION 16 Identify the graph that represents the highest species richness with the greatest species evenness. (A) ©) Proportional abundance (log) Proportional abundance (log) 1000 300 100 30 10 3 1000 300 100 30 10 20 30 40 50 Rank I [ [ [ ] 10 20 30 40 50 Rank (B) (D) 1000 = 300 R 5\@/ 100 E2 30 Q = ST 10 A 2 2 3 0 10 20 30 40 50 Rank 1000 = ;5 300 §§ 100 5 £ 30 &9 Q;:E 10 < 3 1
QUESTION 4 (8 marks) Fish species diversity and coral cover were surveyed at a coral reef before and after a cyclone. The results of the fish transect data were collected and their trophic groups are shown. Before cyclone After cyclone Species Species . Species | Famity |0 [ d [coea i [ o [ p [Total erios 1 [ ] [ [ 2 omeioniod | 2 | | | |2 i | | [1[317] 28 pomeans| | | | | [8]7] 15 Key h = herbivore d = detrivore co = corallivore ca = carnivore i = benthic invertivore 0 = omnivore p = planktivore Rugosity transect data before cyclone Rugosity transect data after cyclone 2.5 2.5 3.0 3.0 35 - 35 g £ = 4.0 = 4.0 245 245 5.0 5.0 5.5 5.5 6.0 6.0 0 50 100 150 200 250 0 50 100 150 200 250 Transect seconds (10 s = 1 m approx.) Transect seconds (10 s = 1 m approx.) a) Determine the family most affected by the cyclone. Explain your reasoning. [2 marks] b) Draw conclusions about how changes in habitat complexity influenced the diversity of fish species found at the reef. [6 marks]
QUESTION 8 Identify the species seen on the greatest number of reefs in location III. (A) Po (B) Ac (C) St (D) Mn
QUESTION 12 When the recovery pathway of an ecosystem differs from its degradation pathway the ecosystem (A) shows hysteresis. (B) has low resilience. (C) has high biodiversity. (D) exists in a single stable state.
QUESTION 22 (5 marks) a) Identify an argument for mangrove conservation. Give two reasons to support your argument. [3 marks] b) Identify a management strategy that could support the health of mangrove habitats. Explain your reasoning. [2 marks]
QUESTION 2 Recent surveys in the Gulf of Carpentaria have shown large-scale mangrove loss. Determine the expected responses from reef fish species that use this habitat during their life cycle. Larval recruitment Juvenile populations Adult populations (mangroves) (mangroves) (reef) (A) Immediately decline Immediately decline Initially unaffected then decline over time (B) Initially unaffected then Initially unaffected then Initially unaffected then decline over time decline over time decline over time ©) Initially unaffected then Initially unaffected then Immediately decline decline over time decline over time Immediately decline Immediately decline Immediately decline
QUESTION 20 When designing marine protected areas what best describes the connectivity criterion? (A) (B) (C) (D) Distances between habitats are sufficient to enable organism transfer between them. Different habitat types are included to ensure habitat maintenance. Reserves are large enough to minimise edge effects. Multiple different habitat types are included.
QUESTION 24 (3 marks) Under La Nijia conditions there is a greater temperature contrast between the eastern and western tropical Pacific Ocean than under normal conditions. a) Identify one effect this scenario has for weather conditions on Australia’s east coast. [1 mark] b) Describe an impact on a local marine environment associated with the effect from Question 24a). [2 marks]
QUESTION 3 (11 marks) a) Identify the system that enables ocean water to resist pH change when exposed to increased atmospheric carbon dioxide (CO ). [1 mark] b) Identify one natural and two anthropogenic causes of increased atmospheric CO . [3 marks] Natural: Anthropogenic: c) Describe how increased atmospheric CO affects levels of hydrogen and carbonate ions in ocean waters. [4 marks] d) Explain what implications a change in levels of carbonate ions from increased atmospheric CO has for shell-forming organisms. [3 marks]
QUESTION 21 The graph below shows the results of a reef survey. Simpson Diversity Index (functional groups) 1.7 1.9 2.1 2.3 Rugosity The graph suggests that habitat rugosity between 1.22 and 2 supports (A) lower levels of functional group diversity. (B) greater levels of functional group diversity. (C) optimal levels of functional group diversity. (D) stabilised levels of functional group diversity.
QUESTION 29 (2 marks) The graph below shows Acropora species rank abundance data. Relative abundance 0 10 20 30 40 Rank abundance Analyse the given information to identify the relationships shown in terms of species richness and evenness.
QUESTION 31 (2 marks) The figure below outlines factors influencing a marine ecosystem. KELP FOREST URCHIN BARREN : Tipping point | —- Sea otter decline Sea otter hunted to used as an early near extinction warning indicator that Precautionary buffer écosystem may shift = Ly @ ) ] 6.\7 Set target sea otter densities below 9 Set target sea'otter densities an estimated threshold to stay X above an estimated threshold to outside of the precautionary = maintain kelp forest ecosystem buffer and maintain urchin barrens o n o ‘» © & O = Identify from the given information two features of ecological tipping points that could be applied to coral reefs. . 2.
QUESTION 28 (3 marks) Assess the data below which was collected using a line intercept transect. e |0 Porites sp. Poczllopm sp. iy |0 ey |5 a) Determine the diversity of the reef system studied using Simpson’s Diversity Index. Yn(n-— 1)) N(N-1) Show your working. SDI = 1 — ( [2 marks] b) Draw a conclusion about the diversity of this reef ecosystem. [1 mark]
QUESTION 6 (4 marks) A fish survey of four reef habitat areas and three mangrove habitat areas was conducted. The aim was to determine the mangrove habitat with the highest level of connectivity for juvenile and adult reef fish. The mangrove habitats were ranked on their nursery function. Reef habitat area number i [w [ Number of juvenile fish in Overall connectivity Mangrove habitat area location to coral reefs Overall connectivity to mangrove habitat Using the information above identify which mangrove habitat would be the most crucial in this situation. Give reasons to support your response.
QUESTION 7 (2 marks) A mass coral bleaching event in 1998 caused a decline in average coral cover for a reef. Identify an implication for the fish populations associated with this reef. Give a reason for your response.
QUESTION 10 (3 marks) Describe three ways in which coral reefs benefit from herbivorous fish. 1. 2. 3.
QUESTION 12 (3 marks) A study of three isolated offshore reef marine protected areas in subtropical East Australia was conducted. The study provided mitochondrial and microsatellite data in an endemic species of anemone fish Amphiprion mccullochi. This data was used to infer gene flow and levels of population replenishment. The research found that over evolutionary time this species had high levels of gene flow and genetic diversity. However the current anemone fish population had limited gene flow and species replenishment. Explain the connectivity between the offshore reef ecosystems and the role this plays in the anemone fish’s replenishment.
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