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QUESTION 7 When predicting successional change which of the following would typically indicate that an ecosystem is progressing toward its climax community? Abundance of K-selected species | Biomass
QUESTION 28 (4 marks) Identify two differences between primary and secondary ecological succession. Refer to one example of each type of succession in your response.
QUESTION 2 The process of change in the species structure of an ecological community over time is known as (A) cyclic succession. (B) primary succession. (C) ecological succession. (D) secondary succession.
QUESTION 11 In which environment would primary succession occur? (A) fresh lava field (B) harvested wheat crop (C) grassland cleared by fire (D) forest damaged by a cyclone
QUESTION 23 (5 marks) To determine the species diversity and species richness of a wetland ecosystem ecologists surveyed communities adjacent to a river using two methods for each community: 1. random species sampling with predetermined grid numbers with 10 quadrats of 4 m? each used for these grids 2. three belt transect lines (50 m X 2 m) across predetermined sampling locations based on strata variation. The map shows the locations of quadrats and transect lines. The table shows survey results. Key m River % Salt marsh Mangroves . Paperbark swamp ‘ Belt transect line [[] Quadrat Not to scale Survey method Belt transect Species richness (number of species) a) Identify three differences between the survey methods used to determine species diversity and species richness in the ecosystem. [3 marks] b) Draw a conclusion about the most suitable method for estimating species diversity and species richness of the communities in this wetland ecosystem. Give a reason to support your conclusion. [2 marks]
QUESTION 3 (3 marks) In coastal areas and deserts bare sand dunes may be colonised by plants such as members of the Poaceae family (grasses). Identify three features of these plants that make them effective colonisers.
QUESTION 13 (3 marks) The data shows changes in relative abundance of ground cover biomass and species diversity for an abandoned sand mine site over time. Key D Bare ground QGrasses (e.g. spinifex tussock grass) . Seedlings/shrubs (e.g. banksia eucalypt) Leaf litter I:] Mature trees Abundance Key D Biomass — Species diversity Biomass (kg/mz) Time Based on the information provided predict whether further ecological succession would occur in this community. Justify your answer with two relevant reasons.
QUESTION 19 The graph shows the effect of light intensity on the germination success of seeds from four plant species. 100 . .......... Species I 80 g = 60 = < N — - Species II 40 O SN Species 111 201 T e . eec® eec® ...... . ) e . e Species IV Light intensity Which is most likely to be a pioneer species? (A) 1 (B) 1I (C) I (D) 1V
QUESTION 3 (4 marks) A glacier has retreated leaving a large amount of gravel small rocks sand and mud. a) Explain the steps of succession that would occur if the glacier continues to retreat. [3 marks] b) Identify the type of ecological succession. [1 mark]
QUESTION 6 (5 marks) An environmental report identified overexploitation habitat destruction and pollution as human activities affecting biodiversity in Australia. The tables show the estimated impact of each activity in 2011 and 2016. 2011 2016 Assessment grade Confidence Assessment grade Very Very H ac‘ggfiis high | High | Low | low high | High | Low impact 1mpact 1 pact 1 pact grade trend impact 1mpact 1 pact 1 pact grade trend Improving Very low impact: Few if any . Adequate: Adequate high- species and/or ecosystems are quality evidence and high level Getting worse suffering substantial adverse effects of consensus from this pressure E Biable Low impact: A small proportion Somewhat adequate: Adequate of species and/or ecosystems are high-quality evidence or high suffering substantial adverse effects level of consensus from this pressure High impact: A significant Limited: Limited evidence or proportion of species and/or limited consensus ecosystems are suffering substantial adverse effects from this pressure Very high impact: A large G Very limited: Limited evidence proportion of species and/or and limited consensus ecosystems are suffering substantial adverse effects from this pressure a) Explain how one human activity identified in the tables could reduce biodiversity. [1 mark] b) Predict which human activities will have the highest and lowest impact on biodiversity in 2023. Explain your reasoning using evidence from the tables. [4 marks] Highest impact: Lowest impact:
QUESTION 4 This figure shows the relationship between spatial and temporal scale of drivers of ecosystem change. The size of the circles represents the proportion of drivers at a certain spatial scale that had a certain speed. very slow slow medium Temporal scale fast local national global Spatial scale Agricultural intensification along a river has led to substantial increases in fertiliser application and increases in stock numbers. From the given data predict the speed of ecosystem change along this river. (A) fast (B) medium (C) slow (D) very slow
QUESTION 8 Which feature makes pioneer species effective colonisers? (A) large seeds (B) slow-growth rate (C) shade-tolerant seedlings (D) ability to fixate nitrogen
QUESTION 25 The table below shows the probability of the replacement of one individual tree by another of the same or different species in 50 years’ time. Occupant in 50 years Present occupant Grey birch Red maple Blackgum Beech Red maple 0.00 0.53 0.14 0.31 Blackgum 0.01 0.25 0.57 0.17 Which species is most likely to replace grey birch in a 50-year temporal successional change in this forest? (A) grey birch (B) red maple (C) Dblackgum (D) beech
QUESTION 29 (6 marks) The diagram below shows fossilised marine organisms found in a site across seven stratum layers. 27 1l (S ’@ ek N b e %\}? 7 a) Analyse the data above to identify three relationships that provide evidence of changes in past ecosystems. Identify at least one biotic change and at least one abiotic change. b) From the given information determine the species richness (D) for strata 2. Use the following formula: S =T Where s= the number of different species represented in the sample and N = the total number of individual organisms in the sample c) Identify one limitation of using fossil evidence to determine species richness.
QUESTION 30 (6 marks) The figures below show a forest before harvesting (pre-harvest) and after harvesting (post-harvest). Pre-harvest ' Post-harvest Identify an ecological surveying technique and sampling method that could be used to effectively analyse the change in species diversity between the two ecosystems. Identify a strength and a limitation of each of your choices.
QUESTION 10 The graph shows extinction rates over time. a ee NO) PPD PS 107 Extinction rate (families per million years a a re 500 450 400 350 300 250 200 ©1506 6100 8§©650 0 Millions of years ago (Mya) How many times in the past 500 million years has the extinction rate exceeded 14 families per million years? (A) 3 (B) 4 (C) 5 (D) 6
QUESTION 7 (5 marks) The diagram shows the stages of succession in an ecosystem. Stage 1 Stage 2 Stage 3 Bare rock Lichen and Trees and shrubs herbaceous plants Time Stage 4 Mature forest a) Identify the type of ecological succession depicted. Explain your reasoning. b) Infer two features of the species in stage 2 and describe the role of these species in ecological succession. [2 marks] [3 marks]
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