Compare ways to protect biodiversity and choose the best

Grade 9 Science Worksheet

Circle the best answer.

1. Read this first

   Use this

   Decision matrix (model data), scores 1 to 5, a higher score is better in every column. Weights: benefit to species counts 3 times, low cost counts 2 times, few side effects counts 1 time. Protected area, benefit to species 5, low cost 2, few side effects 4; Wildlife corridor, benefit to species 4, low cost 3, few side effects 4; Seed bank, benefit to species 2, low cost 5, few side effects 5.

2. 1.

   Pia weights the goals as shown. What is the weighted total for the protected area?

   • 11 points
   • 23 points: 15 + 4 + 4
   • 5 points
   • 21 points

3. Use this

   Decision matrix (model data), scores 1 to 5, a higher score is better in every column. Weights: benefit to species counts 3 times, low cost counts 1 time, few side effects counts 1 time. Invasive-species control, benefit to species 3, low cost 4, few side effects 3; Wildlife corridor, benefit to species 4, low cost 3, few side effects 4; Reducing runoff, benefit to species 4, low cost 3, few side effects 5; Protected area, benefit to species 5, low cost 2, few side effects 4.

4. 2.

   Ren gives benefit a weight of 3 and the other two columns a weight of 1. Which plan has the highest weighted total?

   • Reducing runoff: its plain sum, 12, is the highest of the rows
   • Invasive-species control: it has the top low-cost score, 4, so it is good value
   • Protected area: 21 points, the highest weighted total
   • Wildlife corridor: its weighted total is 19

5. Use this

   Decision matrix (model data), scores 1 to 5, a higher score is better in every column. Weights: benefit to species counts 3 times, low cost counts 2 times, few side effects counts 1 time. Protected area, benefit to species 5, low cost 2, few side effects 4; Wildlife corridor, benefit to species 4, low cost 3, few side effects 4; Seed bank, benefit to species 2, low cost 5, few side effects 5.

6. 3.

   Esme uses the weights shown. By how many points does the protected area beat the wildlife corridor?

   • 3 points
   • 1 point: 23 − 22
   • 0 points
   • 2 points

7. Five plans and three limits (model data)

   plan	benefit score	cost (million dollars)	land (hectares)	time to start (years)
   Protected area	5	9	120	5
   Wildlife corridor	4	6	40	3
   Invasive-species control	3	2	15	1
   Seed bank	2	3	1	2
   Reducing runoff	3	4	25	2
   limit (at most)	no limit	8	50	4

8. 4.

   Jun keeps only plans that meet all three limits. Among those, which has the highest benefit score?

   • Reducing runoff: it meets all three limits and has benefit 3
   • Invasive-species control: it has the lowest cost, 2 million dollars
   • Protected area: it has the highest benefit score overall, 5
   • Wildlife corridor: benefit 4, and it stays within all three limits
9. 5.

   Milo reads the table and the three limits. How many of the five plans meet all three limits?

   • 5 plans
   • 3 plans
   • 4 plans
   • 2 plans

10. Beetles in patch B, a second model (model data)

    generation	beetles without a corridor	beetles with a corridor
    0	40	40
    1	38	40
    2	36	40
    3	34	40
    4	32	40
    5	30	40

11. 6.

    Tala runs a simulation of a beetle species in patch B. By generation 5, how many more beetles were there with a corridor?

    • 8 more beetles
    • 2 more beetles
    • 40 more beetles
    • 10 more beetles: 40 − 30
12. 7.

    Zee reads a model graph that tests removing an invasive plant. Which statement matches the graph?

    • Native cover in the plot without removal stayed level at 40% for the five years
    • Removal fixed the problem, so the plot needs no protection from any other driver
    • In year 5, native cover was 66% with removal and 16% without, a gap of 50 points
    • Cover with removal was 50% more than without, since 66 − 16 = 50

13. Use this

    Decision matrix (model data), scores 1 to 5, a higher score is better in every column. Weights: benefit to species counts 2 times, helps species shift range counts 3 times, low cost counts 1 time. Protected area, benefit to species 5, helps species shift range 2, low cost 2; Wildlife corridor, benefit to species 4, helps species shift range 5, low cost 3; Reducing runoff, benefit to species 3, helps species shift range 1, low cost 4; Seed bank, benefit to species 2, helps species shift range 1, low cost 5.

14. 8.

    Luz adds a new goal, helps species shift range, that counts 3 times. Which plan has the highest total now?

    • Protected area: it still has the highest benefit score, 5, so it wins
    • Wildlife corridor: 8 + 15 + 3 = 26 points, the highest total
    • Seed bank: it has the top low-cost score, 5, so it is good value
    • Wildlife corridor and protected area tie, with 26 points each

15. Use this

    Decision matrix (model data), scores 1 to 5, a higher score is better in every column. Weights: benefit to species counts 3 times, low cost counts 2 times, few side effects counts 1 time. Protected area, benefit to species 5, low cost 2, few side effects 4; Wildlife corridor, benefit to species 4, low cost 3, few side effects 4; Reducing runoff, benefit to species 3, low cost 4, few side effects 5; Seed bank, benefit to species 2, low cost 5, few side effects 2.

16. 9.

    Ari changes the weights in the matrix. Which statement is correct?

    • The plan with the highest single score wins, whatever the weights
    • The scores stay the same, and the weighted totals can change
    • A heavier weight on low cost makes the cheapest plan win
    • The scores in the table must change too, because a heavier weight raises a score

17. Four plans, weighted for a land limit of 50 hectares (model data)

    plan	benefit (×3)	low cost (×2)	few side effects (×1)	land (hectares)
    Protected area	5	2	4	120
    Wildlife corridor	4	4	3	40
    Reducing runoff	3	4	5	25
    Seed bank	1	5	5	1

18. 10.

    Noah weights the columns as shown and has a land limit of 50 hectares. Which plan should be chosen?

    • Wildlife corridor: 23 points, tied, and 40 hectares fits the limit
    • Reducing runoff: its plain sum, 12, is the highest in the table
    • Seed bank: it costs the least and needs just 1 hectare of land
    • Protected area: it ties at 23 points and has the top benefit score, 5