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?

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

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?

   • Wildlife corridor: its weighted total is 19
   • Protected area: 21 points, 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

5. 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

6. 3.

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

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

7. The wildlife corridor and three limits (model data)

   measure	corridor	limit (at most)
   cost (million dollars)	7	8
   land (hectares)	45	50
   time to start (years)	6	4

8. 4.

   Kira checks the wildlife corridor against each limit in the table. Which limit does it break?

   • No limit: its cost of 7 million is under the budget of 8 million
   • Budget: 7 million dollars is too near the 8 million limit
   • Land: 45 hectares is very close to the 50-hectare limit
   • Time: 6 years is more than the 4-year limit on time

9. 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

10. 5.

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

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

11. 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

12. 6.

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

    • 2 more beetles
    • 10 more beetles: 40 − 30
    • 8 more beetles
    • 40 more beetles
13. 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
    • Cover with removal was 50% more than without, since 66 − 16 = 50
    • In year 5, native cover was 66% with removal and 16% without, a gap of 50 points
    • Removal fixed the problem, so the plot needs no protection from any other driver

14. 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.

15. 8.

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

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

16. 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.

17. 9.

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

    • The plan with the highest single score wins, whatever the weights
    • 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
    • The scores stay the same, and the weighted totals can change

18. 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

19. 10.

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

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