How people affect biodiversity

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. Read this first

   One woodland over ten years (model data)

   cause	evidence
   land cleared for houses	30 hectares before, 12 hectares after
   a vine from another continent	covers 5 hectares of the ground
   a water test for a pesticide	none found

2. 1.

   Ari reads the woodland table. Which drivers of biodiversity loss have evidence here?

   • Habitat loss and pollution, since the three rows each name a driver
   • An invasive species alone, since the vine is the one living cause
   • Habitat loss alone, since 18 hectares is the largest change
   • Habitat loss and an invasive species have evidence; pollution does not

3. Direct drivers of change in nature, ranked by global impact so far (real data, IPBES 2019)

   rank	driver
   1	changes in land and sea use
   2	direct exploitation of organisms
   3	climate change
   4	pollution
   5	invasive alien species

4. 2.

   Bo reads the ranking. Which statement does the table support?

   • The top driver explains the loss, so drivers 2 to 5 can be set aside
   • Land and sea use changes have had the largest global impact so far; climate change ranks third
   • Climate change has had the largest global impact so far, since its warming reaches the whole planet
   • Invasive alien species rank first, since they spread the fastest

5. Two NOAA lists at the end of 2023 (real data, NOAA Fisheries, 2023)

   list	what puts a stock on it	stocks
   overfishing list	the catch rate is too high	21
   overfished list	the population is too small	47

6. 3.

   Esme reads the NOAA table. Which sentence matches it?

   • A stock can be too small, overfished, or caught too fast, subject to overfishing
   • The two lists name the same 21 stocks, counted twice
   • An overfished stock is gone, so 47 stocks have disappeared
   • Overfishing means the stock is too small, and overfished means the catch is too high

7. Wetlands since 1700 (real data, IPBES 2019)

   measure	value
   wetlands present in 1700 that were lost by 2000	more than 85%

8. 4.

   Jun reads the card. About how much of the 1700 wetland area was left in 2000?

   • Zero percent of it, since the wetlands were lost
   • Less than 15% of it
   • About half of it
   • More than 85% of it

9. DDT after the 1972 cancellation (real facts, US EPA)

   when	what the EPA states
   1972	the EPA issued a cancellation order for DDT because of its effects on wildlife
   after US use stopped	levels in the environment and in animals have gone down
   still today	residues from past use remain, because DDT lasts a long time in the environment

10. 5.

    Kira reads the card about DDT. What does it say happened after DDT use stopped in the United States?

    • Levels went up, because DDT lasts a long time
    • Levels went down, but residues from past use remain
    • Residues were gone, because the soil and water looked clean
    • Levels fell to 0 as soon as the order was issued

11. Tests at four sites on a model stream (model data)

    site	water looks	pesticide level (parts per billion)	limit (parts per billion)
    site 1	clear	2	5
    site 2	cloudy	0	5
    site 3	clear	9	5
    site 4	cloudy	4	5

12. 6.

    Luz reads the table. Which sites go over the pesticide limit?

    • Only site 3: 9 is above the limit of 5, though the water looks clear
    • Site 4: 4 is the highest reading among the cloudy sites
    • Sites 1 and 3: clear water hides pollution, so both are over
    • Sites 2 and 4: cloudy water shows the pollution
13. 7.

    Milo reads the graph. By year 4, what share of patch B's original species was lost?

    • 34%: the 34 species left
    • 68%: the 34 species that were left
    • 16%: the 16 species lost
    • 32%: 16 of 50 species
14. 8.

    Noah reads the graph. About how far uphill did the highest plant move each decade, and what fits the pattern?

    • About 40 m a decade, fitting a range that shifts upslope as the air warms
    • About 4 m a decade, the rise each year
    • About 160 m a decade, the whole rise counted as if it happened in one decade
    • No shift, since the plant stayed near 800 m
15. 9.

    Pia reads the graph. What does it show about the pesticide level after the ban?

    • It halved every 2 years and was still above 0 at year 8
    • It fell by 4 every 2 years and reached 0 by year 8
    • It reached 0 as soon as the ban began
    • It fell by the same amount each year

16. The zebra mussel (real data, USGS Nonindigenous Aquatic Species)

    fact	entry
    native range	Black, Caspian and Azov Seas
    likely route to the Great Lakes	a cargo ship's ballast water
    found today in	all of the Great Lakes

17. 10.

    Ren reads the zebra mussel card. Which statement is supported?

    • It is native to the Black, Caspian and Azov Seas and is invasive in the Great Lakes
    • It is native to ships' ballast water, which carried it to the lakes
    • It is native to the Great Lakes, since it is found in each of them today
    • It is invasive in the Black Sea, since it arrived there from the Great Lakes by ship