Do Now (Page 8)Global Guide: Samantha Hill

Country: New Zealand

Answer the Question:List 3 causes of Water Pollution.

Water Pollution in New Zealand

Samantha HillColumbia University

Sustainability Around the World

Where in the world is New Zealand?

True or False?

New Zealand is part of Australia

FALSE

True or False?

New Zealand has three ‘official’ languages

TRUE

True or False?

90 % of New Zealanders live within 25 miles of the coast

TRUE

True or False?

New Zealanders are often called “Kiwis”after the fruit

FALSE

Auckland

Wellington

Christchurch

New Plymouth

30 million sheep

6.6 million dairy cattle

6.6 million dairy cattle

GOOD NEWS for the dairy industry….

Particles Microbes Nutrients

NH3

PO4

NO3

Particles Microbes Nutrients

NH3

PO4

NO3

Particles

• Murky water—sunlight can’t get through

• Muddy layer on the stony riverbed

Particles Microbes Nutrients

NH3

PO4

NO3

• Cause disease in animals

• Cause disease in people—E. coli, Campylobacter….

Particles Microbes Nutrients

NH3

PO4

NO3

Particles

• Chemicals that promote growth…

• Cause algae to grow much faster

• Algae deoxygenate the water

• Some algae are toxic

More algae = less oxygen

O2

Assimilative Capacity

Assimilative CapacityThe ability of a water body to process a substance without

becoming degraded.

• Keep pollution levels below assimilative capacity

Assign every group member to a task. Two people doing the same task is ok.

Try to be specific—how does the water in the cup compare to the water in the bottle?Color? Clarity? How fast does it flow?

What did you do for this cup?

How do we reduce water pollution?

Riparian Planting

Riparian PlantingPlanting along the margins of a waterway (“riparian margins”)

to reduce erosion and pollution.

• Farming is a major source of water pollution

• Particles, microbes and nutrients

• Excess nutrients cause algal growth and deoxygenation

• Riparian planting

• Stock exclusion (fences)

• Pollution needs to be kept below the assimilative capacity of the waterway

• These practices are now mandatory for dairy farmers under the Sustainable Dairying: Water Accord (2012)

Any questions?

Kia ora!

Closing

Answer the two questions on Page 9