Enviro-imprints – introduction
New Zealand has been inhabited by humans only relatively recently but, in the last 800 years, we have made a big impact on our environment, and have altered it biologically, chemically and physically.
Car exhaust
Car exhaust can contain particulates, especially if the vehicle is an older car or runs on diesel. Scientists are concerned that the particulates carry toxic chemicals, such as nitrous oxide and carbon monoxide, deep into our lungs where they can make us ill.
The US EPA reports that a typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year. CO2 is a greenhouse gas.
Our biological imprints – By introducing plants and animals, both intentionally as a food source and unintentionally as ‘stowaways’ on voyages from other lands, we have changed our environment. Many of these plants and animals have become pests and have reduced the biodiversity of our land.
Our chemical imprints – We have introduced chemicals into the environment to kill pests, fertilise our crops and as by-products of industry. Many of these chemicals are toxic to living organisms and have contaminated our soil, water and air.
Our physical imprints – By cutting down forests to increase pasture for crops, we have increased erosion and changed the appearance of the landscape. This alteration of the landscape has also had an effect on our local microclimates, with cities being warmer and plains having a higher wind flow.
Insecticide spraying
Insecticides are chemicals that are toxic to insects. They are commonly used in agriculture to reduce the number of pest insects that might damage the crop or pasture. Today, insecticides are usually specific to insects and should not harm other animals. But scientists are finding that they may, in fact, have long-term effects on other non-target animals (species that are not the intended victims) through toxicity or reduced food sources.
Living in New Zealand, we take for granted that the air we breathe is pure, the water we drink is not going to make us sick and the soil we farm in cannot harm us. While this vision is not entirely true, we are fortunate compared to many other countries. A lot of work and important research goes into keeping us well and into reducing our impact on the environment.
Air quality
The most common form of air pollution is from particulates – small particles released from burning material. Our scientists, Dr Simon Kingham and Dr Peyman Zawar-Rezaare, are researching the link between human health and the level of particulates. Learn more about this in the article Air quality.
Particulates
Professor Simon Kingham, from the University of Canterbury, discusses how air pollution can be made up of many components. The size and amount of particulates in the air can give a measure of the level of air pollution. A team of researchers collect samples of air in various ways to measure these particulates, which can vary in size.
Water quality
Poor quality drinking water can cause disease outbreaks. The article Water quality highlights the importance of the catchment area and how this water is treated. Scientists at ESR are researching how best to prevent disease-causing organisms entering our drinking water and treatment methods to maintain the high quality of water we receive from our taps.
Detecting viruses in drinking water
ESR scientist Dr Wendy Williamson is developing a method for detecting viruses in the water. She is also monitoring waterways so that a standard for safe drinking water can be developed. The Ministry of Health are interested in determining the numbers and types of viruses that are found in our drinking water.
Soil quality
Chemicals from farming and industrial practices, both past and present, and geological processes can contribute to the level of toxins in our soil. These toxic chemicals can leach into our waterways and have a detrimental effect on our fragile aquatic ecosystem. Detecting toxins in the soils can be a difficult and expensive process. Dr Ravi Gooneratne uses earthworms as an indicator of the presence of certain chemicals. The articles Soil quality, Soil contamination, Organochlorides and Bioindicators provide more details.
Earthworms
Earthworms help break down organic matter into soil and are an important indicator of the health of the soil. They can also be used directly as a ‘tool’ to determine if certain toxins are present, by measuring the timing of their response to a touch.
Take up the challenge
Student activities are a mix of hands-on experiments, web quests and debates. Explore air quality issues with Investigating air pollution and Sources and effects of air pollution. Learn about water quality with Water issues and Water pollutants on trial. Examine soil quality issues with Site clean-up and Biodegradability experiment.
The 2017 Connected article Sensing data describes how a team of researchers used technology and big data to help make Christchurch a healthier smarter city to live in
Question bank
The Enviro-imprints – question bank provides a list of questions about the impact we have on our enironment around us and places where their answers can be found. The questions support an inquiry approach.
Key terms
For explanations of key concepts, see Enviro-imprints – key terms.
Timeline
Use this timeline to discover some of the impacts we have made on our environment since humans first arrived in New Zealand.
