Ecosystems & Sustainability Handout PDF

# **CONNECTIONS** ## **HANDOUT ch.2 - ecosystems & sustainability** ## **Ecosystems and human activities** Here is a list of some various human activities that negatively affect ecosystems: 1. **Agriculture:** more than 40% of the Earth's surface now supports agriculture, where forests once exis...

# **CONNECTIONS** ## **HANDOUT ch.2 - ecosystems & sustainability** ## **Ecosystems and human activities** Here is a list of some various human activities that negatively affect ecosystems: 1. **Agriculture:** more than 40% of the Earth's surface now supports agriculture, where forests once existed. Fertilizers used for crops are destroying soils, land and water systems. 2. **Deforestation:** Deforestation destroys wildlife, contributes to climate change (less trees to absorb CO2 gas). Almost half of all the trees on the planet are now gone since the industrial revolution began. Many indigenous peoples are displaced as a result. 3. **Overpopulation and overconsumption:** Humans need a lot of space which results in more clear-cutting (less trees). We also consume a large amount of resources for our own needs, including non-renewable resources. 4. **Plastic production and chemicals:** Waste plastic and chemicals are everywhere on Earth, even in the oceans. Chemicals and chemicals from plastics are released which can disrupt cell biology in various organisms. 5. **Emission of carbon dioxide and other greenhouse gases:** Responsible for the Earth warming up and climate change (including extreme weather events like heatwaves, flooding, hurricanes, droughts, etc.) Ocean and land ecosystems are altered, impacting food chains and webs. 6. **Destruction of the reefs:** Contributors are water pollution, climate change, overfishing and acidification of the oceans cause coral reef destruction. They are critical areas for fish growth and reproduction. 7. **Draining and destruction of critical freshwater Aquifers:** Intensive agriculture over-drains rivers and important underground natural aquifer water systems. As a result, diverse animal and plant life has shrunk by more than half as an effect. 8. **Overhunting and overexploitation:** Natural resources are put under pressure through activities such as overfishing and mining, which ultimately affects ecosystems by disrupting food chains. 9. **Invasive species:** Bringing species that don't originally belong (either on purpose or by mistake) can be devastating on food chains and webs as they often don't have any natural predators and compete with other native species. # **SUSTAINABLE PRACTICES** ## **Ecosystems are very sensitive to change.** When an ecosystem is well balanced and is existing in this perfect balance, it can last a very long time and the ecosystem is said to be in **dynamic equilibrium**, and is sustainable in the long run over time. There are some things (practices) that we can do to help ecosystems attain sustainability: ## **1. Practices in agriculture** - **Reduce our reliance on pesticides:** instead focus on natural processes. - Insects can be introduced that are predators for insect pests that attack crops. - Planting more than one crop in one area may reduce pests. - Mechanical removal of weeds. - **Crop rotation:** increases foil fertility, as healthy soil promotes healthy crops and livestock. - **Hydroponics and aquaponics:** growing plants without soil. In aquaponics, aquatic animals (for example, fish) are put into the water supplying the hydroponic crops. The waste from the fish helps nourish the plants. - **Urban agriculture:** grow food close to home, including in cities themselves. - **Agroforestry:** growth of trees and shrubs among grazing land or crops. Trees and shrubs stabilize the growing conditions, protecting against drought, increasing soil stability, and minimize nutrient runoff. - **Permaculture:** use crops in the same farm that interact with each other just like plants in an ecosystem would function. Multiple crop species in one area. - **Cover crops:** Not leaving soil barren, preventing soil erosion, suppress weed growth and enhances soil quality. - **Soil enrichment and natural fertilization:** leave crop residue in the field after harvest, use composted plant material or animal manure. - **Better water management:** grow crops that are more adaptable to local weather conditions. Well planned irrigation systems and rainwater harvesting. ## **2. Practices in various communities:** **Traditional knowledge and values and aboriginal sustainability concepts:** 1. **Mother Earth is depicted as a living person:** If abused, she will no longer provide a life-giving force for future generations (a major focus). 2. **Laws of nature:** all life-sustaining activities have a time and season. For example, animals were not hunted during their reproductive cycles. 3. **Interrelationships and interconnectedness:** never take things for granted. Everything (animal, plant, person, rocks, etc.) has its place in the world and has its own role and function. Therefore everything that exists must be treated with respect and everything that we do affects the environment in some way.