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1.15 The Impacts of Human Industry on Ecosystems. (Sec 5.4 p 126-130). Human activity affects ecosystems! . Agricultural activities affect ecosystems in a number of ways:
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1.15 The Impacts of Human Industry on Ecosystems (Sec 5.4 p 126-130)
Agricultural activities affect ecosystems in a number of ways: • Changing the land from a natural ecosystem (e.g. grassland, forest) to an artificial one (e.g. pasture, fields); this vastly reduces biodiversity
Agricultural activities affect ecosystems in a number of ways: • Addition of fertilizers can accumulate in the rivers and lakes, and poison food.
Agricultural activities affect ecosystems in a number of ways: • Soil degredation occurs when fertile topsoil is lost due to erosion and/or when soil nutrients are depleted; can occur when fields are left to fallow.
Scientists are trying to come up with ways to farm more ‘ecologically’, but maintain yields.
Forestry practices (harvesting timber from forests) has big ecosystem effects too: • Clear cutting completely destroy habitat (animals, plants, bacteria, soil affected)
Firewood adds to CO2 to atmosphere (~ half of world harvest of wood burned for fuel!)
Deforestation occurs when trees are cut and not replaced (replanted); can occur due to urban development (housing) or agriculture; habitat is totally gone
Fisheries affect ecosystems: • Overharvesting fish can cause the ecosystem to become unstable and collapse.
By-catch occurs when industrial fishing operations catch non-target species, leading to ‘waste kill’ (the animals are killed for no good reason).
Fish farming practices can lead to increased disease rates and pollution, and can have detrimental impacts on wild populations of fish and other organisms.
Traditional ecological knowledge and wisdom (TEKW) is possessed by people of indigenous cultures around the world, who have a unique understanding of their environment, and know how to live sustainably. • There is a growing body of interest in adopting TEKW practices in agriculture and resource management. • In many ways, people have already taken advantage of TEKW (e.g. many western medicines derived from plants used by indigenous peoples for thousands of years).