Environmental Ethics and Biodiversity
Chapter 6: Ecosystem Services
Definition: Ecosystem services are the various benefits that humanity derives from ecosystems.
Categories of Ecosystem Services:
Provisioning Services: Products obtained from ecosystems, including:
Food: Essential nutrition obtained from various sources.
Medicine: Therapeutic substances derived from biological organisms.
Consumable goods: Products that can be used up, such as timber and fiber.
Non-consumable goods: Resources that provide benefits without being consumed.
Regulating Services: Natural regulatory processes provided by ecosystems to maintain environmental balance, including:
Climate Regulation: Ecosystems help stabilize or moderate climate extremes.
Soil Fertility: Ecosystems contribute to the health and nutrient availability of soil.
Water: Ecosystems filter and purify water, maintaining its quality.
Pollination: Essential for biodiversity and agricultural productivity.
Erosion Control: Prevention of soil loss due to water or wind.
Supporting Services: Underpinning processes essential for the maintenance of ecosystems, including:
Nutrient Recycling: Reuse of nutrients within ecosystems.
Air and Water Purification: Natural processes that cleanse the environment.
Pest Control: Natural regulation of pest populations through predator-prey dynamics.
Cultural Services: Non-material benefits obtained from ecosystems, including:
Recreation: Activities in nature that promote health and well-being.
Spiritual/Religious: Cultural practices and beliefs connected to nature.
Health/Well-being: Ecosystems enhance human resilience and mental health.
Niche Partitioning
Definition: The process whereby similar species exploit the limited resources in an ecosystem by dividing them temporally or spatially to increase efficiency.
Example of Niche Partitioning: Several species may have different hunting times or foraging areas, minimizing direct competition.
Lyme Disease and Biodiversity
Dilution Effect: A biological mechanism where the replacement of competent hosts (which can carry and transmit Lyme disease) by less competent hosts reduces Lyme disease prevalence.
Chapter 8: Extinction
Definition of Extinction: The loss of a species that occurs when its last individual dies.
IUCN (International Union for Conservation of Nature): Organization recognizing the extinction status of species across the globe.
Conservation Status: The IUCN Red List identifies species facing extinction risks, using well-defined biological criteria for evaluation.
Levels of Extinction:
Locally Extinct: Species no longer found in areas where they were once common.
Globally Extinct: Species that no longer exist anywhere on Earth.
Ecologically Extinct: Species that exist but are so rare that their ecological role is essentially eliminated.
Amphibians at Risk: Amphibian species are at highest risk for extinction due to habitat loss, which impacts them doubly because many amphibians have two habitats (aquatic and terrestrial).
Causes of Risk:
Drought
Sensitivity to pesticides
Chytrid fungus infection
Increased predation from invasive species.
Environmental Change: Major Threats to Species
Major Forms of Environmental Change:
Invasive Species: Non-native species that disrupt the ecosystems into which they are introduced.
Habitat Loss: The complete destruction of habitats, leading to loss of biological communities and ecological functions.
Overexploitation: Unsustainable harvesting of species or resources at rates faster than they can replenish.
Climate Change: Long-term shifts in temperature and weather patterns affecting ecosystems and species.
Chapter 9: Habitat Loss
Definition of Habitat Loss: The complete elimination of a habitat, along with its biological communities and ecological functions.
Habitat Fragmentation: The subdivision of larger continuous habitats into smaller patches, often leading to increased biodiversity loss.
Degradation of Habitat: Human activities that make remaining habitats less conducive to life, such as pollution or unsustainable agriculture practices.
Drivers of Habitat Loss:
Urbanization
Agriculture (e.g., palm oil plantations)
Extractive industries (e.g., logging)
Chapter 10: Overexploitation
Definition of Overexploitation: The excessive harvesting of renewable resources, which leads to the depletion of those resources.
Types of Overexploitation:
Commercial Exploitation: Driven by economic incentives, leading to illegal wildlife trafficking.
Subsistence Exploitation: Unsustainable hunting practices for food.
Recreational Exploitation: Hunting for sport without consideration of ecological effects.
CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora): A treaty designed to protect endangered species by regulating international trade and promoting sustainable practices.
Bushmeats: Hunting wildlife for food, often leading to zoonotic diseases due to increased human-animal interactions and can sometimes help control wildlife populations.