Chapter 59 & 60- Ecological Impact of Humans & Conservation Ecology

Recognize and understand the global challenges facing conservation efforts You’ve learned throughout the semester why diversity is essential; be able to describe the three levels of diversity in biodiversity. Why is loss of biodiversity so impactful?

Conservation is crucial for maintaining biodiversity and ecosystem health, but there are several challenges:

1. Climate Change: Warming temperatures, shifting weather patterns, and rising sea levels threaten habitats and species.

2. Habitat Loss: Urbanization, agriculture, and logging destroy critical habitats.

3. Invasive Species: Species introduced to new areas outcompete native species, disrupting ecosystems.

4. Pollution: Chemicals, plastics, and waste pollute air, water, and land, affecting species' health.

5. Overexploitation: Overfishing, hunting, and deforestation deplete resources faster than they can replenish.

Biodiversity can be viewed in three levels, each contributing to ecosystem stability and resilience:

1. Genetic Diversity:
   
   

   • The variety of genes within a species.
     Essential for adaptation and survival in changing environments.

   • Example: Genetic variation in crops allows for disease resistance.
     
     

2. Species Diversity:
   
   

   • The number of different species in a particular area.
     High species diversity leads to more stable ecosystems and better resilience to disturbances.

   • Example: Forests with a wide range of tree species support diverse animal populations.
     
     

3. Ecosystem Diversity:
   
   

   • The variety of ecosystems (forests, wetlands, grasslands, etc.) in a region or across the globe.

   • Different ecosystems provide unique services and support different species.

   • Example: Wetlands provide water filtration, while forests provide oxygen and habitats.

Why Is the Loss of Biodiversity So Impactful?

• Ecosystem services: Biodiversity supports essential functions like pollination, water purification, climate regulation, and soil fertility.

• Resilience: A diverse ecosystem can recover from disturbances (e.g., natural disasters, disease).

• Economic impact: Loss of biodiversity affects industries like agriculture, fishing, and tourism.

• Cultural value: Many cultures rely on biodiversity for food, medicine, and spiritual practices.

Know what the Endangered Species Act aimed to do 

The Endangered Species Act (1973) aims to protect and recover species at risk of extinction.

• Purpose:
  
  

  • Protects species from harmful activities like hunting or habitat destruction.

  • Helps restore habitats to support species recovery.
    Ensures that listed species receive necessary protections (e.g., funding, conservation actions).

• Key functions:

  • Listing species as endangered or threatened.

  • Designating critical habitats for those species.

  • Recovery plans for species populations.

Explain the major threats to biodiversity and recognize the human influence involved (acronym H.I.P.P.O. – habitat loss, invasives, pollution, population, overexploitation, )

H.I.P.P.O. is a useful acronym for remembering the main threats to biodiversity:

1. H - Habitat Loss: Destruction of natural habitats due to agriculture, urbanization, logging, etc.
   
   

2. I - Invasive Species: Non-native species that disrupt local ecosystems by outcompeting or preying on native species.
   
   

3. P - Pollution: Contamination of the air, water, and land with harmful chemicals, plastics, and waste.
   
   

4. P - Population (Human population growth): Increased human populations lead to greater demand for resources, putting pressure on ecosystems.
   
   

5. O - Overexploitation: Overharvesting of resources (e.g., overfishing, hunting, deforestation) faster than they can replenish.

Define biological magnification and how it impacts a food chain.

Biological Magnification

Definition: The process by which harmful chemicals (e.g., pesticides, heavy metals) become more concentrated as they move up the food chain.

Impact: These chemicals can harm organisms, disrupt reproduction, and cause health issues.

Be able to explain what climate change is and means. Recognize the basic chemistry of how converting harmless reservoirs of chemicals into gaseous atmospheric versions alters global temperatures and sea levels. 

Climate Change: Refers to long-term changes in temperature, precipitation patterns, and other aspects of Earth's climate.

Greenhouse Effect:

• Sunlight enters Earth's atmosphere, and some of it is reflected back into space.

• The Earth absorbs the sunlight and warms up, but this heat is trapped by greenhouse gases in the atmosphere.

Describe the human contribution to production of greenhouse gases and nutrient runoff into aquatic environments.

1. Greenhouse Gas Emissions:
   
   

   • Burning fossil fuels (coal, oil, natural gas) for energy is the largest source of CO2 emissions.

   • Deforestation reduces the planet’s ability to absorb CO2.

   • Agriculture (especially livestock farming) contributes methane (CH4).
     
     

2. Nutrient Runoff into Aquatic Environments:
   
   

   • Fertilizers used in agriculture wash into rivers and oceans, causing eutrophication.
     Excess nutrients lead to algal blooms that deplete oxygen in water, harming aquatic life.