ENSC1A

• Biodiversity is the variety of life on Earth and the essential interdependence of all living things
• Levels of Biodiversity:

  • Genetic Diversity
  • Species Diversity
  • Ecosystem Diversity
• Genetic Diversity:

  • Amount and variety of genetic material within individuals, populations or communities
  • Different gene sets define an individual or a population's ability to tolerate stress from environmental factors
• Species Diversity:

  • Species richness: numerical count of species present in an area, tends to increase over area and sampling intensity
  • Species evenness: relative abundance of different species in an area
  • Importance of species diversity: each species has an important role in an environment
• Ecosystem Diversity:

  • Deals with variations in ecosystems within a geographical location and its impact on human existence and the environment
• Values of Biodiversity:

  • Consumptive Value
  • Productive Value
  • Social Value
  • Ethical Value
  • Aesthetic Value
  • Option Value
• Threats to Biodiversity:

  • Habitat destruction
  • Overexploitation
  • Pollution
  • Global climate change
  • Invasion by introduced species
  • Underlying social conditions
• Philippines' Biodiversity:

  • One of the places richest in biodiversity
  • Endemic native species
  • Critically Endangered, Endangered, Vulnerable, Other threatened species
• Organism/Community Interaction:

  • Symbiosis, Predation, Competition
• Symbiosis:

  • Living together
  • Three main categories: Mutualism, Commensalism, Parasitism
• Mutualism:

  • Both species benefit in the relationship
  • Relationship is often obligatory, both species depend on each other for survival
• Commensalism:

  • Relationship where one organism benefits while the other is not affected
• Parasitism:

  • Relationship where one organism (parasite) lives in or on another organism (host) and derives nourishment
  • Parasite is smaller than the host and harms but does not kill the host
• Two classifications of parasites:

  • Ectoparasites live on the surface of their host, such as fleas or lice
  • Endoparasites live inside the body of the host, for example, roundworms
• Mimicry is when one species imitates another to gain benefits enjoyed by that species

  • Examples include Harlequin Snake eel, Frogfish, Mimic octopus
• Competition:

  • Two or more organisms strive to obtain the same limited resources
  • Only one organism benefits but both are harmed to some extent
  • Types of competition: Competition, Contest competition, Scramble competition
• Predation:

  • One animal or organism, known as a predator, kills and eats another, known as the prey
  • Predation enhances fitness of predator but reduces fitness of prey
  • Herbivory is a form of predation
• Energy flow through ecosystems:

  • Ecosystems require continuous input of energy, mainly from sunlight
  • Trophic levels refer to each step in the flow of energy through an ecosystem
  • Only 10% of energy is transferred to the next trophic level
  • Biomass is the weight of living material in a trophic level
• Classification of living organisms:

  • Autotrophic organisms fix life energy, use simple inorganic substances, and build up complex substances
  • Heterotrophic organisms utilize, rearrange, and decompose complex materials
  • Producers, also called autotrophs, make nutrients they need from compounds and energy obtained from the environment
  • Consumers cannot produce nutrients they need through photosynthesis or other processes
  • Examples: Plants, Lichens, Phytoplankton, Algae
• Food Chain:

  • Linear sequence of organisms starting from producers and ending with decomposer species
• Pollution:

  • Any undesirable change in the physical, chemical, or biological characteristics of the environment
  • Pollution can occur naturally or unnaturally
  • Types of pollution sources: Point sources, Nonpoint sources
• Air Pollution:

  • Chemicals added to the atmosphere by natural events or human activities in harmful concentrations
  • Primary pollutants are emitted directly from identifiable sources
  • Secondary pollutants are produced in the atmosphere through chemical reactions among primary pollutants
  • Major classification of air pollutants: Carbon Monoxides, Carbon Dioxide, Nitrogen Oxide and Nitric Acid, Sulfur Oxides, Particulate Matter, Ozone
• Water Pollution:

  • Contamination of water bodies by human activities
  • Groundwater pollution occurs from release of pollutants into underground water reservoirs
  • Surface water pollution involves hazardous substances coming into contact with surface water
  • Nutrient pollution is the excessive addition of nutrients like nitrogen and phosphorus to bodies of water
• Bioaccumulation vs Biomagnification:

  • Bioaccumulation is the increase of a toxic substance in an organism
  • Biomagnification is the increase of a toxic substance along a food chain from lower to higher levels
• Solutions in Water Pollution:

  • Prevent groundwater contamination
  • Reduce non-point run-off
  • Reuse treated wastewater for drinking and irrigation
  • Find substitutes for toxic pollutants
  • Practice the three R’s of resource use (reduce, reuse, recycle)
  • Reduce air pollution
  • Reduce poverty
  • Slow population growth
• Soil Pollution:

  • Occurs when toxic chemicals or contaminants in soil are in high enough concentrations to pose risks to plants, wildlife, and humans
  • Major causes include industrial waste, deforestation, excessive use of fertilizers and pesticides, garbage pollution
• Major causes of soil pollution:

  • Industrial waste
  • Deforestation
  • Excessive use of fertilizers and pesticides
  • Garbage pollution
• Effects of soil pollution:

  • Climate change
  • Loss of soil fertility
  • Impact on human health
• How to reduce soil pollution:

  • Reforestation
  • Controlled farming practices
  • Bioremediation
  • Reduce, recycle, and reuse
  • Use biodegradable products
  • Reduce the use of pesticides and fertilizers
  • Use of sanitary landfills
• Pollution environments:

  • Need to raise awareness of threats posed by pollution
  • Importance of understanding pollution, its causes, and impacts on the environment, food, water, and health
• Food, soil, and pest management:

  • World food and nutrition statistics
  • World hunger and malnutrition causes
  • Food security definition
  • Chronic undernutrition, malnutrition, overeating, and obesity
  • How food is produced using industrialized and traditional agriculture
• Industrialized crop production:

  • Relies on high-input monocultures
  • Heavy equipment, large financial capital, fossil fuels, water, commercial fertilizers, and pesticides
  • Goal to increase crop yields
• Traditional agriculture:

  • Relies on low-input polycultures
  • Polyculture benefits over monoculture
  • Green revolution and its impact on global food production
• Gene revolution:

  • Crossbreeding and genetic engineering to produce new crop and livestock varieties
  • Use of genetically modified organisms (GMOs)
• Fish and shellfish production:

  • Fully-exploited, over-exploited, and under-exploited fisheries
  • Aquaculture and the Blue Revolution
• Environmental problems from food production:

  • Soil erosion and degradation
  • Desertification
  • Irrigation water shortages
  • Air and water pollution
  • Climate change
  • Loss of biodiversity
• Pesticides and pest management:

  • Natural enemies control pests
  • Use of pesticides and biopesticides
  • Advantages and disadvantages of conventional chemical pesticides
  • Pesticide resistance, resurgence, and replacement
  • Alternatives to using pesticides like integrated pest management (IPM)
• Producing food more sustainably:

  • Efficient resource use
  • Decreasing harmful environmental effects of industrialized food production
  • Soil conservation techniques like terracing, contour planting, strip cropping, windbreaks, and conservation tillage
  • Restoring soil fertility through organic and inorganic fertilizers, crop rotation
• Biodiversity is the variety of life on Earth and the essential interdependence of all living things
• Levels of Biodiversity:

  • Genetic Diversity
  • Species Diversity
  • Ecosystem Diversity