Introduction to Environmental Science

Introduction to Environmental Science

• Environmental science is an interdisciplinary study of how the Earth works, encompassing interactions with the planet and solutions to environmental issues for sustainable living.
• It is involves ethics, ecology, biology, chemistry, economics, engineering, political science, history, oceanography, sociology, anthropology and archaeology.

Environmental Science vs Environmentalism

• Environmental science is an interdisciplinary field studying human interactions with the environment's living and nonliving components.
• Environmentalism is a social movement focused on protecting Earth's life, often practiced in political and ethical contexts rather than scientific realms.

Sustainability

• Sustainability is the capacity of the earth's natural and human systems to survive and adapt to changing environmental conditions indefinitely.

Principles of Sustainability: Solar Energy

• Solar energy warms the planet and supports food production for plants, humans, and most animals.
• It powers indirect forms of energy, like wind and flowing water, which can be harnessed for electricity.

Principles of Sustainability: Biodiversity

• Biodiversity is the biological variety and variability of life on Earth.
• It encompasses evolutionary, ecological, and cultural processes that sustain life at all levels, from genes to ecosystems like deserts, grasslands, forests, and oceans.
• Species and systems can renew soil and purify air and water.

Principles of Sustainability: Chemical Cycling

• Natural processes recycle nutrients or chemicals.
• The cycle is essential because there is a fixed supply of nutrients on Earth.

Natural Capital

• Natural capital equals natural resources + natural services.

Natural Resources

• Natural resources are materials and energy in nature that are essential or useful to humans.
• Natural resources are classified as renewable, nonrenewable, or inexhaustible.
  • Examples of renewable resources: air, water, soil, plants, and wind.
  • Exmaples of nonrenewable resources: copper, oil, and coal.
  • Example of inexhaustable resources: solar energy.

Natural Services

• Natural services are processes, such as purification of air and water and pollination which is vital.
• Nutrient cycling is one of the vital natural services

Importance of Sustaining Biodiversity

• Provides necessary ecosystem services to sustain human life and ecosystem balance.
• Ecosystem services include:
  • Supporting
  • Provisioning
  • Cultural and Aesthetics
  • Regulating

Ecological Footprint

• Ecological footprint is the amount of biologically productive land and water needed to indefinitely supply people in a particular country with renewable resources and to absorb and recycle the wastes and pollution produced by such resource use.

Ecological Tipping Point

• Ecological tipping point is when a time delay between unsustainable practices and environmental effects can cause environmental problems to build slowly until the threshold, this is also known as.
• Reaching the tipping point often causes irreversible shift in the behavior of natural systems.

Biocapacity and Ecological Deficit

• The Biocapacity of an ecosystem is an estimate of its production of certain biological materials.
• A country's total ecological footprint is larger than its biological capacity to replenish its renewable resources and absorb resulting wastes and pollution, it’s said to have an ecological deficit.

Biome

• Earth biomes are categorized in two major groups: terrestrial and aquatic.
  • Terrestrial biomes are based on land.
  • Aquatic biomes include both ocean and freshwater biomes
  • 8 major terrestrial biomes: distinguished by characteristic temperatures and amount of precipitation

Terrestrial Biomes

• The world's major biomes are distinguished by characteristic temperatures and amounts of precipitation.
  • Examples of terrestrial biomes: tropical forest, boreal forest, savanna, tundra, desert, mountains, chaparral, polar ice, temperate forest, temperate grassland

Aquatic Biomes

• Covers about 75% of earth's surface.
• Divided into 2 categories: freshwater and marine.
• Freshwater: ponds, lakes, rivers and streams.
• Marine: oceans and estuaries.

Productivity

• The amount of biomass that a particular ecosystem can support is determined by how much solar energy its producers can capture and store as chemical energy and by how rapidly they can do so.

Trophic Levels

• Producers (autotrophs):
  • Terrestrial producers: plants (photosynthesis)
  • Aquatic producers: algae and aquatic plants near shorelines, phytoplankton dominant producers in open waters
• Consumers (heterotrophs):
  • Primary consumers (herbivores): feed on producers
  • Secondary consumers: carnivores (meat eaters) that feed on the flesh of herbivores
  • Tertiary consumers: carnivores that feed on other carnivores' flesh
  • Omnivores: can eat both plants and other animals: pigs, foxes, humans
• Decomposers: consumers that release nutrients from dead organic matter

Biomass

• Every level in food chains or food webs contains a certain amount of biomass.
• Biomass the dry weight of all organic matter contained in its organisms.
• Biomass is transferred from one trophic level to another.

Types of Productivity

• The amount of biomass that a particular ecosystem can support is determined by how much solar energy its producers can capture and store as chemical energy and by how rapidly they can do so.

Gross Primary Productivity

• The rate at which an ecosystem's producers convert solar energy into chemical energy in the form of biomass found in their tissues.
• Measured in terms of energy production per unit area over a given time (Kcal/m^2/yr).

Net Primary Productivity

• The rate at which producers use photosynthesis to produce and store chemical energy minus the rate at which they use some of this stored chemical energy through aerobic respiration.
• It measures how fast producers can produce chemical energy stored in their tissue and potentially available to other organisms in an ecosystem.

Population Trends

• Human population growth continues, but its distribution is uneven.
  • At least 95% of the 2.6 billion people likely to be added to the world's population between 2011 and 2050 will live in the least developed countries.
• maximum number of people that live indefinite comfort without decreasing earth's sustainability for the future generation

Philippines Population (2020)

• According to UN data the estimated midyear population was 109,581,078.
• The equivalent to 1.41% of the total world population.
• The Philippines ranks number 13 in the list of countries (and dependencies) by population.
• Area of 298,170 Km2 (115,124 sq. miles)
• Population density of 368 per Km² (952 people per mi²).
• 47.5% of the population is urban (52,008,603 people in 2020)
• The median age in the Philippines is 25.7 years.

The IPAT Equation

• I = P x A x T, which represents Impact = Population x Affluence x Technology.
• The equation represents those factors are intermediate causes, not root causes.

Factors Affecting Population Size

• Birth Rate, Death Rate, Total Fertility Rate, Migration.

Birth Rate

• Crude birth rate is the annual number of live births per 1000 people in the population of a geographic area at the midpoint of a given year and is also known as natality.
• In the Philippines for 2022, a total of 1,455,393 live births were registered in the country, which is equivalent to a crude birth rate (CBR) of 13.0 or 13 births per thousand population. (PSA).

Death Rate

• Crude death rate is the annual number of deaths per 1000 people in the population of a geographic area at the midpoint of a given year and is also known as mortality birth.
• In 2022, a total of 679,766 deaths were registered in the Philippines, a decrease of 22.7 percent from 879,429 in 2021. This is equivalent to a crude death rate of 6.1, or six deaths per 1,000 population in 2022.

Total Fertility Rate

• Used to Estimate of the average number of children per woman born to women of childbearing years (ages 15-44) in a given population in a year.
• Is a Key population size factor.
• Based on the preliminary results of the 2022 National Demographic and Health Survey (NDHS), the total fertility rate (TFR) in the Philippines of Filipino women aged 15 to 49 years declined from 2.7 children per woman in 2017 to 1.9 children per woman in 2022.

Population Migration

• the increase in population size in a certain geographical area that is not caused by natural increase but by people deciding to move with the intent of staying.
  • Immigration – travelling into another
  • Emigration – travelling out of a place

Factors Affecting Population Size

• Availability of family planning and birth control methods.
• Cultural norms surrounding family planning and sex.
• The pandemic.

Economic Factors That Affect Natality and Total Fertility

• Importance of children as a part of the labor force, especially in developing countries.
• Cost of raising and educating children.
• The availability or lack of private and public pension systems.
• Urbanization.
• Educational and employment opportunities for women.
• Average age at marriage.
• Availability of legal abortions.
• Availability of reliable birth control methods.
• Religious beliefs, traditions, and cultural norms.

Factors That Affect Death Rates

• Life expectancy measures a society's quality of life by measuring general level of nutrition and health care.
• Infant mortality rate: The average number of years a newborn infant can expect to live

Age Structure

• A population's Age Structure helps make projections.

Demographic Trends That Lead to Urbanization

• Cities and Migration: An increasing percentage of the world's people live in urban areas.
• Urban Development: Urban areas grow in two ways – births and immigration.
• Urban areas are sprouting everywhere.
• The numbers and sizes of urban areas are escalating

Urban Sprawl

• Urban sprawls affect rural and forested areas.

Solutions

• Urban sprawl, Filipino cities remain behind, suggesting the need for reforms to improve the potential for additional economic growth and job creation in cities.
• Several key issues:
  • Poor business environment
  • Weak infrastructure, land management,and access to markets
  • Low demand for innovation and skill match
  • Limited access to finance and business support
  • Insufficient economic planning

Resource Mismanagement

• Water crisis for domestic and agricultural sectors.
• Energy poverty.
• Land governance crisis leads to congestion.

Natural Capital Degradation: Urban Sprawl

• Land and Biodiversity Loss of.
• Increase in water, energy use, and waste.
• Decline of downtown business districts.