ENSC 001 Midterm 2

What are the three aquatic ecosystems?

1) Freshwater
2) Estuaries
3) Marine

Weather

defined by day to day weather

Climate

defined by long term and precipitation

Biome

a large, relatively distinct terrestrial region with similar climate, soil, plants, and animals, regardless of where it occurs in the world.

How many biomes are there?

There are nine major biomes
1)Tundra
2) Boreal Forest
3)Temperate rainforest
4)Temperate deciduous forests
5)Grassland
6)Chaparral
7) Deserts
8)Savanna
9)Tropical rainforest

Biome location is determined by?

It is determined by climate: temperature (which varies with both latitude and elevation) and precipitation.

What happens at biomes at the same latitude?

Even at the same latitude, biomes can change due to precipitation. i.e goes from tropical rain forest to dry tropical desert.

When you go up in latitude what happens to the biomes?

Going up in temperature is the same thing as going up in latitude. You can go from the desert to the peak of mountain.

Tundra (arctic or alpine)

Is a treeless biome in the far north with harsh, cold winters and extremely short summers.

There is a lack of trees due to the lack of precipitation.

Precipitation and Temperature in the Tundra?

Precipitation is extremely low: 10-25 cm/yr
Temperature: (5-50 degrees F)

Tundra soil and productivity?

Nutrient poor soils with little organic material --> permafrost present
There is low primary productivity because there isn't enough energy flow through the food web
Low species richness because vegetation is mostly grass and sedges and the food web is simple

Boreal Forests

A region of coniferous forests in the northern hemisphere, south of the tundra. (Canada and Alaska)

Covers about 11% of the land

Precipitation and Temperature at the Boreal Forests?

Precipitation is 2x more than tundra: 50cm/yr
Temperature (4-60 degrees F) growing season is a little longer than the tundra, about 6 months above freezing temperature.

Boreal forests soil and productivity?

Soil is acidic and mineral poor with patchy permafrost
Vegetation is comprised of drought-resistant conifers
-> white spruce
-> balsam fir
-> eastern larch
Productivity is a little higher compared to tundra...
mostly small animals and migrating birds, a few larger animals such as caribou and moose are present

Temperate rainforest

Coniferous biome with cool weather, dense fog and high precipitation. (Northwest US: Washington and Oregon)

Precipitation and Temperature in the temperate rainforest?

There is about 127cm/yr = lots of precipitation
rain is heaviest during the winter
Temperature: Winters are mild and Summer are cool (42-60 F)

Temperate rainforest soil and productivity?

Soils are nutrient poor, but high in organic material because of dropped needles. The soil is nutrient poor because cool temperature slows decomposition.
Dominant Vegetation: Large evergreen trees, old-growth forest
Productivity: Very high species richness, variety of cool climate animal life

Temperate deciduous forests

Forest biome that occurs in temperate areas with a moderate amount of precipitation. (Entire East Coast)

Precipitation and Temperature in the temperate deciduous forests?

Precipitation: 75-150cm/yr
Temperature: Seasonality, the biggest difference from everything else:
hot summers (extremely humid bc more moisture in the air 89%)
cold winters (37 degrees)
Spans from 37-77 degrees F

Temperate deciduous forest soil and productivity?

Topsoil is rich in organic material and underlain by clay
vegetation is primarily deciduous
--> oak, maple, beech
animals
--> deer, bear, small animals
biome has been regenerated after farming and timber harvest

Grassland

grasslands with hot summers, cold winters, and too little precipitation to support trees
90% of this biome has been lost to farmland (middle of US), this is because it's flat and you don't need to knock down trees

Precipitation in the Grassland?

25-75 cm/yr tall grass prairies and short grass prairies
temperature (23-55 degrees)

Grassland soil and productivity?

Soil has thick, organic material rich organic horizon, periodic fires prevent tree and shrub growth.
Animals: Used to be covered with bison (no more), smaller animals are still present (e.g. prairie dogs)

Chaparral

Called a Mediterranean Climate seen in Southern California and Greece

Temperature at Chaparral

Mild and moist winters
Hot and dry summers
Frequent fires
(52-74 degrees F)

Chaparral soil and productivity?

Soil is thin and often not fertile
Vegetation: dense growth of evergreen shrubs, lush during the growing season
Animals: Mule deer, chipmunks, many species of birds

Deserts

Biome where lack of precipitation limits plant growth

Temperature and Precipitation in the Desert

Temp can vary greatly in 24hr period as well as yearly based on location (43-77F)
Precipitation less than 25cm/yr

Desert soil and productivity?

Soils low in nutrients and high in salts
Productivity is low (primary) , vegetation is sparse (cacti and sagebrush), animals are very small to regulate temperature, not a lot of species diversity

Savanna

Tropical grassland with widely scattered trees
located in Africa, around the equator

Temperature and Precipitation in Savanna

Temperature varies little throughout the year (55-77 deg F)
Precipitation seasons regulated by precipitation, not temperature (76-150cm/yr)
Not as much rain as other forests, prone to fires
during the summer very little rain

Soil and Productivity in the Savanna's

Soil low in nutrients due to leaching
Vegetation --> wide expanses of grass, occasional Acacia trees, fire adaptive characteristics
Animals --> herds of hoofed animals, large predators - lions, hyenas

Tropical rainforest

lush, species-rich biome that occurs where climate is warm and moist throughout the year. Around equator (south america, amazon)

Precipitation tropical rainforest

200-450cm/yr
rains in summer, dry in winter
precipitation is much higher despite same latitude and roughly same temp

Productivity and soil in the tropical rainforest

Very productive
Most species-rich
Ancient, weathered, nutrient-poor soil --> nutrients tied up in vegetation, not soil
Vegetation --> 3 distinct canopy layers
Animals --> most abundant insect, reptiles and amphibians on earth

Vertical Zonation

increasing in elevation has similar effect on ecosystem as traveling to higher latitudes

Aquatic Ecosystem

Fundamental division: Freshwater (no salt) , Saltwater
Aquatic ecosystems are affected by: Dissolved oxygen level, light penetration, pH, presence/absence of currents

3 main ecological categories of organisms

Plankton - free floating (the current moves them)
--> Phytoplankton - photosynthetic
--> Zooplankton - animal-like
Nekton - strong swimming
Benthos- bottom dwelling (crabs and lobsters that hang at the bottom)

Freshwater ecosystems

Rivers and streams (lotic or flowing waters)
Lakes and ponds (lentic or standing water)
Marshes and swamps (standing water)

--> represents 2% of earth's surface
--> assist in recycling water back to the oceans

River continuum concept

Everything begins at the little headwater streams
water moves from headwaters to rivers to coastal ocean

change in physical features and food sources (abiotic differences)
results in change in biological features and ecosystem function
in streams, organisms adapted to fast flowing water (hooks, suction, flattened bodies)
in rivers, adaptation for swimming (streamlined)

Lakes and ponds

Body of freshwater that does not flow
3 zones
Littoral Zone, Limnetic Zone, Produndal Zone
Experience thermal stratification (depending on depth)

Littoral Zone

shallow water area along the shore

Limnetic Zone

open water beyond the littoral zone

Profundal Zone

beneath the limnetic zone of deep lakes

Thermal stratification

temperature changes sharply with depth
thermocline

Thermocline

Temperature transition between warmer surface water and colder water at depth (difference in density)
only present in warm months

Marshes and swamps

land with shallow, fresh water for at least part of the year
characteristic soil and vegetation
were once regularly filled
recently--> ecosystem services have been better recognized
----> flood protection, water filtering, etc.

Estuaries

Where freshwater and saltwater mix
eflux of fresh water going out, salt water coming in
Highly variable environment: Temperature, salinity, depth of light penetration
Highly productive: nutrient transported from land, tidal action circulates, high level of light penetrates shallow water, plants provide photosynthetic car

Salt Marshes

usually in temperate estuaries
shallow wetlands dominated by a few species of salt tolerant grasses --> seen as worthless, filled in, and constructed over
services are extensive --> buffer land from storm energy, large cycling of organic matter for coast, habitat (particularly birds)

Marine ecosystem

pelagic environment --> shallower depths
subdivided into life zones
-intertidal zone
-benthic zone
-pelagic environment (neritic and oceanic provinces)

Intertidal Zone

where salt water meets land
area of shoreline between low and high tide
biologically productive habitat
Stressful habitat --> splash zone, wave action, flooding, drying out

Benthic Zone

bottom of the ocean
ocean floor, extending from tidal zone to deep sea trenches
sediment is mostly mud --> burrowing worms and claims
3 zones: Bathyal, Abyssal, Hadal

Bathyal zones

200m - 4000m deep

Abyssal zones

4000m - 6000m deep

Hadal zones

6000m - bottom of deep sea trenches

Pelagic environment

all of the open ocean water, main divisions based on depth and light penetration

Euphotic zone

surface to 150m
sufficient light for photosynthesis; organisms are all floaters or swimmers

Neritic province

Organisms are floaters or swimmers (zooplankton, whales)
water that overlies the continental shelf (to depth of 200m)
hypothermal vents

Oceanic province

Water that overlies depths greater than 200m
Organisms are filter feeders, scavengers and predators
--> no light for photosynthesis, organisms adapted for darkness
--> marine snow (food particles falling from euphotic zone) support some life

Human impacts on the ocean

Nonpoint Source Polution, Invasive Species, Overfishing, Bycatch, Aquaculture, Point Source Pollution, Coastal Development, Habitat Destruction, Climate Change

What are the two indicators for human health?

Infant morality and Life expectancy

Infant mortality

how many children die before age of 1 year per 1,000 births (measured at county, state, region, and country levels)

Life expectancy

how long people are expected to live

Does life expectancy and infant mortality vary between industrialized vs. developing countries?

Yes!
It depends on access to basic necessities ( education, food, clean water, electricity, etc.)
It also depends on access to healthcare and public health services (prevention, medicine, antibiotics, vaccines, etc.)

Infant mortality rate (per 1000) by country (2013)

Industrialized countries have low infant mortality rates
Developing countries have very high infant mortality rates because they don't have access to health care and needed necessities (Africa)

Infant Mortality Rate (1950-2015)

in the US in 1950 it was about 32 but went down to 10 (pretty low)
whereas india went from 185 to about 50 (still high)
afghanistan ent from 245 in 1960 to about about 75 in 2015 (extremely high still)

Average life expectancy by country (years)

Industrialized countries (especially those with universal health care) have higher life expectancy about 70-80yrs old
Emerging countries have life expectancy from anything from 64 to under 40 yrs old (parts of Africa)

Life expectancy in the US Counties

Coastal counties have higher life expectancy than those in the inland countries bc the inland counties have a lower income so less healthcare.

Those that live near the Mississippi river experience a life expectancy that is almost 20 years less than the highest part of the country (around 60yrs). Many public health issues and is a very poor low income area.

Life expectancy vs. household income within the US

Those that have a lower income die earlier... women die less early than the men that are in the same lower income conditions

Those that have a higher income die later... women and men have a smaller gap difference

Women top percentage income: 88.8 yrs
Women bottom percentage income: 78.5 yrs

Men top percentage income: 87.3 yrs
Men bottom percentage income: 72.3 yrs

What is health like in highly developed countries?

Health is relatively good --> avg life expectancy for men is 75 and 80 for women

the leading causes of death are chronic (associated with living longer)
--> cardiovascular disease (24%) and cancer (23%)

some premature deaths are caused by lifestyle
--> poor diet, lack of exercise, and smoking
--> obesity and aging are major risk factors

Body mass index (BMI)

BMI = (Weight x 703) / Height^2

Weight in pounds, height in inches
BMI categories
underweight less than 18.5
healthy 18.5-24.9
overweight 25-29.9
obese over 30
(not accurate for muscular people)

Why is obesity in men over 18 more common in industrialized countries?

More common in industrialized countries (North America) because industrialized countries have access to excess food and a more sedimentary lifestyle compared to those from emerging countries

Obesity rates by US counties

Once again coastal counties are not as bad, there is a very noticeable difference in the southeast counties because almost 50% of pop. is obese, they have higher obesity, higher cardiovascular disease, and lower incomes.

Cardiovascular Disease Mortality Rates by US counties

Coastal counties not as much, increased a lot in south east areas and inland areas. (due to lower income)

Cancer rates by country

Industrialized countries have higher rates of cancer because cancer is the disease of the old... the longer you live the greater your odds of getting cancer.

Those in emerging countries simply do not live long enough to develop cancer.

What cancer kills the most?

Lung and Pancreatic because it's extremely hard to screen for so it's usually to late to do anything about it.

Breast and Prostate cancer are easy to develop but can usually be caught early enough to treat.

Multistage Carcinogenesis

Technical term that describes how cancer is formed

What are the stages of Multistage Carcinogenesis?

1) Initiation - group of cells that have been exposed
2) Promotion - eventually mutations start to divide
3) Malignant Conversion - becomes more invasive
4) Progression - moves away form original site and goes through the blood stream
5) Cancer (metastasis)


This all happens over a long period of time

What is health like in developing countries?

Biggest challenges are malnutrition, unsafe water, poor sanitation
The life expectancy is overall around 65 years but the lowest in the poorest countries are around 45 yrs (bc of AIDS epidemics)
Childhood mortality rate is high --> malnutrition, diarrheal disease, malaria, HIV/AIDS

Emerging disease

-not previously observed in humans
-usually jumps from an animal host
examples: AIDS, lyme disease, West Nile Virus

Reemerging disease

-existed in the past and recently increasing in incidence
examples: tuberculosis, yellow fever, malaria

Why are there emergence/reemergence of diseases?

Evolutions of diseases so it transitions to human hosts, diseases become more resistant to antibiotics, urbanization and crowding, more elderly who are susceptible to disease, pollution and environmental degradation, growth in international travel and commerce, and poverty and social inequality

What is the rate of typhoid fever in the US?

Was high in the 1920s but decreased to almost 0 by 1960 due to treating water supplies properly.

Chlorination was introduced in 1908 to treat drinking water supplies, and chlorine is still the most common disinfectant used in the US

Typhoid fever

Source: injestion of water contaminated with the bacterium Salmonella enterica tyohi

Some Symptoms: Fevers up to 104 degrees, stomach pains, headache, loss of appetite, rash of flat, rose-colored spots

Annual cases
5700 cases per year in the US (75% come from traveling overseas)

21.5 million cases and 200,000 deaths per year in the Developing world

Environmental Pollution and Disease

Difficult to link pollutants to effects on people due to persistence, bioaccumulation, and biomagnification.

pollution contaminates air, water, soil, food --> humans come into contact --> exposure to pollution causes adverse health effects

What are the core disciplines that underpin the field of environmental health?

1) exposure assessment
2) toxicology
3) epidemiology

Persistence

A characteristic of certain chemicals that are extremely stable and may take many years to break down into simpler forms by natural processes.

Natural decomposers (bacteria) have not evolved a way to break it down

Examples: Synthetic Chemicals such as DDT

Bioaccumulation

Buildup of a persistent toxic substance in an organism's body often in fatty tissues
--> synthetic chemicals do not metabolize well and remain in the body for extended periods of time

Polybrominated diphenyl ether (PBDE) is a good example of bioaccumulation because the concentration increases in breast milk over time passes.

Ex #2: As fish fishes grow up they continue to have an increase in contaminant levels

Biomagnification

The increased concentration of toxic chemicals in the tissues of organisms that are at higher levels in food webs

ex: 0.00005ppm in the water --> 0.04 ppm in primary producer --> 0.16ppm in primary consumer --> 0.28ppm in secondary consumer --> 2.07 ppm in secondary consumer ---> 75.5 ppm in tertiary consumer. This is an increase of 1.5 million times

bc of this DDT nearly killed off the bald eagle

travels through the food web

Endocrine disrupters

A chemical that mimics or interferes with the actions of the endocrine system in humans and wildlife
--> ex: PCBs, dioxins, heavy metals (lead and mercury) , DDT

Animals exposed to these chemicals have altered reproductive development and are often sterile

Do endocrine disruptors contribute to rising cancer rates?

Yes, hormonally related cancers are increasing (breast and testicular)
Phthalates have been implicated as potential endocrine disrupters --> which are common ingredients in cosmetics, fragrances, nail polish, medication, toys, and food packaging

Bisphenol A (BPA)

is a potential endocrine disruptor
it is a chemical in hard plastics (baby & drink bottles)
banned in many countries and CA (not in US and Australia)

What is environmental health?

According to the World Health Organization
"Environmental health addresses all the physical, chemical, and biological factors external to a person, and all the related factors impacting behaviors. It encompasses the assessment and control of those environmental factors that can potentially affect health."

Exposure Assessment

Certain measurements out in the field
i.e transmission of covid within a population

toxicology

is the study of the effects of toxicants on the human body

epidemiology

the branch of medical science dealing with the transmission and control of disease

risk assessment

what's the scene, what's the toxicity? Is the risk small or is it actually a problem?

is it economically worth it to work on the risk?

risk management

identifying steps and policies that can help manage the risks

What are some indoor aggregate human exposure?

Inhalation of Contaminated Air, House dust, Drinking Water, Food, Plastics, Flame retardants, Dermal exposure through touching dust

What are some outdoor aggregate human exposure?

Air, Soil, Drinking Water, Recreation water, Food, Outdoor air is going to be driven by ozone exposure, particulate matter, and vehicle emissions.