Sunday, February 6, 2011

Global Warming Opposing Viewpoints

Since the first articles and documentaries about Global Warming were released, different groups have expressed their viewpoint on the subjects. Many different opinions have been stated, all of them supported by different data. These are some of them.

Viewpoint
Characteristics
Global Warming is serious and is caused by humans
The increase of CO2 in the atmosphere, due to the burning of fossil fuels, has increased the amount of heat in the Earth. It states that these changes in temperature and climate are lethal and if they are not stopped or slowed they can destroy our civilization
Global Warming is happening but we're not the problem
Geothermal activity and Volcanoes are the cause of the increase in Greenhouse Gasses, which show that they are causing Global Warming
Global Warming is Natural and it happens every certain time
Through the Earth's history records show that every certain amount of time the global temperature increases and then decreases. This is why Ice Ages have been recorded. Since it is natural all the hysteria created should be ignored.
Media Hysteria
The media has exaggerated facts to make the problem look a lot more serious than it is.

I believe that the Earth does have its temperature changes but we are affecting the environment with the burning of fossil fuels and other activities. I believe that we are accelerating the Earth's temperature increase.

Monday, January 24, 2011

Challenges in Pollution Management

Three level model:
  • Human activity producing pollutant
    • Altering human activity through education, incentives and penalties to promote :
      • Development of alternative tech
      • Adoption of alternative lifestyles
      • Reducing, reusing and recycling
  • Release of pollutant into environment
    • Regulating and reducing points of emission:
      • Standards
      • Measure to extract pollutants from emissions
  • Long-term impact of pollutant on ecosystem
    • Cleaning up pollutant and restoring ecosystems
      • Extracting and removing pollutant from an ecosystem
      • Replanting and restocking animal populations

Wednesday, January 19, 2011

Pollution Mangement

Pollution management focuses on detecting and monitoring of pollution it may be divided as followed:



Directly or indirectly
  • Directly
    • Measuring the concentration of pollutants
      • Acidity on rain
      • Amount of gas(ses)
      • pH of soil
      • Presence/concentration of nitrates/phosphates/sulfates/etc.
        • Amount od organic matter in soil/water
          • Amount of bacteria
            • Concentration of (heavy) metals
            • BOD: used to determine the pollution in water (>BOD, more pollution)
            • Direct sampling
              • In situ
                • Reliable but instruments may be hard and costly to transport
                • Ex situ
                  • Wider variety of methods and instruments
                  • May be repeate
            • Indirect
            • Indicator Species
            • Biodiversity
            • BOD
            • Spectroscopy
            • Chromatography

              Sunday, January 16, 2011

              Major Pollutants


              Pollutant
              Causes
              Effects on health and environment
              Ozone
              Formed when nitrogen and volatile organic compounds mix in sunlight. Nitrogen oxide comes from burning fossil fuels.
              Frequent asthma attacks, sore throats, coughs and breathing difficulties. Hurts plants and crops.
              Particulate matter
              Particulate matter can be divided into coarse particles and fine particles. Formed form sources like road dust, sea spray, and construction. Fine particles are formed when fossil fuels are burned in automobiles and power plants
              Can enter the lungs and cause health problems. Including frequent asthma attacks and respiratory problems
              Lead
              Comes from cars in areas where unleaded gasoline is not used. May be formed in power plants and  other industrial sources but is also contained in lead paint which may pollute water which is transported in lead pipes.
              Toxic air pollutants can cause cancer. Some toxic air pollutants can also cause birth defects. Other effects depend on the pollutant, but can include skin and eye irritation and breathing problems.
              Greenhouse gases
              Carbon dioxide is the most important greenhouse gas. It comes from the burning of fossil fuels in cars, power plants, houses, and industry. Methane is released during the processing of fossil fuels, and also comes from natural sources like cows and rice paddies. Nitrous oxide comes from industrial sources and decaying plants.
              The greenhouse effect can lead to changes in the climate of the planet. Some of these changes might include more temperature extremes, higher sea levels, changes in forest composition, and damage to land near the coast. Human health might be affected by diseases that are related to temperature or by damage to land and water.

              Waste and Pollution

              What is pollution
              • The presence of waste or agent which has increased and reached a point where it can't be managed and harms the environment
              Types of pollution
              • Point source
                • Can be tracked to a particular source
              • Non-point source
                • Does not have a single source
                  • Red tide
              Pollution management
              • Problem since the industrial revolution
              • Popular in the late 20th century
              Sources per type
              • Water
              • Air
              • Soil

              Type
              Point Source
              Non-point Source
              Water
              Municipal Sewage Treatment Plant Discharges for chemical agents and organic matter
              agricultural and urban runoff

              Industrial Plant Discharges may include metals and chemicals which change water's pH
              runoff from mining and construction site
              Air
              power plants, smelters, industrial and commercial boilers
              On road mobile sources like cars and trucks

              wood and pulp processors, paper mills, industrial surface coating facilities, refinery and chemical processing operations, and petroleum storage tanks
              natural sources such as windstorms and fires
              Soil
              Agricultural Pesticides
              Runoff

              Population Sustainability

              Countries around the world are searching for a sustainable population to face the continuous changes in population dynamics. Australia and Japan has established several policies to control their population and ensure that enough people will cover the growing percentage of aging people. These are the policies which have been established in each country:

              Australia
              Japan
              • Immigration policies will change so visas are easier to get and more SKILLED workers arrive
              • Infrastructure will be generated in most populated areas
              • Connections with international companies
              • Increase food production and reduce resources used
              • Relocate and decrease population in overpopulated areas
                • Angel Plan to increase births because of decreasing fertility rate
                • Increase food production to reduce imports
                • Relocation to reduce population in the capital and cities like Kyoto
                • Free child care near train stations to help working parents
                • Reduce costs in basic products to help families and motivate

                  Friday, October 15, 2010

                  MEDCs vs LEDCs

                  MEDC
                  LEDC
                  The cost of sample food items are relatively cheap
                  Staple food items may not be always affordable as prices fluctuate
                  Most people make purchases based on taste and preference
                  People tend to make purchases based on nutritional need and affordability
                  Produce seasonality has mostly disappeared due to globalization
                  Political and economic agendas can affect food production
                  This has also allowed for a greater international variety in most supermarkets
                  Even if food crops are not used as cash crops, food production is still impacted since arable land
                  The average caloric content per capital per day of food is 3314 calories. In the USA specifically, this number is 3774 calories
                  In LEDCs the average caloric content per capital per day of food is 2666 calories. In Eritrea this number is 1512 calories


                  Food consumption


                  MEDC
                  LEDC
                  Meat
                  12.9
                  7.3
                  Fish and Seafoods
                  1.4
                  0.9
                  Cereals
                  37.3
                  56.1
                  Vegetables, fruits, fats
                  48.4
                  35.7

                  The American Association for the Advancement of Science suggests that there is an average of 2790 calories available each day for every human on the planet. That is enough to feed everyone.


                  If food production has kept up with population growth, why are there still so many problems with famine, hunger and malnutrition?

                  Factors to consider
                  • Distribution:
                    • If countries like Canada, USA, and Australia have an excess to food, can that be shipped to Bangladesh, Ethiopia, or Sudan? Who will pay for it? Do they even want that kind of food?
                  • Politics
                    • If excess food is not paid for, is the receiving country in debt of the donating country
                  • So far, food supply has kept pace with human population growth, seemingly refuting Malthus… however recently some are doubting if this can continue
                  • As we adapt an increasing amount of global NPP to human needs. use and degrade more land, eat more meat, contaminate more water, we are getting closer to the planet's K... we just don't know that this is yet.
                  • There are 1.1 billion people living in poverty... They are increasing and growing hungrier.
                  Annual grain yields per hectare have slowed their rate of increase since the Green Revolution (1990-2000 had the lowest increase since before the 1950s).

                  Food Supply

                  Important Terms


                  Food security: This expression means that every person in a given area has a daily access to enough nutritious food to have an active and healthy life.
                  Food insecurity: The opposite of the first one. There are not enough food supply or simply people have not the needed resources to access them.


                  Undernutrution
                  Malnutrition
                  Overnutrition
                  Food consumed doesn't provide enough energy
                  Food has enpugh nergy but lacks nutrients, vitamins, proteins  and minerals
                  Food consumes has an excess of energy than the one needed and used

                  Basic Nutrients which cause malnutrition:

                  Vitamin A
                  Iodine
                  Iron
                  Blindness and children become prone to infection
                  Afects metabolism processes and causes stunted growth and may lead to goiter
                  Anemia, fatigue , risks of infection and increases risk for hemorrhage in labor.


                  Famine: A famine is a situation of severe shortage of food supply in an area accompanied by mass starvation, many deaths, economic chaos, and social disruption. 

                  Wednesday, October 13, 2010

                  Population Pyramids

                  Demographic Transition Model
                  • DTM describes the pattern of decline in mortality and natality (fertility) of a country due to social and economic development
                  • Can be described as a 5-stage model
                    • Pre-industrial
                    • LEDC
                    • Wealthier LEDC
                    • MEDC-stable
                    • MEDC-population decline


                  Sunday, October 3, 2010

                  Environmental Economics

                  • How do we value resources
                    • Economic --> money
                    • Ecological --> support systems
                    • Scientific --> research
                    • Intrinsic --> cultural
                  • Natural capital
                    • Natural resources, services, and processes
                    • Natural income
                  • Types of natural capital
                    • Renewable
                      • Replace or restock themselves
                    • Non-renewable
                      • Exist in finite amounts on the planet
                    • Replenishable
                      • Between renewable and non-renewable
                      • Example Groundwater
                    • Recyclable
                      • Resources that can be transformed into usable materials after already being used for something else
                      • Iron, aluminum, etc
                  • Sustainability
                    • Living within the means of nature, on the "interest" or sustainable natural income generated by natural capital.
                    • However, economist and environmentalists may have very different views on what is sustainable
                    • Any society that supports itself in part by depleting essential forms of natural capital is unsustainable.

                  Population and Resource Use

                  • Population size is not the only factor that determines our species' impact on the environment
                    • Amount of wealth, including distribution
                    • Resource desire
                    • Resource need
                  • Many environmental impact models are based on the assumption that all individuals in a population have the same resource use and waste profile and thus impact the environment equally
                  Population Growth and Food Shortages
                  • Thomas Maltus was an English clergyman and economist who lived back in the day (1766-18434)

                  Population Size

                  • Four main factors that affect  population size
                    • Birth rate
                    • Death rate
                    • Immigration
                    • Emigration
                  • The measures of population change are
                    • Crude birth rate (CBR)
                      • The Crude Birth Rate (CBR) includes the number of births per 1000 individuals. So, the formula for this is:
                      • CBR = (Number of births / population size) x 1000
                      • The CBR in the world is 20.3 per 1000 per year.
                    • Crude death rate
                      • The number of deaths per 1000 individuals in a population per year
                      • Calculated by dividing the number of deaths by the size of population and multiplied by 1000
                    • Doubling rate
                      • The time in years that it takes a population to double its size
                        • Doubling time = 70/NIR
                    • Natural increase rate
                      • NIR=(CBR-CDR) / 10
                      • This gives NIR on %
                      • Does not consider immigration or emigration
                    • Total Fertility Rate
                      • The average number of children that each woman has over her lifetime. It shows the potential for population change in a country.
                        • A TRF > 2.0 results in a population increase
                        • A TRF < 2.0 results in a population decrease
                        • A TRF = 2.0 results in a stable population

                  Wednesday, September 29, 2010

                  S and J Curves for Growth Rate

                  S-curves and J-curves
                  • S-curves
                    • Start with exponential growth
                    • Above a certain population size, the growth rate slows down until population stabilizes
                    • Consistent with density dependent limiting factors
                    • Population size stabilizes at the carrying capacity (K) of the environment
                    • The area between the exponential growth curve and the S.curve is called environmental resistance
                  • J-curve
                    • Shows a boom and bust pattern
                    • Population grows exponentially then crashes
                    • These collapses/crashes are called diebacks
                    • Population often exceeds K before the collapse occurs which is referred to as overshoot



                  Growth Rates
                  • S and J curves are idealized
                  • In nature both types of limiting factors act on the same population and the result is an S/J combo curve
                  • The growth rate of the human population is slowing as we reach the K of our environment
                  • Peaked at 2.1% per year in 1965-1970
                  • Now: 1.3% and falling
                  • Back in the day world population was increasing slowly due to environmental resistance, diseases, epidemics, famine, and natural catastrophes
                  • MEDCs and LEDCs
                    • Countries are also economically classified based in the industrial development or GDP
                    • MEDCs
                      • are industrialized nations with high GDPs
                      • Relatively rich population and starvation is unlikely
                      • High Level of resource use per capita
                      • Relatively low population growth rate
                    • LEDCs
                      • are less industrialized or have none at all
                      • May have plenty of natural capital but usually this is exported and processed in MEDCs
                      • Lower GDP and high poverty rates
                      • Large population sector with low standard of living
                      • High population growth rates

                  Population Dynamics

                  Populations change over time due to many factors/variableThese limiting factors may be classified as: Density dependent and Density independent.

                  Limiting factors:
                  • Density dependent
                    • Biotic factors
                    • Effects increase as population increases
                    • Act as negative feedback mechanisms, which function to regulate or stabilize a population size
                    • Internal Factors
                      • Act within a species
                      • Ex. Limited food supply, territory, density dependent fertility
                    • External factors
                      • Act between different species
                      • Ex. Predation and disease
                  • Density Independent
                    • In general tend to be abiotic
                    • Effects are not related with population growth
                    • Not part of a feedback system
                    • Weather, climate, volcanic eruptions, floods

                  Tuesday, August 17, 2010

                  Measuring Biodiversity


                  Biodiversity, according to the Convention of Biological Diversity, is: "the variability among living organisms from all sources including, inter alia, terrestrial, marine and other aquatic ecosystems and the ecological complexes of which they are a part; this includes diversity within species, between species, and of ecosystems." Biodiversity is very important part of the environment since it helps it regulates the balance and the reusing and recycling of energy and materials within the ecosystem.


                  To study a certain area biodiversity needs to be measured. To measure biodiversity, we usually focus on 5 ways: Species richness, species evenness, disparity, species rarity, and genetic variability.

                  • Species richness: refers to the total number of members of a given species in a quantified area.
                  Biodiversity Curve
                  • Species Evenness: he degree to which the number of individual organisms are evenly divided between different species of the community.
                  • Disparity: measures the phenotypic differences among species resulting from the differences genes within a population.
                  • Species Rarity: the rarity of individual organisms within a quantified are.
                  • Genetic Variability: each population of species contributes to additional biodiversity due to variations between genes
                  There are other ways to measure biodiversity that combine richness and equitability. Most ecologist use the Shannon-Weiner or Information index:
                  Biodiversity Index
                  that only means that you need to get the proportion of the specie to the whole and then multiply that number by its natural logarithm. 

                  For additional information go to:

                  Wednesday, August 11, 2010

                  Classifying Organisms

                  Taxonomy
                  Taxonomy is the science of classifying organisms. Carol von Linne, mostly known as Carolus Linnaeus, was the Swedish botanist who began working on a system for the classification of organisms. This system evolved and became the most common system used today. The system consists of organizing different groups which are inside other groups. Each organism would be labeled with a species, related species would be organized in the same genus, similar genera would be in the same family, then families in an order, orders in a class, classes in a phylum (or a division), and phyla in a kingdom.

                  The Kingdoms, which are the largest groups, were only two in the beginning but have developed and now 6 Kindoms are usually accepted: Animalia, Plantae, Fungi, Protista, Monera, Archaea
                  • Kingdom Monera: Prokaryotes; Bacteria; May have fungus, plant, or animal characteristics; includes Eubacteria and Cyanobacteria; around 10,000 species
                  • Kingdom Archaea: Prokaryotes; always unicellular and living under rough or extreme conditions and environments; different chemical characteristics than Monera
                  • Kingdom Protista: Slime molds and algae; mostly unicellular; eukaryote; around 250,000 species
                  • Kingdom Fungi: Mushrooms, molds, mildew; multicellular; heterotrophic; almost never capable of movement; 100,000 species
                  • Kingdom Plantae: Multicellular and eukaryotes; producers of complex molecules using light (photosynthesis); 250,000 species
                  • Kingdom Animalia: Multicellular and eukaryotes; without cell walls which reduces stiffness; unable to produce food, need to take energy from external sources; 1,000,000 species (largest kingdom) 
                  A very important part of the classification are the homologous structures. Internal structures which may be similar to those of other organisms may help classify the groups. Characteristics such as reproduction methods, backbone existence, type of food consumed, body parts and covering, and others may also help in the grouping. There are other three ways of classifying including: systematics, cladistics, and molecular evolutionary taxonomy. Systematics and Cladistics use tree diagrams to explain relationships between organisms and find their way to a common ancestor. The difference between these two is that cladistics usually divide the branches when special traits are found. Molecular Evolutionary Taxonomy classifies by the presence of specific genetic changes in organisms. Still the anatomical classification (Linnaeus method) is the most common. It keeps changing because of the new discoveries available because of new technology.

                  A common example of Linnaeus's method are humans:
                  • Kingdom: Animalia
                  • Phylum: Chordata
                  • Class: Mammalia
                  • Order: Primata
                  • Family: Hominidae
                  • Genus: Homo
                  • Species: sapiens sapiens
                  A species is the one who breed exclusively inside a group and produces fertile offspring. The name of the species would be used with the genus name in the binomial nomenclature to make up the official name of a certain organism. In the past example the species's name would be Homo sapiens sapiens.