Biomass and Biofuels

Where do they come from?



The main source is the corn; in the US it is used to produce ethanol which is
then blended with gasoline to make a greener fuel that produces less CO2. After the extraction of ethanol some byproducts were wastes but recent research has found out that those might have energetic properties as well.

Methods of production

•Combustion- biomass is burned to produce energy.
•Pyrolysis- Biomass materials decompose.
•Gasification- turns into gas some parts of the solid biomass.
•Digestion and fermentation- Bacteria in power plants convert wastes into gas.

Common Uses


•Ethanol
•Methanol
•Fertilizers
•Biogas
•Bioethanol
•Biobutanol
•Biodiesel


Sources-

•"Where is biomass energy found?." Centre of Energy. Centre of Energy TM, n.d. Web. 9 Nov 2010. <http://www.centreforenergy.com/AboutEnergy/Biomass/Overview.asp?page=5>.

•"How biomass energy works." Clean Energy. Union of conserned scientists, n.d. Web. 9 Nov 2010. <http://www.ucsusa.org/clean_energy/technology_and_impacts/energy_technologies/how-biomass-energy-works.html>.

•"Biomass energy – Part Of A Sustainable Future?." Alternate Energy Sources. N.p., n.d. Web. 9 Nov 2010. <http://www.alternate-energy-sources.com/biomass-energy.html>.


Undernutrition, malnutrition and overnutrition.

21:17 Publicado por fer*=) 0 comentarios
Undernutrition, malnutrition and overnutrition


There are several types of nutritional problems and for us to be able to detect them and solve them we should know the differences between them.

  • Undernutrition means that people cannot grow or buy enough energy to meet their basic energy needs.
  • Malnutrition means that people have deficiencies of proteins, calories or other key nutrients
  • Overnutrition occurs when food energy intake exceeds energy use and causes excess of body fat.

Population Pyramids

21:10 Publicado por fer*=) 0 comentarios
Types of  Population Pyramids


In order to understand how population pyramids work we should know they are 3 types of pyramids:
  • Expanding- They have a triangular shape, and they indicate high birth rate, usually due to lack of education and contraceptives and a high death rate due to the lack of medicines and a poor health system. They indicate a poor standard of living.
  • Stable- They have an elipse shape and they indicate a low birth rate due to education and access to contraceptives and a low death rate because of the access to medicines and doctors. They indicate a good standard of living.
  • Contracting- This pyramids usually show the population of a high developed country, this can be seen in the trend of decreasing the birth rate in the country.


Source
http://www.cdli.ca/courses/geog3202/unit06_org03_ilo02/b_activity.html

CBR, CDT and NIR

In order to understand and analyze the growth in population we should be able to get the Crude Birth Rate, Crude Death Rate and Natural Increase Rate. Here are the formulas in order to calculate them.


CBR= (Total number of births/total population) X 1000
CDR=(Total number of deaths/total population) X 1000
NIR= (CBR-CDR) X 10

Malthus and Boserup´s Theories

18:20 Publicado por fer*=) 0 comentarios
In order to understand the relationship between the resources production and the population growth we can use one of this theories:


Malthus Theory

            · Based on population explosion, evident in the 18th century.
            · States that the population will grow faster than the food supply.
            · Population will grow until overpopulation is reached, and any further population growth will result in a population crash due to famine, disease, or war.
            · Stated that the only solution was birth control
            · It doesn’t mention the relationship between population and subsistence, in which when the population grows, the subsistence decreases and when the population decreases the subsistence increases.
            · The equation for the total population is been added a lot of factors in the resent years such as technological improvements, biotechnology, the unpredictability of nature, and sheer luck.
                The Malthusian Theory assumes that all the factors that have an effect on the population remains the same over time.

Boserups`s Theory
  • ·      Wrote on 1968
  • ·      An increasing population will make technologist to increase the production on food.
  • ·      War and famine will be prevented by solutions proposed by humans.
  • ·      Raise population= Increase on demand of foodà change agrarian technology to increase the amount of food.
  • ·      ¨Necessity is the mother of invention¨
  • ·      Assumes that as the population grows, new inventors will solve the problems cause by the over population and will create a sustainable world for a growing population.
  • ·      Its limitation is that the theory is only based on closed communities, which do not exist because of the emigration and immigration of species in a community. 


"Compare and contrast the population theories of Malthus and Boserup ." Thinkgeogwiki . N.p., Oct 2008. Web. 29 Sep 2010. <http://thinkgeogwiki.wikispaces.com/Malthus+vs+Boserup>.


 Wolfgram, Ann. "Malthusian theory explained." Population resources and environment. Population Research Institute, n.d. Web. 29 Sep 2010. <http://www.voxfux.com/features/malthusian_theory/malthusian_theory.htm#1.%20MalthTheory>





Types of resources

18:11 Publicado por fer*=) 0 comentarios
In our world we have 4 types of resources:

  • Renewable: Can be renewed. Example-Oxygen
  • Non-renewable: Can´t be renewed and exist in finite amounts on earth. Example- Fossil Fuels
  • Replenish-able: Between renewable and non-renewable. They are replaced after a long period of time. Example- Ground water.
  • Recyclable resources: Resources that after being used can become into other material. Example-Paper

Abiotic and Biotic Factors

18:03 Publicado por fer*=) 0 comentarios
You can measure the changes in an ecosystem using biotic or abiotic factors...but...what´s the difference between this 2?


Abiotic factors are factors that don´t include living things. 
Some examples are: 

  • Temperature
  • Sunlight
  • Water 
  • Soil
  • Natural Disasters
On the other side we have biotic factors, that are the ones involving living things. 
Some examples are:
  • NPP
  • GPP
  • Biomass
  • Biodiversity 


Suscribirse a: Entradas (Atom)