Terrestrial vs Aquatic food production systems

We have already discussed these two. Let’s continue the roll and compare directly one and another.

Terrestrial

• First levels are more energetically efficient
• Solar energy capture (GPP) more efficient
• Energy transfer between trophic levels not as efficient

Aquatic

• Food is harvested from the top trophic levels, such it lacks from energy

 

• GPP is lower because of the water barrier

• The transfer between trophic levels is most efficient.

MEDC’s vs LEDC’s food availability

 

Since the start of this month, we have been talking about food supply and food production. As we already know some of the general issues and concepts, we’ll now compare the specific situation that MEDC’s and LEDC’s are undergoing.

MEDC	LEDC
Cost of staple food is relatively cheap	Price fluctuation of staple food
Purchase make based on taste and preference	Purchases are made on nutritional need and affordability
Produce seasonality for mostly disappeared due to globalization	Political and economic agendas can affect food production
Average caloric content.   3314	Average caloric content.    2666

All of these differences put the LEDC’s as the more likely to suffer from malnutrition and undernutrition. This scenario is affected by distribution and politics.

Food Production and Distribution

 We have already begun talking about the food supply and its unequal distribution. Now let’s discuss the issues arose by this problem and how do they are handled.

Stuff and terms that you might want to know 

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.

*This two guys are directly related to the poverty and most be treated by the government in order to secure the insecure and maintain the security.

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Undernutrition. The food consumed doesn’t provides enough energy.
Malnutrition. Food has enough energy but lacks certain essential vitamins, minerals or proteins.
Overnutrition. The food consumed exceeds energy use and causes excess of body fats. Yeah… Not big deal in the LEDC’s but we need to take it into account.

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Some of the essential components needed to avoid malnutrition are: Lack of Iron: “Derives into a case of anemia (lack of iron). Increases fatigue, risk of infection and mortal danger at childbirth”. It is necessary for the hemoglobin which captures oxygen and derives it around the body. Lack of Vitamin A. “More likely to get sick or die of common infectious diseases (flu, diarrhea, measles). Blindness” - retina, thus eye-sight dependents on it Vitamins are nutrients, but a catalyzer to the absorption of nutrients. Lack of Iodine. Affect the processes of the metabolism. It causes stunted growth, metal

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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. It is typically generated by a catastrophic event.

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*It is important to analyze famines’ impact over societies and the environment. Obviously there is a great disruption over the social structure of the community. Food becomes the main asset and its acquisition the final goal. The power if for whom has the control over the limited food supply. The environment is harmed by the reaction of the population against the famine. People start to slaughter their livestock and grains and, instead of rationalized it, they finished up the remaining food supply.

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Now that we know what’s the roll with this terms we can analyze the situation and present the actual management of the issues.

ACTUAL SCENARIO

We have already discuss the possible causes of this unequal food distribution in a previous blog entry. Let’s extended this explanation.

Our food supply is generated in both terrestrial and aquatic systems.

From the terrestrial systems we get grains and other crops, and livestock. Most of the world population’s diet is based upon wheat, rice and corn. As the income of certain sectors of the population increases, more meat and livestock's derivate products, such as milk and cheese, are consumed.

Aquatic systems generate food supply based on fish and shellfish.

It depends on the resources of each community or country which is its main source of food. But these three are the BIG THREE of food supply.

Now, the roll must go back a little bit. By talkin’ about the terrestrial systems of food production, we must take into account the different agricultural techniques that are being used…

Imbalanced Food Supply

As we have studied, human population differs a lot from all of the other organisms’ population. This is basically established because the economic model that build up our society determines the distribution of the resources. We are governed by the world’s currency and the capitalism. This, combined with the environmental conditions that make up a biome, are mostly the reason of the gap that has been established between countries in different economical levels. This gap is presented also in the FOOD SUPPLY.
It is important to establish that in fact, there IS enough food in the world BUT there is gross imbalance in its distribution. The imbalanced repartition of food supply leaves part of the people of different countries, or even inside the same country, in precarious conditions.

FOOD FACTS

• World food production is concentrated in the northern hemisphere temperate zones.
• There are approximately 3 chickens for every person.
• 90% of land is not adequate for crops.
• LEDC’s have 80%of the population but eat only 56% of the world’s meat.

In the LEDC’s where a greatest part of the population has no an appropriate access to the food supply, we can find cases of undernutrition and malnutrition

Undernourished those that do not obtain enough energy from the food they eat

Malnourished those whose food has enough energy but lacks certain essential vitamins, minerals or proteins.

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Stick to the roll in order to find more about food supply. Techniques, needed measures and new concepts will be reviewed in the next posts…

Population Pyramids

They are a useful graphic, also called age-sex pyramids, representation that give us the information to analyze population distribution and population change

Population numbers are the x-axis and age groups are on the y-axis.

*As we can see it can also be focused on only one sector of the population.

It shows:

• How many individuals are alive in different age groups cohorts in a country or region for any given year.
• Show the male-female ratio

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Types of Pyramid Shapes.

Stage 1. Expanding – High CBR *(, rapid fall in each upward age group due to high CDR, short life expectancy.

Stage 2. Expanding – High CBR, fall in

CDR as more individuals live to the middle age, slightly life expectancy.

Stage 3. Stationary – declining CBR, low CDR, more individuals live to old age.

Stage 4. Contracting – low CBR, low CDR, higher dependency ratio (those that cannot work), longer life expectanxy

LEDC’s tend to be in stage 1 and 2, while MEDC’s are in the 3 and 4 stages.

Population growth and food shortages.

Thomas Malthus and Ester Boserup theories
Both theories relate food supply with population size, based on the agricultural methods used for food production.
Malthus Theory:

• Published in “The Principle of Population” in 1798
  
• It presents an approach focusing in the population size being determined by the availability of food
  
• Population growth follows a geometric progression and food growth follows an arithmetic one.
  
• When food supply is scarce, population size will adjust to it.
  
• Food production incensement is a slow and difficult process.
  
• It states that controlling population growth is easier than increasing the food supply.

Limitations:

• The theory doesn’t present the possibility of controlling the human birth rate, but establishes a extremely pessimistic approach where organisms of the human population will just die until food supply is enough.
• It doesn’t consider all of the changes that the industrial revolution brought.

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Boserup Theory:

• Presents a model of population in which the size determines the amount of food available.
  
• When there’s stress in relation between food supply and population size, people will always find a way to increase production.
  
• Workforce, machinery and fertilizers are the methods applied to increase food production.

Limitations:

• At first, when population is low, lands are used intermittently, using fallowing (the burning of crops) to make lands more fertile. It is when population increases, that lands are used in a scheduled way. However, this requires more effort in maintaining the land.
• The more maintenance, the more agricultural innovation, but labor increases towards farmers.
• This tends to increase workforce but decrease crop efficiency, a process Ester calls ‘agricultural intensification’.
  
  

Measures of Population Changes

Population change around time by the action of factors such as birth and death rate and migration.

The basic rate for measuring the fluctuations in population are the following:

Crude Birth Rate (CBR)

The number of births per 1000 individuals in a population per year.

Number of births x 1000

population size

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Crude Death Rate (CDR)

The number of deaths per 1000 individuals in a population per year.

Number of deaths x 1000

population size

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Natural Increase Rate

NIR = (CBR - CDR) / 10

Doesn’t consider immigration and emigration.

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Doubling time

The time in years it takes a population to double its size.

Doubling time = 70 / NIR

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Total Fertility Rate (TFR)

It is the average number of children that each woman has over her life time. It shows the potential of population change.

• A TFR > 2.0 results in a population increase
• A TFR < 2.0 results in a population decrease
• A TFR = 2.0 results in a stable population

In developing countries, the fertility rate is usually higher than in MEDC’s

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Humans impact on the environment is not just given out by its growth, but also by resource use and pollution. It’s impact is affecter by:

• It’s affected by the amount of wealth
• Resource desire
• Resource need

Individuals in a population, specially in a human population, interact with the environment in different ways. We cannot generalize for all the organisms within a population.

Wait for a detailed list of identification of resource use and waste profiles in a further post.