Against the idealism of carrying capacity

A population model assumes that the use of resources is equal to all of the individuals. The think here is that we are talking about “individuals” not hard numbers. They have different needs and life conditions. That’s why we cannot take the entire population of the world as in uniform conditions in order to establish the carrying capacity (K)
The individual/population resource use is a dynamic principle. We also must we aware that resources vary with time and space. Some of this variations are given by:

• MEDCs and LEDCs
• Urban vs. rural
• Young communities vs. older communities

However we need to manage carrying capacity to our advantage.
It might be trough pollution control
POLLUTION MANAGEMET
Natural income –> Human activity –> wastes –>  pollution
Pollution:the addition of a substance of agent to the environment by human activity at a rate grater that that at which it can be rendered harmless by the environment.
Major sources of pollution

• Combustion
• Domestic waste
• Industrial waste
• Agricultural waste

Pollution by noise, by heat.
Sources:

• Point source
• Non-point source

Detection and monitoring

• Directly. measure with a particular variable to refer an specific pollution factor. (CO2 presence in the atmosphere)
• Indirectly. Impact. uses a variable that depends on a specific factor. (e.g. acid rain: a wide range of possibilities to measure the impact; salinity on the atmosphere)

Pollution indicators

• Biological Oxygen Demand (BOD): amount of dissolved oxygen required to break down the organic material in a water volume through anaerobic or aerobic activity
• Indicator species (biotic index 1-10) through invertebrates

Three-level model of pollution management.
replace, regulate and restore
Waste management

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.

Human Populations Around The World

As we have talked before, the resources of Earth are unequally shared between the organisms of human population. Of course all of these is influenced by the three spheres (social, economical and environmental)

Human Development Index

Adopted by the UN Development Programme as a measure of the well-being of a country.

Combines measurements of:

• Education
• Life expectance
• Standards of living
• Income
• GDP per capita (Gross Domestic Product)

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Countries might also classified based on their industrial development and GDP

MEDCs (used by modern geographers to specifically describe the status of the countries referred to: more economically developed)

• industrialized nations
• rich population small poverty
• high level of resource use per capita
• relatively low population growth rates

LEDCs  (less economically developed)

• less industrialized 
• natural capital unprocessed
• lower GDP and poverty rates
• Large population sector with low standard of living
• High population growth rates

Sustainable Yield in Deserts

Sustainability a wide spread term in the last decades. Economists, politicians, scientists and  businessmen are using it for everything. It is really a fashion nowadays. We must understand its real value and its real importance. A sustainable development is needed if we want to maintain the equilibrium of the world, respecting its carrying capacity. 
Sustainable yield is the the natural income that can be exploited each year without getting rid of the resources. Sustainable yield is different from one ecosystem to another. We’ll work with sustainable yield in deserts.
Specifications.
We must considered that resources in desert biomes are very scarce. The levels of precipitation are less than 15 cm a year. The diversity of desert’s flora is relatively low compared to other biomes. Contrary to the common belief the actual fauna of deserts is very rich and its concentrated in certain areas. The resources of deserts around the world differ from one and other. We can find oil and other fossil fuels in some deserts, minerals, and species richness.
In order to measure, and thus manage sustainable yield, we must establish space and time parameters. This will help us to know how much we have and how much we can use.
Useful indicators had been developed in order to maintain track of the advances in sustainable development. Some examples of this indicators can be found here, the Finland's sustainable development indicators:

• Human Development Index
• Greenhouse gas emissions
• Total energy consumption
• Use of renewable energy sources
• Energy and natural resource consumption in relation to economic growth
• Environmental loading in ration to economic growth

It is important to notice that not just because we are respecting the maximum sustainable yield (MSY) of a certain system, the resources will be endless. There are a lot of variations and factors that affect a system. A pretty good example of this is the chaotic situation of West Coast groundfish fishery in the United States, explained deeply here.
This is another thing in which indicators come handy and it’s the point where the management enters into the picture.
Links.
http://www.csgc.ucsd.edu/NEWSROOM/NEWSRELEASES/Carmel_Finley.html
http://www.ymparisto.fi/download.asp?contentid=92350&lan=en

Defining Sustainability

In simple words: sustainability is to endure. To exist for a long period of time. If you ask me, sustainability is “the responsible manage of resources that work towards using them while maintaining an equilibrium.”

Introduced in an actual context.
Sustainability is a term that has gained importance in the social world’s context because the arise of concern about the actual Eath’s natural capacity to sustain human life as it is know. That’s why the concept, in means of development, has been defined as: “sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.”

As a social issue, sustainability enters in means of maintaining the resources for future generation. We must understand that for the world natural equilibrium to be maintained, we need to start taking greater conscience about damage we are making to the environment and how we are wearing down its sustainability. That’s why society and specific institutions are working to create policies for the regulation of the human activities that act against sustainability.

In an economic context. The concept of sustainable yield enters into the picture. It is the increase of natural capital. The natural income that can be exploited each year without getting rid of it. MSY (maximum sustainable yield) is based on this last idea.

It’s equal to
-(The total biomass or energy at a time) T1 – (total biomass of energy at a time) T
-Annual growth and recruitment – annual death and emigration.

A few points to achieving a sustainable way of living:

• To control the exploitation of natural resources.
  
• To look for alternative practices that help prevent a loss of equilibrium.
  
• Understand the entire human society structure and the economic system as part of the global environmental system

Sustainability is involved in three different spheres. Each one of the spheres functions as an individual particle, but at the same time are affected by the others.