Eutrophication

Too many nutrients, algae grows, there is no light, plants die, there is oxygen depletion

The primary causes for eutrophication are anthropogenic Detergents and fertilizer
However there is the case of natural causes.
Eutrophication will cause at the end the dead of many organisms in the body water, most of the times because the lack of oxygen.
This phenomena is specially harmful in slow moving water bodies.

How do we stop it?

• Controlling the runoff from crop fields and from urban areas
• Control the amount of fertilizers used in agricultural practices
• Develop buffer zones around body water. Growing plants around them. The plants will absorb the excess of nutrients
• Set water treatments on sewage sources.
• Oxygenize the water
• Drench the sediment off the water.

Indicator Species

Aquatic ecosystems
Oyster: They fed on organic material and pollutants in the water. They filter the water, removing the particles.
Vertebrate and invertebrate species: Found in rivers and streams. Can determine the grange pollution to kept in check.
Lilies: rivers, lakes, ponds and swamps. They absorb oxygen and sunlight. Indicate abundance of nutrients, which leads to eutrophication.

Mayfly larvae: Native specie that are adapted to live in certain biome. When its number decreases it is a very clear sign that the pollution levels are increasing. They reappear downstream as the effects of the discharge are diluted. This help to indicate the level of pollution in water.
Sludge Worm. Common in lakes and rivers. All fresh water ecosystems. They fed on the sediments and bacteria, hence a great population on them might indicate great pollution in the body water and oxygen-poor water. They indicate stagnant water unfit to drink.
Soil Indicator species
The plants that are found in certain soil might indicate the presence or absence of a specific substance.
Besides plants, there are many other indicators.
Birds eggs can be analyze to find out pesticide sin the soil.
Invertebrates:. Indicator species to identify the use of foreign soils, insecticides, pesticides, and other pollutants.
In Canada there are plans to use soil-living arthropods in order to quantify the pollution in the forests.
A good way to measure the healthiness of an ecosystem and to determine the presence of pollution is biodiversity. High biodiversity indicates a strong and healthy environment.

  .

Population Policies in Australia and Russia for sustainable development

Australia: Sustainable Population Strategy

-          The objective:

Improve the well-being through management of population change’s impacts.

The thing is not to stop the growth, but address the issues that it generates in an adequate way.

Seeks to identify and take action in areas where population change may lead to unsustainable environment and natural resource management practices.

-          How it is supposed to address the issues:

Carefully planned, sustainable management of this natural capital is essential to ensure it remains healthy and available to current and future generations

-          How do the policies will affect population growth?

•         The Sustainable Population Strategy will considered, and thus, affect directly aspects of population dynamics such as fertility, life expectancy, internal movements, and migration levels.

•          It will intend to look after the condition of different growth rates and conditions for different areas of the Australian territory.

•          It will work with the National Urban Policy that will make able to maintain the urban population, which represents almost the 80%, by addressing and controlling issues, such as: water scarcity, service delivery, food security and health services.

•          The research for the strategy has given out results that show that the increase of Australian food production in the last decades are due to an increase in efficiency and productivity, rather than the disposition of more agricultural land. The strategy intends to exploit productivity in order to handle the increasement of population.

•          Carbon dioxide emissions will be lowered as the strategy plans a reduction in the pollution per capita. This will lead to greener practices among the population, better living standards and the move towards sustainable power sources.

•          The country establishes a great importance in the population growth due to the need of work force.

•          Migration is an important factor to consider as it represents skilled workforce, innovation, a dynamic society with different views, connection with other nations, and foreign capital in the Australian economy.

The Strategy would set three different independent panels to look at population change through different lenses:

1. Demography and liveability
2.  Productivity and prosperity
3.  Sustainable development

Russia policies of population strategy

In recent years Russia’s government, led by President Vladimir Putin, has established new population and sustainable development policies that are intend to response to the issues that the country is facing. A shortening population, lack of workers

Russian government feels that the worst problem is the issue is the population crisis of implosion. The government has decided to implement policies that will increase the birth and fertility rate of the country by trying to increase the number of children per family.

A repatriation program has been set by the government in order to bring back the former Russians that have left the country looking for specialized opportunities aboard. The program includes monetary incentives, social benefits and employment opportunities.

There is a proposal to change he immigration policies in order to make them friendlier with foreigners, increasing the appeal of the country to skilled and non-skilled outsiders.

Russia is the second nation that receives more immigrants, being USA the first one.  A great part of these immigrants are illegal. Illegal immigrants are subject to bad job possibilities and don’t contribute the activation of the economy. New migration policy will control the access of illegal immigrants and will concede legal registration and working permit to the greater part of the illegal immigrants that are already in Russia. The law defines quotas for migrant sending countries and high penalties for employers who illegally employ migrants.

References

1. Hibbard, Courtney. "Russia's Population Plan - San Diego Public Policy | Examiner.com."Washington DC News, Washington DC Information, Washington DC Events - Examiner.com | Examiner.com. 30 Apr. 2009. Web. 11 Jan. 2011. <http://www.examiner.com/public-policy-in-san-diego/russia-s-population-plan>

2. Banjanovic, Adisa. "Russias New Immigration Policy Will Boost the Population Euromonitor Archive." Market Research for Industries, Market Research for Countries, Market Research on Consumers. 14 June 2007. Web. 11 Jan. 2011. <http://www.euromonitor.com/Russias_new_immigration_policy_will_boost_the_population>.

3. Commonwealth of Australia. "A Sustainable Population Strategy for Australia - Issues Paper - online version."Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC) - Home Page. N.p., n.d. Web. 11 Jan. 2011. <http://environment.gov.au/sustainability/population/publications/issues-paper2.html>.

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.

---

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.

---

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

---

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.

---

*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.

---

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.

---

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

---

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.

---

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

---

Crude Death Rate (CDR)

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

Number of deaths x 1000

population size

---

Natural Increase Rate

NIR = (CBR - CDR) / 10

Doesn’t consider immigration and emigration.

---

Doubling time

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

Doubling time = 70 / NIR

---

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

---

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.

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)

---

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

Human Population Dynamics

A very interesting topic. How much does the human population can reach? Which is our carrying capacity?

Different opinions were shared in class. Some said that we had already past our carrying capacity for more than 4 billion organisms. Others said that we are reaching it already. The odd thing was that non of us though we have too much time before we reached our carrying capacity (K)

We have to take into account that in contrast to the other species, we have created a very complex economic system that maintains our society in order and measures the “power” of each entity. This directly affect the dynamics of the our population by stating the repartition of resources and define relationship between entities.

In order to establish an equal share of resources for each organism the population would have to decrease. This is because , even if the global economic system changes its standards, there isn’t enough resources to maintain the actual 6 billion human population.

A simulation of the human population dynamics can be found in this webpage www.breathingearth.net It’s pretty interesting.

Matter keeps rolling...

Inside the ECOSYSTEMS we find some cool features. Now we'll work with each of the elements that form them.

Living organisms are presented in every ecosystem. They have seven main characteristics:

1. They have/are cells

2. They reproduce

3. Grow and develop (die)

4. Absorb and use energy and materials

5. Maintain homeostasis

6. Respond stimuli

7. They're organized

There are thousands and thousands of organisms around the world. They're classified with different schemes or keys.

Organisms within an ecosystem can be recognized as producers, consumers, and decomposers by the way they obtain matter and energy. This division brings on the trophic levels.

Energy and matter flows through these trophic levels. As it had been told, energy is not completely transfered between levels 'cause some of it is used by each organisms.

Each organism found within an ecosystem is called an individual. Individuals that share similar characteristics and can reproduce between them form can be identify as a specie. A group of organisms of the same specie form and population. When populations are found together in a given area and interact between them they form a community.