Feeding Humans By: Emma Robinson & Larissa Thorne

Table of Contents  Productivity and How it is important to Humans  Which ecosystem is best for productivity?  Factors that influence productivity in certain regions  The advantage of eating organisms at the bottom of the food chain  Biological Magnification  The Use Of DDT  Challenged caused by growth of human population  News Article  Questions

Productivity and How it is important to Humans  Productivity: The rate of biomass in an ecosystem.  Biomass: The amount of living matter in a given habitat.  Productivity is important to humans because the human population is very large so therefore we need a lot of food for everyone to stay healthy.  If there isn’t enough productivity it can and will cause malnutrition.

Which ecosystem is best for productivity?  The rainforest offers the best productivity because it has the highest rate of biomass.  The climate in the rainforest is very humid and hot due to the fact it is mostly found by the equator and the ocean.  Ecosystems that get a lot of sunlight and precipitation are also good for productivity.

Factors that influence productivity in certain regions  Warm and wet climates have the greatest amount of plant biomass because they have the best conditions in which photosynthesis can occur, which results in the highest productivity.  Things that influence plant growth: ~Temperature ~Moisture/precipitation ~Sunlight

The advantage of eating organisms at the bottom of the food chain  Organisms at the bottom of the food chain have the most energy.  ex: blueberries  The beginning of the food chain is where the lest amount of energy is used.  As you move up the food chain the organisms gain less energy as they eat from higher up the food chain.  If an animal higher up on the food chain eats one that is lower it doesn’t receive all the energy that the animal originally had.  By humans eating from the bottom of the food chain it is most profitable for us because we get the most energy.

Biological Magnification  Biological Magnification: Is an increase in the concentration of a substance as you move up the food chain. Meaning it would slowly break down by the natural process or not at all.  DDT: Is a pesticide that is moderately toxic, color less, taste less and almost odor less. It was mainly used in agriculture but people world wide have relied on it to kill misquotes.  Persistence: Is the continued existence of a pesticide, this means it breaks down slowly into harmful particles and enters into the water and soil. Example: DDT

The Use of DDT  In the 1950’s and 60’s, when it was most commonly used, in the water in Long Island had a low concentration of DDT. The algae and bacteria in the water took in the poison, the fish ate the algae, and the bird ate the fish.  Each time a bird ate a fish the bird gains more of the poison in its system. The chemical gathered in the organisms fat and built up over time. This is an example of biological magnification.

Challenges caused by growth of human population  Human population: The worlds population is increasing so more food is needed each year. Food productivity isn’t increasing enough to keep up with the population growth.  The worlds food isn’t divided evenly, if it was their wouldn’t be enough food for everybody to be strong and healthy.  Over 1 million people do not have enough food and safe drinking water.

Malnutrition  Malnutrition leads to loss of productivity because people don’t get the food the need,they can’t accomplish the jobs they need to do.  7.5 million people still suffer from hunger.  Over nutrition leads to 35 million deaths per year. Not having the right balance diet is also a big factor in this.

DDT: Pesticide linked to Alzheimer's  A study published by JAMA neurology showed that DDT showed up fours times as much in Alzheimer's patients than in healthy people.  DDT was a very successful pesticide, and was used to control malaria and agriculture, but there were many question that rose about humans safety and health.  Researchers believe that this may increase your chance of getting Alzheimer's if you live in an area that has used DDT in the past.

True & False  Biomass Is the amount of matter in a living habitat – true or false  DDT is related to Alzheimer's – true or false

Multiple choice  Human population – a) 2 billion people don’t have good food and water B) 1 million people don’t have good food and water C) 1 billion people don’t have good food and water

Multiple choice  Persistence – a) is the continued existence of a pesticide b) Is the concentration of a pesticide c) The pesticide breaks down quickly and doesn’t enter the environment

Short answer  Why is productivity important to humans ?

 Productivity is important is humans because the humans population is growing and needs more food to survive. Its important to have high productivity.

Short answer  What is Biological Magnification?

 It is the increase in the concentration of a substance as you move up the food chain.

Long answer  Why is it beneficial for humans to eat from the bottom of the food chain?

 Its beneficial to eat from the bottom of the food chain because things from the bottom of the food chain have the most energy but it also loses the least. As you move up the food chain the organisms have less energy, so by eating from the bottom we receive the most energy.

Long answer  What is DDT and how has it been used?

 DDT is a pesticide that was used in agriculture and for the extermination of misquotes. DDT has a high persistence and is very harmful to the environment. It was most commonly used in the 1950’s and 60’s.