Food Resources

* there is enough food in the world but there is an imbalance in its distribution * terrestrial and aquatic food systems have different efficiencies * different food production systems make different demands on the environment * food production is closely linked with culture, tradition and politics * subsistence and commercial farming manage soil in different ways.

Undernourishment leads to retardation and social and developmental disorders
Malnourishment is when food contains enough energy but lacks nutrients like vitamins, minerals and protein.
In most MEDC’s food is cheap
In LEDC’s people struggle to produce enough food to sustain them.

Distribution is one of the main causes of lack of food for some coutnries.
Politically, it affects the world food supply
There are differences in the amount of calories that each country consumes
The composition of food also differs in MEDC’s and LEDC’s. (more meat in MEDC’s and cereal in LEDC’s)
So far the food supply has kept up with our needs

Subsistence farming is when farmers practice farming for their families or their own small communities not to gain profit. Commercial farming is profit based farming or ‘cash farming’. Extensive farming uses more land with a lower density of planting and lower inputs and outputs Intensive farming uses land more intensively with greater inputs and outputs. Pastoral farming is the raising of animals Arable farming is sowing crops on good land to feed the animals. Mixed farming has both crops and animals and it’s a system where the animals waste is used to fertilize the crops and some of the crops are used to feed the animals.

The energy budget of can be calculated by either the product per unit area
The energy it took to produce that food, and deliver it to the market
Remember that the quality of energy is different in each type of food (proteins, carbs..) Therefore to equate measures grain equivalent in kg is used * read rice production in Borneo and Cal page 252-253

fish industries
70 percent of the world industries are fully exploited demand is increasing but fisherman are having trouble finding fish
“tragedy of the commons” is when something isn’t owned by anyone it is not taken care of and is exploited because no one feels responsible to take care of it.

Maximum sustainable yield (MSY)
Sustainable yield is the increase in natural capital, that can be exploited each year without depleting the original stock or its potential for replenishment.
Maximum sustainable yield is the highest amount that can be taken without permanently depleting the original stock.
The carrying capacity for each species depends on their reproductive strategy.

SY= (total biomass or energy at time t+1) – (total biomass or energy at time t)
SY – annual growth and recruitment – annual growth and emigration

A safer approach is called optimal sustainable yield (OSY) this is calculated as half of the carrying capacity.

Terrestial and aquatic food production systems compared
In terrestrial systems, food is harvested at first or second trophic level- meaning that they are making efficient use of solar energy.
In aquatic systems, food comes from higher trophic levels- therefore energy efficiency is less Even though energy conversions are generally more efficient in oceans, the fourth trophic level is still less than first

Future global food supply
Feeding the future is a challenge- population is growing and available area for agriculture is decreasing. Erosion, desertification, eutrophication and salinization
Another way to increase amount of food is improving storage and distribution methods. This will lead to smaller losses and more efficiency Also changing people’s diets can help
-genetic engineering mixed cropping and interlpanting pest management new crops being developed irrigation control fish farming improve crop storage and reduce spoilage less food processing so less energy is spend on transport and packaging education about food so we don’t take too much or too little- distribution + diet