**C5 Food Shortage**
### Physical factor
1. **Climate**
- solar energy
- Temp (growing season, frost free period, frozen soil)
- Precipitation (e ective precipitation)
1. **Relief**
- Altitude (snow line)
- Aspect
- Gradient
1. **Water**
1. **Soil**
- optimal pH of soil
- Thick soil
### Cultural factor
**Economy**
1. Technology
2. Capital
3. Labour
4. Government
5. Transport
**Agricultural characteristics**
1. Subsistence / commercial
2. Arable / pastoral / mixed
3. Intensive / extensive
4. Sedentary / shifting
### Physical input
1. **Climate (Mediterranean climate)**
*Western coast*
- Cool in both summer and winter
- Above 10 in winter and above 15 in summer, high evaporation
- Small annual range of temperature (California current, cold current in summer)
- Warm onshore wind in winter
- Eg San Diego annual range 8.5
- Low annual rainfall (200-500)
- High pressure (subtropical high pressure belt and cold current)
- Humid winter with warm wet onshore wind, some storms form from the Golf of Alaska Inland
region
- arid to semi arid climate
- Hot summer cool to cold winter
- Above 5 in winter above 25 in summer
- Frost may occur, cold air mass moving into California from the continental N of US frozen soil
- Large annual range of temperature, without maritime in uence
- Eg Brawley annual range to temp 20
- Low annual rainfall less than 500, many areas less than 200
- Dry o shore wind, rain shadow region eg Central Valley blocked by coastal ranges
ff ff fl
, 1. **Relief**
- rugged relief lack of atland eg Sierra Nevada, coastal ranges except Central Valley, imperial
valley and western coast
1. **River**
- San Joaquin River and Sacramento River for Central Valley(from all snow melt of Sierra Nevada)
- Colorado River for Imperial Valley
1. **Soil**
*Alkaline soil*
- Evapotranspiration rate > precipitation
- Capillary action
- Evaporation of water
- Salt crust
- Salinization
- Alkaline soil
*Infertile soil*
- sparse vegetation, woodland and shrubs at N, grassland and desert at S
- Low humus and nutrient supply
- Low soil water storage capacity
- Soil erosion by wind and water
1. **Pest and disease**
*Cultural input*
1. Technology to overcome constrains
2. Capital intensive
3. Labour shortage due to urbanization, input labour from Mexico
4. Stable political condition (California Department of Food and Agriculture of the State
Government)
5. Education
6. Transportation for local and overseas markets eg Southern California freeways, Chino Valley
Freeway, Los Angeles International Airport, San Diego International Airport
### Agro-chemicals (fertilizers)
**Positive**
- More nutrients to the soil to replace leaching, runo and crop absorption
- Quality and quantity increase
- Economic e ciency increase
**Negative**
- high cost of chemicals
- Increase output lower the market price
- Law of diminishing return, rst increase till the optimal, then decrease when overuse: 1. crop
lack response 2. More pest and disease 3. Change in soil acidity
- Water pollution
- Eutrophication, algae bloom, red tide
- Soil toxi cation
- Nitrogen fertilizer cause global warming
### Insecticides
fi ffi fl fi ff
### Physical factor
1. **Climate**
- solar energy
- Temp (growing season, frost free period, frozen soil)
- Precipitation (e ective precipitation)
1. **Relief**
- Altitude (snow line)
- Aspect
- Gradient
1. **Water**
1. **Soil**
- optimal pH of soil
- Thick soil
### Cultural factor
**Economy**
1. Technology
2. Capital
3. Labour
4. Government
5. Transport
**Agricultural characteristics**
1. Subsistence / commercial
2. Arable / pastoral / mixed
3. Intensive / extensive
4. Sedentary / shifting
### Physical input
1. **Climate (Mediterranean climate)**
*Western coast*
- Cool in both summer and winter
- Above 10 in winter and above 15 in summer, high evaporation
- Small annual range of temperature (California current, cold current in summer)
- Warm onshore wind in winter
- Eg San Diego annual range 8.5
- Low annual rainfall (200-500)
- High pressure (subtropical high pressure belt and cold current)
- Humid winter with warm wet onshore wind, some storms form from the Golf of Alaska Inland
region
- arid to semi arid climate
- Hot summer cool to cold winter
- Above 5 in winter above 25 in summer
- Frost may occur, cold air mass moving into California from the continental N of US frozen soil
- Large annual range of temperature, without maritime in uence
- Eg Brawley annual range to temp 20
- Low annual rainfall less than 500, many areas less than 200
- Dry o shore wind, rain shadow region eg Central Valley blocked by coastal ranges
ff ff fl
, 1. **Relief**
- rugged relief lack of atland eg Sierra Nevada, coastal ranges except Central Valley, imperial
valley and western coast
1. **River**
- San Joaquin River and Sacramento River for Central Valley(from all snow melt of Sierra Nevada)
- Colorado River for Imperial Valley
1. **Soil**
*Alkaline soil*
- Evapotranspiration rate > precipitation
- Capillary action
- Evaporation of water
- Salt crust
- Salinization
- Alkaline soil
*Infertile soil*
- sparse vegetation, woodland and shrubs at N, grassland and desert at S
- Low humus and nutrient supply
- Low soil water storage capacity
- Soil erosion by wind and water
1. **Pest and disease**
*Cultural input*
1. Technology to overcome constrains
2. Capital intensive
3. Labour shortage due to urbanization, input labour from Mexico
4. Stable political condition (California Department of Food and Agriculture of the State
Government)
5. Education
6. Transportation for local and overseas markets eg Southern California freeways, Chino Valley
Freeway, Los Angeles International Airport, San Diego International Airport
### Agro-chemicals (fertilizers)
**Positive**
- More nutrients to the soil to replace leaching, runo and crop absorption
- Quality and quantity increase
- Economic e ciency increase
**Negative**
- high cost of chemicals
- Increase output lower the market price
- Law of diminishing return, rst increase till the optimal, then decrease when overuse: 1. crop
lack response 2. More pest and disease 3. Change in soil acidity
- Water pollution
- Eutrophication, algae bloom, red tide
- Soil toxi cation
- Nitrogen fertilizer cause global warming
### Insecticides
fi ffi fl fi ff
