Climate and Soils

1
Climate and Soils
2
Climate

• Climate
• Definition, weather over a long period,
  weatherclimate of today.

3
Factors Associated with Climate

• Temperature, min, max, average
• Rainfall, precipitation, amount, distribution
• Light, especially day length
• Relative humidity

4
Various Climate Categories

• Zonal
• (10 major zones in North America based on min
  temp )
• Example -50 to -35 zone 1, Florida 20-30zone
  10

5
Various Climate Categories

• Koppen system, 5 divisions, temp precipitation
  (handout 1)
• Boreal, temperate, subtropical, tropical

6
Tropics Bounded by 23.5º N-S Lat. (geographical)

• Tropic of Cancer- north, Havana, Cuba
• Tropical of Capricorn- south, Sao Paulo, Brazil

7
Characteristics of Tropical Areas (temp. day
length)

• Average temperature gt18º C
• Absence of frost- except highest elevations
• Day length is constant - varies 7 min/degree
• Very little variation diurnally in temperature

8
Characteristics of Tropical Areas (rainfall)

• Average rainfall varies 750-4300 mm/yr
• Tropics can be always wet
• Have wet-dry seasons
• Dry

9
Characteristics of Tropical Areas(altitudinal
changes)

• Hot zone- 0-1000 m, low tropics
• Temperate zone- 1000-2000m, mid tropics
• Cool zone-gt2000m, frost occurs at 4000m, high
  tropics
• Temperature changes 5ºC/1000 m elevation

10
Division of Tropical Fruits Related to
Temperature (handout 2)

• Temperature dictates range of tropical-subtropical
  fruits, especially minimum temperature
• Tropical range will not tolerate freezing. These
  include
• Durian, mangosteen, cacao, cashew

11
Division of Tropical Fruits

• Subtropical origins (some tolerance) via
  supercooling
• Mango (-2ºC), not -16
• Litchi (-2ºC)
• Avocado (depends on race)
• 1. West Indian (1.5ºC)
• 2. Mexican (-4 to -5ºC)
• 3. Guatemalan (-2ºC)

12
Division of Tropical Fruits

• Truly subtropical
• Tahiti lime (-4 to -5ºC), citrus to- 7ºC
• Olive (-7 to -12 ºC)
• c. Pistachio (-12 ºC)

13
Division of Tropical Fruits

• Temperature Averages
• Temperature ranges above freezing are also
  important for optimum growth and productivity
  Poor growth lt 10 C
• Also chilling injury to fruit

14
Subtropical Fruits(usually located 23.5 -40
NS latitude)

• Average Temperature lt18º C, with one month lt18ºC
  and 8 months gt10ºC
• Frosts or freezes occur
• Large diurnal temperature fluctuations
• Large fluctuations in day length

15
Subtropical Fruits(usually located 23.5 -40
NS latitude)

• Humid subtropics-Florida, Brazil
• Arid subtropics-Mediterranean type climates,
  Spain, California, South Africa, Australia, Israel

16
Soils (see soils map pg 13)
General Soil Properties
Major Soil Series (Types vary throughout tropics)
17
General Soil Properties

• Drainage
• Water holding capacity
• Nutrient holding capacity
• pH
• Organic matter content

18
Major Soil Series(Types Vary Throughout Tropics)

• Oxisols - Highest weathered, leached, red and
  yellow, dry
• Aridisols - Highly weathered, leached, red and
  yellow, dry
• Alfisols - clay and nutrient rich subsoil

19
Major Soil Series(Types Vary Throughout Tropics)

• Ultisols- clay enriched subsoil, low in nutrients
• Vertisols - formed from volcanic ash

20
Other Important Soil Series

• Spodosols- acidic sands with a hardpan
• Entisols- acidic sands
• Mollisols- dark surface horizon, nutrient rich

21
Other Important Soil Series

• Inceptisols- retain some weathered minerals
• Andisols- formed from volcanic ash

22
Soils in Dade County Tropical Fruit Area

• Classified as Krome, very gravely loam
• Or as Chekika very gravely loam, very rocky
• Soil series( order) Entisols

23
Soils in Dade County Tropical Fruit Area

• Very rocky, porous
• High pH, 8.0- 8.5
• Minor element deficiencies
• High water table