Chapter 3 The Growing Environment Flashcards
Define solar radiation?
It is the main source of heat and sunlight.
What affects solar radiation?
- closer to the equator = more solar radiation (less atmosphere and 90° angle)
- higher altitude = more solar radiation = anthocyanin and tannin synthesis = ticker skins
- slopes and aspect affect solar radiation
- composition of he soil (color) affect solar radiation
- proximity to water = solar radiation reflected
Define latitude
The position of a region relative to the earth’s parallel and horizontal lines.
Latitude affects temperature and sunlight.
How does latitude affects solar radiation, and sunlight?
Higher latitudes = less solar radiation because of lower angles and more atmosphere but more sunlight hours during the GS.
Define altitude
The distance measured from sea level. Every 100 meters = 0.6°C
How does altitude affects weather?
At higher altitudes high diurnal range because = less air = less moisture = heat rapidly escapes = cooler nights.
High altitudes =rainfall Shadow
Define diurnal range
The average difference between day and night the temperatures.
How does diurnal range affects the grapes?
Diurnal range in warm or hot climates = cool period during night can slow down respiration of malic acid, and be beneficial for the formation of anthocyanins.
Define aspect
The direction to where a particular vineyard faces towards.
Explain the effects of aspect
The importance of aspect increases with altitude. Better aspect in cool climates = better exposure to sun.
In hot climates, worst exposure limits sun and heat = acid retention and less alcohol.
Slopes facing east heat up early in the morning = more hours of sunlight + dry the dew and less fungal disease.
Define Stomata
Pores located on the underside of vine leaves.
Explain how stomata works?
- Water vapor diffuses out
- CO2 out & O2 in = photosynthesis
- open and closes depending on the availability of water
- Allow transpiration and other essential plant regulations.
Define evapotranspiration rate
The amount of transpiration from the vine + the evaporation from the soil surface. The speed at which water is no longer available.
Higher evapotranspiration = More water is needed to satisfy the vine needs.
What affects evapotranspiration?
Depends on temperature, humidity and wind.
What are the more important nutrients for the plant?
Nitrogen - N
Potassium - K
Phosphorus - P
Calcium - Ca
Magnesium - Mg
Effects of Nitrogen N
- Component of proteins and chlorophyll.
- To much N = excessive vegetative growth and low rate of ripening + poor ventilation.
- Too little N = reduced vigor and yellow leaves.
- Low levels of nitrogen = grapes problematic for fermentation.
- Vines with low level of N produce better quality grapes.
Effects of Potassium K
- Very high levels of K can cause problem in the uptake of magnesium = reduce yield and poor ripening.
- High levels of K = high levels of K in grapes + high acid in the must
- Low levels of K = low sugar accumulation, reduced yields and poor vine growth
Effects of Phosphorus P
- Important for photosynthesis
- Too little P leads to poorly developed root system = poor water and nutrients absorption, reduced vine growth and low yields
Effects of Calcium Ca
- Has a role in the structure of plant cells & photosynthesis.
- Low Ca has a negative impact on fruit set.
Effects of Magnesium Mg
- Mg is found in chlorophyll and is important for photosynthesis
- Low Mg leads to low yields and poor ripening.
Define soil texture
The proportion of the minerals of sand, silt and clay + rock fragments: gravel and pebbles
How does soil texture affect?
Texture of soil
Define soil structure
How the mineral particles in the soil aggregates. The size, shape and stability of the soil determine water drainage, root growth and workability of the soil.