Extra-curricula Flashcards
What are the 3 key practices to express terroir in wines?
- Timing of phenology
- Water deficit
- Moderate to low Nitrogen
Source: Presentation ‘Interactions of climate, soil and grapevines on wine and terroir’ by Kees van Leeuwen, professor of viticulture at Bordeaux Sciences Agro, and Bordeaux University’s Institut des Sciences de la Vigne et du Vin
Why is timing of phenology important in producing quality fruit (and thus in expressing terroir)?
To achieve high terroir expression, precocity of the grape varieties should match the local climatic conditions, so as to obtain full ripeness at (not before) the end of the season: 10SEP-10OCT in the Northern Hemisphere.
Grapes should not ripen early in the season, because quick fruit ripening in warm conditions limits aroma synthesis.
Grapes that would not attain full ripeness are too acidic, with low sugar and little aroma development.
Why is a water deficit important in producing quality fruit (and thus in expressing terroir)?
Water deficit results in higher quality fruit, because it induces:
- Early shoot growth cessation
- Reduced berry size
- Lower malic acid
- Higher Anthocyanins
Why is moderate to low nitrogen important in producing quality fruit (and thus in expressing terroir)?
Moderate to low nitrogen results in higher quality fruit as a result of:
- Lower vigour, yield and especially berry weight
- Lower acidity
- Higher sugar and Anthocyanins
What is climate?
The annual weather pattern of an area averaged over several decades
Why do they use Chardonnay and Pinot Noir in some continental regions
- They are early-ripening varieties
- In Champagne, Northern regions of Germany and British Columbia there’s long day length but temperatures drop more rapidly in autumn
- => shorter growing season
- => less sunlight and warmth available to the vine at the end of the growing season.
How many Growing Degree Days (GDD) in Amerine Winkler Category I
Below 1370
what is the effect of temperature on photosynthesis?
In cool temperatures, the rate of photosynthesis slows.
What is soil profile
Reveals the different structural and textural soil types
Reveals the depth of the layers
Reveals if there are any drainage or root barriers in the soil
The best fruit comes from
Densely planted, small vines growing on infertile soils.
At what temperature is wine dormant
Below 10 C
When is the growing season in the northern hemisphere?
April to October?
What is Granite
Igneous rock, formed from magma. extremely hard and dense but still free draining.
When is a climate continental?
large difference between the average mean temperature of the hottest month and the coldest month.
explain photosynthesis
Sunlight
H2O Glucose
Chlorophyl Sucrose
CO2 Fructose
Vines grow best on soils with ______________ fertility.
low
What is Aspect
- the direction a vineyard slope faces
- an important charerteristic of a vineyard site where more or less exposure to sun is required
Explain freeze injury to dormant vinifera wood :
- begins at -15°C
- serious at -20°C
- can be fatal at -25°C
unless the vine is insulated by snow or earth pushed up around the vine
EU zone B : What is the acid adjustment (tartaric)?
-1 to + 2,5 g / L
Aeration is affected by
Capacity of the soil to drain effectively.
Canopy climate is called
Microclimate
Temperature _____________ with every 100 meter rise above sea level (altitude–.
Decreases by 0.6 degrees Celsius
What pH grape vines cant tolerate, why
pH bellow 5, aluminium becomes available which poisones the plant.
What are the advantages of sandy or gravelly soils?
- have very good drainage, lower water-retaining capacity
- encourage a vine to grow longer roots which search for water
- benefit from more consistent water levels
- warm up more quickly in spring
- are generally warmer than clay soils
Name some typical moderate climate regions
Bordeaux, N. Rhone, Rioja, Piemonte, Toscana, Coonawarra,, moderate parts of Napa and Sonoma.
Name some soil Micronutrients
Boron
Manganese
Copper
Iron
Molybdenum
Zinc
Cobalt
Chlorine
Silicon
EU zone CII : enrichment may not rise the total alcohol to more than?
13 %
Why are isolated hills ideal vineyard site?
Name 2 renowned hills
- there are no big currents of colder air flowing down from the main hills.
- Burgundy’s hill of Corton (Aloxe-Corton), Montagne de Reims (Champagne)
Limestone rich soil tends to have high pH which inhibits the uptake of iron and other micronutrients and can increase the risk of what
Chlorosis
EU zone A : What is the acid adjustment (tartaric)?
-1 to 0g / L
What is the average mean temperature during the growing season for hot climate?
over 21 °C
What is sulfur?
- S
- macronutrient
- Essential constituent of some amino acids and enzymes.
How can you produce quality fruit in fertile soils?
dividing the fertility between a larger number of shoots
create bigger vines
lower density planting
EU zone C : What is the amount of natural alcohol?
9 %
What regions are in EU region B
Baden, Loire, Champagne, Alsace, Austria, parts of Romania, most Czech Republic
What regions are in EU region C 1b
Hungary, Trentino-Alto Adige
Regions with Granite soil
Baden
Northern Rhone
Grapevines cannot tolerate soil pH below
why?
- 5
- alluminium becomes available to the plant
- it poisons the plant
What is good soil structure?
- It is where the particles form stable crumbs of 1 - 5mm in diameter.
- there must be high to moderate organic matter content (3 - 10 %)
Regions with Limestone soil
Central & eastern Loire
Piedmont
Northern Spain
Burgundy
Limestone Coast in S Australia
Organic content is formed from
Animal remains broken down by beetles, mites, earthworms, fungi and bacteria
What is lighter soil?
- high sand or gravel content
- more free draining
Name some typical warm climate regions
South Rhone, Douro,, McLaren Vale, Paarl
Maritime climate is ideal for what kind of wines? Give also examples.
medium-bodied wines with moderate alcohol levels e.g. red and white Bordeaux, Muscadet, Rias Baixas, Vinho Verde and South of England.
What is the danger of soil compaction?
- can lead to poor rain infiltration
- reduced drainage, aeration, root penetration
At what temperature is optimal vine growth
22-25 C
What kind of wines and what region are best in Amerine Winkler Category II
Premium medium bodied red wines. Regions include Napa Valley, Bordeaux, North Rhone.
What type of wines are often produced in warm climate?
Often fortified wines such as Port of Liqueur Muscat
How can the close proximity of forests be disadvantageous?
- they cool the mesoclimate in warm weather and increase humidity
- they can harbour large flocks of birds which feed on and damage grapes
EU zone C : What is the acid adjustment (tartaric)?
-1 to + 2,5 g / L
zone CIIIb => 0 to + 2,5 g / L
What is Loam
Balanced mixture of clay, silt, and sand. Combine nutrient holding abilities of clay with good drainage capabilities of sand.
Soil fertility (its chemical and physical characteristics) is influenced by
- Soil texture
- Soil structure
- Organic matter content
- Mineral content
- Availability of air and water
- Level of acidity/alkalinity
How many Growing Degree Days (GDD) in Amerine Winkler Category III
1650-1930
Name some typical hot climate regions
San Joaquin Valley.
What increases equally with the vine’s metabolism?
Its demand for sugars.
Why do vines not grow well on poorly drained soils?
- they are cooler
- they take longer to heat up in spring
- they can restrict root growth
- leading to reduced resistance to drought
- increased risk to mineral deficiency
- reduce the bearing capacity of a soil causing problems when machinery passes
What is the photoperiod?
daylenght
Used to improve soil structure, reduce dispersion of surface soil, minimizes swelling of sub-surface soils, thus improving permeability and aeration
Gypsum (CaSO4)
EU zone B : What is the acid adjustment (tartaric)?
-1 to 0g / L
What is the advantage of an eastern aspect?
- When a vineyard faces the rising sun, the sun’s rays are scattered less in the morning, when the earth has cooled overnight and the dust has settled.
- Many of the best vineyard sites face east.
Which ocean currents create cooling mists and fogs and cool down temperatures?
Pacific Ocean current (Calif.) Humboldt Current (Chile--
Vines grow best on soils with low fertility. Why?
- Restrict canopy growth
- Are stony and well drained
When is a site considered unsuitable for vine culture qua min. temperature?
- if its temperature falls below -20°C more than once every 20 years
- if the mean temperature for the coldest month is less than -1°C
why does growths slow above 25 ° C?
The vines metabolic needs increase faster than its ability to photosynthesise sugars.
pH should be increased above 6.5 using what
Calcite (Calcium carbonate); Magnesite (Magnesium carbonate) or Dolomite (mix of both)
What allows the production of high quality wine in areas as California and Chili that would otherwise be too hot?
The Pacific Ocean current (CA– and the Humboldt Current (Chile–) create cooling mists and fogs and cool down temperatures
Organic content is composed of
Sugars
Starches
Cellulose
Nitrogenous compounds
Mineral matter
PH for neutral soil
pH of 7
Soil acidity is measured by the pH scale which measure what
concentration of hydrogen ions in the soil solution
Sandy soil in high rainfall area will be deficient in which nutrients
Potassium, Calcium, Sulfur
Can derogations be obtained from the EU-zone stipulations?
- under exeptional conditions
- e.g. enrichment of up to 4,5% abv is permitted in zone A in particularly poor years
Maritime climate is charachterised by :
(temperpature, rainfall, grape berry ripening period)
- low anual range of temperature (warm summers, mild winters)
- relativaly high rainfall
- => extra cloud cover
- reasonably long grape berry ripening period with moderate temperatures.
Why does the GDD-system work not work adequately in e.g. Australia?
- Because temperature variability, sunlight, humidity are less correlated with temperature then in California .
*
Why is sunlight essential to all plants?
- It is the energy source for photosynthesis
- It increases the temperature of the environment
What is the average mean temperature during the growing season for moderate climate?
16,5 to 18,5 °C
Regions with Chalk soil
Champagne
Jerez
When is a climate maritime?
small difference between the average mean temperature of the hottest month and the coldest month.
What is the disadvantage of a loam soil?
disadvantage : rich, loamy soils can encourage too much vegetative growth and shading of fruit.
Macroclimate can be classified according to : (2)
- Temperature
- continentality
What are wine styles for cool continental climates and give examples?
- intensely-flavoured, late-harvested white wines with high potential alcohols which may be vinified as sweet wines (vendage tardive in Alsace) of dry (Smaragd wines in Austria’s Wachau)
What is phosphorus?
- P
- macronutrient
- key element in Energy fixation encourages root growth and ripening.
What does the slope or incline of a vineyard influence?
- sunlight interception
- air movement
- soil properties
- cost of working the land
What is Shale
Originally composed of clay, quite soft.
Soil texture is influenced by
- Organic matter
- Earthworms
- Wetting and drying
- Freeing and thawing
- Plant roots
- Cultivation
- Drainage
- Compaction
How is heat summation calculated (Amerine and Winkler)
Measuring the mean temperature for the month, subtracting 10 C and multiplying by number of days in month. Monthly sum are totaled for each of seven months of growing season.
Continental climate is charachterised by :
(temperpature, rainfall, )
- wide anual range of temperature (hot summers, cold winters)
- drier than maritime climate
*
What is the advantage of the drier climate in continental regions over maritime regions?
Is reduces the risk of rot at the harvest time and makes later harvesting less of a risk.
Why can bodies of water near a vineyard be negative in a cooler climate?
- it increases the humidity of a site, which increases the risk of fungal disease, in particular downy mildew.
What is the most commonly used climate indice?
Amerine and Winkler’s heat summation system (1944)
What does soil structure affect?
- the availability of water and air to plants
- the ability of fine feeding roots to penetrate the soil and exploit rhe essential plant nutrient supply
EU zone CIII : enrichment may not rise the total alcohol to more than?
13,5 %
What is the advantage of regions in a high lattitude?
They have a greater capacity to photosynthesise due to increased daylenght in the summer.
What are the major soil types associated with viticulture :
- limestone
- chalk
- slate
- granite
- volcanic rock
Why is altitude beneficial for hot climates?
- Vineyards can be planted at higher elevations in areas otherwise too hot for wine production
- it increases the cooling effect of wind exposure
A soil’s relative proportions of particle sizes affect
- Water holding capacity/availability
- Soil warmth
- Availability of nutrients
Name micronutrients in soil
Boron, Magnase, Copper, Iron, Molybdenum, Zinc, Cobalt, Chlorine, Silicon.
EU zone A : What is the amount of natural alcohol?
8 %
What is magnesium?
- Mg
- macronutrient
- Essential component of chlorophyll
- regulates internal acidity and sugar metabolism.
- Encourages ripening.
PH for alkaline soil
pH from 7.1 - 8.5
In hotter regions, a vine needs ______________ mm/year precipitation.
750
Temperature affects the quality of a winegrape crop by influencing :
- the level of yield obtained
- the accumulation of sugars and the reduction of acidity in the berry
- the development of wine aroma and their precursors
Effects of excess rain on yield and quality
- Cools the mesoclimate
- More difficult for machinery to work in the vineyard.
- Increased risk of fungal disease (mildew, grey rot, phomopsis)
- Reduced fruit set
- Bunch compaction or berry splitting prior to harvest
- Diluted flavors if it rains just before harvest
What are advantages of sloping vineyards? Where best valued?
- cold, relatively dense air moves downhil
- the sinking, cold air displaces warmer, less dense air to higher levels
- it produces warm thermal layers on the slope
- above the warm layers air temperature again drops
- best vineyards run along the middle band of the slope (e.g. Côte d’Or)
- especiallly valued in cool climates
- air movement deters frost
- offers slightly improved ripening petential
- the sinking, cold air displaces warmer, less dense air to higher levels
- soils on slopes tend to be poorer, more coarsely textured, better drained => moderates vine vigour
Temperature affects the yield of a vineyard directly by influencing :
- the rate of growth (vigour) of the vines
- the number of flower clusters produced and their size
- the succes of the setting of these flowers into berries
What grape varieties grow best in warm climate (18.5 -21 C average mean temp. during growing season)
Heat loving varieties (Grenache, Mourvedre, Ruby Cabernet ).
Benefits of humus
- Maintains soil structure
* it helps bind the particles - Retains nutrients
* it is slightly negatively charged, most soil nutrients are positively charged - High water holding capacity
- Small range of swelling and shrinking and cohesion
- Gradual release of nutrients
- humus is slowly mineralised
6. Dark color increases soil’s ability to absorb heat
What is “the slope” of a vineyard?
The incline of a vineyard.
What is “degree of continentality?
The difference between the average mean temperature of the hottest month and the coldest month.
What are grapes for warm continental climates and why?
- Malbec and Cabernet Sauvignon
- because of possibility of later harvest
What is potassium?
- K
- macronutrient
- Regulates water flow and sugar in the plant;
- encourages ripening.
What is nitrogen?
- N
- macronutrient
- component of many critical plant constituents (nucleic acids, animo acids, chlorophyll)
- drive biochemical reactions
- stimulate photosynthesis
- Second only to water in importance for plant growth.
Vitis vinifera requires ____________ hours of sunshine to produce ripe fruit.
1250 hours
What regions are in EU region A
Germany (excluding Baden), UK
What is mineralisation
Process by which soil organisms break down sugars, starches, nitrogenous compounds and cellulose.
what is sieving
Clay particles carried with water draining through soil and deposited lower down, formin a layer which prevents drainage and aeration of soil.
This macronutrient regulates cell acidity, important component of cell walls
Calcium (Ca)
Mediterranean climate is charachterised by :
(temperpature, rainfall)
- low anual range of temperature (warm, sunny summers, mild winters)
- dry summers, most of the rain falling during the winter
What is Dolomite
Sedimentary; similar to limestone but with higher magnesium.
What type of wines are often produced in hot climate?
little examples but f.e. Jerez
What are the disadvantages of sloping?
- increased risk of erosion (also influenced by rain intensity, soil texture and structure)
- higher costs
- steeply sloping vineyards will have to be managed entirely by hand
What is the major factor determining the suitability of a region for vituculture?
temperature
What is GDD?
Growing Degree Days
Why does the GDD-system work adequately in Calofornia?
- Because temperature variability, sunlight, humidity are correlated with degree days there.
- Because sunlight angle, day lengtht do not vary greatly across the region.
What is Limestone
Sedimentary rock, formed from shells and skeletons of marine animals. Largely calcium carbonate; free draining.
The particles in soil are graded according to their diameter as :
0 < clay < 0,002 < silt < 0,02 < fine sand < 0,2 < sand < 2 < gravel < 2 +
EU zone A : enrichment may not rise the total alcohol to more than?
11,5 % for whites
12 % for reds
The availability of rainfall to the plant depends on :
- the soil type
- the season
- the rate at which the rain falls
- vine density (less density => more water / vine)
- soil water holding capacity (gravel holds less water)
- when the rain falls (in Mediterranean climates most rail falls during winter)
What is Sandstone
Sedimentary; composed of clay; very soft.
The vine needs sufficient water to :
Conduct photosynthesis
Access nutrients in the soil
Ensure vine growth, yield potential, and fruit quality
Prevent its cells from collapsing and to function properly
Which ocean current warms up the climate to allow for wine production at latitudes normally too far north?
Gulf Stream (Atlantic–
Regions of high latitude (Mosel, S England, Central Otago– have an increased capacity to photosynthesize due to
Increased day length in summer
How many Growing Degree Days (GDD) in Amerine Winkler Category II
1370-1650
Where are maritime climates found?
Near large bodies of water e.g. Bordeaux, eastern coast of New Zealand.
What is puddling
when rainwater stays on surface of crust, extensive erosion
which macronutrient does one find a lot in a fertile soil?
what are the disadvantages?
- nitrogen
- encourages vigourous shoot growth
- can shade the fruit and inhibit ripening
- also makes increased demand on the sugars produced by photosynthesis
- less sugars in the grapes
- ripening gets slowed
- encourages vigourous shoot growth
PH for Acid soil
pH from 4 - 6.9
EU zone C : What is the maximum enrichment?
1,5 %
What are the principal climates for viticulture?
What is not such a good climate for viticulture
- Maritime climate
- Mediterannean climate
- continental climate
- tropical climate
What are the advantages and risk of exposing fruit to sunlight?
- It increases the rate of ripening
- => leaf removal around fruit zone several days before harvesting
- it increases the risk of sunburn
- helps eliminate pyrazines
- in some Bordeaux varieties
- would otherwise give the fruit “green” flavours
What is soil texture
The way in which soil particles form lumps or crumbs.
EU zone B : What is the maximum enrichment?
2 %
EU zone B : enrichment may not rise the total alcohol to more than?
12 % for whites
12,5 % for reds
Soil Macronutrients
Nitrogen (N
Phosphorous (P
Potassium (K
Calcium (Ca
Sulfur (S
Magnesium (Mg
What are volcanic rocks?
Formed from lava on the surface
What are disadvantages of Clay soils
- Take longer to heat up in spring; colder year round.
- Swell when they absorb water and shrink when they dry. Causes cracking, loss of water.
- can damage the root system
- Sticky when wet.
- Working wet soil deteriorates its structure.
What produces the finest tastes and aroma’s?
Slow, cool berry ripening
How is the mesoclimate improved by location near mountain ranges?
- mountains give protection from excessive wind and rain
How many Growing Degree Days (GDD) in Amerine Winkler Category IV
1930-2200
What is humus?
The matter that remains after mineralisation is decomposed much more slowly and forms a black and brown mixture of partially decomposed organic matter.
What is Slate
Shale that has been metamorphisized (changed by high pressures and temps–
benefits or problems for :
winter rainfall
spring rain
summer rain
autumn rain
winter rainfall :
- little effect on vine growth
- some water can be stored for later
spring rain
- moderate rain is beneficial
- it promotes schoot growth
summer rain
- some is usefull
- it can encourage disease
- it can reduce fruit set
autumn rain
- nearly always detrimental to the quality of the crop
How can the close proximity of forests be advantageous?
- they act as windbreaks
- they store heat in cold weather
- they reduce erosion
Mesoclimate is influenced by :
- aspect and slope
- water (bodies of water)
- vegatation
In what circumstances and where are north facing aspects preferred?
- In the southern hemisphere in cool climates
- it increases the sunlight that it receives.
- It faces the sun during much of the day
- the are warmer and wil aid the ripening proces.
- in the northern hemisphere that would otherwise be too warm
This macronutrient is key element in energy fixation. Encourages root growth and ripening process.
Phosphorus (P)
Calculate GDD for June if the mean temperature is 15°C
(15 - 10) x 30 = 150 GDD
This macronutrient is major constituent of plant cell proteins, nucleic acids, chlorophyll and hormones. Second to water in importance for plant growth.
Nitrogen (N)
What are the main things to notice in the EU-zone of production system, as the region gets warmer?
- the minimum potential alcohol requirement increases
- level to which must can be enriched decreases
- deacidification become illegal and acidification becomes legal.
This macronutrient is essential component of chlorophyll, regulates internal acidity, sugar metabolism, encourages ripening.
Magnesium (Mg)
What type of wines are often produced in moderare climate?
Medium-bodied wines
Name some typical cool climate regions
Champagne, Mosel, South England, Marlborough, Anderson Valley, Tasmania and parts of Carneros.
How does sunlight reduce in intensity according to the angle at witch it hits the ground and explain.
- The intensity reduces as the angle gets closer to zero. Highest at 90 degrees.
- the ligth beams have to travel trough a greater thickness of atmosphere tot get to the ground => more energy being absorbed
- the available sunlight is divided out over a larger area of land.
*
Aeration of the soil is essential because
- Provides oxygen
- to aerobic organisms and suppresses the growth of anaerobic organism
- to roots for respiration and growth
- Removes CO2
What regions are in EU region C 1a
Bordeaux, South West France, Rhone, Vinho Verde
What regions are in EU region C3a
Parts of Greece
In what circumstances and where are south facing aspects preferred?
- In the northern hemisphere in cool climates
- it increases the sunlight that it receives.
- It faces the sun during much of the day
- the are warmer and wil aid the ripening proces.
- in the southern hemisphere that would otherwise be too warm
Regional climate is called
Macroclimate
The texture of soil with ideal fertility. Why?
- loam (balanced mixture of clay, silt, sand)
- the texture of soil with ideal fertility
- combine nutrient-holding abilities of clay with the good drainage capabilities of sand
- disadvantage : rich, loamy soils can encourage too much vegetative growth and shading of fruit.
Soils that have higher pH
consequences?
Limestone
Inhibits update of iron
Increased risk of chlorosis
What is the limitation of applying Heat Summation as defined by Amerine and Winkler for California?
the relationship between vine growth and temperature is not linear, with growth slowing significantly over 30°C.
Regions with Slate soil
Mosel
What kind of wines and what region are best in Amerine Winkler Category I
Producing finest light-bodied white wines. Areas include Chablis, Mosel Valley and Champagne.
This macronutrient regulates flow of water and sugar in plant, encourages ripening.
Potassium (K)
What grape varieties grow best in moderate climate (16.5-18.5 C average mean temp. during growing season)
Medium body wines from intermediate ripening varieties. Cabernet Sauvignon, Merlot, Sangiovese.
How did Amerine and Winkler discover their system?
They found that the quality of wines produced in California reflected the heat summation of the sites on which they were produced.
What is calcium?
- Ca
- macronutrient
- Regulates cell acidity
- important component of cell walls.
Water holding capacity of soil determined by
Structure and humus content.
Availability of water for a vine is influenced by
Water holding capacity of soil.
why are climate indices useful?
- They are useful for evaluating potential and existing vineyard sites
- for determining which varieties are most suitable
On what does the amount of sugar in the grapes depend?
On the balance between :
- the amount of sugar created by photosynthesis
- increases with sunlight, not temparature
- the vines other metabolic needs
- increases with temperature
What is Chalk
Sedimentary rock, formed from shells and skeletons of marine animals. Largely calcium carbonate; even more free draining than limestone.
What double disadvantage face west facing vineyards?
- their sunlight will be scattered more by dust that has been lifted by warming air during the day
- they tend to face damper, cooler prevailing weather conditions
What grape varieties grow best in cool climates (below 16 C average mean temp. during growing season)
early ripening varieties will just ripen. Chardonnay, Pinot Noir.
The west coast of the UK is with 50 - 52° latitude normaly too far north to have sufficiently hight temperatures for ripening. What warms up the climate?
Gulf Stream (Atlantic–
What are the big problems for the few sub-tropical regions where vine growing occurs and where is that?
- the lack of winters can mean the vine crops more than once a year.
- There is no dormant period in which to “rest” and consolidate their carbohydrate reserves causes a shortended productive lifespan
- some areas in India and Brazil
What kind of wines and what region are best in Amerine Winkler Category IV
The best fortified wines.
EU zone CI : enrichment may not rise the total alcohol to more than?
12,5 %
What regions are in EU region C2
Languedoc-Roussillon, Provence, Northern Spain (except Atlantic coast), most of Italy
What regions are in EU region C3b
Portugal (except Vinho Verde), South Spain, Puglia, Sicily, Most of Greece.
EU zone A : What is the maximum enrichment?
3 %
This elements are essential for plant growth but they are taken from air not soil
Oxygen (O), Carbon (C), Hydrogen (H)
Why are bodies of water near a vineyard usualy regarded as a positive feature in a cooler climate?
- they reflect the sun’s rays
- they store heat late in the ripening season and release it to adjacent vineyards
- They moderate winter and summer temperatures
- they provide a source of water for irigation
- the reduce the risk of ground frost
- they can provide morning mists to encourage the development of “noble rot”, which may be desirable.
In cooler regions, a vine needs ______________ mm/year precipitation.
500
EU zone B : What is the amount of natural alcohol?
8 %
What is heavy soil?
- high clay or silt content
- holds more water
- holds more minerals (as the particles are slightly negatively charged)
Hail is a serious problem in
Mendoza
Burgundy
Piemonte
What grape varieties grow best in hot climate (over 21 C average mean temp. during growing season)
Table and drying grapes
Why are tropical and sub-tropical conditions considered unsuitable for high quality viticulture?
The vine needs clear temperature signals for its dormant periods and growht cycles. even in locations where temperature is moderated by altitude of proximity to cool oceans.
The amount of available sunshine decreases by up to 10% if the vineyard is close to a town or city, due to ________________.
Pollution effects
This macronutrient is essential constituent of some amino acids and enzymes
Sulfur (S)
high sunshine and high temperatures can lead to …
berry scorching
What’s the most widely used climate indice ?
- system developped by Smart and Dry for Australia
- It uses the mean temperature of the warmest month with corrections for continentality, sunlight hours and day length (related to latitude), humidity, rainfall and evaporation
How many Growing Degree Days (GDD) in Amerine Winkler Category V
Over 2200
What is the average mean temperature during the growing season for cool climate?
Below 16°C
Mediterranean climate is ideal for what kind of wines? Give also examples.
full-bodied, richly-textured red wines with ripe tannins
What kind of wines and what region are best in Amerine Winkler Category III
Premium full bodied red wines. Regions include Barossa Valley, Stellenbosch, South Rhone.
Why does the vine’s demand for sugar increase?
Because its metabolism icreases.
Vine growing regions can be classified according to 4 big groups of average temperature. Which?
- Cool
- Moderate
- Warm
- Hot
Glucose is a buidling block for
the vine
the creation of tannins
the creation of acids
the creation of flavour molecules
In what climates are most high quality wines produced?
In climates that are only just suitable for vine culture.
What kind of wines and what region are best in Amerine Winkler Category V
Adapted for bulk wines, and table and drying grapes.
The 2 important parts of the growing environment
- Climate and weather
- soil
What’s another word for microclimate?
Canopy climate
Site climate is called
Mesoclimate
Frequently cultivated, shallow soil in low rainfall area will be deficit in which nutrients
Nitrogen
Soil texture is :
The size of the particles that make up a soil and their proportions relative to each other.
What are advantages of Clay soils
retain more moisture, more minerals
Climate and weather consist of :
- macroclimate
- mesoclimate
- microclimate
- temperature
- precipitation
- sunlight
- geographical features affecting climate
Sunlight’s effects on vine growth
- Heat accumulation (indirect effect)
- Bud viability, initiation of flowers, berry ripening, cane maturation. (direct effect)
- Rate of photosynthesis (direct effect)
What is the average mean temperature during the growing season for warm climate?
18,5 to 21 °C
Poor soil structure can lead to
- Capping/crusting
- Puddling (rainwater stays on the surface–
- Sieving (clay particles are carried along with water and deposited further down forming a layer that prevents drainage–
explain the influence of water-stress
- some water-stress during berry maturation can improve the quality of the crop
- severe stress however halts vegetative growth and will cause leaf loss.
When is the growing season in the southern hemisphere?
October to April?
Regions with Volcanic soils
Santorini
Madeira
Where are Mediterranean climates found?
Troughout the Mediterranean sea, west coast of the United States, most of the Chilean wine regions, many regions in South Eastern Australia, Cape winelands of South Africa
Where are Continental climates found?
Inland e.g. Mendoza, central Europe, central Spain
Soil acidity is measured by the
pH scale
What is required by the vine to complete its anual growth cycle?
Enough heat for a sufficient lenght of time.
What constitutes the growing environment?
- temperature and sunlight, 2. water,3. nutrients,4. climate,5. weather,6. climate change.
What is vineyard management aimed at?
At making best use of the natural resources available.
What will have a a DEFINING influence on the wine produced: the growing environment or the winemaker’s operations with the must/wine?
the growing environment and its effect on natural resources.
What’s the optimal temperature for the dormancy of the vine?
under 10°C, extreme temperatures (around -20°C) can cause winter freeze and damage the vine.
What’s the optimal temperature for budburst?
above 10°C,+ a significant rise in temperature.
What’s the optimum temperature range for shoot and leaves growth and photosynthesis?
18–33°C
What’s the optimum temperature for flowering? fruit set?
above 17°C.
What’s the optimum temperature for fruit set?
26–32°C.
What’s the optimum temperature to promote increased bud fruitfulness?
above 25°C.
How does warmth influence grape ripening?
- faster sugar accumulation (due to optimum photosynthesis, increased grape transpiration) 2. malic acid decrease3. a rapid loss of acidity (mean t above 21°C in the final month of ripening)4. riper aroma/flavours
Define photosynthesis.
is a biochemical reaction where leaf combines CO2 + water to produce glucose + oxygen.
Define transpiration.
Transpiration is a biological process when water travels from the roots to small pores underside the leaves - stomata. The leaf pores stomata diffuse water OUT and let CO2 for photosynthesis IN. The released water transforms into vapor (испарение) and it evaporates into the atmosphere.
How does cool temperatures influence grape ripening?
- reduce acid loss (mean t below 15°C in the final month of ripening) => acidity levels in the must are too high,2. hinder the breakdown of methoxypyrazines (herbaceous aromas),3. slow down anthocyanin synthesis (development of colour in black grapes),4. most likely slow down tannin synthesis.
What is the optimum t range for anthocyanin synthesis (colour)?
15–25°C
How can extreme heat and conditions affect grape ripening?
- slow or stop photosynthesis
Why can photosynthesis slow/stop during heat?
- due to the heat sensitivity of enzymes (that catalyse photosynthesis),2. water stress => shutting of stomata to prevent water loss => the closed stomata limit intake of CO2 (which is needed for photosynthesis).
What’s the amount of sunshine optimal for photosynthesis?
NOT full sunshine, below 1/3 of full sunshine.
What are the effects of grape exposure to sunshine?
- enhancing of anthocyanins (colour pigments),2. the reduction of methoxypyrazines (herbaceous aromas/flavours),3. accumulation of tannins (pre-véraison),4. promotes tannins polymerisation (after véraison) => less bitterness,5. increased levels of favourable aroma precursors and compounds (terpenes for fruity and floral aromas),6. lower acidity levels (malic acid is used up intensively in grape RESPIRATION when grapes are warmed up),7. successful fruit set (sunshine in late spring / early summer),8. promotes bud fruitfulness in next year’s growing season (due to exposure of compound buds), 9. ‘–’ sunburn on sun-exposed grapes.
How is latitude correlated with solar radiation QUANTITY?
Regions at LOWER latitudes (nearer the Equator, e.g. Mendoza, South Africa, New South Wales) will receive MORE solar radiation per annum than regions at higher latitudes (nearer the Poles, e.g. northern France and Germany).
How is latitude correlated with solar radiation INTENSITY?
Regions nearer the Equator (at lower latitudes) receive more intense solar radiation than those nearer the poles (at higher latitudes).
Why solar radiation is less intense nearer the poles (at higher latitudes)?
- solar radiation must travel through a larger section of atmosphere to reach the Earth’s surface,2. solar radiation is more diffuse (the radiation hits the Earth at a low angle, so the radiation is spread over a larger area).
What are characteristics of grapes grown at lower latitudes compared to those at higher latitudes?
higher levels of sugar, lower levels of acidity, riper aromas,higher but riper tannins and more colour intensity (in black grapes).
How is latitude correlated with The number of hours of solar radiation?
Low latitude regions => similar daylight hours throughout all seasons.High latitude regions => longer daylight hours in the summer and shorter daylight hours in the winter => a longer duration of time over which photosynthesis can take place in the growing season => helping the vine to produce enough sugar even in cooler temperatures.
What latitudes are suitable for growing wine production grapes?
Bw 30° and 50° latitude on each side of the Equator.
