Next climate. vine one of the most important factors influencing wine quality. The various soil types have developed over millions of years through physical and chemical weathering of rocks and through the humification of organic matter (see also under geology ). In physical weathering, natural forces such as wind, water, heat, cold and ice initially cause the rock formations to be mechanically crushed into rubble and gravel. Strong temperature opposites, friction and shear forces as well as the frost blast caused by frozen water in rock fissures play an important role. Chemical weathering processes such as oxidation, Solution processes and acid attacks attack the mineral lattice structure of the rocks. Easily water-soluble minerals such as carbonates and Sulfate first dissolved, the rock slowly disintegrates into grus, sand, silt or clay. Every rock, even the hardest granite or quartz, will eventually crumble to dust, even if it takes millions of years.
Organic substances from plant residues, animal residues from worms, insects and small animals of all kinds, as well as dead ones microorganisms such as seaweed. bacteria and mushrooms are in humus converted. The essential for plant growth nitrogen compounds (Nitrate, ammonium) as well as others nutrient released. Fungi and bacteria play the main role in the decomposition of organic residues such as wood, leaves, roots or animal corpses. Insects such as floor mites are important because of their crushing feeding activities. Earthworms play a crucial role in soil loosening, mixing and the formation of stable clay-humus complexes, which are formed in the earthworm intestine and excreted as faeces. These contribute to the structural stability of the soil and can bind easily water-soluble nutrients and thus make them available to the plants for longer.
Each floor consists of floor horizons (soil layers) with special properties. They are almost always horizontal and can be seen in the soil profile (vertical section of the soil in an excavation). The sequence is the essential criterion for determining the soil type. From top to bottom, a soil is divided into an organic soil horizon or HLO horizon (peat from plant residues, litter) and a three-part mineral horizon. These are A-horizon (mineral topsoil with a lively, humus-rich layer), B-horizon (mineral subsoil with a low-humus layer with fine soil already chemically weathered to sand, silt or clay) and C-horizon (little changed starting rock with physical weathering). Deep mechanical tillage mixes horizons. Depending on the climate and Erosional action the A or B horizon may also be missing or only marginal.
In a vineyard, the horizons have usually already been mixed up by tillage. Rock subsoil, initial soil, tillage, fertilization and water balance with a balanced ratio between the Water storage capacity and the water discharge shape alongside the local climate (Microclimate or layered climate) the location vineyard and give each vineyard location the typical and unmistakable character of the origin, The duration of the growth cycle, the orientation of the exposition (Solar radiation) and the local climate on the slope, the existing soil conditions, the Humus- and lime content and the water supply affect the choice of the most appropriate varieties,
The well-known geologist and wine book author James E. Wilson aptly writes in his book "Terroir - Keys to Wine": "The soil is the soul of the grapevine" . However, the direct connection of rock, grape variety and wine character today is likely to be more rooted due to the uniform use documents with strong mineral fertilization and the use of new wine-growing cellar methods are only marginally pronounced. In the formerly sparingly and mostly organically fertilized vineyards with their old, ungrafted planted and often deeply rooted vines, this relationship certainly came into its own much more.
The French, in particular, recognized the importance of the interplay of climate-rock-soil-location-microclimate and grape variety very early on and in the creation of the term terroir elevated to their philosophy, so to speak. The terroir with the suitable grape varieties is used in the classification of the wine-growing regions as Appellation d'Origine Protégée (AOP) legally defined. This is a clear difference to the philosophy, for example, in Germany and Austria, where great importance (not too much) is attached to the location of the grape variety and the vine variety obtained from it.
It is of great advantage if the Rebstock must drill its roots as deep as possible into the ground. Due to the ability of floors as ion exchanger To act, i.e. to exchange nutrient salts in the soil solution for the protons (H +) and anions (OH-) released by the plant, the supply of the roots with essential nutrients and trace elements made possible at all. The minerals ingested can be found in the total extract of a wine again. The vine needs around twenty essential trace elements and the main nutrients to thrive. As a permanent crop, it is less dependent on fertile soils than annual crops. There are often locations with very poor soils on which high-quality wines grow. However, this does not mean that the less nutrients are available in the soil, the better the wine quality.
A lack of nitrogen and amino acids in the must yeasts in the fermentation hinder and Gärfehler cause. Among other things, this can be due to the wine error UTA (atypical age tone). Rather, the harmonious composition of the nutrients in the soil, the availability of water and nutrients as well as the state of aggregation and the ability to be rooted are important for the suitability of a soil for viticulture. Through plant or soil tests using EUF method a lack of nutrients can be recognized and possibly caused by fertilization be resolved. A comprehensive classification or determination of the soil quality for agricultural use in general or specifically for viticulture is carried out using Bonitur,
With lime-rich soils pH values over 8 makes the high difficult Calcium level in the ground the absorption of other double positively charged ions such as Nitrogen Compounds. magnesium or the trace elements boron. iron. manganese or zinc, so that lime chlorosis or other physiological deficiency symptoms can occur, even with normally sufficient nutrient levels in the soil. Especially at the beginning of the growth cycle, the nitrogen content (in the form of nitrate and ammonium) in the soil should be sufficient. The basic rule is that alkaline (alkaline) soils with a high pH value above 8 (e.g. lime, chalk and marl soils with mostly a high proportion of calcium and magnesium) result in wines with a higher acidity, while acidic soils with a low pH value less than 6 to 4 (for example granite, quartz sand) cause wines with lower acidity. Experiments with increased amounts of potassium have shown that vines react with an increased malic acid production. To compensate for the increased influx of positive potassium ions, the plant produces negatively charged acid anions (malic acid). However, irrespective of the vintage or maturity-related acid values, other causes also contribute to the acidity in the wine.
A good Weingarten soil should be lean, medium to deep, well aerated, water-permeable and not compacted, rich but not too fat, not too humus rich but rich in mineral components. The best locations are so-called slopes, because this creates an almost vertical angle of incidence for the sun's rays in late summer, so that the maximum amount of radiation can be used. The best location on the slope is the calm, concave middle (belly, navel, kidney), where the highest temperature sums can be reached and the soil is usually well drained. Soil color also plays an important role, because dark soils absorb the heat of the sun more quickly and comprehensively, while light soils reflect light so that such soils do not heat up as quickly and as strongly. The suitability of an area for viticulture is called Weinbauwürdigkeit which can be determined using a criteria catalog.
Alberese: Italian name for the weathered sandstone found, for example, in the best Chianti areas (see also under Galestro).
Alluvium / Alluvion (alluvial soil ): Alluvial sediment washed up and deposited by water. The geological name for the floating is "fluviatil". Alluvium is also another name for the Holocene, the youngest geological age that has lasted since the end of the last ice age some 10,000 years ago. Alluvial soils are mostly fine-grained, very fertile soil types that arise in the flood and mouth area of rivers. They consist of soil particles that have been washed up and sedimented when water soothes.
Depending on the sinking rate of the soil particles carried in the water and the flow rate of the flood, they consist of clayey mud, silt, sand or in the immediate bank area with high runoff speeds and strong erosion dynamics of gravel and pebbles. Despite the predominantly rocky and sandy nature, such as in French Médoc, these floors are very suitable for viticulture. The secret of the locations there are the clay lenses deposited in various floods and covered with sand and gravel inside the alluvial gravel terraces, which can store water. Such layers of clay are literally sought by the vine roots.
Amphibolite: Mostly black over gray to dark green rock, which is the result of the metamorphic conversion of basalt (see below) under high pressure and temperature conditions. It consists of up to 50% representatives of the amphibole group such as hornblende (see below) or Tschermakit, and up to 40% from other minerals such as garnet and quartz, as well as ores such as magnetite and pyrite.
Aeolian: named after the Greek wind god Aeolus, phenomena caused by the wind. Aeolian transport triggers fine material such as loess, silt (silt) or clay from the raw material, such as loose rock, and transports it over long distances by the wind. Aeolian weathering refers to the removal of rock by sand grains, fine gravel, etc., which are moved by the wind, with the effect of a sandblaster. This creates an Aeolian weathering soil.
Arkose: The geological term describes a pink to reddish, coarse-grained sandstone with a high proportion of feldspar, which occurs mainly in dry, arid areas. It leads to the coarser granite stones.
Alluvial soils: Soils created from river deposits that are periodically flooded. Such come in, for example Danube-. Moselle- and Rheinauen in front. When they are no longer flooded, they develop into brown earth and para brown earth. These soils are mostly nutrient-rich, biologically active and fertile.
Basalt: Basic effusion rock (cooled magma) consisting of feldspar, hornblende, olivine and magnetite. It contains a lot of lime and soda and is rich in minerals. The hard, slowly weathering rock forms good soils and produces wines with an appealing acidity.
Pumice (pumice stone, pumice stuff): The porous, glassy volcanic rock is formed by gas-rich volcanic eruptions, in which the lava is foamed by water vapor and carbon dioxide. It is not chemically different from other lava, but is much lighter due to the trapped air. The color varies from black and with increasing air content to gray to white. The term Bimstuff refers to the grain size, at least 75% must consist of volcanic ash. Pumice soils...