Next climate. vine one of the most important factors influencing wine quality. The different types of soil have evolved in millions of years through physical and chemical weathering of rocks as well as through humification of organic matter (see also under geology ). In physical weathering, forces of nature such as wind, water, heat, cold and ice first cause the mechanical fragmentation of rock formations into pebbles and gravel. Strong temperature differences, frictional and shear forces as well as frost damage caused by frozen water play an important role in rock fissures. Chemical weathering processes like oxidation, Solution processes and acid attacks attack the mineral lattice structure of the rocks. This easily water-soluble minerals such as carbonates and Sulfate first dissolved, the rock slowly decays to grus, sand, silt or clay. Any rock, even the hardest granite or quartz will eventually crumble to dust, even if it takes millions of millions of years.
Organic substances from plant residues, animal residues of worms, insects and small animals of all kinds as well as dead ones microorganisms such as seaweed. bacteria and mushrooms be in humus transformed. At the same time, they become essential for plant growth nitrogen compounds (Nitrate, ammonium) as well as others nutrient released. In the decomposition of organic residues such as wood, leaves, roots or animal corpses mushrooms and bacteria play the main role. Insects such as ground mites are important because of their crushing feeding activities. Earthworms are critically involved in soil loosening, mixing and the formation of stable clay-humus complexes that are formed in the earthworm gut and excreted as feces. These contribute to the structural stability of the soil and can easily bind water-soluble nutrients and thus make longer available for the plants.
Each soil consists of soil 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 a excavation). The sequence is the essential criterion for determining the soil type. From top to bottom is a soil divided into an organic soil horizon or HLO horizon (peat from plant remains, litter) and a tripartite mineral horizon. These are A-horizon (mineral topsoil with animate, humus-rich layer), B-horizon (mineral subsoil with humus-poor layer with fine soil already chemically sand, silt or clay) and C-horizon (little changed source rock with physical weathering). Through deep mechanical tillage horizons are mixed. Depending on the climate and Erosional action The A or B horizon may also be missing or only marginally formed.
In a vineyard, the horizons have usually already been mixed by tillage. Underground, bottom, tillage, fertilization and water balance with a balance between the Water storage capacity and the water discharge shape next to the local climate (Small climate or climate layer) the location vineyard and give each vineyard location the typical and distinctive character of the ancestry, The duration of the growth cycle, the alignment of exposition (Solar radiation) and the local climate on the slope, the existing soil conditions, the Humus- and lime content and the water supply influence the choice of the most suitable varieties,
The well-known geologist and wine-book author James E. Wilson aptly writes in his book "Terroir - Key to Wine": "Soil is the soul of the grapevine" . However, the direct relation of rock, grape variety and wine character is often due to the common use rooted more shallow documents with strong mineral fertilization and the use of new viticultural Kellermethoden be only marginally pronounced. In the formerly sparingly and mostly organically fertilized vineyards with their old, ungrafted planted and often deeply rooted in the rock vines this relationship was certainly much more effective.
Especially the French have recognized the importance of the interaction of climate-rock-soil-location-small-climate and grape variety very early on and this in the creation of the term terroir elevated to her philosophy, so to speak. The terroir with the suitable grape varieties is used in the classification of wine regions as Appellation d'Origine Protégée (AOP) defined by wine law. This is a clear difference to the philosophy, for example, in Germany and Austria, where not the location, but mainly the grape variety and the resulting pure varietal vintage wines is given great (too much) importance.
Of great advantage is when the Rebstock must drill its roots as deep as possible into the ground. Due to the ability of soils as ion exchanger To act, ie to exchange nutrient salts in the soil solution against the protons released by the plant (H +) and anions (OH-), the supply of the roots with essential nutrients and trace elements made possible in the first place. The absorbed minerals are found in total extract a wine again. The vine needs around twenty essential trace elements and the main nutrients to thrive optimally. As a permanent crop, it is less dependent on fertile soils than annual crops. It is not uncommon for vineyards with very poor soils to grow quality wines. But that does not mean that the less quality of nutrients is available in the soil, the better the quality of the wine.
A lack of nitrogen and amino acids in the must the yeasts in the fermentation hamper and Gärfehler cause. Among other things, this may be due to the wine defect UTA (untypical age tone). Rather, the harmonious composition of nutrients in the soil, the availability of water and nutrients as well as the state of aggregation and rooting are of importance for the suitability of a soil for viticulture. Through plant or soil tests by means of EUF method a lack of nutrients can be detected and possibly through fertilization be resolved. A comprehensive classification or determination of the soil quality for agricultural use in general or specifically for viticulture is carried out by means of Bonitur,
On calcareous soils with pH values over 8 hampers the high Calcium level in the ground recording other doubly 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 adequate 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. As a general rule, alkaline (alkaline) soils with a high pH above 8 (for example, lime, chalk and marl soils with mostly high levels of calcium and magnesium) will produce wines with higher acidity, while acid soils with low pH Under 6 to 4 (for example, granite, quartz sand) cause wines with lower acidity. Experiments with increased potassium supplements have shown that vines react with increased malic acid production. To compensate for the increased influx of positive potassium ions, the plant produces negatively charged acid anions (malic acid). However, other causes (irrespective of vintage or maturity acidity) naturally contribute to the acidity in wine.
A good vineyard soil should be rather lean, medium to deep, well aerated, permeable to water and not compacted, rich but not too fat, not too rich in humus 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, and thus the maximum of radiation can be exploited. The best location on a slope is the wind-calmed concave center (belly, navel, kidney), where the highest temperature sums 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 so quickly and not so much. The suitability of an area for viticulture is called Weinbauwürdigkeit, which can be determined by means of a list of criteria.
Alberese: Italian name for the weathered sandstone occurring, for example, in the best Chianti areas (see also Galestro).
Alluvium / Alluvion (alluvial soil ): Alluvium / Alluvium flooded with sediment. The geological name for the flooding is "fluviatil". Alluvium is also another name for the Holocene, the most recent and since the end of the last ice age about 10,000 years to this day enduring geographic era. Alluvial soils are mostly fine-grained, very fertile soil types, which arise in the flood and estuarine areas of rivers. They consist of heranzülülten and absedimentierten in water sediment soil particles.
Depending on the sinking rate of the soil particles entrained in the water and the flow velocity of the flood, they consist of clayey mud, silt, sand or in the immediate vicinity of the shore with high discharge rates and strong erosion dynamics of gravel and pebbles. Despite predominantly rocky and sandy texture, as for example in the French Médoc, these soils are very suitable for viticulture. The secret of the local layers are deposited during various floods and covered with sand and gravel clay lenses inside the alluvial gravel terraces that can store water. Such clay layers are formally sought by the vine roots.
Amphibolite: For the most part black over gray to dark green rock, formed by the metamorphic transformation of basalt (see below) under high pressure and temperature conditions. It consists of up to 50% of representatives of the amphibole group such as hornblende (see below) or Tschermakit, and up to 40% from other minerals such as garnet and quartz, and ores such as magnetite and pyrite.
Aeolian: named after the Greek wind god Aeolus, appearances caused by the wind. By an Aeolian transport fine material such as loess, silt (silt) or clay from the source material such as loose rock is triggered and transported by the wind over long distances. Aeolian weathering refers to the removal of rocks by sand grains moving through the wind, fine gravel etc. with the effect of a sandblast blower. This creates an aeolian weathered 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 more granular granitic rocks.
Floors: Floors resulting 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 parabraun earth. These soils are mostly nutrient-rich, biologically active and fertile.
Basalt: basic effusion (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 soil and produces wines with appealing acidity.
Pumice (pumice stone, Bimstuff): 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 does not differ chemically from other lava, but is much lighter due to the trapped air. The color varies from black and with increasing air content over gray to white. The name Bimstuff refers to the grain size, at least 75% must consist of...