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soil resources (Fach) / testing exam (Lektion)
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Diese Lektion wurde von tinalinea92 erstellt.
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- what are the main processes leading to chemical degradation in arid climates compared to Germany? - salinization - pH changes of the soil - contamination of toxic elements/ substances - leaching salt into water - irrigation water and groundwater table - saltenrichment through rainfall - leading to chemical degradation because of water deficite and extreme clima, solar radiation, temperature and soluble salt
- what was the annuel average temperature wenn the soils like: Saprolite, Terrae Calic, Solum of Feersialit and Ferralit were formed. Which animals were found in costal areas, that now are used as ligne pit mining areas? - warm humid climate, tropical climate conditions - subtropic -fossile relic weathering - animals are fishes and mollusca, marine animals, elephants
- which tropical and subtropical soil types did we find among our field trip to mainze? Saprolite, Terrae Calcis, Solum of Feersialit, Ferralit
- Characteristica of Alisols, CEC of the clay fraction and base saturation high CEC, > 24 cmol/kg, much exchangable Al in argic horizon low base saturation <30%, acid soils material argic horizon with high activity clays and alic properties low pH and Al and Mg toxicity
- Acrisol, what CEC and base sat? low CEC, <24 cmol/kg, strongly leached and red and yellow clay accumulation horizon low base saturation < 50%, low nutrient availability and P sorption and Al toxicity
- Lixisol, CEC and base sate low CEC, <24 cmol/kg, low activity clays high base saturation > 50%! higher soil pH than ferralsols, no Al toxicity also argic horizon
- Luvisol, ..... CEC? high CEC clay
- describe principle step towards soil classification of the second level of WRB qualifier are differing the groups from the first step of the WRB into 3 other groups 1. qualifier groups the RSG through typical characteristics 2. secon groups differs after the diagnstic horizon - between horizons the RSGs are signed with prefixes before and suffixes afterwords 3. thrid step the qualifier differ the RSGs through other characteristics like nutrientavailability or conten
- where are Podzols mostly prominent over the world? which factors promote the podzolaion process? which land use options do you recommend for Podzols? - humid areas, boreal and temperate zone, zonal: northern hemisphere, also in tropics and russia, scandinavia; intrazonal: temperate zone - high precipitation and lower evaporation, organic matter fall/ input, leaching, weathering of primary minerals - plugging management, fertilizer and plougging agroforstry, extensive grazing and natural vegetation
- which problems when cultivating organic soils ? how can these problems be minimized? - loss of nutriens and carbon through tillage and working on.., erosion, winderosion, greenhouse gas emission increasing, oxidation of soils organic matter, soil shrinking and erosion and degree of water level - minimized with.. adapted crops against wind erosion, perennial gras f.e., nurientfertilizer while growing status, less soil working on, drainage and fertilization, burning of peat
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- which special minerals occur in Andosols - volcanic soils, and which typical physical features do they cause in th soil? imogolite, allophane, ferrihydrite, hallosyte - good water holding - high porosity - rapid weathering and formation of cristalline gellike minerals in the soil - high phosphate retention > 85%
- intwo which two groups would yo subdived the weakly developed soils? - parent material is calcareous -> Rendzic Leptosol or the parent material is acid --> Dystric Leptosol with base saturation < 50%
- typical profil of a paddy soil athropogenic soil, made by man with a red loose A horizon, underneath the Ardp, Ap dense and than comes the B horizon Ap horizon includes the plowpan than comes the Br with redox features -> plow sole is characterisitic made by plowing wet and horizon thereby highly compact, homgenous formed upper soil above the plow sole Ap(cultivated horizon including plowpan), Ardp (diagnostic horizon for paddy soil), Br(redox features possible with grey film)
- where do you commonly find Chernozems, Kastanzems and Pheaozems, and what makes the difference betweeen these major soil groups? normally find them under grassland and steppe -> tall short grass prarie difference is the precipitation!!!! and than the color and leaching Phaeozem -> oldest soil of the three, under higher precipitation, near to steppe/forest, more leached than the others, with good water holding capacity!!!, much humus and good pH, precipitation 500-550 Chernozem -> black soil, very fertile, underground chalky and over it rubbish/mull, no washing out and clack color!! 500 mm/a Kastanozem -> youngest soil, color more like hazelnut/ chestnut, less precipitation, 200-400mm/a no washing out and much lime
- what are ferralsols and where do they occur? add five main characteristics of their genesis and or properties - occour in tropics, humid climates, humid tropic - soth america and Africa - old continental shields - very old, strongly weathered soil, deeply weathered and sour, acid - oxic hrizon - 15% clay content!! - with fe and Al -> ferralic horizon - low CEC, low base saturation and Pfixation - clay destroying of intensive weathering leads to accumulation of sesquioxides -> no nutrient availability
- 6 five stable factor for soil forming 1. time 2. climate 3. parent material 4. topography 5.Biota 6. human activities
- what is a cambic horizon? Bw horizon with higher clay content than parent material
- Chelat binding - ? mobilization and precipitaion complex formation with Fe3+ and Al3+
- where and why complex binding? because of organic matter saturation! -> higher pH values -> higher pH with increasing soil depth
- when Podzol = Podzol? white bleached horizon, underneath a humic horizon umid climate, northern hemisphere, temperate zone and tropic zone horizon -> 2m of soil, spotic!, horizon below organic matter, colourin substances -> iron and quarz, leaching and low pH <4 low in nutrients and microbial activity coniferic forest
- what connects the clay enriched soils? vertical translocation as the connecting element
- what are the tree vulcanic parent materials? and how is the silica content ? Rhyolite with 65-70% SiO2 Andesite with 55-65% SiO2 and Basalt with 45-55% SiO2
- what characterises Vertisols? - swelling clays with high amount of clay more than 30% mostly dark colored rich in smectites swelling and shrinking no stabil structure - difficult for plants to grow on soil
- characteristics Histosols lack oof oxygen caused by waterlogging acidic and salt content high toxic, cool temperatures accumulation of peat
- what is Löß? aeolian deposit from the last late glacial periods -high water retention and very fertile and rich in K neutral pH -> high and safe yields and high available yield capacity
- what characterises the high activity clay?? 1. mobile clay -> mobilization 2. transport 3. immobilization of clay in subsoil
- what characterises Planosols? abprupt textural changes between soilhorizon no layering
- what is an argic horizon? clay accumulation horizon with an higher clay content than the overlaying horizon
- how du you differentiat th weakly developed soils into two groups? 1. due to rooting under stoniness and permafrost conditions -> Leptosols (swallow) and Cryosols (ice affected soils) 2. due to age and no horizontation/profile -> Regosols (young soils) and Cambisoils (moderately developed)