Einfluß der NO3- bzw. NH4-Ernährung auf Ertrag und Nitratgehalt von Spinat und Kopfsalat

Influence of NO₃ and NH₄-nutrition on yield and nitrate content of spinach and lettuce Field and pot experiments were conducted in order to study the effect of N-supply (N_min + N-fertilization) and partial and complete NH₄-nutrition on yield and nitrate content of spinach and lettuce. The highest yields were obtained when the N-supply of spring spinach was 250 kg N/ha, autumn spinach 200 kg N/ha and lettuce 120 kg N/ha. Nitrate content of plants could be diminished by reducing N-supply. However, if N-supply is below the optimum value yield depressions are inevitable. NH₄-nutrition reduced in both species nitrate content. But, spinach yield was reduced heavily. Very low nitrate content of plants occured, when N-nutrition of plants cultivated in nutrient solution, was changed from NO₃ to NH₄ during the last days before harvest. Herewith similar weights and head quality were obtained as with permanent NO₃-nutrition.     

Eine Titrationsmethode zur simultanen Bestimmung von H+ und Aluminium in NH4Cl - Bodenextrakten

A Titration-Method for the Simultaneous Analysis of H⁺ and Aluminium in NH₄Cl-Soil Extracts A method for the simultaneous potentiometric titration of H⁺ and Al in NH₄Cl soil extracts was developed. An automatic titrator (METROHM E 636) was used. The reagent was 0.04 M NaOH. The method was first tested using standard solutions containing H₂SO₄ and AlCl₃. The pH-curve consistently showed 2 clearly defined end points at pH-values near 4.2 and 5.6. The measured concentrations varied between 95 and 99% of the theoretical values. Testing with real soil extracts resulted in nearly identical pH-curves and demonstrated the basic suitability of the method. The analytical error is lower than 5%.     

双阻NH4+选择性微电极测定水稻叶片细胞中NH4+的活度

本文介绍了双阻NH4+选择性微电极的制作方法、工作原理及操作方法。微电极电位响应値与溶液中NH4+的活度呈对数曲线的关系,NH4+选择性微电极与其他类型的电极(如H+、NO3-)最大区别是K+的干扰,在含有72 mmol/L K+的标定溶液中,电极标定曲线的斜率为48~58 mV,对NH4+的检出限小于10-4 mol/L,说明电极对NH4+有较高的选择性,受K+的影响较小,可以用来测定。用以测定2.5 mmol/L NH4+培养2周的水稻叶片,结果表明,叶片细胞中NH4+活度分布在高低不同的两个区间内,分别代表了细胞质和液泡中的测定,水稻叶片细胞质和液泡NH4+的活度分别为2.58~9.30 mmol/ L和11.36~25.20 mmol/L。水稻叶片组织中的NH4+主要来自液泡,流动分析仪测定的水稻叶片组织的NH4+浓度为11.12 mmol/L。NH4+选择性微电极为研究水稻对NH4+的吸收利用提供了技术支撑。     

Simultaneous extraction of P and K from IOWA soils with bray 1 solution containing NH4Cl

Abstract

The effects of combining the Bray 1 extracting solution with ammonium chloride (NH₄C1) for simultaneous extraction of P and K were studied in several experiments. For pooled data from the experiments in which the Bray 1 solution containing 0.5 mol L^‐1 NH₄C1 was used, the relationship between the amounts of P and K extracted by the combined solution (P_C and K_C)and the amounts extracted separately by Bray 1 (P_R) and 1 N neutral NH₄OAc (K_R) are given by P_C = 2 + 0.906 P_R, r = 0.988 and K_c = 14 + 1.033 K_R, r = 0.944. Variations were observed in different experiments when the concentration of NH₄C1 and the conditions of the experiment were varied.     

Der Einfluß des NO3 : NH4 -Verhältnisses in der Nährlösung auf Ertrag und Gehalte an organischen und anorganischen Ionen von Tomatenpflanzen

The influence of the relation between NO₃ and NH₄ in the nutrient solution on yield and organic and inorganic ion contents of tomato plants. . Tomato plants were grown in aerated media of oppositly varying supply of (NH₄)₂SO₄-and NaNO₃ with a constant N-quantity of 15 meq/1 or a quantity of NH₄-, NO₃ or (NO₃ + NH₄) increasing from 3 to 30 meq.N/1. Yield and ion content were determined. A maximum yield was achieved by a mixed N-supply i.e. 4 to 5 parts NO₃, 1 part NH₄-N and 7, 5 meq N/l. The “(C-A) value” was calculated by the content of the cationions “C” (=K⁺ + Na⁺ + Ca⁺⁺ + Mg⁺⁺ + NH₄⁺) and the inorganic anions “A” (= NO₃^? + Cl^? + H₂PO₄^? + SO₄^–). The “(C-A)” value is equivalent to the content of the organic anions. Furthermore we determined the citrate, malate, oxalate, and pektinate content. These make up 60–80% of the (C-A) value. The NO₃- and K content increase considerably, the Ca-, Mg-, Na-, Citrate, Malate and Oxalate content increase less pronounced, the Cl-, H₂PO₄- and SO₄- content decrease as the NO₃ content increases from 0–80%. If the medium contains 80–100% NO₃ - N, the NO₃ and K content remain almost constant, while the Ca-, Mg-, citrate, malate and oxalate content especially increase in this case. The K content decreases in the presence of a high (NH₄)₂SO₄ supply. Parallel to this the value (C-A) decreases greatly, so that it is less than the sum of the determined organic anions. In this case the content of organic anions obviously does not correlate with the (C-A) value. The yield correlates with the carboxylate contents. (C-A) values of 150–170 mval/100 gm. d. m. cause a lowering of the yield. The plants contain an almost equal amount of citrate, malate and oxalate. Depending on the N-concentration of the medium, the malate content will be a bit more than the amount of citrate in case of maximum yield. If there is a lack or toxicity in the medium the citrate content will be higher than the malate content. The yield per dry weight correlates positivly with the quotients of citrate and malate.     

Beziehung zwischen dem Stickstoff-Entzug der Pflanzen und der Abnahme von spezifisch gebundenem NH4-N im Boden

Relationship between the N uptake of plants and the mobilization of nonexchangeable NH₄-N In a pot experiment with ryegrass (Lolium multiflorum) the relationship between the release of nonexchangeable NH₄⁺ and the N uptake of plants was studied. For this purpose the surface soil of an alluvial soil and of a grey brown podsolic soil was labelled with ¹⁵NH₄-N. The following results were obtained: After treating the soil with 15-N the alluvial soil contained 4,55 mg and the grey brown podsolic soil 1,64 mg nonexchangeable ¹⁵NH₄-N/100 g soil. In the alluvial soil 72% and in the grey brown podsolic soil 66% of the nonexchangeable ¹⁵NH₄⁺ had been released during the growing season when ryegrass was planted. However, without plants there was no change in the content of labelled nonexchangeable NH₄⁺ in the alluvial soil or only a slight decrease in the grey brown podsolic soil. A highly significant correlation was found between the ¹⁵NH₄-N released and the ¹⁵N uptake of ryegrass in the alluvial soil (r = 0,78⁺⁺⁺) as well as in the grey brown podsolic soil (r = 0,98⁺⁺⁺).     

Vorstellung der SrCl2-Methode nach Bach zur Bestimmung der effektiven Kationenaustauschkapazität und Vergleich mit der NH4Cl-Methode

Presentation of the SrCl₂-method after Bach for the determination of the effective cation exchange capacity and comparison with the NH₄Cl-method The SrCl₂-method for the determination of the effective cation exchange capacity CEC_eff has been developed by Dr. H. Bach, a former geochemist of the “Geologisches Landesamt Schleswig-Holstein”. Exchangeable metallic cations in soils are displaced by a 0, 1 M SrCl₂-solution and analyzed from the percolate. Reexchange of strontium by a 0, 1 M MgCl₂-solution allows to determine the CEC_eff by analyzing for strontium in the second percolate. In comparison with the customary application of NH₄Cl, SrCl₂ shows the following advantages:

• 1 The nearly unbuffered SrCl₂-solution adopts instantly the pH of the soil.
• 2 In contrast to the weakly acid NH₄Cl-solution, no H₃O⁺-cations compete with the exchange cation. Furthermore, partial dissolution of clay minerals is prevented because of the near-neutral character of the SrCl₂-solution.
• 3 The SrCl₂-method can be applied on all types of soils including carbonate- and salt-bearing soils.
• 4 The amount of free (dissolved) cations can be approximated.

     

Kinetics of 15NH4 + assimilation in tomato plants: evidence for 15NH4 + assimilation via GDH in tomato roots 1

The kinetics of ¹⁵NH₄ ⁺ assimilation into free amino acids and total reduced nitrogen were monitored in both roots and shoots of two week old tomato seedlings supplied with 5 mM 99% (¹⁵NH₄)₂SO₄ via the aerated root medium in hydroponic culture, in the presence and absence of a 2 h pre‐incubation with 1 mM methionine sulfoximine (MSX). The labeling kinetics of amino acids in roots of tomato plants in the presence of MSX show that continued assimilation of ¹⁵NH₄ ⁺ can occur when the GS/GOGAT cycle is inhibited. In the presence of MSX, three amino acids [glutamate, alanine, and y‐amino butyrate (GABA)] of the root tissue continue to become labeled with ¹⁵N under conditions where labeling of the amino‐N moiety of glutamine is completely inhibited. This indicates primary ammonia assimilation via GDH, or alternatively, assimilation of ammonia into alanine via alanine dehydrogenase. Free ammonia accumulates rapidly in both shoots and roots of tomato in response to MSX. The labeled ammonia accumulated in the roots in the presence of MSX must be largely derived from the medium whereas in shoots this ammonia appears to be derived from catabolism of unlabeled amino acids and proteins. The pools of glutamine, glutamate and alanine after 24 h exposure to ¹⁵NH₄ ⁺ were, on the average, 5‐ to 10‐fold lower in the MSX‐treated than in the control (‐MSX) shoots and roots. In contrast, the pools of valine, leucine, isoleucine, proline, threonine, phenylalanine, lysine, and tyrosine increased 5‐ to 10‐fold above the control values in the shoots of MSX‐treated plants, and 2‐ to 4‐fold above control values in the roots of MSX‐treated tomato plants after 24 h. The latter amino acids all exhibited low isotope abundance, and presumably were derived from protein turnover.     

Verhalten von Schwermetallen in Böden. 2. Extraktion mobiler Schwermetalle mittels CaCl2 und NH4NO3

Behaviour of heavy metals in soils. 2. Extraction of mobile heavy metals with CaCl₂ and NH₄NO₃ 156 soil samples from arable fields, grassland and forest stands were analysed for the CaCl₂^? and NH₄NO₃^? extractable contents of Cd, Zn, Mn, Cu and Pb. The average amounts of Cd, Zn, Cu and Pb extracted with CaCl₂ are higher compared with NH₄NO₃ whereas the relation for Mn is vice versa. The proportion of the NH₄NO₃^? extractable contents in percent of the CaCl₂^? extractable contents of Cd, Zn and Pb decrease with increasing pH, whereas the contents of Mn and Cu increase. Inspite of a differing extraction behaviour of the two salt solutions the CaCl₂^? and NH₄NO₃^? extractable amounts of Cd, Mn, Zn und Pb are highly correlated and can be converted one into another. The mobile (CaCl₂, NH₄NO₃) proportion of the corresponding total, EDTA and DTPA heavy metal contents is in close relation to the pH of the soils. Using CaCl₂ solution the threshold pH values for an increasing mobility decrease in the order Cd > Mn > Zn > Cu > Pb, using NH₄NO₃ as extractant the order is Mn > Cd > Zn > Cu > Pb. In the case of CaCl₂ as extractant soluble chloro-Cd-complexes will be formed so that the Cd mobility in soils will be overestimated in most cases.     

Nitrat‐Austräge auf intensiv und extensiv beweidetem Grünland,erfasst mittels Saugkerzen‐ und Nmin‐Beprobung II Variabilität der NO3‐ und NH4‐Werte und Aussagegenauigkeit der Messmethoden

Nitrate leaching from intensively and extensively grazed grassland measured with suction cup samplers and sampling of soil mineral‐N II Variability of NO₃ and NH₄ values and degree of accuracy of the measurement methods Data from a grazing experiment — comparison of mean values, see Anger et al. (2002) — were used to estimate within‐field variability to asses the accuracy of two frequently used methods of estimating NO₃ leaching on pastures: (1) the ceramic suction cup sampling (with 34 cups ha^—1 minimum, calculated climatic water balance, 4 leaching periods) and (2) using the soil mineral‐N method (vertical soil NO₃ and NH₄ content in 0—0.9 m (N_min) measured at the beginning and end of two winters on a minimum of 10 different areas of 50 m² each with a minimum of 7 different sample cores). These methods were used on two permanent pastures with high mean stocking density of cattle of 4.9 LU ha^—1 on 1.3 ha with N‐fertilization of 250 kg N ha^—1 (= intensive [I]) and 2.9 LU without N fertilization on a 2.2 ha pasture (= extensive [E]). The results show that NO₃ leaching on pastures was largely due to few selectively extremely high NO₃ amounts under a few excrement spots — mainly urine spots — which would not be sampled representatively with an acceptable effort in a conventional grazing experiment. In both grazing treatments, very large spatial variation occurred. This was greater between the different suction cups than between the compound mineral N samples of each area. Therefore, a marked skewness and kurtosis demonstrated a non‐normal distribution of samples from suction cups, while mineral N values did not show this effect consistently. Sampling selected mostly spots without noticeable influence of excrement, but a few samples with very high values identified evidently urine spots from summer or autumn grazing. The differences in mean coefficient of variation (CV) between the grazing treatments and estimation methods were mainly based on the stocking rate and the density of excrement spots. CV values were 131 % [I] / 242 % [E] for NO₃ leaching measured with suction cup samplers and of 71 % [I] / 116 % [E] for soil NO₃ values and 24 % [I] / 34 % [E] for soil NH₄ values in 0—0.9 m according N_min‐method. Results of the N_min method are obviously inaccurate even with a sampling intensity much greater than 70 cores ha^—1; and so making an estimation of NO₃ leaching by this method is unsatisfactory for pastures. Compared to this, the results of suction cup sampling are more convincing; but even with a tolerated deviation of ± 20 % from the empirically estimated average and with a 95 %‐confidence interval, the calculated mean minimum number of samples in our experiment should be increased to 146 and 265 suction cups ha^—1 for the intensively and extensively grazed treatments, respectively. This requirement would be prohibitive for many field experiments.     

Soil chemical properties affecting NH4+ sorption in forest soils

Fourteen European forest soils from the boreal to the mediterranean climate on different parent materials were investigated with respect to their ability to store NH₄⁺ in exchangeable form, using sorption isotherms. Distribution coefficients for NH₄⁺ sorption per unit weight of soil were in the range of 0.02 to 0.77. NH₄⁺ sorption coefficients were usually highest in the forest floor of a given soil. NH₄⁺ sorption behaviour of mineral soil horizons was correlated to soil parameters that are determined during routine soil analysis. A combination of CEC and base saturation explained up to 95% of the variability Of NH₄⁺ sorption. In the forest floors, variability in NH₄⁺ sorption could not be explained quantitatively from independent soil parameters. The affinity of the sorption sites for NH₄⁺ was the most important factor for explanation of the variability in NH₄⁺ sorption in the forest floors but was of low importance in mineral soil horizons. As NH₄⁺ exchanges predominantly base cations, susceptibility of NH₄⁺ to transport through the soil profile increases with Iowbase saturation of a soil as well as with low CEC values.     

Verteilung von Stickstoff auf Sproß und Wurzel bei jungen Bohnenpflanzen nach der Aufnahme von NO und NH

Translocation of nitrogen to the shoot of young bean plants after uptake of NO and NH by the root Phaseolus vulgaris plants (var. nana, cv. Saxa) at the primary leaf stage (without nodules) were fed during 6 hours with ¹⁵NO and ¹⁵NH, respectively. 24 hours after the absorption period more ₁₅N from the absorbed NO was translocated from the root to the shoot. The presence of NH in the nutrient solution enhanced the translocation of ¹⁵NON, probably by an inhibition of nitrate reductase. NH_4-⁺¹⁵N is mainly retained in the root by a high incorporation into the root protein. It can be concluded that nitrogen from newly absorbed NO is not retained and used for protein synthesis in the root according to the root's potential to synthesize protein. Nitrate reduction in the root is considered to be the limiting factor. This is supported by the fact that withdrawal of NO in the nutrient solution prior to the ¹⁵N-experiment increased NOtranslocation to the shoot as a consequence of a lowered level of nitrate reductase. In an experiment with ¹⁴NOsupply to the roots and ¹⁵NOapplication to the primary leaves (infiltration method) a considerable amount of ¹⁵N was translocated from the leaves to the roots. This indicates that an insufficient NOreduction in the root can be substituted by a retranslocation of reduced N-compounds from leaves to the roots. The proportion of NO reduced in the root influences also the pattern of primary distribution of nitrogen in the shoot of plants at the 4 leaf stage. At a concentration of 0,2 meq/l NO in the nutrient solution as compared to 20 meq/l NO during 10 hours a relative higher amount of ₁₅N was transported from the root to the younger, growing leaves i.e. via the phloem to metabolic sinks.     

PRB修复垃圾渗滤液污染地下水过程中NH4+ 的变化规律

实验模拟地下水修复,以被垃圾渗滤液污染地下水为研究对象,分别用沸石、无烟煤、陶粒、活性炭、炉渣、钢渣、粉煤灰、零价铁作为填充材料,设计6种可渗透反应墙（PRB）,分别为反应器1、2、3、4、5和6。分3个试验阶段对PRB技术修复污染地下水中NH4+ 变化规律进行实验模拟研究,分析了反应器NH4+ 变化原因并探讨了NH4+ 变化机理。实验结果表明：NH4+ 去除率普遍较低,含沸石反应器脱氮效果最好,也仅为49.8%,部分反应器甚至出现负值;水解酸化作用,产生一定量NH4+ 和有机酸,造成反应器出水pH值降低和填充材料NH4+ 相对去除率偏低。PRB技术治理渗滤液污染地下水具有一定可行性,但技术有待继续深入研究。     

Anthracene influence on (15NH4)2SO4 fertilization of wheat seedlings

The influence of the addition of anthracene (1 μg anthracene g^?1 soil) in N transformations following (¹⁵NH₄)₂SO₄ fertilization (200 mg N g^?1 soil) was investigated in wheat pots by quadrapole mass-spectrometry. The dry matter yield at harvesting (after 16 days) was not statistically affected (P=0.05) by anthracene addition. The total amount of N from the fertilizer taken up by wheat seedings in 16 days was 29 and 26.8% of the added N in the absence and in the presence of anthracene, respectively, but the difference was not significantly different at level P=0.05. In order to investigate more deeply the effect of anthracene on the N cycle in the soil-plant system, the first-order rate constants of N mineralization, N immobilization, nitrification and N plant uptake have been determined according to a ¹⁵N + ¹⁴N soil-plant model. The comparison of the constants showed that organic N mineralization, nitrification and plant uptake proceeded at the same rate, while a small different rate (P=0.05) was shown by N immobilization. In fact, the N immobilization constant increased from 0.14±0.012 to 0.21±0.014 day^?1 as a consequence of anthracene addition.     

白浆土NH_4~+吸附特征的影响因素

为探究白浆土对氮素的吸附规律及其影响因素,有效指导白浆土氮肥的科学施用,本研究采用平衡吸附法,研究了温度、有机质含量、振荡时间和离子强度等因素对白浆土吸附NH4+的影响,结果表明:(1)随初始NH+4浓度(0~1 000 mg/L)的增加,白浆土对其吸附量也增加,当NH+4浓度≥600 mg/L时,吸附渐趋饱和,温度升高(293~313 K)有利于该吸附反应的进行,表观热力学参数(ΔG0、ΔH0、ΔS0)的变化表明,NH+4在白浆土表面的吸附是自发、吸热且混乱度增加的过程。(2)剖面层次所引起的有机质含量递减亦会对白浆土吸附NH+4的数量有所抑制。(3)振荡时间影响白浆土吸附NH+4的动力学过程,该过程可分为起始的快速反应阶段及经过360 min后的慢速反应阶段,所选用的4个动力学方程均能较好拟合这一动态过程。应用过渡态理论所计算的活化热力学参数(ΔG≠0,ΔH≠0,ΔS≠0)表明,NH+4在白浆土上的动力学吸附过程是耗能且体系有序度增高的过程。(4)共存Na+在其不同浓度范围内对白浆土吸附NH+4的影响机制各有不同,当Na+≥0.4 mol/L时,提升其浓度有利于NH+4在白浆土上的吸附。综上所述,在较高土壤养分含量条件下,后移施用氮肥则更有利于其利用率的提升。     

NH4+-K+ co-loaded clinoptilolite as a binary fertilizer

ABSTRACT

Understanding the potential of clinoptilolite (CLI) for adsorption of NH₄⁺ and K⁺, providing appropriate fertilizer formula, and evaluation of the produced zeolitic nutrient sources (ZNSs) to meet the plant need are the main objectives of this study. Three ZNSs (NH₄⁺-saturated, K⁺-saturated and dual-purpose NH₄⁺-K⁺ saturated CLI) were produced, assessed, and compared with commercial N and K fertilizers (CFs) on corn growth in a greenhouse. The results indicated that CLI can potentially adsorb both NH₄⁺ and K⁺ to the maximum values of 25.00 mg-NH₄⁺ g^?1 and 47.61 mg-K g^?1, respectively, and chemisorptions mainly followed the process of adsorption. Saturation of zeolite by NH₄⁺ and K⁺ occurred after 10 and 15 d which lead to ZNSs with 2% and 5% of N and K, respectively. NH₄⁺-K⁺ saturated CLI contained 1% N and 1% K. The greenhouse experiment showed no significant difference between ZNSs and CFs on plant growth. However, the application of both N and K in the form of zeolitic sources significantly increased the uptake of N by the plant. The highest uptake of K (2.05 g pot^?1) occurred in plants supplied with both natural zeolite and CFs. The present results may benefit the future utilization of ZNSs in environmental friendly farming practices.     

Geomorphologische und bodengeographische analyse holozäner, Jung- und Mittelpleistozäner sedimente und böden in Spanien und Südfrankreich

Seven multisectional profiles are described, taken mainly from loess soils and loess-like sediments in Northwest Spain, Central Spain, Southeast Spain and the South of France. The silty sediment sequences all show several soil formations, developed to varying extents In addition, a terrace profile with silty surface layers (Ciempozuelos, south of Madrid) and a terrace profile with silty inter-layers (Arobes, near Ribadesella) were found. Because of their morphological situation, their strata sequence and facies, we have classified the profiles as upper and middle Pleistocene. This is based on the hypothesis that climatic variations and the resulting pedogenetic superimpositions of the sediments behaved similarly to those in Central Europe. Our chronological classifications - apart from the profile in Tapia de Casariego in NW Spain - should be understood as suggestions, which do not preclude the possibility that new findings may make revision necessary. The profile at Tapia de Casariego, however, exhibits many similar features to the Central European Würm-Eem standard profile. ¹⁴C-dates do not contradict this statement.In addition, views are expressed on the question of the origin of the loess and the medium of transport. Consideration is given to the Holocene surface soils, as well as to the climatic preconditions which come into question in the formation of paleosoils in the study area.

Zusammenfassung

Es werden sieben mehrgliedrige Profile vornehmlich in Lössen und lößartigen Sedimenten aus NW-Spanien, Zentralspanien, Südostspanien und Südfrankreich beschrieben. Die Sedimentabfolgen mit schluffigem Charakter weisen alle mehrere unterschiedlich intensiv ausgeprägte Bodenbildungen auf. Es konnte ferner ein Terrassenprofil mit schluffigen Deckschichten (Ciempozuelos südlich Madrid) sowie ein Terrassenprofil mit schluffigen Zwischenlagen (Arobes bei Ribadesella) gefunden werden. Zeitlich stufen wir die Profile aufgrund ihrer morphologischen Lage sowie ihrer Schichtenabfolge und Fazies ins Jung- und Mittelpleistozän ein. Dabei gehen wir von der Basishypothese aus, daß sich in Südfrankreich und Spanien die Klimaschwankungen und die auf sie zurückzuführenden pedogenetischen Überprägungen der Sedimente ähnlich verhalten haben wie in Mitteleuropa. Unsere zeitlichen Einstufungen sind - vom Profil in Tapia de Casariego in Nordwestspanien abgesehen - als ein Datierungs-Vorschlag zu verstehen, was nicht ausschließt, daß bei weiter fortgeschrittenem Kenntnisstand eine Umdeutung vorzunehmen ist. Das Profil von Tapia de Casariego weist allerdings große Gemeinsamkeiten mit dem mitteleuropäischen Würm-Eem-Standardprofil auf. ¹⁴C-Daten sprechen nicht gegen diese Aussage. Ferner wird zur Lößherkunft und zum Transportmedium Stellung genommen. Die holozänen Oberflächenböden finden ebenso Beachtung wie die klimatischen Voraussetzungen, die bei der Ausbildung von Paläoböden im Bearbeitungsgebiet in Betracht kommen.