Periglacial cover-beds on the Swiss Plateau: indicators of soil, climate and landscape evolution during the Late Quaternary

Soils and the stratification of their parent materials were studied on the central Swiss Plateau. This area is characterized by glacial deposits varying from Late Glacial to pre-Würmian in age. Soils of all studied sites are developed within colluvial layers, the so-called cover-beds. In relation to the underlying deposits, we find a regular spatial distribution of cover-bed types. A surficial layer (Upper Layer) with relatively constant thickness (around 50 cm independent of relief position) covers Pleistocene sediments of any age. Therefore, it was formed mainly by cryoturbation/solifluction after the final glacier retreat from the Swiss Plateau (Younger Dryas or Oldest Dryas age). Layers that originate mainly from aeolian processes (Intermediate Layers) are restricted to areas outside the recessional moraines of the Berne-Stade (BS). Hence, they were formed merely up to the late Pleniglacial. They frequently consist of two distinct layers. Outside the glaciation of the Last Glacial Maximum (LGM), cover-beds in places overlie pre-LGM palaeosol relics (probably of Eemian age or even older). These are preserved even on higher relief positions, indicating that periglacial erosion during the Pleniglacial was only marginal. The palaeosol relics also occur on till of the so-called Older Wangen-Stade, which is commonly believed to represent the LGM, whereas we consider it to be older at least partly. Eventually, the distribution of soil types and their ecological characteristics are influenced considerably by cover-beds. As these beds reflect distinct phases of the Pleistocene, colluvial sediments provide a major tool for linking modern landscape characteristics to the Late Quaternary climate evolution.     

Zum Vergleich von Penetrometermessungen,durchgeführt bei unterschiedlichem Wassergehalt

Penetrometer measurements at different soil water contents With use of a large number of field measurements an empirical relation between soil water content and penetrometer resistance was derived. For this purpose the soils were subdivided with respect to their texture and bulk density. The derived relations enable a comparison of penetrometer values derived at different soil water content.     

Prevalence pattern and biology of Sarcocystis capracanis infection in the Egyptian goats: a light and ultrastructural study

Cysts of Sarcocystis capracanis obtained from infected goats were examined to clarify the effect of the parasite on the host. Muscle tissues from fresh oesophagus, tongue, diaphragm and skeletal muscles of 680 goats were slaughtered in the main abattoir of Cairo, Egypt and they were examined microscopically for Sarcocystis infection for the first time in Egypt. 540 out of 680 (79.4%) of examined goats were found to be infected with Sarcocystis sp. The infection was recorded firstly by light microscopy as spindle shaped cysts embedded in the muscle tissues. The validity of this species as S. capracanis was confirmed by means of ultrastructural characteristics of the primary cyst wall which revealed the presence of thick-radially striated wall with finger like projections, underlined by a thick layer of ground substance enclosing the developing metrocytes and merozoites that usually contain nearly all the structures of the apical complex and fill the interior cavity of the cyst. The cyst cavity is divided by many septa extending from the ground substance and producing large number of chambers. An experimental infection using the highly infected muscles was carried out to determine the final host, which is dog. Smears of intestinal epithelium were taken to examine the endogenous stages (gamogony and sporogony) by means of light microscopy. These stages were mainly observed as to infect the lamina propria of the posterior third of the small intestine. Gamogony and zygote formation (fertilization) occurred 2-8 days post infection, while sporulation took place within the final host 13-15 days and sporocysts were passed within faeces of the infected puppies at that time. The prepatent period of S. capracanis was 12-15 days, while the patent period was extended to 37 days. In goats, infection with S. capracanis led to the loss of weight, anaemia, abortion and even death in cases of heavy infection. While bleeding, watery faeces filled with mucous on 5th and 8th day p.i. as well as intestinal lesions are the pathogenic effects occurred in puppies after experimental infection.     

Contribution of different rumen microbial groups to gas,short‐chain fatty acid and ammonium production from different diets—an approach in an in vitro fermentation system

In this study, the relative contribution of different microbial groups to ruminal metabolism was investigated for different diets. The rumen microbial cultures included whole rumen fluid, fungi + protozoa, bacteria + protozoa, protozoa and bacteria + fungi and were established by physical and chemical methods. Gas production, short‐chain fatty acid (SCFA) and ammonium production were measured at 24 hr in in vitro incubations using the Hohenheim gas test (HGT) procedure. Seven donor animal diets with different concentrate‐to‐roughage ratios (C:R: 10:90, 30:70, 50:50, 70:30, 70:30BC (BC = NaHCO₃), 90:10 and 90:10BC) and five HGT diets (C:R: 10:90, 30:70, 50:50, 70:30 and 90:10) were formulated. Incubations in the HGT were always based on inoculum from sheep diets with the respective C:R ratio. Gas and ammonium production increased (p < 0.001) as a result of a gradual increase in concentrate proportion of the diets. In general, SCFA production followed the same trend. Whole rumen fluid and bacteria + fungi produced approximately 50% higher gas volume than protozoa and fungi + protozoa fractions, whereas gas production with bacteria + protozoa was at an intermediate level. Coculture of protozoa either with bacteria or with fungi produced more ammonium. Populations without bacteria were characterized by a particularly high acetate/propionate ratio. Although an interaction between microbial group and diet was observed for several variables, no clear direction could be established. Manipulating rumen fluid by selectively suppressing specific rumen microbial groups may be a helpful tool in elucidating their role in nutrient degradation and turnover in vitro.     

Composting of Wood Containing Polycyclic Aromatic Hydrocarbons (PAHs)

The addition of various nitrogen sources, such as liquid hog manure and mineral medium, to pine wood accelerated the composting process in Dewar vessels, which was obvious from the increased decomposition temperature and the more intensive oxygen consumption and carbon dioxide production. During composting in Dewar vessels of artificially PAH-contaminated pine wood soaked with liquid manure, the PAH degradation was influenced by the inoculum used. The fastest PAH degradation was achieved by compost addition, but the most intensive carbon dioxide evolution was measured with hydrocarbon-polluted soil as an additive. After 61 days, the PAH content of the wood was reduced from each 1000 mg/kg to 26 mg/kg of phenanthrene and 83 mg/kg of pyrene. The relation between the microbial wood decay and PAH degradation shows that the detoxification at least of artificially PAH-polluted wood demands only a partial wood decay.

A pilot scale percolator was applied to composting of artificially contaminated pine wood and really polluted waste wood. After 27 days of remediation, the portion of residual PAHs was higher in the case of the really polluted material. The slower degradation in the real waste wood may be explained by the lower bioavailability of pollutants in comparison with the artificially contaminated wood. In really polluted wood, the degradation rate of PAHs depended on their degree of condensation (the higher the number of aromatic rings the smaller the degradation rate was).     

Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) in Waste Wood

PAH-contaminated waste wood is a serious environmental problem. As an alternative to incineration and landfill disposal, wood containing PAHs may be detoxified by composting. The efficiency of this process depends on the composting conditions. The aerobic treatment of PAH-containing wood was therefore investigated under varying environmental conditions with particular attention to the kinetics of PAH degradation and wood mineralization. The composting of pine wood spiked with 2 g/kg phenanthrene, anthracene and pyrene each and subsequently artificially aged was studied on a laboratory-scale using a respiration analyzer. The temperature was found to highly influence both PAH degradation and wood decay. The fastest and most extensive PAH degradation and wood mineralization were found at 30°C. Higher temperatures particularly inhibited the degradation of anthracene and pyrene. The addition of urea markedly accelerated both PAH degradation and wood mineralization. Only small amounts of urea were needed to maximize PAH degradation, whereas higher amounts of urea were required to maximize wood mineralization. Urea hydrolyzes to ammonium carbonate, which in turn forms highly volatile ammonia. When more then 2 g/kg urea-N was added to the wood, excessive nitrogen disappeared as ammonia via the gas phase. Using nitrate instead of urea dramatically reduced both PAH degradation and wood mineralization. Although a slightly alkaline pH seemed to promote PAH degradation, it has to be taken into account that this experiment was carried out with nitrate as an N source rather than urea to avoid any N losses at high pH values. Glucose as a cosubstrate neither accelerated PAH degradation nor stimulated wood decay. Molasses as a cosubstrate actually inhibited PAH degradation since it contains much salt and alkalinized the rot material.     

Prazisionsstufen der Stickstoffdüngungsbemessung zu Winterweizen und Winterroggen auf Sandigen Böden*

In einer Versuchsserie von 1996 bis 1998 wurden auf vier sandigen Standorten Feldversuche mit Winterweizen bzw. Winterroggen durchgeführt. In die Parzellen sind Mikroparzellen für die Düngung mit ¹⁵N‐Tracern installiert worden. Varianten: ungedüngt, halbierte Düngung, 120kgha^?1 ? in 2 bzw. 3 Teilgaben sowie Düngerberechnung über ein EDV‐Programm unter Einbeziehung des N_min‐Gehaltes des Bodens und schließlich zuzüglich der indirekten Messung des Chlorophyllgehaltes der Blätter des Getreides.

Die über Computer. N_min‐Ermittlung und Chlorophyll‐Tester modifizierten N‐Aufwendungen haben zu keiner eindeutigen Ertragsverbesserung geführt. Insgesamt wurden zwischen Ertrag und N_min‐Werte + N‐Düngung enge Beziehungen errechnet. Die Spanne der N‐Entzüge ist von 41 bis 160 kgha^?1 bei Weizen und 48 bis 83 kg ha^?1bei Roggen weit. Der N_min‐Gehalt zum Erntezeitpunkt ist unterschiedlich. Je niedriger die Rest‐N‐Mengen sind, um so mehr verringert sich der prozentuale Anteil des düngerbürtigen ? bzw. die Wiederfindungsrate des eingesetzten Mineraldüngers.     

Soil indicator systems ‐ the basis for soil conservation decisions to control soil erosion and soil compaction

The efficiency and acceptance for erosion and compaction control management is not high and therefore not a guarantee for sustainable land use and soil functionality. The best method for increasing acceptance is a regional soil indicator system combined with an environmental indicator system (McRae et al. 2000). Like the concept of “critical load inputs”; for chemical pollutants, this system would make it possible to quantify the soil state and soil condition for decisions concerning the soil carrying or load capacity. The next step is the assessment of the land use pressure on soil in terms of the soil load capacity and the driving forces for land use. These results may determine the response level required: In a balanced situation, Best Management Practices may help ensure sustainability is maintained, slightly disproportional results suggest additional special agricultural management techniques may be needed, while significant differences may indicate the need for additional land use adjustments or changes in technical management. The indicator system is ideal for application in north‐eastern Germany for all moraine areas and the areas at risk to water and wind erosion and soil compaction.