Elektrophoretische Blutuntersuchungen bei normalen und bauch wassersuchtkranken Karpfen

Ohne Zusammenfassung Vorliegende Untersuchungen wurden mit Mitteln und mit Unterstützung des Bundesministeriums für Ern?hrung, Landwirtschaft und Forsten, Bonn, durchgeführt, wofür auch an dieser Stelle noch einmal unser verbindlichster Dank ausgesprochen sei.     

Moisture transport and intraseasonal variability in the South America monsoon system

This paper examines moisture transport on intraseasonal timescales over the continent and over the South Atlantic convergence zone (SACZ) during the South America (SA) summer monsoon. Combined Empirical Orthogonal Function analysis (EOFc) of Global Precipitation Climatology Project pentad precipitation, specific humidity, air temperature, zonal and meridional winds at 850?hPa (NCEP/NCAR reanalysis) are performed to identify the large-scale variability of the South America monsoon system and the SACZ. The first EOFc was used as a large-scale index for the South American monsoon (LISAM), whereas the second EOFc characterized the SACZ. LISAM (SACZ) index showed spectral variance on 30?C90 (15?C20) days and were both band filtered (10?C100?days). Intraseasonal wet anomalies were defined when LISAM and SACZ anomalies were above the 75th percentile of their respective distribution. LISAM and SACZ wet events were examined independently of each other and when they occur simultaneously. LISAM wet events were observed with the amplification of wave activity in the Northern Hemisphere and the enhancement of northwesterly cross-equatorial moisture transport over tropical continental SA. Enhanced SACZ was observed with moisture transport from the extratropics of the Southern Hemisphere. Simultaneous LISAM and SACZ wet events are associated with cross-equatorial moisture transport along with moisture transport from Subtropical Southwestern Atlantic.     

Sustainable Soil Particle Size Characterization Through Image Analysis

A rapid, clean, low-energy, image-based method for determining the grain size distribution of soils by image analysis has been developed. The method is called Sediment Imaging or “Sedimaging”. It develops the grain size distribution for particles in the range between a U.S. Standard Sieve No. 10 (2.0 mm openings) and U.S. Standard Sieve No. 200 (0.075 mm openings) range. The system utilizes a high resolution Nikon D7000 digital single lens reflex camera and image processing software developed specifically for interpreting the images and producing the resulting grain size distribution. The Sedimaging system is more sustainable and environmentally friendly than traditional sieving by virtue of its far lower power needs, less water consumption, longer equipment life and less maintenance. From the environmental and health perspectives, Sedimaging is less noisy, generates no vibrations and produces no airborne particulates. Sedimaging is also significantly faster than sieving and produces thousands of data points compared to typically 8 by sieving; it also automatically computes grain size distribution metrics such as the coefficients of uniformity and gradation.     

Influence of the Madden Julian Oscillation on precipitation and surface air temperature in South America

The regional influence of the Madden–Julian oscillation (MJO) on South America is described. Maps of probability of weekly-averaged rainfall exceeding the upper tercile were computed for all seasons and related statistically with the phase of the MJO as characterized by the Wheeler–Hendon real-time multivariate MJO (RMM) index and with the OLR MJO Index. The accompanying surface air temperature and circulation anomalies were also calculated. The influence of the MJO on regional scales along with their marked seasonal variations was documented. During December–February when the South American monsoon system is active, chances of enhanced rainfall are observed in southeastern South America (SESA) region mainly during RMM phases 3 and 4, accompanied by cold anomalies in the extratropics, while enhanced rainfall in the South Atlantic Convergence Zone (SACZ) region is observed in phases 8 and 1. The SESA (SACZ) signal is characterized by upper-level convergence (divergence) over tropical South America and a cyclonic (anticyclonic) anomaly near the southern tip of the continent. Impacts during March–May are similar, but attenuated in the extratropics. Conversely, in June–November, reduced rainfall and cold anomalies are observed near the coast of the SACZ region during phases 4 and 5, favored by upper-level convergence over tropical South America and an anticyclonic anomaly over southern South America. In September–November, enhanced rainfall and upper-level divergence are observed in the SACZ region during phases 7 and 8. These signals are generated primarily through the propagation of Rossby wave energy generated in the region of anomalous heating associated with the MJO.     

Effects of in-situ conditions on relative permeability characteristics of CO2-brine systems

Carbon dioxide capture and geological storage (CCGS) is an emerging technology that is increasingly being considered for reducing greenhouse gas emissions to the atmosphere. Deep saline aquifers provide a very large capacity for CO₂ storage and, unlike hydrocarbon reservoirs and coal beds, are immediately accessible and are found in all sedimentary basins. Proper understanding of the displacement character of CO₂-brine systems at in-situ conditions is essential in ascertaining CO₂ injectivity, migration and trapping in the pore space as a residual gas or supercritical fluid, and in assessing the suitability and safety of prospective CO₂ storage sites. Because of lack of published data, the authors conducted a program of measuring the relative permeability and other displacement characteristics of CO₂-brine systems for sandstone, carbonate and shale formations in central Alberta in western Canada. The tested formations are representative of the in-situ characteristics of deep saline aquifers in compacted on-shore North American sedimentary basins. The results show that the capillary pressure, interfacial tension, relative permeability and other displacements characteristics of CO₂-brine systems depend on the in-situ conditions of pressure, temperature and water salinity, and on the pore size distribution of the sedimentary rock. This paper presents a synthesis and interpretation of the results.     

Variations in eelgrass (<Emphasis Type="Italic">Zostera marina</Emphasis> L.) morphology and internal nutrient composition as influenced by increased temperature and water column nitrate

In an experimental mesocosm system, we evaluated changes in morphology and tissue nutrient content (carbon [C], nitrogen [N], phosphorus [P]) of eelgrass (Zostera marina L.) as influenced by increased temperature and nitrate. During the late summer-fall growing season (14 weeks, August through mid-November), control plants were compared to plants grown at elevated temperatures (3°C to 4°C above ambient, based on 20-yr weekly means) and elevated water column nitrate enrichment (8 μM NO₃ ⁻, pulsed daily). Both increased temperature and increased nitrate led to declines in shoot density (by 40% and 48% for nitrate and temperature treatments, respectively), as well as decreased leaf and root production. High temperature promoted increased total C content of leaf tissues, whereas high nitrate increased the percentage of N in belowground tissues and depressed the C∶N ratio in aboveground tissues. The data indicated that increases in nitrate or temperature can significantly reduce the size ofZ. marine shoots and can also alter the internal C and N content. This reduction was not associated with significant increases in light-attenuating algae as we controlled epiphytic growth, so we suggest that a direct physiological mechanism or other mechanism was involved.     

Upper-air wave trains over the Pacific Ocean and wintertime cold surges in tropical-subtropical South America leading to Freezes in Southern and Southeastern Brazil

Summary ?An examination is made of the relationships between circulation and convection over South America as related to strong cooling in southern and southeastern Brazil during austral wintertime. Correlations between sub monthly (2–30 days) near-surface air temperature in southeastern Brazil reveal the preferred path of a quasi-stationary Rossby wave impinging on to the region from mid-latitudes and emanating from the tropical western Pacific. The large amplitude upper-level trough in middle latitudes, which extends into the tropics, has been pointed out as one of the major features of the cold situation. These waves embedded in westerly flow are an example of wintertime tropical-extratropical interactions leading to cooling in southeastern South America. This is suggested by the results from the observational and baroclinic-modeling studies presented here. However, in addition to the right synoptic situation associated with this intermediate modulation, local controls are important on determining the degree of cooling and the occurrence of freezes. Received August 25, 2000; revised September 1, 2001; accepted December 1, 2001