bluuebunny/crossref_metadata_2025 huggingface dataset:
Interannual variability of some trace elements and surface aerosol
Authors: Kane R. P.
Published: February 2007

After correcting for seasonal variations and long‐term (linear or quadratic) trends, the residual interannual anomalies (variations) of the trace elements and surface aerosol show periodicities in the Quasi‐biennial Oscillation (2–3 years) and 3–5 years range. Quasi‐biennial Oscillations (QBO) of some elements match with the QBO of equatorial 50‐hPa wind, but for some others, matching is not good. For some elements, matching with Southern Oscillation index is good. The relationship is probably through the sea‐surface temperature changes, which affect the role of the ocean as a source/sink for these trace elements. Interaction between equatorial wind QBO and extratropical phenomena should also be involved.
Intensity and form of the urban heat island in barcelona
Authors: Moreno‐garcia M. Carmen
Published: February 2007

A statistical analysis of the differences between the daily minima in the centre of Barcelona and those of the airport, supplemented by temperature readings taken along a number of transects through the urban area, have revealed the intensity of the heat island effect, which reaches a maximum intensity of 8°C. It was also possible to plot the spatial configuration of the latter.
Relationship of new zealand daily and monthly weather patterns to synoptic weather types
Authors: Kidson John W.
Published: February 2007

The effectiveness of the classification of daily mean sea‐level pressure patterns over New Zealand into 13 synoptic types by Kidson (1994) has been tested through their relationship with daily and monthly variations in temperature, precipitation, sunshine, and daily wind run over the period 1980–1990.

The mean anomalies of these weather elements for each synoptic class often showed spatially consistent patterns, with departures falling in the second and fourth (below normal and above normal) quintiles. These were readily interpretable in terms of the effects of advection, differences in static stability, and the influence of mountain ranges on the low‐level circulation.

On a monthly basis, 60 per cent of the variance in the frequencies of occurrence of the 13 synoptic types was found to be due to three significant EOFs. These formed the basis of an iterative clustering process to group the flow patterns for the 11‐year period into eight sets of monthly analogues or “regimes”, for which the composite patterns of the weather element were obtained.

Overall, the results suggest that the synoptic classifications are likely to be helpful in specifying daily values of weather elements, and in interpreting the monthly departures of the New Zealand climate. They should also prove useful in validating climate model performance for the New Zealand region and in providing better detail of the regional climate changes likely to result from the greenhouse effect.
Correlation of solar radiation with climatological data for port harcourt, nigeria
Authors: Kuye Ayoade , Jagtap S. S.
Published: February 2007

A total of 42 different empirical model equations for estimating global insolation from other meteorological parameters is discussed and their predictions compared with measured values for Port Harcourt. The parameters are sunshine hours, relative humidity, temperature as well as geographical declination, latitude and altitude. It is found that a number of the models give significantly the same level of prediction. The average error in the calculated insolation being between 1.7 and 2.6 per cent (maximum deviation less than 7 per cent) when 8‐year monthly average data are used. Utilizing the individual monthly average or daily average data resulted in higher errors in the range 6–7 per cent (maximum deviation less than 33 per cent).
Modelling and forecasting seasonal precipitation in Florida: A vector time‐domain approach
Authors: Chu Pao‐Shin , Katz Richard W. , Ding Ping
Published: February 2007

Some major stages of vector autoregressive (AR) modelling consisting of specification, order determination, estimation, diagnostic checking, and forecasting are described. To illustrate the utility of multivariate AR models for climate teleconnection research, the seasonal Southern Oscillation Index (SOI) and a precipitation index in Florida are modelled jointly. Two bivariate AR processes, order one and order four, are selected as candidate models to represent the joint series.

To make a comparison of model performance, one‐season‐ahead forecasts of Florida precipitation are generated from the bivariate AR models, as well as from a simple regression model, for recent years that are independent from the period on which the model is constructed. Results show that seasonal forecasts from the two‐dimensional, order‐one model are somewhat better than the other two models. One new and important finding of this study is that, in addition to winter precipitation forecast skill, there is also a forecast skill for autumn precipitation. The physical mechanisms by which these teleconnections might arise are briefly discussed. Other applications of vector models are suggested.
Modelling evaporation from a high subarctic willow‐birch forest
Authors: Blanken Peter D. , Rouse Wayne R.
Published: February 2007

Continuous measurements of the energy balance were made during the 1991 growing season over a dwarf willow‐birch forest located near Churchill, Manitoba. Intensive measurements of stomatal conductance for several species were taken on three fair‐weather days. These represented a wide range of air temperatures and leaf‐to‐air vapour pressure deficits and allowed the quantification of the surface‐atmosphere interaction. Modelling evaporation on a 0‐5 h basis can be performed accurately using a modified version of the Penman‐Monteith combination model coupled to a submodel of stomatal conductance. With a vegetated surface cover of about 90 per cent at full leafing, vegetation plays an important role in the overall moisture flux because 80 per cent is a result of transpiration. Simulating various vegetation‐change scenarios shows that species composition, through differences in stomatal behaviour, has a marked effect on evaporation.
The estimation of thermal atmospheric radiation under cloudy conditions
Authors: Alados‐Arboledas L. , Vida J. , Olmo F. J.
Published: February 2007

Among the surface radiation budget components that are needed to understand the climate of the Earth, the thermal atmospheric radiation component is the only one that is not measured routinely, so it must be estimated indirectly. The presence of clouds substantially hampers this task, supplementing the emission of water vapour and carbon dioxide in the lower atmosphere. The methods proposed to estimate thermal atmospheric radiation often rely on a cloudless sky model and a corrective term that takes into account the cloud contribution. Several models for estimating the thermal atmospheric radiation under cloudy conditions have been tested using measurements recorded in Granada (Spain) during a period of 2 years. The cloudless sky model provides estimation with an error of about 5 per cent, whereas the cloudy skies models, after some modifications, estimate thermal atmospheric radiation with an error of about 6 per cent. Our results show the convenience of a quadratic dependence on cloud amount for cloudy skies models. In addition to this, it seems convenient to use available information about the radiative properties of clouds to assign different cloud emittances for different types of clouds within each level, especially for middle level clouds.
Regionalization of Botswana rainfall during the 1980s using principal component analysis
Authors: van Regenmortel G.
Published: February 2007

A regionalization of decadal rainfall for Botswana is presented. Situated on the southern African plateau, this subtropical country offers little physiographical variation on which geographical subdivision can be based. Following similar studies a varimax rotated principal component analysis was selected as the regionalization method. Nine years of rainfall (1980–1988) for 49 stations were analysed. Component loading fields, and hence regions, are interpreted in terms of the varying influence of synoptic configurations on the various parts of the country. The first component, explaining about half of the total variance, is found to be associated with the dominant position of the surface trough in summer, with which most rainfall in Botswana is associated. The other components are interpreted as variations of this primary synoptic pattern.
The distribution and transport of atmospheric water vapour over the Arctic Basin
Authors: Serreze Mark C. , Rehder Mark C. , Barry Roger G. , Kahl Jonathan D. , Zaitseva Nina A.
Published: February 2007

A comprehensive rawinsonde archive, comprising atmospheric soundings from fixed stations, ships, and the former Soviet Union ‘North Pole’ series of drifting ice stations, is used to examine features of the distribution and transport of Arctic water vapour. Results are based on analysis of climatological, gridded seasonal and monthly fields north of 65°N of precipitable water, vertically integrated vapour fluxes, and profiles of specific humidity, vapour fluxes, temperature, and winds, compiled from objective interpolation of the quality controlled soundings. Emphasis is placed on contrasting conditions for winter and summer, with due attention paid to the potential effects of uncertainties in the rawinsonde humidity data.

For zonal means, specific humidity for all seasons typically displays a surface maximum, decreasing poleward at all levels. Precipitable water (surface‐300 hPa), has winter values ranging from 3.8 mm for 65°−70°N and 1.8 mm for 80°–90°N, with annual maxima in July of 18.2 and 12.5 mm, respectively. These zonal means, however, mask large spatial variations; precipitable water for winter, spring, and autumn shows a marked equatorward increase towards the Atlantic side of the Arctic only. Minima are found over north‐east Canada during spring, summer, and autumn.

Vapour fluxes tend to peak in the lower troposphere at about 850 hPa in winter, but over a broader layer in summer. During winter, the largest vertically integrated (surface‐300 hPa) zonal and meridional vapour transports are found between Iceland and Scandinavia. The Beaufort Sea and western Canada are the only regions where vertically integrated meridional fluxes are equatorward. During summer, the vertically integrated total flux (zonal plus meridional components) increases sharply over the Beaufort Sea. Equatorward meridional fluxes are again found over western Canada, with strong poleward meridional transports over the Atlantic sector.
Early instrumental weather data from Cadiz: A study of late eighteenth and early nineteenth century records
Authors: Wheeler Dennis
Published: February 2007

This paper examines some of the oldest instrumental records in Spain. They cover the period 1789 to 1816 for the Cádiz region and reveal strong evidence of a significant and approximately quantifiable degree of warming since those times. In contrast to the middle latitudes, greater temperature increases have occurred during the summer months. Wind records also indicate that the general circulation may have been more meridional than today.
Signals in atmospheric pressure variations from 2 to ca. 70 months: Part I, simulations by two coupled ocean—atmosphere GCMs
Authors: Hameed Sultan , Currie Robert G. , Lagrone Howard
Published: February 2007

The Fourier transform of daily averaged solar flux at the top of the atmosphere shows that the spectrum is discrete at all latitudes with lines at 12, 6, 4, 3, 2·4, 2 months, etc., which follows from the orbital characteristics of the Earth. Application of the Fourier transform to over 6000 monthly air pressure series simulated by two different versions of the Oregon State University (OSU) general circulation model (OSU‐GCM) shows the same structure, and world‐wide the mean contributions of 12, 6, and 4·2 month signals to total variance are 40, 10, and 4 percent, respectively. The Fourier spectra also yield significant subharmonic peaks, with periods T1 ≃ 40 and T2 ≃ 26 months, the quasi‐triennial (QTO) and quasi‐ biennial (QBO) oscillations, and with a period T3 ≃ 14 months, the atmospheric pole tide (APT). The spectra also yield evidence for a further 33 significant peaks, which can be explained as summation and difference tones caused by interaction of the annual and its five harmonics (first set of parents) with the subharmonics Ti, i = 1 to 3 (second parents), and the expression for the tones is

cycles per month (cpm), where j = 0,…5. The only requirement physically for these interactions is that the atmosphere be weakly non‐linear, a requirement now obviated by a simplified atmospheric model of O'Brien and Currie. World‐wide, the contribution to total variance of the 33 tones and three subharmonics is 26·8 per cent, whereas the contribution of noise is 19·4 per cent. The root‐mean‐square (RMS) errors between observations of the 33 frequencies, and between those predicted by the above equation, in the two OSU‐GCM simulations are 0·0015 and 0·0010 cpm, respectively. The two sets of parents and 33 tones vary in period from 2 to ca. 70 months and demonstrate that the spectrum of climate on these time‐scales is ‘signal‐like’ rather than ‘noise‐like’ as traditionally believed.
Prediction of annual tropical cyclone activity over the western North Pacific and the South China Sea
Authors: Chan Johnny C. L.
Published: February 2007

This study investigates the relationship between the spatial distribution of sea‐surface temperature (SST) and the annual tropical cyclone (TC) activity over the western North Pacific and the South China Sea. Monthly distributions of SST are represented by a set of empirical orthogonal functions (EOFs). The principal components (PCs) of the monthly SST associated with these EOFs are then correlated statistically with the annual number of TCs occurring over (i) the western North Pacific and (ii) the South China Sea using a forward stepwise linear multiple regression scheme.

It is found that four PCs of the monthly SST distribution together explain 89 per cent of the total variance of the annual number of TCs over the western North Pacific. Predictions of this number from both the dependent and independent (simulated using the jack‐knife method) samples have errors of less than half a standard deviation of the actual number. Two of these PCs are from the September SST, whereas the other two are from May and June SSTs. If only the latter two PCs are used, the accuracies of the prediction are slightly reduced. Therefore, a preliminary prediction can be made using these two PCs and a modified prediction can be performed at the end of September.

Two PCs are found to correlate significantly with annual TC activity over the South China Sea, representing the SST distribution in May and July. Predictions using these two PCs also give very reasonable results for both the dependent and independent samples.
Temperature trends and change points in the northern Spanish Plateau during the last 100 years
Authors: Esteban‐Parra M. J. , Rodrigo F. S. , Castro‐Díez Y.
Published: February 2007

In this work we have analysed the mean, maximum, and minimum temperature records of five localities in the northern Spanish Plateau during the last century. We have used the short‐cut Bartlett test to examine their homogeneity. Our main proposal is the detection of trends and abrupt changes, using the Mann‐Kendall test and the estimation of the magnitude of these. We have found that the minimum and mean temperatures have increased. The maxima do not present special behaviour. So the minimum temperatures show more influence over the mean temperatures than the others. Briefly, we have studied the possible linkage between the increase of minimum temperatures and urban growth in the area studied.
Fuzzy rule‐based classification of atmospheric circulation patterns
Authors: Bardossy Andras , Duckstein Lucien , Bogardi Istvan
Published: February 2007

A fuzzy rule‐based methodology is applied to the problem of classifying daily atmospheric circulation patterns (CP). The purpose of the approach is to produce a semi‐automated classification that combines the expert knowledge of the meteorologist and the speed and objectivity of the computer. Rules are defined corresponding to the geographical location of pressure anomalies. A CP is described by the location of four different possible pressure anomalies. The rules are formulated with fuzzy sets, allowing a certain flexibility because slightly different pressure maps may correspond to a given CP. Accordingly the degree of fulfilment of a rule is defined in order to measure the extent to which a pressure map may indeed belong to a CP type. As an output of the analysis, the CP on any given day is assigned to one, and only one, CP type to a varying degree of credibility.

The methodology is applied to a European case study. The subjective classification of European CPs given by Hess and Brezowsky provides a basis for constructing the rules. The classification obtained can be used, for example, to simulate local precipitation conditioned on the 700 hPa pressure field. The information content of the fuzzy classification as measured by precipitation‐related indices is similar to that of existing subjective classifications. The fuzzy rule‐based approach thus has potential to be applicable to the classification of GCM produced daily CPs for the purpose of predicting the effect of climate change on space‐time precipitation over areas where only a rudimentary classification exists or where none at all exists.
Surface aggregation and subgrid‐scale climate
Authors: Klink Katherine
Published: February 2007

Land‐surface representations used by the climate modelling community characterize locally heterogeneous surfaces as larger, homogeneous units. This loss of detail in land‐surface properties has prompted research into methods by which subgrid‐scale properties may be included within global climate models (GCMs). Coupling a regional model within a GCM represents one possible approach to resolving subgrid‐scale heterogeneity, but this method is computationally demanding. For use at global scales, two aggregation schemes have been proposed in the literature. The first assigns to each GCM grid‐cell the area‐weighted values of structural and physiological parameters typical of each subgrid surface type; the second computes separate energy balances for each surface type within the cell, then averages their responses based on areal coverage. Neither of these aggregation schemes, however, account for subgrid surface‐atmosphere interaction, surface geography, or advective effects.

This study examines climate sensitivity to methods of surface aggregation by comparing climates simulated using a three‐dimensional, mesoscale atmosphere‐land‐surface model with those produced by parameter‐based (‘averaged geography’) and energy‐balance‐based (‘mosaic geography’) aggregation schemes. Simulations are carried out for a 240 kmx240 km area using three land‐surface configurations. Each domain contains a small area of bare soil, along with varying amounts of grass and coniferous trees.

Model comparisons indicate that the averaged geography scheme tends to overestimate the latent and sensible heat flux from the model domain, and to yield surface temperatures that are cooler (by as much as 1.8°C) than control‐simulated values. Mosaic geography results are more similar to control climates, but tend to underestimate surface sensible heat flux and to overestimate the latent heat flux. Surface temperatures produced by mosaic runs are warmer than control values by up to 0.8°C. Overall, the mosaic aggregation scheme appears superior to the averaged geography method in its ability to capture the domain‐averaged climatic effects of subgrid heterogeneity. However, relatively large differences between the climates simulated by mosaic and control experiments for the individual grass, coniferous tree, and bare soil areas suggest that studies of subgrid climatic forcing and response are best performed with regional‐scale or coupled regional‐global climate models.
Rainfall variability associated with Lamb weather types: The case for incorporating weather fronts
Authors: Wilby R. L. , Barnsley N. , O'Hare G.
Published: February 2007

The value of weather generators for down‐scaling the output of general circulation models for regional impact assessments is limited by the assumption of stationary‐rainfall‐circulation‐pattern relationships. This note assesses the potential of incorporating weather front data into existing stochastic precipitation models to describe intraweather pattern rainfall variability.
Erfahrungen mit dem verbesserten Gerät zur Korngrößenbestimmung nach der Pipettmethode von Köhn
Authors: Goetz D.
Published: February 2007

Experiences with a new automatic apparaturs for mechanical analysis of soils

A commercial instrument for mechanical analysis of soil was improved technically.
Geologisch‐archäologische Untersuchungen zu den Entstehungsbedingungen der Marschen in Nordfriesland
Authors: Prange Werner
Published: February 2007

Geological and archaeological investigation of the mode of origin of the marshes in Nordfriesland (Germany)

In the bogs between marine sediments and Pleistocene uplands on the mainland of Nordfriesland, saltbearing peat for salt production was dug before, as well as while, the bogs were covered by sediments with high clay content. Additionally, there is not much fresh‐water coming from the Pleistocene uplands and carbonate is only preserved in the “Klei” deposited in the resulting holes. These facts show, that the “Klei” was originally calcareous and that it was deposited in water with a high salt content. Therefore one cannot conclude that adsorbed cations and narrow Ca:Mgratio (0.5–1.5) indicate sedimentation in brackish water and deposition of sediments with a low, or indeed, no carbonate content. Hence adsorbed cations and the Ca:Mgratio do not allow the separation of marsh soils from soils of a marine or brackish origin.
Die Bleikontamination von Pflanzen und Böden durch Kraftfahrzeugabgase
Authors: Sommer G. , Rosopulo A. , Klee J.
Published: February 2007

Lead Contamination of Plants and Soils Caused by Automobile Exhaust Gases

The examination of grassland, wheat, maize and potatoes has shown that the lead content of plants in the vicinity of roads rises with increasing traffic intensity and falls with increasing distance from a motorroad. An increase in the coating of lead is observable up to a distance of 50 m from an autobahn. A roadside sample of grass from the Munich–Stuttgart autobahn was found to contain 470 mg lead/kg dry matter. The lead content of grass growing immediately near (≦ 1 m) roads was found to vary between 40 and 140 mg lead/kg dry matter. The lead content of samples taken from the same place at different times varies considerably, doubtless due to the influence of different exposure times, rate of growth and meteorological conditions. Different plants from comparable positions contain different amounts of lead; even different grass species vary. Roots, growing or otherwise, are protected from the action of dust and contain accordingly a low lead content which is independent of position. Drying fresh plant material in a forced draught oven, even at the low temperature of 35°C, causes losses of up to 50%. The risk to health of men and animals due to the consumption of plant foods growing near heavily used roads is discussed and preventative measures proposed.
Der Einfluß einer variierten K‐Ernährung auf die Inkorporierung von markiertem Stickstoff (15N) bei jungen Sonnenblumen (Helianthus annuus L.)
Authors: Mengel K. , Koch K.
Published: February 2007

The effect of a varied K nutrition upon the incorporation of labelled nitrogen (15N) in young sun flower plants (Helianthus annuus L.)

1. The influence of the potassium nutritional status upon the incorporation of labelled nitrogen (15N) into the soluble amino fraction and into the protein fraction was studied with young sun flower plants (Helianthus annuus L.). The plants were cultivated in a solution culture with 3 different nitrogen and 2 different potassium levels. During the last 24 hours of this cultivation the nitrogen of the nutrient solution was labelled by 15N‐nitrate in the various treatments.

2. The growth of the plants was affected considerably by the various nutritional treatments. The yield of the plant matter increased with increasing nitrogen supply. This nitrogen effect was enhanced by the better potassium nutrition.

3. The contents of soluble amino compounds in roots and upper plant parts increased with the increasing nitrogen application. This tendency was reduced by the higher potassium supply. The contents of protein nitrogen rose with the nitrogen nutrition. Potassium reduced the content of protein nitrogen in treatments with high growth rates.

4. Related on a single plant the incorporation rate of nitrate nitrogen into the organic matter was higher in plants with a good potassium nutritional status than in plants with a low potassium nutritional status. This effect was especially evident in the treatments with the highest nitrogen supply. Here the nitrate incorporation rate was 5–7 times higher with the higher potassium application.

5. This favorable effect of potassium upon the assimilation of nitrate nitrogen was also evident, if the incorporation rate was not related to a single plant, but on the unit of weight of plant material (fresh matter). Thus with high nitrogen supply the quantity of labelled nitrogen of the amino fraction was about 2 times higher in the plants with a high potassium nutritional status compared with plants of a low potassium nutritional status. In the protein fraction this potassium effect was still more evident. The influence of potassium upon the nitrate nitrogen assimilation was the better the better the plants were supplied with nitrate.
On the Adsorption of CaOH+ and BaOH+ by Clays and Soils
Authors: Papanicolaou E. P.
Published: February 2007

Über die Sorption von BaOH+ und CaOH+ durch Tone und Böden

Ein Ton (Wyoming Bentonit), ein Boden (Yolo Lehm von Davis, Kalifornien) und fünf verschiedene griechische Böden wurden mit Ba++ und Ca++ (Behandlung mit Ba(OH)2 und Ca(OH)2 unter CO2‐freier Luft) gesättigt. Die adsorbierte Barium‐ und Calciummenge wurde sowohl mittels isotopischer Verdünnung als auch aus Gesamtkationenmenge und Gesamthydroxidmenge bestimmt. Das adsorbierte Barium oder Calcium zeigte in beiden Fällen fast die gleichen Werte. Aus diesen Ergebnissen kann man schließen, daß eine Adsorption von CaOH+‐ und BaOH+‐Kationen sehr wahrscheinlich nicht stattgefunden hat.
Beziehungen zwischen Zink‐ und Kupfergehalt in Haferpflanzen und Böden
Authors: Beyme B.
Published: February 2007

Relationship between Zn and Cu Contents in Oat Plants and Soils

The Zn concentration in oatplants at the stage of appearing panicles from agricultural fields were higher and more varying on soils of sandy texture than on soils of loess. With the former Zn in plants correlated with n‐MgCl2 extractable Zn in the soil (r = 0.745), and also with 0,5 n‐HNO3 extractable Zn if the pH dependance was taken into account. Zn in plants from soils of loess correlated with HNO3 extractable Zn only. Cu concentrations in plants were lower on soils of sandy texture. A correlation to 0.5 n‐HNO3 extractable Cu in the soil existed in the group of loess derived soils only (r = 0.474), a negative correlation between Cu in plants and soil pH only with sandy soils (r = —0.500). Zn and Cu concentrations of plants were based on total N contents of plants instead of on dry matter, with the aim of mitigating growth dependent differences in Zn and Cu originating from unequal stage of plant development at harvesting.
Beziehungen zwischen Mangan‐Gehalten in Haferpflanzen und Böden
Authors: Beyme B.
Published: February 2007

Relationship between Mn in Oat Plants and Soils

The Mn concentration of oat plants in the stage of appearing panicles from agricultural fields were put in relationship to extractable Mn. With soils of sandy texture (clay < 4%, pH 4,7–6,6) a correlation existed between Mn in plants and n‐MgCl2 extractable Mn, however, no additional relationship with the easyly reducible Mn. A negative correlation between pH and Mn in plants was traced to the pH dependence of exchangeable Mn. With soils of loess (clay 5–28%, pH 6,6–7,7) a significant correlation existed between Mn in plants and easyly reducible Mn fractions (methods by Schachtschabel: extracting solutions containing Na2SO3, pH 8,0, or Na2SO3 + NaHSO3, pH 5,5), however, only if an interrelationship with the pH of the soil was allowed for. The higher the pH of the soil the lower its level of extractable Mn might be, to reach a certain concentration of Mn in plants. This relationship seems to be caused through a modifying influence of the soil pH on the reducing power of the extracting solutions.
Der Einbau radioaktiven Schwefels in Blattproteine von Ölrettichpflanzen
Authors: Pauler B.
Published: February 2007

The 35‐incorporation into protein components of oil radish plants

After a vegetation period of 4 weeks the fresh weight, dry weight and total protein content of the plants were not significantly affected by two different sulphur levels in the nutrient medium.

At defined conditions for protein extraction and fractionation, seven apparently identical protein fractions were observed in oil radish plants within the sulphur fertilization variants used.

The concentration and 35S‐labeling of some protein components were influenced by the amount of sulphur supplied.

Combining the results of Sephadex gel filtration and isoelectric focusing, it was possible to characterize the single protein components by their isoelectric points and molecular weight ranges.

Moreover, the rate of 35S‐labeling of total protein was increased by higher sulphur supply, while the 35S‐sulphate content in the protein extracts was deminished.
Schwefeldioxid, Schwefelwasserstoff, nitrose Gase und Ammoniak als ausschließliche S‐ bzw. N‐Quellen der höheren Pflanze
Authors: Faller N.
Published: February 2007

Sulphur dioxid, hydrogen sulphate, nitrous gases, and ammonia as sole source of S and N for higher plants

Long duration gasing experiments using SO2, H2S, nitrous gases and NH3, showed, that higher plants can use these gases as only source of S or N respectively, without affecting their normal growth during the whole vegetation period.

The sulphur and nitrogen of these high oxidized or high reduced gas forms were taken up by the plants and were also translocated to the roots.

The assimilation of sulphur, given as SO2, was more intensive than that given as H2S. The uptake of nitrogen, given as ammonia, was higher than that given as nitrous gases.
Aufnahme und Sorption von zwei‐ und dreiwertigem Eisen durch Sonnenblumenpflanzen (Heliantus annuus L.)
Authors: Höfner W.
Published: February 2007

Uptake and adsorption of ferrous and ferric iron by sunflower plants

The uptake of iron by 13 day‐old sunflower seedlings in water culture experiments was studied using FeCl3, Fe‐citrate and ferroammoniumsulfat (Mohr'sches Salz) in the‐nutrient solution.

By raising the N‐, K‐ and Ca‐content and lowering the P‐content of the nutrient solution at the same time the iron content of the exudate in the FeCl3‐treatment was increased up to 200 %. In the case of Fe‐citrate, similar values were obtained only under aeration conditions of the nutrient medium.

Application of iron as ferrous sulfate led to an increase of the iron content in the exudate and in the aerial plant parts amounting to about 200 and 400 %. respectively over that of the FeCl3 treatment.

After 15 hr‐uptake, most of the iron, taken up by the seedlings was in an unexchangeable form in the root system.

The results give a further evidence for the peferential uptake of iron in the ferrous form.
Translocation and respiration of assimilates in tomato plants as influenced by K nutrition
Authors: Haeder H. E. , Mengel K.
Published: February 2007

Assimilatverlagerung und Assimilatumsatz bei Tomatenpflanzen in Abhängigkeit von der Kaliumdüngung

14CO2‐Aufnahme sowie Transport und Verlust der markierten Assimilate durch Veratmung wurden an 3 Monate alten Tomatenpflanzen untersucht, die in unterschiedlichen K‐Konzentrationen in Wasserkultur angezogen worden waren.

Nach 6stündiger 14CO2‐Applikation war in den Blättern über die Hälfte des assimilierten 14C bereits in äthanolunlösliche Verbindungen eingebaut, was auf einen raschen Stoffumsatz schließen läßt.

Während der Nachtstunden wurde 1/3 der markierten Assimilate wieder veratmet, vor allem leichtlösliche organische Verbindungen. Bei geringer K‐Ernährung waren es auch schwerlösliche Substanzen.

Da die Pflanzen bei hoher K‐Versorgung größer waren als bei geringer, war die absolute 14CO2‐Assimilation der größeren Pflanzen doppelt so groß. Auch die spezifische Radioaktivität (n Ci/g FM) lag bei den Pflanzen mit hohen K‐Gaben um 20% hoher als bei den anderen Tomatenpflanzen. Dies läßt auf einen positiven Einfluß des Kaliums auf die CO2‐Assimilation schließen.

Den größten Einfluß übte die K‐Ernährung auf den Assimilattransport in die Speicherorgane aus; denn Pflanzen mit hoher K‐Versorgung hatten prozentual doppelt soviel markierte Verbindungen in Früchten und Wurzeln aufzuweisen, wie die gleichen Organe der Pflanzen mit geringerem K‐Ernährungszustand. Da diese Zahlen in Relativwerten zur Gesamtaktivität der Pflanze ausgedrückt wurden, zeigen sie, daß Kalium besonders den Assimilattransport fördert.
Untersuchungen über den Einfluß des Kinetins und des Eisens auf den Nukleinsäure‐ und Proteinstoffwechsel von Karottengewebekulturen
Authors: Neumann K.‐H.
Published: February 2007

The Influence of Kinetin and Iron on Nucleic Acid and Protein Metabolism of Carrot Tissue Cultures

Carrot‐root tissues cultured in a nutrient solution containing Kinetin had a high rate of cell division, that led to an undifferentiated callus, and a relatively low DNA content per cell. The same tissues growing without Kinetin had a smaller rate of cell division and a higher DNA content, and showed the ability to form roots.

By addition of 32P to the nutrient solution, the cultures growing with Kinetin showed a higher specific activity of DNA than those growing without Kinetin.

From previous experiments and results of other workers the possibility of the occurence of a metabolic labile DNA fraction in the cultures which grew without Kinetin is discussed.

A comparison between the influence of iron and Kinetin on cell division activity, root formation, DNA, RNA and amino acid content of the tissue cultures was made on a cell basis. Iron deficiency or absence of Kinetin in the nutrient solution reduced the cell division activity of carrot tissue cultures and increased the content of DNA, RNA and soluble amino acids. The protein content was reduced by iron deficiency but was increased by the absence of Kinetin.

Cultures, growing without Kinetin were able to form roots, while those, growing in an iron deficient medium were unable to show the latter phenomenon.
Abbau von Eisen(III)‐citrat in durchlüfteter wäßriger Lösung durch Bodenbakterien
Authors: Fischer W. R. , Ottow J. C. G.
Published: February 2007

Decomposition of iron(III)‐citrate in a well‐aerated, aqueous solution by soil bacteria

The decomposition of iron(III)‐citrate by soil bacteria in a well‐aerated NH4‐mineral salt solution at constant pH‐values between 3.3 and 8.5 resulted in a yellow (at low pH) or brown precipitate, respectively. The iron(III)‐precipitate is amorphous to X‐rays, contains approximately 12% carbon and about 40% iron (Fe). The freeze‐dried product is dissolved completely in an acid solution of ammonium oxalate.

Bacteria, capable of decomposing ammonium iron(III)‐citrate, were isolated by plate method and identified by morphological and physiological studies. They could be separated into two groups: The first group contained strains classified as Pseudomonas fluorescens, whereas members of the second group could be assigned to the new genus Acinetobacter.
Zur Abhängigkeit des Bodenwasserpotentials von der Temperatur
Authors: Richter J.
Published: February 2007

Soil‐water‐potentials depending on temperature

The soil‐water‐potential · of different soils has been measured in dependence of temperature. Between about — 0.2 · 106 and — 0.7 · 106 erg cm−3 (corresponding to a pressure head of 2 resp. 7 m water) all soils show a significant dependence of the soil‐water‐potential on temperature always in connection with hysteresis phenomena. With soils rich in clay or sand the dependence is most pronounced. At very high suction values (< — 0.7 · 106 erg cm−3) the dependence becomes small. Thus the measurements agree well with psychrometric evaluations of Campbell and Gardner (1971) on the no‐temperature‐dependence of the soil‐water‐potential in the range of about — 3 ·106 to — 20 ± 106 erg cm−3.
Kohlehydratfraktionen im reifenden Weizenkorn unter dem Einfluß von Stickstoff und Chlorcholinchlorid
Authors: Amberger A. , Kühbauch W.
Published: February 2007

Components of carbohydrates in wheat kernels during the ripening process influenced by nitrogen fertilization and chlorcholinchloride

The variability of carbohydrates was analysed in ripening kernels of wheat treated with nitrogen and chlorcholinchloride.

1. Proceeding ripening in wheat kernels (green, yellow, matured kernels) shows an important decrease of monosaccharides and total sugar. A distinct Influence of CCC — just as a possible postponement of ripening — marked with usually higher contents of monosaccharides and total sugar could be ascertained in green kernels only.

2. The synthesis of starch is not influenced by high nitrogen fertilization and essentially finished till the grain is yellow. By CCC‐treatment, compared with untreated plants, a much lower content of starch is caused in green and yellow grains, in matured such differences are detectable scarcely.

The decrease of starch content with high nitrogen fertilization is more important than that caused by CCC.
Zur pflanzenphysiologischen Bedeutung des Selens. II. Mitteilung: Untersuchungen zum Selenquotienten im Pflanzentest
Authors: Kramer W. , Ziechmann W.
Published: February 2007

Die nach einem 8wöchigen Oxydationsversuch in den Hydroponik‐ und Quarzsandgefäßen in unterschiedlichen Anteilen nachgewiesenen Mengen an Selenit und Selenat wurden hinsichtlich ihrer physiologischen Wirkung an jungen Weizenpflanzen untersucht. Hier ergab sich eine bemerkenswerte Abhängigkeit zwischen den Konzentrationsverhältnissen von Selenit und Selenat (Selenquotienten) und dem Pflanzenwachstum. Damit konnten Wirkungsgrad und Wirkungsbereich des Selenit‐ und des Selenat‐Ions als Funktion des Selenquotienten dargestellt werden. Aus der unterschiedlichen Schädigung von Sproß und Wurzel bei gleichzeitigem Angebot beider Ionen in einem Medium zeigt sich, daß die Wurzel vorwiegend durch Selenit und die Sproßteile durch Selenat geschädigt werden. Aus den Standardelektrodenpotentialen beider Ionen und ihren Schädigungsbereichen innerhalb der Pflanze läßt sich vermuten, daß in den Zellen von Wurzel und Sproß unterschiedliche potentiometrische Verhältnisse herrschen und darüber hinaus ein Redoxpotentialgefälle vom Sproß zur Wurzel vorliegt, welches für den Transport der Pflanzennährstoffe und den Abtransport der Assimilate von Bedeutung sein konnte.
Zur Methodik des Bodengashaushaltes I. Ökologisches Modell
Authors: Richter J.
Published: February 2007

The Evaluation of Soil Gas Ecology I: The Ecologic Model.
Ein vollautomatisches Pipettiergerät fär die Korngrößenbestimmung nach Köhn
Authors: Werner H.
Published: February 2007

A full automatic apparatus for grainsize analysis of soil according to Köhn.

For the purpose of rationalization of the mechanical analysis of soil according to Köhn a new pipette apparatus was constructed. The different fractions are taken by automatic pipettes, controlled by electric time switches. The construction and function is described.
Gesamtporenvolumen und Porengrößenverteilung in unbearbeiteten und bearbeiteten Lößböden
Authors: Ehlers W.
Published: February 2007

Total porosity and pore size distribution in untilled and tilled loess soils.

Soil core samples were taken from untilled and tilled soils of a no‐tillage experiment to determine total porosity and pore size distribution. The soil samples were collected at short time intervals during 1969–1971 from 2–6 cm depth of a Grey Brown Podzolic Soil (Typudalf) deriverd from loess.

1. Total porosity differed in untilled and tilled plots on the average by 4.7 vol.% (table 2). The seasonal changes are more pronounced on the tilled soil. Higher values of total porosity are observed during spring and fall, as compared to summer. Values are influenced by soil cultivation, rainfall and green manure crops (fig. 1a, b).

2. The changes of the fraction of large pores (> 30 μ), expressed on a volume basis, are similar to the changes in total porosity in direction but greater in extent. On the contrary the seasonal changes of the fractions of medium pores (3–30 μ), small pores (0,2–3,0 μ) and very small pores (< 0, 2 μ) appear to be independent from changes in total porosity (fig. la, b).

3. Fig. 2, showing the relation between total porosity and pore size distribution, may induce the wrong impression, that a decrease in total porosity results in an increase of the quantity of small and very small pores, accompanied with an excessive reduction of the quantity of large pores. If this relation is based on weight (100 g of solid soil particles) and not on volume (100 cm3 of soil particles and pores), it becomes clear, that compacting and loosening the soil investigated affect mainly the amount of large pores.

4. The seasonal changes of soil water content in the field influence pore size distribution. Under the condition of constant total porosity increasing water content at sampling date induces a pore size redistribution in favour of the pores > 300 μ and 1,5–3,0 μ (table 3).

5. A decrease in total porosity does not induce an increase in the homogeneity of the soil investigated (fig. 3).

6. The average total porosity of the untilled and tilled soil is near the lower and upper limit respectively of the range, which is considered to be the optimum for air capacity.
Eine Split‐root‐Technik zur Untersuchung der Nährstoffverfügbarkeit in Abhängigkeit vom Wassergehalt im Boden
Authors: Mengel K. , Braunschweig L. C. V. , Grimme H.
Published: February 2007

A Split‐Root Technique for the Investigation of the Relationship between Nutrient Availability and Soil Water content.

Nutrient availability in soils depends among other factors on soil water content. In order to investigate the quantitative relationship between availability and soil water content a special technique was developed. This split‐root technique has to fulfil several conditions.

1. This technique must be able to allow to differentiate between the direct influence of water supply on plant growth and the influence of soil water content on nutrient availability and the effect of the latter on plant growth.

2. It must grant a sufficient supply of water oxygen and all nutrients to the plant with the exception of that nutrient the availability of which is to be examined.

3. A predetermined water content or water tension should be maintained as constant as possible during the experiment.

These requirements are best met with by means a split‐root technique. The experiments were carried out in such a way that the plants were grown in a container consisting of three compartments of which the centre one contained quartz sand whereas the two outer compartments were filled with soil (fig.1). Each plant had half of its root system growing in the sand and half of it in the soil. The quartz sand was supplied with a nutrient solution containing all nutrients except the one the availability of which is to be examined. The water content of the soil was regulated by means of ceramic filter candles which were linked to a water reservoir. This water reservoir was kept under negative pressure according to the required water tension in the soil. The water tension in the soil was monitored by 2–4 tensiometers in each of the soil compartmens (tab.1).

Water tension up to pF 2.7 could be established and maintained in the soil. There was little variation of water tension during an experiment (3 weeks) and the moisture distribution in the soil was uniform. In order to obtain good reproducibilities the experiments were carried out in growth chamber.
The clay mineralogy of the Taworgha soils in Libya
Authors: Tahoun S. A. , Yousif A. F.
Published: February 2007

Die Tonminerale der Böden von Taworgha, Libyen

Der Tonmineralbestand der Taworgha‐Böden wurde mittels Röntgenanalyse und Elektronenmikroskopie bestimmt. Die Untersuchungen ergaben, daß die Böden tonmineralogisch qualitativ homogen und die vorherrschenden Minerale Hydroglimmer, Palygorskit, Montmorillonit und Chlorit sind. Quarz war in erwähnenswerten Mengen vorhanden, besonders in der Grobtonfraktion der Oberböden. Der Hydroglimmer ist trioktaedrisch. Es wild angenommen, daß etwas Vermiculit aus dem Hydroglimmer entstanden ist.
Die Podsolierungsstadien von Braunerden aus Schieferschutt
Authors: Zezschwitz E. V. , Schwertmann U. , Ulrich B.
Published: February 2007

Stages of Podsolization in Braunerden on Slate

A six member pedosequence between Braunerde and Braunerde‐Podzol on slate in the Rheinisch‐Westfälisches Bergland was described and analyzed. Macromorphology of the profiles comprises the transformation from mull‐like mor to raw humus and the appearance of a podzol A and B horizon. The results of a detailed iron fractionation using differential dissolution methods (total, dithionite, oxalate, pyrophosphate, KC1 soluble) clearly reflects change in Fe during podsolization. Silicate Fe (total minus, dithionite) decreases compensating part of Fe loss in the A horizon which accumulates in the B. The Fed maximum is in the strongest podsolized member (Braunerde‐Podsol), whereas the maxima of the more mobile Fe fractions (FeKCI, Fepy and partly Feo) as well as the oxalate soluble carbon occurs in the weaker podsolized members (podsolized Braunerde). Within the profiles the more mobile Fe fractions have their maximum in the horizon of strongest Fe mobilization (A) whereas the less mobile fractions show maxima in the horizon of immobilization (B).

The Fe fractionation improves proper horizontation of the profiles and proves the sequence to be a continuum. The change on ecological conditions is better indicated by decreasing amount of P than by changes in C and N although C/N is increasing along the series. Since the Braunerde is already very acid a change in exchangeable cations is not significant except an increase in exchangeable Fe and a decrease in exchangeable Mn. In the equilibrium soil solution an increase in H, Al and Fe and a decrease in Ca was noted. With increasing podsolization the turn over of Ca between soil and plant appears to decrease. The local distribution of the soils with varying degree of podsolization in this mountainous forest region appears to depend on such factors as inclination, exposition and forest history.