摘要:

Effect of Mineral Fertilizer Application on the Diffusion of Cations that have not been Added with the Fertilizer.Mineral fertilizer application increases the concentration of all cations in the soil solution, because the cations added displace partly those cations occupying exchange positions into the soil solution. In pot experiments, therefore, the K concentration could be raised by Mg‐fertilization and vice versa.In the first experiment the response of alfalfa to Mg fertilization was to be studied. 1.2 g Mg/pot (12 kg soil/pot) was applied before sowing and 0.5 g/pot after each cut. 1.0 g P/pot as CaHPO4was added, but no K was added in the first year (except soil No. 6 K). In the 2ndyear 1 g K/pot was added after each cut. At 3 sampling dates soil samples were taken for diffusion measurements.In a second experiment K availability was tested at different K and soil water contents. 4 K treatments were included (0, 9, 29 and 49 mg K/100 g). K and Mg diffusion were measured.In the first experiment an increase of K concentration in the soil solution was recorded (Tab. 1) and in the second one an increase of Mg concentration (Fig. 1). This increase of concentration took place without altering the amounts present in the soil, but it led to an increase of the diffusive flux of the cations in question (Tab. 1 Fig. 2).This is taken as further evidence that cation diffusion takes place in the soil solution and depends mainly on the cation concentration in the soil solution.In those cases in which the cation availability depends mainly on cation diffusion to the roots mineral fertilizer application may affect the supply of cations that have not been added to the soil.This effect will be important in pot experiments to which large amounts of fertilizer are applied and which are not subject to leaching. It cannot be detected by most of the conventional soil testing methods because the amounts of cations ‐ except, of course, those that have been added ‐ have not changed. Only an analysis of the soil solution will reveal whether this „salt effect”︁ is significant or not in a sp

ISSN:0044-3263    

DOI:10.1002/jpln.19751380302

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

The decomposition of straw‐cellulose‐lignin by Pleurotus florida and its use..1Holocellulose, alpha‐cellulose and lignin in wheat straw are regularly decomposed by Pleurotus Florida. The absolute quantities of individual components are not altered in relation to dry mass. The commencing mass (wheat straw) is reduced by decomposition to 20%.2The difference between the spent compost and a substratum stored for an identical period under semianaerobic conditions will be the greater, depending upon how much more favourable the conditions (for example oxigen) were for fruitingbody development.3The water and glucose solubility of the substratum (time function of Pleurotus growth) is shown at various temperatures and with the use of various extraction media. It can be seen that the water solubility of the substratum increases with the duration of Pleurotus growth.4About 10% of wheat straw substratum is converted into fruiting‐body (Pleurotus Florida), 70% is given off as CO2and H2O as loss. The remaining 20% of the original mass is spent compost.5With harvesting of the fruiting‐bodies part of the nutrient is removed. The final constitution of the spent compost is altered by the selective removal of nutrients by the Pleurotus mycelium and harvesting of the fruiting‐bodies. In this process, Ca and Mg show a relative increase, whereas N, K and P decrease slightly.6The change of Pleurotus substratum was with spectroscopic analysis by 280 nm determined.7Spent compost can be used as plant manure or ba

ISSN:0044-3263    

DOI:10.1002/jpln.19751380303

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Die Bindung von Immissionsblei in Böden.Durch Bleisättigung isolierter Sorptionsträger bei unterschiedlichen pH‐Werten und durch Extraktionsanalysen an bleikontaminierten Böden wurden folgende Ergebnisse erzielt:.DerHumusträgt am meisten zur Immobilisierung von Blei in Böden bei. Der Einfluß der Humusform auf die Sorptionskapazität für Blei kann zu einem großen Teil auf den Polymerisationsgrad zurückgeführt werden. Die koordinative Bindung des Bleis an Gruppen mit freien Elektronenpaaren wird als entscheidender Reaktionsmechanismus der humusspezifischen Bleisorption erachtet. Daneben konnte auch Bleisalzbildung an polaren Gruppen festgestellt werden. Entsprechend diesen Bindungsformen nehmen die Bleisorptionskapazität und die Stabilität der Humus‐Blei‐Komplexe mit sinkendem pH‐Wert ab.Der niedrige. aber eindeutig erfaßbare Anteil derTonmineralean der Bleibindung in Böden beruht auf zwei pH‐abhängigen Sorptionsmechanismen. Bei pH7 und darüber bestimmenchemischeEigenschaften der Reaktionspartner die Bleisorption. In Analogie zur Säure‐Base‐Reaktion wird Blei von SiOH, AlOH und AlOH2‐Gruppen der Mineraloberflächen nicht elektrolyt‐austauschbar gebunden. Bei pH ≦ 7 bestimmen vorwiegendphysikochemischeEigenschaften der Reaktionspartner das Ergebnis einer physisorptiven Bleiadsorption.Unterhalb des isoelektrischen Bereiches wird Blei von amorphem Fe‐Oxidhydrat, Goethit undHämatitaufgrund seiner Hydroxyl‐affinität adsorbiert. Die nicht elektrolytaustauschbare Bleibindung an den Oxidoberflächen scheint quantitativ weit stärker vom Verhältnis Oberfläche: Volumen der Oxide abzuhängen als von der Oxidform selbst.Aufgrund dieser Ergebnisse wird gefolgert, daß eine Bleikontamination des Grundwassers durch vertikalen Transport bei Böden durchschnittlichen Entwicklungsgrades nicht anzunehmen ist. Dies wird auch durch die Abhängigkeit der Bleigehalte von der Zeitdauer der Bleiimmission in straßennahen Oberflächenhorizonten bestätigt.Dagegen kann die Bleiakkumulation in Oberflächenhorizonten zu einer vermehrten Einbeziehung von Blei in ökologische Kreisläufe führen, mit zunehmender Gefahr für die Nahru

ISSN:0044-3263    

DOI:10.1002/jpln.19751380304

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Effect of NaCl and Na2SO4on dry matter production, mineral content and organic compounds of spinach and lettuce.In water culture experiments the effect of 2,5 meq and 25 meq NaCl and Na2SO4respectively on dry matter production and content of mineral elements, chloroplasts pigments and carbohydrates in lettuce (salt sensitive) and spinach (salt tolerant) has been studied.With increasing Na‐supply the dry matter production was decreased in lettuce and increased in spinach. With increasing Na‐supply in both species the content of K, Mg and Ca in the leaves decreased. This decrease was more pronounced with sulfate as accompanying anion (Na2SO4) and induced already deficiency in Ca and Mg. This induced deficiency of Mg was reflected especially in lettuce in lower contents of chloroplasts pigments.In both plant species there was no effect of the Na salt treatments on the content of phosphorus or nitrogen in roots or leaves.The carbohydrate content in both species was strongly affected by the Na salt treatments. Irrespectively of the accompanying anion this effect occured already at the low Na supply and before the dry matter production was influenced. In leaves and roots of lettuce the contents of glucose, fructose and sucrose was considerably decreased; this decrease was less expressed in the starch content. In spinach the Na supply only decreased the carbohydrate content in the roots whereas in the leaves especially the sucrose content was increased. This different effect of Na on carbohydrate content in spinach and lettuce could be an indication of different action of Na on carbohydrate metabolism, namely inhibited synthesis in lettuce and inhibited translocation in spinach.The results demonstrate that in studies on the effect of increasing Na salt concentrations besides the osmotic effects also the ion specific effects have to be carfully considered. These ion specific effects are competition of Na+with other cations during uptake and the influence of Na on the cell metabolism, especially on the pathway of carbohydrates.The authors thanks Mrs.Hwie Juen Tjandraatmadjafor her engaged help in various laboratory wo

ISSN:0044-3263    

DOI:10.1002/jpln.19751380305

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Chromium and mercury in a soil after 80 years of treatment with urban sewage water.A soil (tab. 1) which is since 80 years under irrigation with sewage water contains 112 ppm Cr and 1.5 ppm Hg (Fig. 1). The sewage water presently contains 0.07 ppm chromium and 0.002 ppm mercury. In order to study the migration and leaching of chromium in the soil experiments were carried out with51Cr as CrO42‐under aerobic and51Cr als Cr3+under anaerobic conditions in undisturbed soil columns. In all cases chromium was adsorbed in the layer 0–5 cm (Fig. 2 and 3). Similar experiments with203Hg as HgCl2(Fig. 4) showed that mercury ist adsorbed near the surface. These experiments confirmed our results of ground water analyses, neither chromium nor mercury contaminated the ground wa

ISSN:0044-3263    

DOI:10.1002/jpln.19751380306

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Effect of calcium supply on growth rate and calcium content of potato tubers..Using potato plants in water culture with a constant calcium supply to the roots, a study was made of the influence of additional supply of calcium to the tuber surface on growth rate and calcium content of the tubers.Under conditions of high relative humidity around the tubers the calcium nutrition of the tubers was exclusively dependent on the calcium supplied to the tuber surface („exogenous calcium”︁). With a high level of exogenous Ca the growth rate of the tubers was high and the rate of uptake of Ca was proportional to the tuber growth. With a low level of exogenous Ca the growth rate declined to a lower but constant value. In absence of exogenous supply of Ca the growth rate of the tubers declined gradually until growth ceased. Cessation of tuber growth occurred when the Ca content decreased below 0,36 mg Ca per g dry matter for smaller tubers and below 0,14 mg Ca per g dry matter for larger tubers.Severe Ca deficiency in potato tubers causes necrosis at the tuber

ISSN:0044-3263    

DOI:10.1002/jpln.19751380307

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Uptake and Translocation of Diethyl Phosphoric acid Ester in Comparison to the Orthophosphate..The uptake of the diethyl phosphoric acid ester (DEP) through intact adventive roots of maize plants and its further translocation to the shoots was studied over a wide range of concentrations (0.001–50.0 mM P/L) in comparison to the orthophosphate (MP). The effect of the relative humidity (r.h.) and the metabolic inhibitor Na N3on both processes, uptake and translocation, was also investigated.At low concentrations the plants tended to retain a greater part of the MP intaked in the absorbing roots. Depression of the transpiration streaming influenced relatively the phosphate translocation to the shoots. The higher the MP‐outside‐concentration was, the greater the effect of the transpiration streaming was on its translocation. Treatment with 10‐4MNaN3inhibited MP‐accumulation but not its translocation from the treated roots.The results showed that passive processes are mainly responsible for the DEP‐uptake and translocation by the maize plants. Both processes were dependent to a great extent on the transpiration streaming.The r.h. affected the translocation patterns of both DEP and MP dissimilarly at low concentration, though, they come close to each other when their outside concentrations were increased.The results are discussed on the basis of the symplasm theory (2) and the dual mechanisms of ion

ISSN:0044-3263    

DOI:10.1002/jpln.19751380308

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Effect of applications of phenyl‐ureas, ‐carbamates and ‐amides on synthesis of sugar in carrots.In field and pot trials with mineral and peaty soil respectively lower moor the synthesis of sugar was studied with carrots treated with herbicides of the type of phenyl‐ureas, ‐carbamates and amides. In field trials the success of the chemical weed control determines the yield and sugar content. In pot trials the application of herbicides diminishes the yield and formation of sugar. From the 3 predominant sugars of carrots (glucose, fructose and sucrose) the disaccharid is reduced the most in spite of frequently unchanged respectively slowly increased reducing sugars. It is supposed, that the synthesis of disaccharides from monosaccharides is inhibited by an increased activity of ph

ISSN:0044-3263    

DOI:10.1002/jpln.19751380309

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

The effectiveness of nitrogen in slow‐release synthetic‐organic nitrogen fertilizer materials and mixed fertilizers containing a slow‐release nitrogen component.In an incubation trial conducted for a period of 16 weeks at 30°C and 100% R.H. the release of nitrogen was studied from 20 slow‐release nitrogen fertilizers and mixed fertilizers containing a slow‐release nitrogen component on an urea‐aldehyde basis. Amounts equivalent to 500 mg N per kg dry soil were added to a diluvial sandy soil having a pH‐KCl of 5.44 and a moisture content of 55% of the maximum retentive capacity. On the average, 35% of the slow‐release nitrogen was released, 60% of which during the first 4 weeks. The best measure of the amount of N released was the amount of cold‐water soluble N in the fertilizers. The amount of N released exceeded the amount of applied cold‐water soluble N on the average by about 4%, which was also the percentage of released cold‐water insoluble nitrogen.The differences among the individual fertilizers were rather large. In a supplementary trial it was found that the various urea‐aldehyde combinations do not react alike to pH and moisture content of the soil, and that they for that reason can hardly be lumped together with respect to their nitrogen effect. Each of these materials is more or less a special‐purpose fertilizer, and as such less suited as a substitute for the conventional fast‐actin

ISSN:0044-3263    

DOI:10.1002/jpln.19751380310

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY

摘要:

Reduction of stalk length in winter and summer rye by Ethrel (2‐chloroethylphosphonic acid).In pot experiments with winter and summer rye Ethrel (2‐chloroethylphosphonic acid) considerably reduced stalk length so that a favourable effect on lodging can be expected. The shortening effect strongly depends on the time of application. Grain yield is scarcely affected. The experiments give indication for the optimal concentration and the amount of active substance requi

ISSN:0044-3263    

DOI:10.1002/jpln.19751380311

出版商:WILEY‐VCH Verlag    

年代:1975

数据来源: WILEY