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1.
Atmospherical sulfur deposition in Schleswig-Holstein In order to quantify the atmospherical sulfur deposition and to investigate factors for the depositions variability during 1983 precipitation samples from five meteorological stations in Schleswig-Holstein were collected. Using the bulk-sample method dry and wet deposition were recorded together. In the year of the investigation sulfur-deposition was 20 kg/ha S in List on Sylt, 19 in Schleswig, 11 in Kiel, 14 in Lübeck and 17 in Quickborn near Hamburg. There was no correlation between sulfur concentration and pH value of the samples. In contrast sulfur-concentration showed a close relation to amount of weekly precipitations. On many soils sulfur is only added by atmospherical deposition, which is sometimes not sufficient to meet the requirements of agricultural crops in Schleswig-Holstein. Having a negative sulfur balance in soils an increase of sulfur deficiency is expected in the future. 相似文献
2.
Recently S deficiency became one of the most widespread nutrient disorders in North-European agriculture. Therefore precise and reliable methods for the evaluation of the S nutritional status of agricultural crops are required. For the prognosis of the plant available S soil analysis would be a favourite method, however, no relation between plant S concentrations and mobile (extractable sulphate plus extractable organic S) S contents in soils could be stated. The reasons for the impracticability of traditional soil tests seem to be related to interactions between soil water and mobile S in soils, so that site specific models need to be developed for the prognosis of the S status of agricultural crops. 相似文献
3.
Genotypical Differences in the Nutrient Uptake of Winter Wheat
In order to investigate genotypical differences in the nutrient uptake of winter wheat cultivars the nutrient content of young wheat plants grown during 1982–1984 on three Brown Earth sites of Schleswig-Holstein were analysed.
Significant differences between the cultivars could be found in the content of the plants at shooting stage in P, K, Ca, Fe, Mn and Zn. The maximal difference between highest and lowest content (mean of 3 years) was about 20 % for P, K, Ca, Mn and Zn and 40 % for Mn. Since at shooting stage the dry matter production of the cultivars was about the same, the measured differences in nutrient concentrations may also represent differences in nutrient uptake.
Due to the low Mn-supply of the test soils the cultivars with the lowest Mn-uptake also produced the lowest grain yield.
By use of discriminant analysis it could be shown that the cultivars displayed a typical pattern of the nutrient concentrations. In the whole population two general types in nutrient pattern were found which are different in their concentrations of P, K, Ca and Zn. 相似文献
In order to investigate genotypical differences in the nutrient uptake of winter wheat cultivars the nutrient content of young wheat plants grown during 1982–1984 on three Brown Earth sites of Schleswig-Holstein were analysed.
Significant differences between the cultivars could be found in the content of the plants at shooting stage in P, K, Ca, Fe, Mn and Zn. The maximal difference between highest and lowest content (mean of 3 years) was about 20 % for P, K, Ca, Mn and Zn and 40 % for Mn. Since at shooting stage the dry matter production of the cultivars was about the same, the measured differences in nutrient concentrations may also represent differences in nutrient uptake.
Due to the low Mn-supply of the test soils the cultivars with the lowest Mn-uptake also produced the lowest grain yield.
By use of discriminant analysis it could be shown that the cultivars displayed a typical pattern of the nutrient concentrations. In the whole population two general types in nutrient pattern were found which are different in their concentrations of P, K, Ca and Zn. 相似文献
4.
E Bloem S Haneklaus J Kesselmeier E Schnug 《Journal of agricultural and food chemistry》2012,60(31):7588-7596
The emission of gaseous sulfur (S) compounds by plants is related to several factors, such as the plant S status or fungal infection. Hydrogen sulfide (H(2)S) is either released or taken up by the plant depending on the ambient air concentration and the plant demand for S. On the contrary, carbonyl sulfide (COS) is normally taken up by plants. In a greenhouse experiment, the dependence of H(2)S and COS exchange with ambient air on the S status of oilseed rape ( Brassica napus L.) and on fungal infection with Sclerotinia sclerotiorum was investigated. Thiol contents were determined to understand their influence on the exchange of gaseous S compounds. The experiment revealed that H(2)S emissions were closely related to pathogen infections as well as to S nutrition. S fertilization caused a change from H(2)S consumption by S-deficient oilseed rape plants to a H(2)S release of 41 pg g(-1) (dw) min(-1) after the addition of 250 mg of S per pot. Fungal infection caused an even stronger increase of H(2)S emissions with a maximum of 1842 pg g(-1) (dw) min(-1) 2 days after infection. Healthy oilseed rape plants acted as a sink for COS. Fungal infection caused a shift from COS uptake to COS releases. The release of S-containing gases thus seems to be part of the response to fungal infection. The roles the S-containing gases may play in this response are discussed. 相似文献
5.
The most important active compound in garlic is alliin. Sulfur (S) fertilization was shown to significantly increase the alliin concentration in garlic cloves, while high nitrogen (N) levels had an adverse effect. The effect of graded N and S application on the storage life of garlic has been paid little attention so far. A bifactorial field trial with 4 levels of N and S was conducted in a randomized block design. At harvest, 40 bulbs per treatment were stored under terms comparable to the storage conditions in average households (20 °C, dry, and dim) for 83 days. Every 3 weeks, samples were analyzed for their alliin and water content. The alliin concentration in peeled garlic cloves increased during storage from on average 9.2 mg g(-1) dry weight at harvest to 21.4 mg g(-1) dry weight after 83 days of storage. S fertilization increased the alliin concentration by a factor of 2.3 from 11.4 mg g(-1) in the control treatment to 26.6 mg g(-1) dry weight at the highest S level of 45 kg ha(-1) after 83 days of storage. N fertilization decreased by a trend of the alliin content. Fertilizer rates had only a minor influence on water losses from bulbs at short-term storage. After 83 days of storage, water losses were by trend lower at higher S levels, and this relationship proved to be significant when no N was applied. Best quality in terms of high alliin contents was obtained during the entire storage time at an S level of at minimum 30 kg ha(-1) S if no N was applied. The results show that the physiological S demand of 15 kg ha(-1) S for optimum yield is lower than the S requirement of 30 kg ha(-1) S for a longer storage life. 相似文献
6.
Bettina Eichler-Löbermann Sigrid Köhne Britta Kowalski Ewald Schnug 《Journal of plant nutrition》2013,36(4):659-676
ABSTRACT Phosphorus (P) is a limited resource and its efficient use is a main task in sustainable agriculture. In a 3-year field experiment the effects of catch cropping [oil radish (Raphanus sativus), buckwheat (Fagopyrum esculentum), serradella (Ornithopus sativus), ryegrass (Lolium westerwoldicum), and phacelia (Phacelia tanacetifolia)] of organic fertilization (cattle manure and biowaste compost) and of inorganic fertilization (Triple-Superphosphate) on plant and soil parameters were investigated on a P-poor loamy sand in Northeast Germany. The catch crops were sown in September and remained on the plots until next spring. Then the main crops oilseed rape (Brassica napus), spring barley (Hordeum vulgare), or spring wheat (Triticum aestivum) were cultivated. The yield and P uptake of the main crops were determined. Furthermore, in the soil the organic matter content, pH, phosphorus (P) in soil solution (Psol), double-lactate and oxalate P content, P sorption capacity, and degree of P saturation were measured. All applied forms of fertilizer affected the P contents in soil and the yields and P uptakes of main crops. For green fertilization especially phacelia was found to contribute to the P supply of the main crops, since it increased the P uptake as well as the P contents in soil significantly. The cultivation of ryegrass led to a reduction of the P availability in soil. For example, in average of the three years the Psol content was 0.35 mg L? 1when phacelia was cultivated and 0.22 mg L? 1 when ryegrass was cultivated. The cultivation of phacelia had a comparable effect on soil and plant parameters as the organic and mineral fertilization. An improved P availability and P utilization by catch cropping can reduce the need for external P input which may help to save the limited P resources worldwide. 相似文献
7.
1. Flock balances of nitrogen, phosphorus, zinc and copper (N, P, Zn, Cu) were calculated in order to evaluate environmental effects of three different broiler production systems (intensive indoor, free range and organic). 2. Nutrient gain in birds per unit nutrient intake (retention) in intensive indoor production was higher than in free range and organic production. 3. Nutrient surplus relative to nutrient retention was higher in organic production than in free range and intensive indoor production. 4. The main reasons for differences in nutrient efficiency between intensive indoor, free range and organic production were duration of growth period, strain of broilers and feeding strategy. 5. The calculation of whole farm indicators (livestock density, N and P excretions per hectare of farmland) demonstrates how defining system boundaries affects the outcome of an evaluation: organic farms had the smallest livestock densities and the lowest N and P excretions per hectare of farmland. 6. In the efforts to reach a more holistic evaluation of agricultural production systems, the definition of adequate system boundaries must be discussed. In addition to nutrient balances, further indicators of sustainability, such as human and ecological toxicity, should be considered. 相似文献
8.
Shiping Wang Yanfen Wang Silvia Haneklaus Xuerong Xing Zhengyi Hu Xiaohui Fan Zuozhong Chen Ewald Schnug 《植物养料与土壤学杂志》2005,168(2):228-232
Grassland‐livestock farming is the main agricultural activity in the Inner Mongolia steppe of China. It has been estimated that more than 80% of the grasslands suffer from sulfur (S) deficiency in this region. In an incubation study and a greenhouse experiment with alfalfa, the influence of soil moisture (40% and 70% water‐holding capacity, WHC), nitrogen (0 and 200 mg N (kg soil)–1 as NH4NO3), and elemental sulfur (eS; 0 and 300 mg S (kg soil)–1) amendments on the apparent eS oxidation, eS‐oxidation rate, net S‐mineralization rate, and S uptake of alfalfa were studied. After 28 d of incubation, the eS‐oxidation rate was four times higher at 70% than at 40% WHC if no N was applied. With N application, soil moisture had only minor effects on eS oxidation during the whole incubation period. In the greenhouse experiment, lower values for eS‐oxidation rate and net S‐mineralization rate were found if no N was applied. Application of N and eS significantly increased alfalfa growth and S uptake. The results of both experiments suggest that combined N and eS applications are the best way to alleviate S deficiency on these calcareous soils. 相似文献
9.
H B?hnel P Lohavanijaya S Rungin C Schnug H S Seifert 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(8):289-295
Mechanisms of host defence in Crustaceae and vibriosis in shrimp and methods for its prevention are discussed as introduction. The own work deals with the development of a site-specific multivalent anti-vibrio vaccine and its application in Thailand. The vaccine was produced in a continuous bioreactor system from field strains of Vibrio alginolyticus, V. harveyi, V. parahaemolyticus and V. vulnificus, purified through ultrafiltration, and inactivated by formalin. It was applied to Penaeus monodon PL prior to release into the ponds via artemia larvae. As mean result from numerous trials carried out under commercial field conditions in Eastern Thailand it was shown that the PL tolerated the vaccine perfectly. Due to technical problems only few of the field trials could be monitored until harvest. The data available allow claiming an obvious protective effect of the vaccine. 相似文献
10.
E.-A. Kaiser K. Kohrs M. Kücke E. Schnug J. C. Munch O. Heinemeyer 《Biology and Fertility of Soils》1998,28(1):36-43
N2O emission rates from a sandy loam soil were measured in a field experiment with 2 years of perennial forage crops (ryegrass,
ryegrass-red clover, red clover) and 1 year of spring barley cultivation. Spring barley was sown after the incorporation of
the forage crop residues. All spring barley plots received 40 kg N ha–1 N fertiliser. Ryegrass, ryegrass-red clover and red clover plots were fertilised with 350 kg N ha–1, 175 kg N ha–1 and 0 kg N ha–1, respectively. From June 1994 to February 1997, N2O fluxes were continuously estimated using very large, closed soil cover boxes (5.76 m2). In order to compare the growing crops, the 33 months of investigation were separated into three vegetation periods (March–September)
and three winter periods (October–February). All agronomic treatments (fertilisation, harvest and tillage) were carried out
during the vegetation period. Large temporal changes were found in the N2O emission rates. The data were approximately log-normally distributed. Forty-seven percent of the annual N2O losses were observed to occur during winter, and mainly resulted from N2O production during daily thawing and freezing cycles. No relationship was found between the N2O emissions during the winter and the vegetation period. During the vegetation period, N2O losses and yields were significantly different between the three forage crops. The unfertilised clover plot produced the
highest yields and the lowest N2O losses on this soil compared to the highly fertilised ryegrass plot. Total N2O losses from soil under spring barley were higher than those from soil under the forage crops; this was mainly a consequence
of N2O emissions after the incorporation of the forage crop residues.
Received: 31 October 1997 相似文献