Plant availability and leaching of 15N-labelled mineral fertilizer residues retained in agricultural soil for 25 years: A lysimeter study     

Peter Sørensen  Betina N. Pedersen  Ingrid K. Thomsen  Jørgen Eriksen  Bent T. Christensen 《植物养料与土壤学杂志》2023,186(4):441-450

Background

A high use-efficiency of fertilizer N remains essential to sustain high crop productivity with low environmental impact. However, little is known on the long-term lability of mineral fertilizer N.

Aims

To quantify crop uptake and leaching of ¹⁵N-labelled mineral fertilizer that has been retained in an agricultural soil for 25–30 years in crops with variable growing season.

Methods

A field plot received ¹⁵N-labelled mineral fertilizers over a period of 5 years and was then kept under arable cropping for 12 years. After relocation to 16 lysimeters, the topsoil grew set-aside grassland for the next 13 years. Then crop uptakes and leaching losses of ¹⁵N remaining in soil was tested over a 2-year period by either converting set-aside grass to production grassland, or by replacing it with spring barley (+/− autumn cover crop) or vegetation-free fallow. All treatments received unlabelled mineral N fertilizers.

Results

Crop uptake and leaching of ¹⁵N were generally highest in the first test year after termination of the set-aside. The leaching of residual ¹⁵N in soil declined in the order: vegetation-free soil (4.7%), spring barley (1.9%), spring barley + cover crop (0.7%) and production grassland (0.2%). Corresponding losses for the second leaching period were 2.7%, 0.9%, 0.4% and 0.06%. There was a fixed relationship between leaching losses of ¹⁵N and total N.

Conclusions

After residing in soil for 25–30 years, the lability of labelled mineral N fertilizer residues appeared slightly higher than the lability of bulk soil N. Autumn vegetation was crucial for reducing leaching losses.  相似文献   

A novel IS element, ISMpa1, in Mycobacterium avium subsp. paratuberculosis     

Olsen I  Johansen TB  Billman-Jacobe H  Nilsen SF  Djønne B 《Veterinary microbiology》2004,98(3-4):297-306

A novel insertion element belonging to the IS110 family was identified in Mycobacterium avium subsp. paratuberculosis. The IS element, ISMpa1, is 1500 bp and has one ORF encoding a putative transposase. Three copies of ISMpa1 were identified in the M. avium subsp. paratuberculosis genome. The element had inserted into the 3' end of the highly conserved mycobacterial genes prrB and a homologue of M. tuberculosis Rv1593c, and between a putative cytochrome p450 oxygenase and a putative hydrolase. The IS element was present in all (n = 11) M. avium subsp. paratuberculosis strains but not detected in most other mycobacterial species examined, including 10 M. avium subsp. avium isolates of human, avian and porcine origin. However two porcine isolates of M. avium subsp. avium and the reference strain IWGMT49 did harbour ISMpa1. These three strains belong to a previously described subgroup of M. avium subsp. avium based on IS1245 restriction fragment length polymorphism (RFLP) pattern and serovars. All of the M. avium subsp. paratuberculosis strains examined had an identical RFLP pattern when probed with sequences corresponding to the 5' end of ISMpa1, whereas a different pattern was seen in the positive M. avium subsp. avium strains. This novel IS element might be a useful tool in strain classification of M. avium subsp. avium and also for the identification of M. avium subsp. paratuberculosis when used in combination with IS900.  相似文献   

Detection of Mycobacterium avium subsp. paratuberculosis by buoyant density centrifugation, sequence capture PCR and dot blot hybridisation     

Halldórsdóttir S  Englund S  Nilsen SF  Olsaker I 《Veterinary microbiology》2002,87(4):327-340

Detection of Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) by polymerase chain reaction (PCR) is often hampered by the lack of efficient methods for sample treatment. We report a protocol for analysis of faecal samples based on buoyant density centrifugation in Percoll and IS900 sequence capture PCR combined with a dot blot assay for detection of low-grade infection of M. paratuberculosis. Serial dilutions of M. paratuberculosis genomic DNA and M. paratuberculosis bacteria were used to assess the sensitivity of the method. The final evaluation was performed with spiked faecal samples, which also were analysed by culture. The presence of PCR inhibitory substances in processed faecal samples was evaluated by including a PCR internal control. By using buoyant density centrifugation, sequence capture PCR, and dot blot hybridisation, we achieved a sensitivity of 10(3)CFU (colony forming units)/g of faeces. The detection limit by culture was assessed to 10(2)CFU/g of faeces. We conclude that the described protocol is a fast and sensitive alternative to bacterial culture of faecal samples.  相似文献   

RADIOGRAPHIC FEATURES OF PRIMARY AND CONCOMITANT FLEXOR ENTHESOPATHY IN THE CANINE ELBOW     

Evelien de Bakker  Jimmy H. Saunders  Henri van Bree  Ingrid Gielen  Bernadette Van Ryssen 《Veterinary radiology & ultrasound》2013,54(2):107-113

Primary flexor enthesopathy is a recently recognized elbow disorder and should be considered in the differential diagnosis of elbow lameness. For treatment planning purposes, it is important to make a distinction between primary and concomitant forms of the disease. The purpose of this prospective study was to compare radiographic findings for dogs with primary flexor enthesopathy (n = 17), concomitant flexor enthesopathy (n = 24), elbow dysplasia (n = 13), and normal dogs (n = 7). All dogs underwent a complete radiographic examination and each radiographic image was evaluated for the presence or absence of following characteristics: irregular medial humeral epicondyle, spur and calcified body. Additionally, the presence or absence of other elbow disorders (medial coronoid process disease, osteochondritis dissecans, ununited anconeal process, incongruity, subtrochlear sclerosis, and osteoarthritis) was recorded. Radiographic characteristics of flexor enthesopathy were found in 86% of painful joints in the primary flexor enthesopathy group and in 100% of painful joints in the concomitant flexor enthesopathy group. Radiographic characteristics of flexor enthesopathy were not found in sound elbow and elbow dysplasia groups. Frequencies and details of individual radiographic characteristics did not differ between primary and concomitant flexor enthesopathy groups. Findings support the use of radiography as a first screening method for detection of flexor enthesopathy, but not as a technique for distinguishing primary vs. concomitant forms.  相似文献   

The prevalence and clinical relevance of hyperkalaemia in calves with neonatal diarrhoea     

Florian M. Trefz  Annette Lorch  Melanie Feist  Carola Sauter-Louis  Ingrid Lorenz 《Veterinary journal (London, England : 1997)》2013,195(3):350-356

One hundred and twenty-four calves with neonatal diarrhoea were investigated in order to assess the prevalence of hyperkalaemia and the associated clinical signs. Hyperkalaemia (potassium concentration >5.8 mmol/L) was recognized in 42 (34%) calves and was more closely associated with dehydration than with decreases in base excess or venous blood pH. In 75 calves with normal blood concentrations of D-lactate (i.e. ?3.96 mmol/L), K concentrations were moderately correlated with base excess values (r = ?0.48, P < 0.001). In contrast, no significant correlation was observed in 49 calves with elevated D-lactate. Only three hyperkalaemic calves had bradycardia and a weak positive correlation was found between heart rate and K concentrations (r = 0.22, P = 0.014). Ten of the 124 calves had cardiac arrhythmia and of these seven had hyperkalaemia indicating that cardiac arrhythmia had a low sensitivity (17%) but a high specificity (96%) as a predictor of hyperkalaemia.In a subset of 34 calves with base excess values ??5 mmol/L and D-lactate concentrations <5 mmol/L (of which 22 had hyperkalaemia), changes in posture/ability to stand could be mainly explained by elevations of K concentrations (P < 0.001) and to a lesser extent by increases in L-lactate concentrations (P = 0.024). Skeletal muscle weakness due to hyperkalaemia alongside hypovolaemia may produce a clinical picture that is similar to that in calves with marked D-lactic acidosis. However, since reductions in the strength of the palpebral reflex are closely correlated with D-lactate concentrations, a prompt palpebral reflex can assist the clinical prediction of hyperkalaemia in calves presenting with a distinct impairment in their ability to stand (specificity 99%, sensitivity 29%).  相似文献   

Antibodies to OspC,OspF and C6 antigens as indicators for infection with Borrelia burgdorferi in horses     

B. Wagner  L. B. Goodman  A. Rollins  H. S. Freer 《Equine veterinary journal》2013,45(5):533-537

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A Male Genetic Map Designed for Quantitative Trait Loci Mapping in Norwegian Cattle     

Dag Inge Våge  Ingrid Olsaker  Helge Klungland  Luis Gomez-Raya  Sigbjørn Lien 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):56-63

A male bovine linkage map was constructed using six half-sib families of the Norwegian Cattle population. The family material consisted of six sires and 285 sons, with the number of sons per sire ranging from 32 to 71. Of the 288 markers analysed, 261 were anonymous microsatellites and 27 were coding genes. Eleven of the coding genes were mapped by a two-step procedure involving intron/exon sequencing in the six sires and development of polymerase chain reaction-based methods for efficient genotyping in heterozygous families. Linkage analysis including both informative and non-informative sons was performed in order to obtain unbiased estimates of recombination fractions. The autosomal genome length of the Norwegian Cattle Map (NCM) was estimated as 2682 cM, with an average interval of 12.5 cM. The map provides sufficient marker density for scanning the whole bovine genome to locate quantitative trait loci. The large number of common markers between NCM and previously published maps will contribute to the comparison and integration of bovine maps.  相似文献   

Food-based dietary guidelines and implementation: lessons from four countries--Chile, Germany, New Zealand and South Africa     

Keller I  Lang T 《Public health nutrition》2008,11(8):867-874

OBJECTIVE: Food-based dietary guidelines (FBDGs) are globally promoted as an important part of national food and nutrition policies. They are presented within policy as key features of the strategy to educate the public and guide policy-makers and other stakeholders about a healthy diet. This paper examines the implementation of FBDGs in four countries: Chile, Germany, New Zealand and South Africa - diverse countries chosen to explore the realities of the FBDG within policy on public health nutrition. DESIGN: A literature review was carried out, followed by interviews with representatives from the governmental, academic and private sector in all four countries. RESULTS: In all four countries the FBDG is mainly implemented via written/electronic information provided to the public through the health and/or education sector. Data about the impact of FBDGs on policy and consumers' food choice or dietary habits are incomplete; nutrition surveys do not enable assessment of how effective FBDGs are as a factor in dietary or behavioural change. Despite limitations, FBDGs are seen as being valuable by key stakeholders. CONCLUSION: FBDGs are being implemented and there is experience which should be built upon. The policy focus needs to move beyond merely disseminating FBDGs. They should be part of a wider public health nutrition strategy involving multiple sectors and policy levels. Improvements in the implementation of FBDGs are crucial given the present epidemic of chronic, non-communicable diseases.  相似文献   

Stabilization mechanisms of organic matter in four temperate soils: Development and application of a conceptual model   总被引：2，自引：0，他引：2  

Margit von Lützow  Ingrid Kögel‐Knabner  Bernard Ludwig  Egbert Matzner  Heinz Flessa  Klemens Ekschmitt  Georg Guggenberger  Bernd Marschner  Karsten Kalbitz 《植物养料与土壤学杂志》2008,171(1):111-124

Based on recent findings in the literature, we developed a process‐oriented conceptual model that integrates all three process groups of organic matter (OM) stabilization in soils namely (1) selective preservation of recalcitrant compounds, (2) spatial inaccessibility to decomposer organisms, and (3) interactions of OM with minerals and metal ions. The model concept relates the diverse stabilization mechanisms to active, intermediate, and passive pools. The formation of the passive pool is regarded as hierarchical structured co‐action of various processes that are active under specific pedogenetic conditions. To evaluate the model, we used data of pool sizes and turnover times of soil OM fractions from horizons of two acid forest and two agricultural soils. Selective preservation of recalcitrant compounds is relevant in the active pool and particularly in soil horizons with high C contents. Biogenic aggregation preserves OM in the intermediate pool and is limited to topsoil horizons. Spatial inaccessibility due to the occlusion of OM in clay microstructures and due to the formation of hydrophobic surfaces stabilizes OM in the passive pool. If present, charcoal contributes to the passive pool mainly in topsoil horizons. The importance of organo‐mineral interactions for OM stabilization in the passive pool is well‐known and increases with soil depth. Hydrophobicity is particularly relevant in acid soils and in soils with considerable inputs of charcoal. We conclude that the stabilization potentials of soils are site‐ and horizon‐specific. Furthermore, management affects key stabilization mechanisms. Tillage increases the importance of organo‐mineral interactions for OM stabilization, and in Ap horizons with high microbial activity and C turnover, organo‐mineral interactions can contribute to OM stabilization in the intermediate pool. The application of our model showed that we need a better understanding of processes causing spatial inaccessibility of OM to decomposers in the passive pool.  相似文献   

An integrative approach of organic matter stabilization in temperate soils: Linking chemistry,physics, and biology   总被引：1，自引：0，他引：1  

Ingrid Kögel‐Knabner  Klemens Ekschmitt  Heinz Flessa  Georg Guggenberger  Egbert Matzner  Bernd Marschner  Margit von Lützow 《植物养料与土壤学杂志》2008,171(1):5-13

With this topical issue, we present the work of the Priority Program 1090 of the German Research Foundation (“Deutsche Forschungsgemeinschaft DFG”): “Soils as a source and sink for CO₂ – mechanisms and regulation of organic matter stabilisation in soils”. This introduction gives an overview on the sites investigated and the major research approaches, including a glossary of major terms used in the field of soil organic matter research. We point out the advantages of integration of data from a broad field of different soil‐science disciplines and the progress achieved by application and combination of new analytical methods describing the quality and turnover of soil organic matter.  相似文献