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91.
The Static Fertilization Experiment Bad Lauchstädt (1902) consists of a crop rotation of sugar beets, spring barley, potatoes and winter wheat. Three farmyard manure (FYM) treatments and six mineral fertilizer treatments are combined orthogonally. Comparing the first and last decades, crop yields nearly doubled. In unfertilized plots, yields and N uptake by crops also increased when comparing first and last decades. On average for the decade 2001–2010, N uptake in unfertilized plots amounted 51.6 kg ha?1. Although soil organic carbon (SOC) levels for unfertilized plots remain almost unchanged, SOC increases slowly in the most highly fertilized treatment, resulting in a gradual widening of differences in SOC between the most extreme treatments to 0.952%. Climate change and increased harvesting and root residues due to rising yields are suggested as an explanation. Except for the plot with the highest application of mineral and organic fertilizer, in all treatments more N was taken up by crops than was applied by fertilizers. Higher FYM input leads to more unfavourable N balances because N release from FYM cannot be controlled. Considering atmospheric N input, only in the exclusively mineral fertilized treatment is N balanced out. Similar results are found for C balances: the exclusively mineral fertilized treatment shows the most favourable C balance. 相似文献
92.
Anna-Sophie Hager Michael Czerny Jürgen Bez Emanuele Zannini Elke K. Arendt 《Journal of Cereal Science》2013
Specific dietary requirements, e.g. celiac disease, as well as increased consumer demand for products of high nutritional value, makes the production of pasta from alternative cereals interesting. Raw material characterisation showed that the utilisation of oat and teff flour is beneficial as these ingredients contain higher levels of fibre and mineral composition is superior to that of wheat. Starch properties significantly influence pasta quality and therefore damaged starch levels, amylase activity, pasting properties and gelatinisation temperatures of the flours were investigated. Fresh egg pasta based on wheat, oat and teff flour was produced. Sensory properties of oat spaghetti were found to be very close to that of wheat pasta but improvement of smoothness and aroma is necessary, while teff spaghetti showed reduced sensory quality. An in vitro enzymatic digestion was performed using a dialysis system to mimic the behaviour of pasta as eaten and make predictions on the glycemic index (GI). The predicted GI was highest for wheat pasta, followed by teff and oat. Ultra structure was studied using confocal laser scanning microscopy, allowing the visualisation of differences in starch granule size and shape as well as gelatinisation occurring during the cooking process. 相似文献
93.
Outi E. Mäkinen Emanuele Zannini Elke K. Arendt 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(1):90-95
Germination can be used to improve the sensory and nutritional properties of cereal and pseudocereal grains. Oat and quinoa are rich in minerals, vitamins and fibre while quinoa also contains high amounts of protein of a high nutritional value. In this study, oat and quinoa malts were produced and incorporated in a rice and potato based gluten free formulation. Germination of oat led to a drastic increase of α-amylase activity from 0.3 to 48 U/g, and minor increases in proteolytic and lipolytic activities. Little change was observed in quinoa except a decrease in proteolytic activity from 9.6 to 6.9 U/g. Oat malt addition decreased batter viscosities at both proofing temperature and during heating. These changes led to a decrease in bread density from 0.59 to 0.5 g/ml and the formation of a more open crumb, but overdosing of oat malt deteriorated the product as a result of excessive amylolysis during baking. Quinoa malt had no significant effect on the baking properties due to low α-amylase activity. Despite showing a very different impact on the bread quality, both malts influenced the electrophoretic patterns of rice flour protein similarly. This suggests that malt induced proteolysis does not influence the technological properties of a complex gluten free formulation. 相似文献
94.
95.
96.
Mathias Craul Lounes Chikhi Vitor Sousa Andriatahiana Rabesandratana Elke Zimmermann 《Biological conservation》2009,142(12):2862-2871
Madagascar’s diverse and mostly endemic fauna and flora suffer from recent landscape changes that are primarily caused by high levels of human activities. The loss and fragmentation of forest habitats are well known consequences of human activities. In this study, we investigate the effects of forest fragmentation on presence, abundance and genetic diversity in a larger-bodied lemur species, Lepilemur edwardsi, in northwestern Madagascar. In addition, we characterized the genetic differentiation among populations and demographic changes. We found L. edwardsi at only 13 (76.5%) of 17 visited sites, 11 of which were situated in the Ankarafantsika National Park (ANP). We captured between two and 17 individuals per site. We sequenced the mtDNA d-loop of all samples and genotyped 14 microsatellite loci in two exemplary populations for demographic analyses. A negative influence on forest fragmentation could be detected, since the fragments had a lower genetic diversity than sites in the ANP. Genetic differentiation between populations ranged from low to high but was almost always significant. A typical pattern of isolation-by-distance could not be detected and the data could rather be interpreted as results of random genetic drift. The data furthermore revealed signals of a demographic collapse of about two orders of magnitude in the two exemplary sites. This decline probably started during the last few hundred years of intensified human disturbances and population growth. Given the results of this study, urgent conservation actions are needed and should concentrate on an effective protection of the few remaining populations in order to ensure the long-term survival of L. edwardsi. 相似文献
97.
Identification of areas with similar restrictions to crop productivity could improve the efficiency to manage agricultural systems, guarantee stable yields, and reduce the effect of droughts in rainfed systems. The ability of any vegetation index to discriminate N and moisture-related changes in leaf reflectance would present an important advantage over the present diagnostic system which involves soil-testing for moisture and available N. The purpose of the study was to calibrate different vegetation indices regarding their capacity to identify water and nitrogen availability for rainfed corn crops in the semiarid Pampas of Argentina. A field experiment with corn with a control without fertilization (N0), and fertilized with 120 kg ha?1 of nitrogen (N120) was used. Two sites, Low (L) and High (H), were identified within the field, according to their altimetry, a multi-spectral aerial photography was taken from a manned airplane during flowering stage of the corn crop, and four spectral indices were calculated (NDVI, green NDVI, NGRDI, (NIR/GREEN)-1). At six georeferenced points at each site soil texture, organic matter, available phosphorus, nitrogen and moisture contents as well as corn aerial biomass and grain yield were determined. The two sites differed in most of the evaluated soil properties, crop biomass and grain yield. The spectral information obtained at crop flowering showed clear differences between sites H and L for all four indices, indicating that any of these would be able to detect the differences in soil moisture and fertility among these environments. Both (NIR/GREEN)-1 and green NDVI had the best correlation with crop yield determined in the field, and therefore could be considered most appropriate for estimating corn yields from images taken at flowering. For estimation of N requirements, green NDVI differentiated best between fertilized and non-fertilized crop in the moisture limited environment (H), while (NIR/GREEN)-1 performed better in the site where soil moisture was non-limiting (L). 相似文献
98.
Elke Noellemeyer Federico Frank Cristian Alvarez German Morazzo Alberto Quiroga 《Soil & Tillage Research》2008,99(2):179-190
Land-use change affects vast areas of the semiarid region of central Argentina, where agriculture becomes predominant over mixed farming systems, and large areas of permanent pastures (PAS) are being converted to agricultural land. This land-use change causes loss of soil structure, but very little is known about the effect of changes in aggregate size distribution on soil physical, chemical and biological properties. We decided to use dry sieved aggregates since this technique is commonly used in semiarid regions. The study was carried out at Anguil, La Pampa, Argentina. The soil was a sandy loam Entic Haplustoll with a carbonate-free A-horizon. The PAS site had been under weeping love grass for more than 40 years. Parts of this PAS were turned to cultivation in 1989 (CULT14) and in 2001 (CULT2). Sampling was carried out at 0.6 m intervals to 0.18 m depth. Bulk density (BD), organic carbon (OC), and water holding capacity and infiltration were determined on these samples. Dry aggregate size distribution and OC content of the size fractions were determined on large undisturbed samples. Samples of pooled aggregate size fractions >4, 1–4, and <1 mm, as well as corresponding samples of non fractionated soil were incubated and respiration was measured by CO2 evolved. The soil of CULT2 had 29% lower contents of large (>4 mm) and 37% higher contents of very small (<1 mm) aggregates than PAS. The intermediate size aggregates were not affected by the short-term effect of tillage. OC loss in CULT2 was 16% regarding PAS. Longer term effects of cultivation were characterized by 30% loss of intermediate size aggregates, 22% increase of bulk density, 74 and 19% decrease in water infiltration and water retention, respectively of CULT14 compared to PAS. A 32% decrease of OC was observed after 14 years of cultivation. Intermediate size aggregates had highest OC contents and no difference between treatments was found, except for a lower value of large aggregates in CULT14. Respiration rates and total CO2 evolved was related to OC contents of fractions; however, PAS respired more from its small aggregates than expected from their OC content. The results showed that OC turnover and loss of aggregation was very fast in this soil, but soil hydraulic properties were affected in the longer term. Dry aggregates were found to useful for studying soil degradation, and they showed similar trends as those indicated in the literature for water stable aggregates. 相似文献
99.
Von Elke Scheurmann 《Reproduction in domestic animals》1974,9(2):58-68
Inhalt Bei 10 mutterlos aufgezogenen neugeborenen Kälbern des Schwarzbunten Niederungsrindes wurden Ruheverhalten and Aktivität 4 Tage lang mittels fotogra-fischer Dauerüberwachung registriert. 5 weitere Kälber wurden auf der Weide mit ihren Müttern zusammen beobachtet, um die bei den mutterlosen Kälbern gefundenen Daten vergleichend interpretieren zu können. Die mutterlosen Kälber waren in den ersten 4–8 Stunden p. p. besonders aktiv. Ihre Aktivität nahm bis zum Ende des ersten Lebenstages ab. Nach dem Saugen suchten die Kälber auf der Weide besondere Liegeplätze auf: Man kann annehmen, daß die Kälber des europäischen Rindes zu den Abliegejungen zu zählen sind. Contents (Studies on activity and rest behaviour in newborn calves) Resting behaviour and activity in 10 newborn German Blackpied calves, reared with-out their dams, were recorded by photography for 4 days p. p. 5 more calves were kept on pasture with their dams for observation to find a comparative interpretation of the calves behaviour. All motherless calves exhibited high activity during the first 4–8 hours p. p. Activity declined till the end of the first day. On pasture calves spent their resting periods on separate lying places to where they returned after sucking. It is concluded, that the calves of European cattle have to be classified as remote-kept young. 相似文献
100.
Kaden V Renner C Rothe A Lange E Hänel A Gossger K 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):362-367
The oral immunisation of wild boar against classical swine fever (CSF) in Baden-Württemberg is described and evaluated. The bait vaccine based on the CSF virus (CSFV) strain "C" proved to be safe in wild boar of all age classes. The modified immunisation procedure consisting of three double vaccinations per year was very effective. CSFV was not detected beyond the second immunisation campaign. The average rate of seropositive wild boar diagnosed over all immunisation periods was 49.2%. The seroprevalence rate increased significantly during the first year of immunisation and reached its maximum after the third vaccination period with 72% antibody positive animals. The higher percentage of seropositive young boars in this field trial compared to the seroprevalence rates in this age class in other field trials in Germany may be attributed to the new vaccination scheme. Factors that may be responsible for the decreased herd immunity after the fourth or sixth immunisation period are discussed. 相似文献