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221.
Pekka Vähäoja Petteri Piltonen Anna Hyvönen Jouko Niinimäki Jorma Jalonen Toivo Kuokkanen 《Water, air, and soil pollution》2005,165(1-4):313-324
This study focuses on the biodegradability measurements of tall oil-based wood preservatives and their raw materials in groundwater as determined by the respirometric BOD OxiTop method. Certain substances were also analyzed in standard conditions described by OECD 301 F. Results show that creosote oil, a traditional wood preservative, does not biodegrade at all in groundwater over a period of 28 days, while tall oil and linseed oil biodegrade to some degree (13.4% and 14.8%, respectively). On the other hand, degrees of biodegradation of linseed oil, tall oil and creosote oil in the extra mineral and microbe including conditions described by OECD 301 F were 72.9%, 54.3% and 24.9% after 28 days, respectively. Studied raw materials of tall oil-based wood preservative production biodegrade to some degree in groundwater (variability from 11.9% to 18%) and quite effectively in OECD 301 F test (variability from 39% to 71.7%) over a period of 28 days. Abiotic degradation may also be significant with the studied substances. 相似文献
222.
Stanislav Torma Jozef Vilček Stanislav Kužel Anna Martensson 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(4):358-366
With increasing demand for sustainable production, the need to effectively utilise site-based resources increases. One such resource is the remaining crop residues, both above and below ground, after harvest. In order to assess the magnitude of this resource, this study determined the plant nutrient contribution of residues from 17 different crops in seven different regions of Slovakia over a nine-year period. The soil profile 0.0–0.3?m was taken into account at belowground residues sampling. The results showed that winter rape, mustard, corn maize, triticale, winter rye with straw and sunflower left the most residues, exceeding 8 tons of dry biomass per hectare. Root crops (sugar beet, potatoes) and peas left less than 3 tons of residual dry biomass per hectare. Using these data, the nutrient potential coefficient, i.e. the amount of nutrients left by production of one ton of the main product was calculated by polynomial regression. With these coefficients and the known yield of a given crop, it was possible to calculate how much nitrogen, phosphorus and potassium each crop leaves in the soil after harvest. It was found that the amount of nitrogen left ranged from 20 to 132?kg, phosphorus from 2 to 24?kg and potassium from 13 to 218?kg per hectare. This has to be taken into account when calculating the fertiliser requirement of the subsequent crop in order to achieve better resource utilisation, thereby reducing the risk of eutrophication and improving farm profits by reducing expenditure on fertiliser. 相似文献
223.
Leguminous leys are important sources of nitrogen (N), especially in forage-based animal production and organic cropping.
Models for estimating total N2 fixation of leys—including below-ground plant-derived N (BGN)—are based on grazed or harvested leys. However, green manure
leys can have different proportions of above-ground plant-derived N (AGN) and BGN when subjected to different cutting regimes.
To investigate the effects of cutting on N distribution in white clover, a pot experiment was carried out using 15N techniques to determine N2 fixation, N rhizodeposition and root C and N content of cut and uncut white clover (Trifolium repens L. cv. Ramona) plants. Percentage N derived from air (%Ndfa) was lower in uncut (63%) than in cut (72%) plants, but total
Ndfa was not significantly affected by cutting. The higher reliance on N2 fixation in cut plants was thus counterbalanced by lower biomass and total N content. With BGN taken into account, total
plant-derived N increased by approximately 50% compared with AGN only. Cutting did not affect the proportion of BGN to standing
shoot biomass N after regrowth, but decreased the proportion of BGN to total shoot biomass production during the entire growth
period. Thus, estimates of N fixation in green manure leys should consider management practices such as cutting regime, as
this can result in differences in above- and below-ground proportions of plant-derived N. 相似文献
224.
Jónsdóttir R Sveinsdóttir K Magnússon H Arason S Lauritzsen K Thorarinsdottir KA 《Journal of agricultural and food chemistry》2011,59(8):3893-3904
Flavor characterization and quality of salt-cured and desalted cod (Gadus morhua) products was studied using sensory analysis and gas chromatography techniques. The products were produced in Iceland using two different processing methods (filleting and splitting) and three different salting procedures, i.e., the old single-step kench salting or a multistep procedure, and presalting (injection and brine salting or only brine salting), which was followed by kench salting. The main difference observed was between fillets and split fish, where the split fish was darker and had stronger flavor characteristics. Comparison of different salting procedures showed that the use of presalting improved the appearance of the salted products, which can be described as increased lightness and reduced yellowness of the products. In the same products, the intensity of curing flavors was milder, as described by sensory analysis and key aroma compounds. Derivatives from lipid and protein degradation contribute to the characteristic flavor of the salted products. 相似文献
225.
Siwei Shi Qingzhong Zhang Yilai Lou Zhangliu Du Qian Wang Ning Hu Yidong Wang Anna Gunina Jiqing Song 《Soil Use and Management》2021,37(1):95-103
Biochar addition can expand soil organic carbon (SOC) stock and has potential ability in mitigating climate change. Also, some incubation experiments have shown that biochar can increase soil inorganic carbon (SIC) contents. However, there is no direct evidence for this from the field experiment. In order to make up the sparseness of available data resulting from the long‐term effect of biochar amendment on soil carbon fractions, here we detected the contents and stocks of the bulk SIC and SOC fractions based on a 10‐year field experiment of consecutive biochar application in Shandong Province, China. There are three biochar treatments as no‐biochar (control), and biochar application at 4.5 Mg ha?1 year?1 (B4.5) and 9.0 Mg ha?1 year?1 (B9.0), respectively. The results showed that biochar application significantly enhanced SIC content (3.2%–24.3%), >53 μm particulate organic carbon content (POC, 38.2%–166.2%) and total soil organic carbon content (15.8%–82.2%), compared with the no‐biochar control. However, <53 μm silt–clay‐associated organic carbon (SCOC) content was significantly decreased (14%–27%) under the B9.0 treatment. Our study provides the direct field evidence that SIC contributed to carbon sequestration after the biochar application, and indicates that the applied biochar was allocated mainly in POC fraction. Further, the decreased SCOC and increased microbial biomass carbon contents observed in field suggest that the biochar application might exert a positive priming effect on native soil organic carbon. 相似文献
226.
Tatjana Gavrilenko Olga Antonova Anna Ovchinnikova Lubov Novikova Ekaterina Krylova Nina Mironenko Galina Pendinen Anna Islamshina Natalia Shvachko Stephan Kiru Ludmila Kostina Olga Afanasenko David Spooner 《Genetic Resources and Crop Evolution》2010,57(8):1151-1164
The germplasm collections of the Vavilov Institute of Plant Industry, Russia represent the first germplasm collection made for potatoes, now numbering 8,680 accessions. It has tremendous historical and practical importance and a rich history, having been used to document a polyploid series in the cultivated species, to formulate initial taxonomic hypotheses in potato, for studies of interspecific hybridization, and serving as the germplasm base for Russian breeding efforts. Despite its importance and size, there has never been a study of its molecular diversity, and there were many gaps in its passport data. The purpose of the present study is to obtain morphological, ploidy, and microsatellite (SSR) data needed to set up a useful subset of the collection of cultivated potatoes and closely related wild species, and to use this collection to study cultivated potato taxonomy and phylogeny. Through assessments of viability, passport data, and chromosome counts, we selected a subset of 238 cultivated and 54 wild accessions. A morphological and nuclear SSR study of these collections distinguished only three cultivated species: Solanum curtilobum, S. juzepczukii and S. tuberosum, not the many more cultivated potato species of prior taxonomic treatments. The SSR study supports the ideas of S. acaule as one of the parental species for S. curtilobum and S. juzepczukii. The morphological and SSR results are very similar to other recent studies of cultivated species, and show the need to reclassify the collection of cultivated potatoes by modern taxonomic criteria. 相似文献
227.
Arnoldi A Dallavalle S Merlini L Musso L Farina G Moretti M Jayasinghe L 《Journal of agricultural and food chemistry》2007,55(20):8187-8192
A series of N-mono- or N, N-disubstituted [2-(2,4-dichlorophenyl-3-(1,2,4-triazol-1-yl)]propylamines and N-[2-(2,4-dichlorophenyl-3-(1,2,4-triazol-1-yl)propyl]amides were synthesized and tested for their fungicidal activity in vitro and in vivo against a group of plant pathogenic fungi. Some compounds exhibited a fairly good in vitro activity. The replacement of the ether group of tetraconazole with a secondary or tertiary amino group leads to compounds that maintain the antifungal activity on several phytopathogenic fungi, provided that the substituents are not too bulky or lipophilic. The allyl, propargyl, and cyclopropyl groups appear particularly suitable. Although these compounds have some structural similarities with terbinafine and naftifine, which act as squalene epoxidase inhibitors, they maintain the usual mechanism of action of the other triazoles. 相似文献
228.
Dinnella C Minichino P D'Andrea AM Monteleone E 《Journal of agricultural and food chemistry》2007,55(21):8423-8429
The impact of an in vitro procedure that mimics the physiochemical changes occurring in gastric and small intestinal digestion on the bioaccessibility and antioxidant activity of phenols from 10 extra-virgin olive oil samples was assessed. Extra-virgin olive oil phenols were totally extracted in the aqueous phase, which reproduces gastric fluids during the digestion procedure. A linear bioaccessibility model, based on tyrosol behavior in model oil samples, was used to estimate the bioaccessibility index (BI%) of extra-virgin olive oil phenols. The BI% varied amongst samples from a maximum of 90% to a minimum of 37%, thus indicating that only a fraction of phenols can be considered bioaccessible. The specific antioxidant activity of olive oil phenols proved to be negatively affected by the digestion procedure. By computing a principal component analysis, it was possible to show that differences in the potential bioactive effect of extra-virgin olive oil samples were related to different phenolic profiles. 相似文献
229.
Characterization of commercial kava-kava herbal drug and herbal drug preparations by means of nuclear magnetic resonance spectroscopy 总被引:1,自引:0,他引:1
Bilia AR Bergonzi MC Lazari D Vincieri FF 《Journal of agricultural and food chemistry》2002,50(18):5016-5025
The efficiency of one- and two-dimensional NMR experiments in characterizing the content of the constituents of both herbal drugs and herbal drug preparations is demonstrated for kava-kava. These experiments directly detect active constituents represented by kavalactones in both a finely powdered herbal drug and a commercial extract. In addition, NMR spectroscopy can detect all other compounds present in the extract. As previously evidenced, NMR experiments can represent a generally applicable technique for rapid screening and are a complement to the classical analytical techniques such as high-performance thin-layer chromatography, high-performance liquid chromatography, capillary gas chromatography, and electrophoresis. These experiments can be considered a very simple and fast analytical method to obtain a fingerprint of the herbal drugs and their preparations, and to quantify the content of the active principles of the extract. 相似文献
230.
In order to observe the spatial phosphorus (P) fractions transformations in sediments in relation to bacterial abundance and enzyme hydrolysing organic P-alkaline phosphatase (APA), samples from 35 stations from eutrophic Sulejow Reservoir were taken in spring after flood and in summer after cyanobacterial bloom breakdown. The results show pronounced fluctuations: decrease of average total P in sediments, despite organic matter delivery after cyanobacterial bloom, in parallel with increase of labile P (8.3%) and Ca-bounded P (16.6%) fractions and decline of organic P fraction (28.5%). Higher alkaline activity in sediments in the spring delivered nutrients to water column and supported cyanobacterial bloom development during the summer. Positive correlation between APA and organic P (r?=?0.37, p?<?0.01, n?=?70) and negative with labile inorganic P (r?=??0.44, p?<?0.01, n?=?70) in sediments proved significant role of the APA in phosphorus transformation in sediments and internal loading in the reservoir. During summer, APA was significantly related to bacterial number (r?=?0.36, p?<?0.01, n?=?35) and bacterial abundance was correlated to organic matter content (r?=?0.36, p?<?0.01, n?=?35). Such pattern of temporal variations of P transformation in sediments indicates order of solutions for enhancement of recultivation effects of eutrophic dam reservoirs: (1) reduction of organic matter supply in spring and (2) sediment inactivation during summer. 相似文献