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排序方式: 共有216条查询结果,搜索用时 0 毫秒
191.
Niemczyk Marzena Chmura Daniel J. Socha Jarosław Wojda Tomasz Mroczek Piotr Gil Wojciech Thomas Barb R. 《European Journal of Forest Research》2021,140(6):1341-1361
European Journal of Forest Research - The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this... 相似文献
192.
Henrik Bak Topbjerg Kacper Piotr Kaminski Kirsten Kørup Kåre Lehmann Nielsen Hanne Grethe Kirk Mathias Neumann Andersen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(5):400-411
A drought screening experiment focusing on intrinsic water use efficiency (WUEi) was carried out among 132 clones belonging to a dihaploid potato mapping population. The clones were exposed to progressive soil drying during a five-day period in a greenhouse pot experiment. Analysis of the underlying variables was done based on a multivariate data analysis strategy. The strategy successfully divided the clones into WUEi performance categories. Differences between clonal WUEi responses were traced back to differences in the net photosynthetic rate. Stomatal conductance (gs) did not vary significantly between the clones. Leaf abscisic acid (ABA) concentration and leaf water potential were found to reflect known isohydric behaviour for potato, and a non-linear relationship could be established for gs and leaf ABA concentration across the WUEi groups. Similarly, a common non-linear relationship between leaf ABA concentration and soil water potential was found. The latter findings suggest that the investigated population did not harbour significant genetic variation as to ABA production as function of soil desiccation level or with respect to the sensitivity of stomatal aperture vis-à-vis leaf ABA concentration and soil water potential. 相似文献
193.
The measurement of wood surface roughness is performed once the machining process is completed. It requires considerable time since the measurement is performed at slow speed. The objective of this study was to develop a method to evaluate the surface roughness of paper birch wood while routing. For this purpose, a number of transducers were mounted on the router spindle and also in the proximity of the workpiece and cutting zone. Signals were acquired during a wide range of cutting conditions and analyzed. Statistical regression and artificial neural networks were employed to establish relationships between the signals and the actual cutting depth and surface roughness. The sensor selection and the feasibility of the sensor placement were determined. The models were subjected to a validation procedure to confirm their performance. The placement of the microphone at constant distance from the cutting zone was determined to be the most useful one. A model able to predict the surface roughness of routed paper birch wood regardless of the depth of cut was produced. The performance of the model was valid independently of the length of the workpiece. 相似文献
194.
Joanna O'Keeffe Mikoaj Piniewski Mateusz Szczeniak Pawe Oglcki Piotr Parasiewicz Tomasz Okruszko 《Fisheries Management and Ecology》2019,26(6):474-485
Climate change is expected to affect the flow regime, cause loss of habitat, change community composition and behavioural habits of fish. This study assessed the impact of climate change on ecologically relevant streamflow conditions for fish migration and spawning in the Vistula and the Odra river basins. Streamflow simulations obtained with the Soil and Water Assessment Tool (SWAT) for the historical period and two future horizons were driven by nine bias‐corrected EURO‐CORDEX Regional Climate Models under two greenhouse gas concentration trajectories. This study identified a subset of Indicators of Hydrological Alteration (IHA) that are relevant for pike, Esox lucius L., chub, Squalius cephalus (L.), and Atlantic salmon, Salmo salar L. IHA indicators were calculated and compared for different scenarios. An index‐based framework identified that all considered species will be impacted by climate change, with Atlantic salmon facing the largest impact. The model's uncertainty was addressed through an aggregation method that assessed inconsistencies in the model's response. 相似文献
195.
196.
Transgenic cucumber lines expressing the chimeric pGT::Dhn24 gene do not show enhanced chilling tolerance in phytotron conditions 下载免费PDF全文
197.
Stanisław Świtek Viktoria Takacs Zuzanna Sawinska Tomasz Kosiada Piotr Tryjanowski 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(4):311-316
The negative impact on the environment caused by intensive agriculture has been extensively discussed for years. In particular, excessive nitrogen application has been associated with biodiversity loss. Many studies have shown the potential to reduce the use of nitrogen without any impact on crop yield. Maintaining crop yield has been the goal, whereas crop quality has not been considered. In this paper, we investigate the effect of the level of soil organic carbon (SOC) and nitrogen fertiliser application on winter wheat (Triticum aestivum) yield and its quality. We show that the absence of nitrogen fertiliser decreased both yield and quality parameters of cereal grain. Quality parameters, such as protein and gluten contents, zeleny value, falling number and hardness were strongly positively influenced by nitrogen fertiliser application. The SOC level had no significant effect on these grain quality parameters. As a result, in the absence of nitrogen fertiliser, grain was not suitable for baking bread. We recommend that in the debate on the potential to limit the use of nitrogen in agricultural production, its impact on grain quality should be taken into consideration, especially at low levels of SOC. 相似文献
198.
Edyta Łokas Przemyslaw Wachniew Dariusz Ciszewski Piotr Owczarek Nguyen Dinh Chau 《Water, air, and soil pollution》2010,207(1-4):57-71
This study focuses on the distribution of selected trace metals, 137Cs and 210Pb, in floodplain deposits of the lowland Warta River (southern Poland) downstream of Cz?stochowa, a large city with an iron smelter. The depth profiles of trace metal (Zn, Pb, Cu, Ni, Cd and Mn), 210Pb and 137Cs contents in floodplain sediments were used to derive deposition rates on the floodplain for the twentieth century. The applicability of particular chronometric tools is considered within the context of their mutual relationships and confirmed by the consistency of the results. Deposition rate estimates for the past 50 years based on the vertical patterns of trace metal concentrations, which were correlated with particular events in the development of the smelter, range from 0.4 cm·year?1 in profiles situated in backswamps far from the channel to over 1.1 cm·year?1 in profiles of the natural levee adjacent to the river. Deposition rates based on 210Pb inventories in the profiles range from 0.08 to 0.66 g·cm?2·year?1, which corresponds to linear sedimentation rates of 0.10 to 0.91 cm·year?1, respectively. Dating of characteristic levels associated with peak fallout of 137Cs gives sediment accretion rates resembling those obtained from trace metals and 210Pb. The period of the highest sediment accumulation rate could be related to the highest loads of effluent from the iron smelter and city of Cz?stochowa, which were substantially reduced after the construction of effluent treatment plant. 相似文献
199.
Turski MP Kamiński P Zgrajka W Turska M Turski WA 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):17-23
Kynurenic acid (KYNA) is a metabolite of tryptophan which is formed along the kynurenine pathway. KYNA may possess neuroprotective,
anti-inflammatory, antioxidant and antiproliferative properties. This study measured the concentration of KYNA in various
varieties of potatoes and products made from potatoes. KYNA content was determined by means of the high-performance liquid
chromatography with fluorescence detection. KYNA was found in all 16 studied varieties of potato tubers in amounts varying
from 0.239 to 3.240 μg/g dry weight. The content of KYNA in potato tubers declined during long-term storage. The content of
KYNA in French fries varied from 0.100 to 0.646 μg/g dry weight. KYNA content in potato crisps was 0.478 and 0.576 μg/g dry
weight. Hence, all in all, we concluded that the amount of KYNA potentially delivered to the human body in potatoes and various
foods produced from potatoes is high and might be compared to the amount of KYNA present in a maximum daily dose of popular
herbs and herbal medicines. 相似文献