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141.
Coefficients of variation and guide values of nutrients were determined for Anthurium cultorum Birdsey cvs. ‘Baron’, ‘Choco’, ‘Pistache’, ‘President’, ‘Midori’, and ‘Tropical’ grown in expanded clay (inert medium) using drip fertigation. Fully developed leaves after freshly-cut flowers were collected as index parts for chemical analyses at two-month intervals over the period of three years (2002–2004). Investigations were conducted at two specialized commercial farms, recording optimal yielding in terms of quantity and quality. A standard nutrient solution for anthurium hydroponics was used in fertigation. Mean guide values for six analyzed cultivars of Anthurium cultorum Birdsey are (in d.m. leaves): 1.40–1.70% nitrogen (N), 0.30–0.40% phosphorus (P), 3.60–4.50% potassium (K), 1.40–1.80% calcium (Ca), 0.20–0.30% magnesium (Mg), 0.30–0.40% sulfur (S), 46.0–60.0 ppm iron (Fe), 35.0–47.0 ppm manganese (Mn), 54.0– 72.0 ppm zinc (Zn), 5.10–6.50 ppm copper (Cu), and 64.0–83.0 ppm boron (B). Guide values for cvs. ‘Baron’, ‘Choco’, ‘Pistache’, ‘President’, ‘Midori’ and ‘Tropical’ are given in the text of this paper. A diversification was shown in guide values for analyzed cultivars in relation to certain macro- and microelements. Coefficients of variation were determined for nutrient contents in index parts of plants. A very high variation (%) was found for Mn 47.5 and Zn 41.8, high for Mg 38.5, P 32.6, S 30.6, medium for Fe 29.2, Ca 28.0, Cu 23.3 and B 20.3, while low for K 11.4 and N 9.9. 相似文献
142.
Elżbieta Ziółkowska Katarzyna Ostapowicz Volker C. Radeloff Tobias Kuemmerle Agnieszka Sergiel Tomasz Zwijacz-Kozica Filip Zięba Wojciech Śmietana Nuria Selva 《Landscape Ecology》2016,31(8):1863-1882
Context
Connectivity assessments typically rely on resistance surfaces derived from habitat models, assuming that higher-quality habitat facilitates movement. This assumption remains largely untested though, and it is unlikely that the same environmental factors determine both animal movements and habitat selection, potentially biasing connectivity assessments.Objectives
We evaluated how much connectivity assessments differ when based on resistance surfaces from habitat versus movement models. In addition, we tested how sensitive connectivity assessments are with respect to the parameterization of the movement models.Methods
We parameterized maximum entropy models to predict habitat suitability, and step selection functions to derive movement models for brown bear (Ursus arctos) in the northeastern Carpathians. We compared spatial patterns and distributions of resistance values derived from those models, and locations and characteristics of potential movement corridors.Results
Brown bears preferred areas with high forest cover, close to forest edges, high topographic complexity, and with low human pressure in both habitat and movement models. However, resistance surfaces derived from the habitat models based on predictors measured at broad and medium scales tended to underestimate connectivity, as they predicted substantially higher resistance values for most of the study area, including corridors.Conclusions
Our findings highlighted that connectivity assessments should be based on movement information if available, rather than generic habitat models. However, the parameterization of movement models is important, because the type of movement events considered, and the sampling method of environmental covariates can greatly affect connectivity assessments, and hence the predicted corridors.143.
Edyta Hewelke Jan Szatyowicz Tomasz Gnatowski Ryszard Oleszczuk 《Land Degradation \u0026amp; Development》2016,27(4):955-964
An understanding of soil moisture content variability is fundamental in hydrological studies of peat soils, whose preservation depend on water‐related processes. Dehydration of fens and adapting them for agricultural production have contributed to the degradation of peat soils. The goal of this study was to determine how the critical soil moisture content (CSMC) and soil water repellency (SWR) affect soil moisture patterns in a degraded peat‐muck soil profile. SWR was measured under laboratory conditions using the water drop penetration time test, and then the CSMC was assessed. An investigation of moisture patterns was based on soil moisture data collected over short distances in a grass‐covered peat‐muck soil profile on seven dates. Observed differences in moisture patterns demonstrate that the CSMC can be used for the prediction of preferential flow occurrences in peat‐muck soils. Lower values of the CSMC and lower levels of SWR persistence in muck layers than in peat layers indicate that degradation of peat soils improves their wettability. The relatively low values of CSMC and the low shrinkage potential in the muck layer suggest that preferential water flow in the degraded organic soils can occur when heavy rains are preceded by long periods of summer drought. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
144.
Adam Tomasz Sikora Erlend Nybakk Rajat Panwar 《Scandinavian Journal of Forest Research》2016,31(1):119-125
This study examines the role of entrepreneurial orientation (EO) and learning orientation (LO) in the financial success of forest contracting firms. Both EO and LO have previously been understood to positively affect a firm's financial performance, but extant literature has not considered those links in a transition economy. Partially addressing this gap, we execute this study in a Polish context. Using data obtained through a mail survey of 101 owners of forest contracting firms (34% response rate), we found that both EO and LO have a positive and significant effect on financial performance. 相似文献
145.
The occurrence and phenotypic, and genotypic properties of 24 Staphylococcus isolates from canine dermatitis were investigated. The predominant staphylococcal species was Staphylococcus intermedius. The other species such as Staphylococcus chromogenes, Staphylococcus sciuri, Staphylococcus aureus, Staphylococcus saprophyticus, Staphylococcus epidermidis, and Staphylococcus capitis were only occasionally isolated. The study showed low level biochemical diversity among S. intermedius isolates. Resistance to antibiotics was frequently observed, with 87.5% of the isolates showing resistance to at least one drug. The most active antimicrobial agents against all staphylococci were amoxicillin/clavulanic acid, cephalexin and gentamicin. Resistance to carbenicillin, amoxicillin, ampicillin, cephadroxil, erythromycin, clinadmaycin and neomycin was common. No correlation was observed between antibiotic resistance and plasmid profile. PFGE analysis revealed a high degree of genetic polymorphism of S. intermedius, even among isolates collected in a restricted area over a short time. 相似文献
146.
147.
Borowik Tomasz Ratkiewicz Mirosław Maślanko Weronika Duda Norbert Kowalczyk Rafał 《Landscape Ecology》2020,35(6):1341-1351
Landscape Ecology - Global warming has been exerting an increasing stress on mammal populations occurring at the bioclimatic edges of their ranges. Moose, as heat-sensitive ungulates, are expected... 相似文献
148.
Tomasz Lesiow Herbert W. Ockerman Konrad Dabrowski 《Journal of the World Aquaculture Society》2009,40(5):678-686
Rainbow trout were fed a fish meal‐based diet or diets where 25, 50, 75, or 100% of the fish meal protein was replaced with a mixture of rendered animal protein ingredients. Diets were formulated to be iso‐nitrogenous (36% crude protein) and meet all known nutrient requirements of rainbow trout. The effect of five diets on dressing percentage, chemical composition, functional properties, and sensory characteristics of rainbow trout fillets stored up to 1 wk on ice in a refrigerated room (4 C) was determined. Dressing percentage based on body weight (from 724 to 811 g) did not show a significant difference due to the diet. Raw tissue pH, 24 and 144 h post mortem, were significantly lower than the control when 75 and 100% fish meal replacement were utilized. Assessment of color, texture, flavor, and tenderness indicated that fillet were lighter, less firm, more bland, and more tender after 144 h compared to 24‐h storage time. Fillets from fish fed all diets were considered as acceptable by the panel. 相似文献
149.
Kristina Raitelaityt Svetlana Markovskaja Algimantas Paulauskas Tom Hsiang Tomasz Oszako 《Forest Pathology》2020,50(2)
The presence of quarantine pathogen Lecanosticta acicola, the causal agent of brown spot needle blight, was confirmed using molecular methods for the first time in northern part of Poland on the coastal area adjacent to the Baltic Sea. This area includes sandy beaches, where Pinus mugo and P. sylvestris were planted. Symptomatic needles were collected in 2017 from 20 P. mugo trees growing in one stand in Ustka. Typical symptoms of brown spot needle blight infection, including dead needle tips and central zones with yellow or reddish brown, circular spots in green tissue, were observed on all samples. Only, the asexual stage of L. acicola was obtained during this work. The pathogen species identity was confirmed using classical morphological methods (microscopic examination of the infected needles), real‐time and species‐specific priming (SSPP) PCR, and ITS sequencing. Analysis of mating‐type (MAT) genes showed the presence of both mating types in northern Poland. 相似文献
150.
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