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41.
Jan Banaś Leszek Bujoczek Stanisław Zięba Marek Drozd 《European Journal of Forest Research》2014,133(6):1095-1107
In the modern forestry paradigm, many factors influence the amount of coarse woody debris (CWD). The present paper analyzes the effects of both local (national) programs (special functions of forests) and European programs (Natura 2000 sites), as well as the individual characteristics of forest stands. The study was conducted on 2,752 sampling plots distributed over an area of about 17,500 ha and located in lowland stands having a species composition typical of large areas in central Europe. Natura 2000 areas contained significantly more CWD (8.4 m3/ha) than areas not covered by the program (4.8 m3/ha). However, this is due to the fact that Natura 2000 sites involve well-preserved forest areas, such as nature reserves (26.6 m3/ha). In the managed forests that have been covered by the Natura 2000 program over the past several years, the volume of CWD has not increased. Forests with ecological and social functions differed slightly in the amount of CWD. More CWD occurred in protected animal areas (8.7 m3/ha) than in stands damaged by industry (3.9 m3/ha). Intermediate CWD levels were found in water-protection forests and in forests located around cities and military facilities. In managed forests, the lowest CWD volume was observed in middle-aged stands. The species composition of the stand had little effect on the volume of CWD. Only stands with a predominance of ash and alder had higher CWD levels (13.5 m3/ha). More CWD was found in stands whose species composition did not represent the potential site quality (6.4 m3/ha) than in habitats with the optimum species composition (3.8 m3/ha). CWD volume should be systematically increased taking into consideration local natural conditions. Such efforts should be focused on particularly valuable regions, and especially on Natura 2000 sites, where the threshold values reported from other European forests should be reached. Leaving some trees to die naturally and retaining reasonable amounts of such trees ought to be incorporated into CWD management practice in Poland. 相似文献
42.
Sylwia Goławska Iwona Sprawka Iwona Łukasik Artur Goławski 《Journal of pest science》2014,87(1):173-180
The effects of two polyphenolic flavonoids (flavanone naringenin and flavonol quercetin) on development, fecundity, and mortality of the pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), were determined in vitro, on an artificial diets. Also determined in vitro (DC EPG method), on sucrose–agarose gels, were the effects of flavonoids on the probing and feeding behavior of adult apterae. When added to a liquid diet, higher concentrations of studied flavonoids increased the developmental time, the pre-reproductive period, and mortality and decreased fecundity and the intrinsic rate of natural increase of A. pisum. In most events associated with stylet activity (as indicated by EPG waveform g-C), differences in probing behavior did not statistically differ between the control gel and those with flavonoids; quercetin at 10, 100, and 1,000 µg cm?3 prolonged the number of gel penetrations; and quercetin only at 10,000 μg cm?3 prolonged the time the first g-C waveform was observed. Addition of flavonoids to the gels generally reduced passive ingestion from fluids of the gels (EPG waveform g-E2). At higher concentrations (>1,000 µg cm?3) the flavonoids completely stopped salivation (EPG waveform g-E1) and passive ingestion from fluids of the gels (EPG waveform g-E2). In events associated with active ingestion (EPG waveform g-G), however, differences in feeding behavior did not statistically differ between the control gel and those with flavonoids. The present findings demonstrate detrimental effects of the flavanone naringenin and flavonol on the behavior of the pea aphid. This can be employed in a biotechnological projects for plant breeding resistant to herbivores, including aphids. 相似文献
43.
K. Bieniarz P. Epler W. Popek R. Billard M. Sokołowska 《Fish physiology and biochemistry》1986,2(1-4):109-114
Effects of pimozide (Pim) and [(D-Ala6, Pro9-NEt) LHRH] (LRH-Aa) on common carp oocytes maturation and ovulationin vivo under laboratory and commercial fisheries farm conditions were investigated.Although injections of Pim and LRH-Aa at the doses of 10 mg and 50 µg/kg body weight respectively, did not increase mGtH levels (66.7–155.8 mg/ml) as much as injections of carp pituitary extract (chh) (382.1 ng/ml), induced GtH levels were high enough to induce ovulation. Changes in the ovary caused by Pim and LRH-Aa were similar to those induced by chh, and Pim injected together with LRH-Aa in a single injection gave the same results concerning ovulation induction as when they were applied separately at 6h interval. 相似文献
44.
Radioimmunology was used to determine leptin and ghrelin levels in sow colostrum and milk in relation to those in sow and neonatal pig blood plasma and to the body weight of piglets during the first week of lactation. The highest concentration of leptin was found in colostrum on the second day of lactation (69.3 ± 6.3 ng/mL). Leptin concentrations in sow plasma were significantly lower than in colostrum/milk (2.19 ± 0.9 ng/mL, P = 0.7692) and were stable in the first 7 days of lactation. Total and active ghrelin concentrations in colostrum/milk were stable in the measured time points (6734 ± 261 pg/mL, P = 0.3397; 831 ± 242 pg/mL, P = 0.3988, respectively). Total ghrelin concentrations in sow plasma were lower than in colostrum/milk. These results indicate that pigs follow a unique species‐specific pattern of leptin and ghrelin synthesis, release and existence, and that the mammary gland is an important source of leptin and ghrelin contained in colostrum/milk. 相似文献
45.
Sławomir Wróbel 《American Journal of Potato Research》2014,91(6):706-713
The impact of a dozen mixtures of the most commonly applied aphicides: Mospilan 20 SP (acetamiprid), Pirimor 500 (pirimicarb) and Karate Zeon 050 CS (lambda-cyhalothrin), combined with the mineral oil Sunspray 850 EC, was researched in field conditions to assess their effectiveness in limiting potato tuber PVY, PVM and PLRV infection. In spite of the greatest reduction in the number of aphids occurring following application of Mospilan 20 SP, this treatment was not as effective in limiting PVY infection as, for example, applying Sunspray 850 EC mineral oil. Mineral oil, when used on its own or in a mixture with Pirimor 500 WG, was found to be the most effective measure for limiting PVY infection (the incidence of tubers infested with PVY was reduced by 64 % relative to control, i.e. no protection). A slightly weaker effect was observed in the case of a combination of the mineral oil with full doses of Karate Zeon 050 CS with a half of a dose of Mospilan 20 SP insecticide, however only for protection against PVY. A similar trend was observed for PVM even though a significant difference was only observed for Sunspray 850EC?+?Pirimor 500WG. In conclusion, the application of insecticide mixtures with mineral oil in protecting against PVY infection is not always as effective as the application of the oil itself only. Addition of the insecticide may sometimes improve the efficacy of protection, however, due to the extra costs involved, not always does it have to be economical. 相似文献
46.
Joanna Sobczyk Piotr Frączek Michał Obarzanowski Julio M. del Hoyo-Meléndez Łukasz Bratasz 《Wood Science and Technology》2014,48(5):981-994
Consolidation treatments are commonly employed in museum conservation studios for treating biologically deteriorated wooden cultural heritage objects. Impregnation using either a solvent/resin or a polymerizing system is an example of such an intervention, which is often difficult to describe in terms of its behavior within the object’s structure. A new simple method has been devised to evaluate the effectiveness of these impregnation treatments in terms of spatial distribution of consolidant solution. A combination of digital radiography and imaging analysis has permitted to evaluate the degree of penetration of a consolidant and to determine its location within the artifact by studying the X-ray images taken before, during, and after treatment. The adequacy of polymer solutions or their effectiveness as wood consolidants is properties which are often difficult to investigate due to limited visual access to the interior of the object. The proposed method provides an alternative way of studying these parameters through analysis of X-ray attenuation recorded on two images: taken before and after the conservation treatment. The resulting image is then converted into a two-dimensional map of consolidation agent within the object using a straightforward calibration procedure. 相似文献
47.
PPR‐B‐31: a new maintainer allele in the male‐fertility restorer gene of radish (Raphanus sativus) Ogura cytoplasm 下载免费PDF全文
Anna Hawliczek‐Strulak Grzegorz Bartoszewski Renata Słomnicka Aleksandra Korzeniewska Régine Delourme Iwona Bartkowiak‐Broda Katarzyna Niemirowicz‐Szczytt 《Plant Breeding》2015,134(5):557-563
The PPR‐B gene is responsible for male‐fertility restoration of the Ogura‐type male‐sterile radish plants, and it is located in the complex Rfo locus in the vicinity of similar PPR‐A gene and PPR‐C pseudogene. The aim of this study was to identify PPR‐B alleles and understand the structure of the Rfo locus in radish breeding lines. Five lines of radish with normal male‐fertile cytoplasm were tested. The entire PPR‐B gene was amplified, sequenced and allelic PPR‐B sequences were identified. The results indicated that the maintainer lines 7, 15 and 21 contained a non‐restoring form of PPR‐B protein. A unique PPR‐B was found in lines 24/15 and 31 that are restorer and maintainer lines, respectively. The substitutions might be responsible for the loss of a restoring function of the PPR‐B‐31 allele. Amplification of the PPR‐A/PPR‐B and PPR‐B/PPR‐C intergenic regions allowed to identify rearrangements within Rfo locus. Obtained results confirm the wide allelic variation within the Rfo locus, as well as high genetic complexity of the fertility restoration mechanism in radish. 相似文献
48.
Przemysław Barłóg 《Journal of plant nutrition》2016,39(1):1-16
High yield of sugar beet require adequate mineral nutrition. To be diagnosed across interacting nutrients using appropriate interpretation models, the plant must be sampled at a critical physiological stage. This study aimed to develop and validate norms at the 7-leaf and well-developed rosette stages, for diagnostic purposes using the Diagnosis and Recommended Integrated System (DRIS) and Compositional Nutrient Diagnosis based on centered log ratios (CND-clr). Data on nutrient concentrations and plant performance were obtained from 409 plots in West-Central Poland. With respect to the growth stages, for physiological and practical reasons, the 7-leaf stage is preferable for diagnostic purposes. At this growth stage, the high-yield subpopulation characterized by higher concentration of potassium and sodium compared to other nutrients. CND-clr indices were closely related to DRIS indices (R2 > 0.93). The CND-clr indices, however, better explained the differences in the white sugar yield within the validated dataset than the DRIS indices. 相似文献
49.
Krzaklewski W. Barszcz J. Małek S. kozioł K. Pietrzykowski M. 《Water, air, and soil pollution》2004,159(1):151-164
In the technological processes of ore flotation in the non-ferrous metal industry flotation, tailings constitute up to 98% of the total of the processed material. They are stored in sedimentation ponds as fine-grained drift containing an excess of heavy metals, mainly zinc, cadmium, lead and copper. After the dehydration and drying up of the surface of sedimentation ponds, these metals are carried with dust by the wind and they are accumulated in the vicinity of the ponds in humus horizons of soils causing considerable degradation and even devastation. In this publication, we have presented the results of research on the negative influence of such a structure on the soils of an adjacent fragment of forest and its dependence on the distance from the sedimentation pond. The level of degradation of the soils under research has been assessed on the basis of changes and transformations of the morphological soil profiles, the level of alkalization and accumulation of heavy metals (Zn, Pb, Cd) in the topsoil layers and their translocation in the soil horizons. The following soils have been distinguished in the investigated area: Haplic Podzols distorted and degraded as well as Urbic Anthrosols. The acquired results have served to depict the spatial accumulation of these heavy metals in the topsoil layers. The highest accumulation of heavy metals and the degradation of the forest sites connected with it has occurred in the vicinity of a sedimentation pond drain channel. Soil remediation has been recommended in this area. 相似文献
50.
Bogumił Rychcik Jadwiga Wierzbowska Milena Kaźmierczak-Pietkiewicz Arkadiusz Światły 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(4):349-359
ABSTRACTThe content of macronutrients in potato tubers arouses interest because of their substantial consumption in the world and significant role in elements' budget in human diet. The research objective has been to evaluate the content of macronutrients in tubers of potatoes grown in different systems of crop production in Poland. In 2012–2014, an experiment was conducted to test potato cultivation in three-crop production systems: conventional, integrated and organic. In each of the six-field crop rotation systems, there were five potato cultivars classified into different earliness groups. The following macronutrients in dry mass of potato tubers were determined: N, P, K, Ca, Mg, Na, S and Cl, and the various ratios between them were calculated. The research carried out proved that potatoes production systems affect the chemical composition of tubers, which is additionally modified by whether condition and genetic features of cultivars. Potato tubers from organic farming contained by about 20% less N than tubers from conventional or integrated systems. Potato tubers from organic production system displayed lower content of Ca and Na in comparison with the conventional and integrated systems. The least of P and S were detected in tubers of the potatoes grown conventionally. 相似文献