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81.
Viša Tasić Renata Kovačević Biljana Maluckov Tatjana Apostolovski – Trujić Branislava Matić Mira Cocić Mirjana Šteharnik 《Water, air, and soil pollution》2017,228(6):230
The content of As and heavy metals (Pb, Cd, Ni, and Cu) in total suspended particulate (TSP) and PM10 at 3 locations (Park, Institute, and Jugopetrol) near the copper smelter in Bor (Serbia) has been analyzed within the period 2004 to 2015 with the aim of investigating the seasonal and spatial changes of those pollutants in the suspended particles. The content of As in TSP and PM10 was over the annual EU limit value at all measuring points during the entire period of observation, while contents of Cd and Pb were periodically above the annual EU limits. There were no statistically significant seasonal changes between mean levels of the observed elements in the cold (October–March) and warm (April–September) periods during the year. A strong and moderate positive correlation was detected between the concentrations of each particular element (except Ni) at all measuring points. Additionally, Cd was the most enriched element followed by Pb, As, and Cu, while Ni was low-enriched. The constant air pollution with As particles, sometimes in concentrations even 20 times higher than the permitted annual value, requires urgent undertaking of concrete actions in order to reduce anthropogenic emission of suspended particles in Bor. 相似文献
82.
Josef S. Berger Klaus Birkhofer Helena I. Hanson Katarina Hedlund 《Journal of pest science》2018,91(3):1093-1105
It is crucial to consider the effects of large-scale drivers on species presences and ecological interactions to understand what structures communities. In our study, we investigated how the species composition and the potential interaction networks of herbivore and parasitoid communities in oilseed rape fields are affected by agricultural landscape characteristics. Insect communities of 26 winter oilseed rape fields in southern Sweden were captured in water traps over a continuous time span of 30 ± 2 days. In total, 31% of the variation in the composition of herbivore host communities was explained by a combination of the surrounding oilseed rape area in the study year and the previous year and distance to the nearest forest. The oilseed rape area in the study year and distance to forest also explained 14% of the variation in the composition of parasitoid communities. Distance to the nearest forest together with the area of oilseed rape in the previous year explained 45% of the variation in asymmetry of interaction webs. These results indicate that several measures of landscape configuration are important both for the composition of host and parasitoid communities and also for the structure of interaction networks. Our results support the view that it is an appropriate strategy to cultivate oilseed rape in landscapes that are far away from forests, in order to minimize recolonization by pest species and at the same time to attract parasitoid species from the open landscape. 相似文献
83.
Jožica Gričar Martin Zupančič Katarina Čufar Primož Oven 《Wood Science and Technology》2007,41(6):463-475
The effect of heating (23–25°C) and cooling (9–11°C) on regular cambial activity and xylem and phloem formation in the stem
portion of Norway spruce was investigated. Adult trees were sampled at 21-day intervals during the 2005 vegetation period.
Continuously elevated temperatures increased the rate of cell division in the first part of the growing season, but did not
significantly prolong cambial activity at the end of the vegetation period in the heated tree. Low-temperature treatments
shortened regular cambial activity and slowed down cell production. The xylem growth ring was wider in the heated sample and
narrower in the cooled sample compared to the control. The temperature in the cambial region was only negligibly transferred
along the stem from the site of its application. In general, the temperature in the cambium was affected by a long-term rise
or drop in air temperatures. Both experiments affected the structure and width of phloem growth increments. The tangential
band of the axial parenchyma was not continuous in the cooled sample. The number of late phloem cells was reduced in the cool-treated
sample and increased in the heat-treated sample. Our experiments confirmed the effect of constantly increased or decreased
temperatures on regular cambial activity in Norway spruce. 相似文献
84.
The aim of this study was to investigate antioxidant capacity of nine Fabaceae species collected on the mountains of Serbia and Montenegro. Antioxidant assays with various reaction mechanisms were used, including total phenolic content by Folin-Ciocalteu, DPPH radical scavenging capacity, Trolox equivalent antioxidant capacity (TEAC) values by ABTS radical cation and inhibition of liposome peroxidation. The investigated plants exhibited strong antioxidant capacity in all the tested methods, and among them, Lathyrus binatus, Trifolium pannonicum, and Anthyllis aurea were found to be the most active. 相似文献
85.
Doughty Katarina H. Garner Shawn R. Bernards Mark A. Heath John W. Neff Bryan D. 《International Aquatic Research》2019,11(4):325-334
International Aquatic Research - There is considerable interest in developing diets that maintain growth performance and market appeal for salmon aquaculture while relying less on fishmeal as a... 相似文献
86.
There is little information concerning N2O fluxes in the pasture soil that has received large amounts of nutrients, such as urine and dung, for several years. The
aims of this study were to (1) experimentally quantify the relationship between mineral N input and N2O emissions from denitrification, (2) describe the time course of N2O fluxes resulting in N inputs, and (3) find whether there exists an upper limit of the amount of nitrogen escaping the soil
in the form of N2O. The study site was a grassland used as a cattle overwintering area. It was amended with KNO3 and glucose corresponding to 10–1,500 kg N and C per hectare, covering the range of nutrient inputs occurring in real field
conditions. Using manual permanent chambers, N2O fluxes from the soil were monitored for several days after the amendments. The peak N2O emissions were up to 94 mg N2O–N m−2 h−1, 5–8 h after amendment. No upper limit of N2O emissions was detected as the emissions were directly related to the dose of nutrients in the whole range of amendments
used, but the fluxes reflected the soil and environmental conditions, too. Thus, in three different experiments performed
during the season, the total cumulative losses of N2O–N ranged from 0.2 to 5.6% of the applied 500kg ha−1. Splitting of high nutrient doses lowered the rate of N2O fluxes after the first amendment, but the effect of splitting on the total amount of N2O–N released from the soil was insignificant, as the initial lower values of emissions in the split variants were compensated
for by a longer duration of gas fluxes. The results suggest that the cattle-impacted soil has the potential to metabolize
large inputs of mineral nitrogen over short periods (∼days). Also, the emission factors for did not exceed values reported in literature. 相似文献
87.
Measuring shear stress relaxation with an established research rheometer after slowly applying large strain proved useful for characterizing the effects of different chemical and enzymatic additives. Baking tests done with and without added ascorbic acid indicated that the method can be used for predicting effects of such additives on breadbaking quality. The relaxation process for dough is discussed in terms of two flow processes, one occurring at short time periods and the other at longer time periods. The slowly applied large strain shear stress relaxation method provides information about stress relaxation behavior during the second flow process. The effects of two enzymes (protease and glucose oxidase) and two chemical additives (ascorbic acid and potassium bromate) were studied. The results are presented as the stress relaxation curve with the corresponding rate plot and the initial value of the stress. Addition of the oxidizing agents increased the second flow process times and decreased the relaxation rate during the second process. Protease shortened the second flow process times and increased the relaxation rate during the second process. Glucose oxidase separated the two flow processes by increasing the relaxation time of the second process and decreasing the relaxation time of the first process. 相似文献
88.
Vida Skrabanja Ivan Kreft Terezija Golob Mateja Modic Sayoko Ikeda Kiyokazu Ikeda Samo Kreft Giovanni Bonafaccia Martina Knapp Katarina Kosmelj 《Cereal Chemistry》2004,81(2):172-176
Buckwheat seeds (Fagopyrum esculentum Moench) were milled into 23 fractions: seven fine flours, three coarse flours, four small semolina, two big semolina, six bran, and one husk fraction. A considerable variation in gross chemical composition was found among the milling fractions. The protein content varied from 4.4 to 11.9% (db) in flours and from 19.2 to 31.3% in bran fractions; starch varied from 91.7 to 70.4% in flours and from 42.6 to 20.3 in bran. The percentage of soluble dietary fiber contained in total dietary fiber was higher in flours than in semolina and bran fractions. Ash, Fe, P, tannin, phytate content, and color were also investigated. A unique distribution of phytate was found in starch. Correlation is significantly positive in husk, bran, and semolina fractions, while correlation is significantly negative in flour fractions. Depending on technological or nutritional demands, appropriate fractions may be chosen to achieve the desired end‐use product. 相似文献
89.
Renata Bažok Jasminka Igrc Barèiæ Tomislav Kos Tanja Gotlin Èuljak Martina Šiloviæ Siniša Jelovèan Antonela Kozina 《Journal of pest science》2009,82(4):311-319
The European corn borer (ECB), Ostrinia nubilalis (H?bner) (Lepidoptera: Crambidae), is the major arthropod pest of corn in Croatia. However, chemical control is carried out only in maize for seed production, and in sweet corn. A 3-year investigation was carried out in corn fields in northwest Croatia to establish the most attractive pheromone lure for ECB monitoring, the optimal timing of insecticide applications, and the efficacy of selected insecticides against ECB. During each of the 3 years, the pheromone lures E, Z and E/Z («Isagro») were evaluated in the field from May to July. Insecticides were sprayed 14–20 days after the maximal capture in 2002 and 2003. In 2004, three different trials were set up: one trial with one early treatment (when corn was in the R49 development stage according to the extended BBCH scale); one with one late treatment (when corn was in the R65 development stage according to the BBCH scale); and one with two treatments in both stages. In the trials studying Bacillus thuringiensis var. kurstaki (B.t.k.), insect growth regulators (IGR), spinosad and classical chemical insecticides were applied. Pheromone lure E was the most attractive for monitoring ECB flights throughout 2 years of investigation. Insecticide efficacy depended on application timing. The insecticides most suitable for integrated pest management (IPM) programs, including spinosad, B.t.k. and IGR, resulted in high (spinosad) to moderate (B.t.k.) efficacy. The efficacy of IGRs indicates the need for earlier application. The efficacy of chemical insecticides depended on the year and the insecticide. The organophosphate (OP) insecticides and pyrethroids gave moderate to good results; imidacloprid did not provide significant efficacy. One application of all insecticides based on proper (early) timing resulted in the same efficacy as two applications of the same insecticides. 相似文献
90.
Franka Brüchert Muhidin Šeho Ulrich Kohnle 《European Journal of Forest Research》2017,136(5-6):957-969
Bark wounds by damage during harvesting are a serious problem in forestry due to fungi infection and wood deterioration. This paper presents results of an investigation about the influence of the wounds on the internal structure of such injured stems. In an experiment, bark wounds were artificially created at the stem base of Norway spruce [Picea abies (L.) Karst.] and silver fir (Abies alba Mill.). 2 years later, the injured stems along with undamaged controls were cut and the trunk portion below breast height subjected to computer tomographic (CT) analysis. Analysis of the CT-images revealed a substantial impact of wounding on sapwood properties in spruce: directly adjacent to the wound surface in all examined trees, a large disturbance zone was detected affecting on average 17% of the potential sapwood area. With increasing distance from the wound, the size of this disturbance zone diminished, but was still detectable in all trees at breast height ca. 1 m above the bark wound. 相似文献