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61.
Viktoras Racys Midona Dapkiene Liepa Bikulciene Dalia Jankunaite Danute Vaiciukyniene 《Water, air, and soil pollution》2018,229(6):210
Nitrogen removal from wastewater is usually severely inhibited under low temperatures. The wastewater enrichment using an external carbon source has the influence on the stability and efficiency of the nitrification and denitrification processes during the biological wastewater treatment. This paper reports the results of the study where the effect of temperature and addition of an external carbon source on the efficiency of wastewater treatment process were investigated. Nitrification and denitrification rates were determined in the laboratory-scale treatment system, operating under low-temperature conditions, ranging from 6 up to 15 °C. Ethanol was used as an external carbon source. The addition of ethanol resulted in the increase during the nitrification rate at lower temperature (up to 71% at 6 °C and up to 11% at 15 °C). Similar tendency was observed during the denitrification process. Denitrification rate increased up to 81% at 6 °C and up to 10% at 15 °C, respectively. Nitrification rate was slightly higher compared to the denitrification rate. Two-variable model equations for calculation of an external carbon amount required were based on the experimental data and in order to reach desirable process rate at particular wastewater temperature were developed. The independency from wastewater temperature and the amount of loaded carbon explicit interdependence between nitrification and denitrification rates were observed. 相似文献
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Virmantas Povilaitis Sigitas Lazauskas Šarūnas Antanaitis Dalia Feizienė Virginijus Feiza Vita Tilvikienė 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(1):86-95
Purpose: The current study was aimed to analyse the occurrence of water and nitrogen stress in spring barley and estimate their effects on the crop performance under low-input and conventional management.Materials and methods: Field experiments were conducted during 2007–2009 at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry on a sandy-loam soil. The management systems were: (a) conventional, with the application of fertilizers and pesticides adjusted to target 5 t ha?1 grain yield; and (b) low-input, without fertilizers and pesticides. Biomass and nitrogen concentration, leaf area index, soil moisture, drainage water runoff and ground water table were measured periodically during the growing season.Results: In all three experimental years, the annual precipitation was close or above the climate normal, but a large part of the rainfall (up to 310 mm) was lost through drainage contributing to the occurrence of temporary moisture deficit in late spring or summer. Water stress resulted in a lower spring barley biomass accumulation rate and lower biomass yield in the years characterized by sub-optimal rainfall distribution. Direct measurements of water retention in the soil and DSSAT model simulations gave relatively good indication of water stress occurrence. Under the low-input management, nitrogen nutrition level was a major constraint for spring barley biomass and grain yield formation.Conclusions: Under Central Lithuania’s conditions, spring barley frequently experiences temporary water stress, because a relatively high proportion of annual precipitation is lost during the non-growing period. This crop can benefit from anticipated increased precipitation and carbon dioxide levels if adequately provided with nitrogen. 相似文献
63.
Berlin D Nasereddin A Azmi K Ereqat S Abdeen Z Baneth G 《Veterinary parasitology》2010,174(3-4):317-322
An outbreak of trypanosomoasis caused by Trypanosoma evansi involving horses, camels and donkeys occurred in a farm in Israel. A longitudinal study of two outbreak phases was conducted which included clinical monitoring, blood smears, packed cell volume (PCV), serology and polymerase chain reaction (PCR) followed by reverse dot blot (RDB) for the molecular detection of infection. This was the first reported T. evansi outbreak in domestic animals in Israel. Most of the camels on the farm (8/10; 80%) were diagnosed with T. evansi infection whereas infection was less prevalent in the horses (3/7; 43%) and donkeys (6/13; 46%). Clinical disease was evident in 4 camels and 1 horse exhibiting characteristic clinical signs, anemia and parasitemia detected on blood smears and by positive RDB. Six other animals were diagnosed as asymptomatic latent carriers by positive RDB and 6 additional animals were only seropositive and were considered suspected carriers. A significant difference was found in the mean PCV between symptomatic and latent carriers with severe anemia observed only in the symptomatic animals. An anaphylactic-like reaction, fatal in one case, was observed in 2 camels diagnosed with severe trypanosome parasitemia immediately following treatment with melarsenoxide cysteamine. Furthermore, recurrence of infection was documented in one camel 4 months post treatment. 相似文献
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Anaemia is a common pathology associated with many infectious and non-infectious diseases. The effects of haemolytic anaemia
induced by i.p. injection of phenylhydrazine (PHZ) were studied in Atlantic cod. Phenylhydrazine injection (0.3 mg kg−1) in a DMSO and saline vehicle induced a reproducible and stable anaemia reducing haematocrit, (Hct) by 62% over 3 weeks.
Controls consisted of fish injected with saline and DMSO/saline vehicle with minimal effects on Hct or whole blood haemoglobin
(Hb). Although anaemia resulted in reduced blood lactate and glucose in PHZ injected fish, there were no effects of anaemia
on blood, sodium, chloride or potassium. Similarly, there were no changes in the relative proportions of leucocytes in the
blood although an increase in the number of immature erythrocytes was observed in the anaemic fish. Anaemic fish showed a
29 and 22% increase in cardiac somatic index (CSI) relative to saline and vehicle controls, respectively, although there were
no significant differences in the linear dimensions of the ventricle. Changes in cardiac somatic and ventricular somatic index
correlated positively and significantly with Hct but not with whole blood Hb concentration. Anaemic fish had significantly
reduced resting routine oxygen consumption compared with vehicle controls but were not able to increase oxygen consumption
following a bout of exhaustive exercise. Plasma lactate concentrations increased significantly after exercise to a greater
extent in anaemic fish compared with vehicle control fish. Phenylhydrazine is a useful model for studying haemolytic anaemia
in Atlantic cod with minimal effects on blood biochemistry and haematology and clearly reduces the aerobic capacity in Atlantic
cod. 相似文献
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Muhammad Ayaz Urte Stulpinaite Dalia Feiziene Vita Tilvikiene Kashif Akthar Edita Baltrėnaitė-Gedienė Nerijus Striugas Urooj Rehmani Sahib Alam Rashid Iqbal Monika Toleikiene Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321
Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha−1) with N fertilizer (180 kg ha−1) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg2+ by 11%, P by 4%, K+ by 50%, and Ca2+ by 56% in the soil, and Mg2+ by 13%, P by 69%, K+ by 29, and Ca2+ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12th to 62nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development. 相似文献