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31.
The behaviour of the endoparasitic tracheal mite, Acarapis woodi (Rennie) on honey bees (Apis mellifera L.) is a challenge to observe because of its small size. Through a microscope, we videotaped this mite's movement on young bees, dead bees and bees exposed to vegetable oil. Previous studies have shown that solid vegetable oil decreases mite infestations in a bee colony. We hypothesized that the oil alters mite behaviour to the detriment of the parasite, thus helping to safeguard the host. Habitat-seeking behaviour, identified as necessary for mites to locate a new host environment, was disrupted on both dead and oil-treated bees. Questing behaviour, which is associated with transfer between hosts, increased significantly on the dead and oily bees. The behaviours of mites were significantly different between all three treatments (x
2=494.96, p<0.001 on dead bees and x
2=851.11, p<0.001 on oily bees). Both questing and seeking behaviours were significantly different on each of the thoracic treatments (F
2,66=7.88, p<0.001 and F
2,66=21.28, p<0.001) and mite questing behaviour was not altered between males and females on live or oily bees (F
1,22=0.25, p<0.62), but habitat seeking was (F
1,22=7.42, p<0.012). The male questing and habitat-seeking behaviours were observed. We conclude that oil-treated bees gained protection from habitat-seeking mites because the normal behaviour of the mites seeking an oviposition site is interrupted. 相似文献
32.
T. Murphy A. Moller H. Brouwer 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1995,4(3):195-203
To enhance the biodegradation of organic contaminants, approximately 18.5 tonnes of oxidant (calcium nitrate) and 5 tonnes of nutrients were injected into sediments of the Dofasco Boatslip, Hamilton Harbour. In the laboratory 78% and 68% of the oil (TPHs) and polynuclear aromatic hydrocarbons (PAHs), respectively biodegraded in 197 days. In the 1992 treatment in the Ddofasco Boatslip, biodegradation of organic contaminants varied from 79% for low molecular weight compounds (BTXs), to 25/15 of the 16 priority pollutant PAHs. At first biodegraduation of large molecular weight PAHs resulted in the production of naphthalene (from 280 g/g to 549 g/g). In the 1993 treatments, 94% of the naphthalene, and 57% of the TPHs biodegraded. The in situ biotreatment of organic contamination takes time but for some sites the significantly lower cost relative to dredging and confinement makes in situ treatment a viable alternative. 相似文献
33.
精制蚕蛹油中碱液和过氧化值的控制 总被引:1,自引:0,他引:1
作者采用碱皂化的方法来达到精炼蚕蛹油的目的。实验表明,碱的浓度以10% ̄13%比较合适,超碱量必须视酸值大小,通过小样试验来确定。精制油的过氧化值与皂化后中性油的洗涤温度、洗涤次数及搅拌速度有密切关系,必须严格控制。 相似文献
34.
35.
Pavol Mrtonfi Anton Grejtovský Miroslav Rep
k 《Biochemical Systematics and Ecology》1994,22(8):819-825
Relationships between soil chemistry and population chemotype structure of Thymus pulegioides have been studied. The analysis of correlations suggest that an increased carbonate content in soil decreases the chemotype diversity of a population (as calculated by use of the Shannon index): the proportion of linalool chemotype plants rises and that of the phenol chemotype plants declines. In addition, the chemotype diversity decreases with increasing frequency of linalool chemotype, and increases with increase of carvacrol chemotype. 相似文献
36.
On June 26,1989, the tanker World Prodigy ran aground just outside the mouth of the West Passage of Narragansett Bay, Rhode Island, USA. About 922 metric tons of No. 2 fuel oil were released into the water and drifted over a total area of about 120 sq miles. Three days after the spill only a small fraction of the oil remained.The effects on macrobenthic crustaceans within the first five weeks after the spill were studied at five stations with a varying degree of oil exposure, including one control site never reached by oil from the spill. Significant differencies between these stations were noted for total amphipod abundance, the amphipod genus Ampelisca and ostracods (retained on a 0.3 mm mesh), but not for amphipods of the genus Corophium. At the most heavily impacted station (23 µg oil g–1 sediment dry weight), the total amphipod abundance, dominated by Ampelisca verrilli, decreased by 86% within the first two weeks after the spill. Decreases in total amphipod abundance significantly larger than at the control site were noted also at two other stations, one of which with only trace amounts of oil detected in the sediment. The amphipod populations at these sites were dominated by juvenile specimens.These findings confirm the extreme sensitivity to oil pollution of amphipods and ostracods, noted in earlier field and experimental studies. 相似文献
37.
A South African winter ephemeral D. pluvialis was exposed, under low and high nutrient conditions, to four different daily doses of biologically effective UV-B radiation. These simulated different depletions (range 0–30%) in the ozone layer at the southerly distribution limit (33° 56′S) of this species, and included daily UV-B doses received at the northerly distribution limit (26° 38′S) without ozone depletion. Growth inhibition by increased UV-B radiation was observed during early vegetative stages, but only under low nutrient conditions. Thereafter, net CO2 assimilation rate, growth and reproduction were stimulated by an increase in UV-B radiation, though doses above those approximating a 20% ozone depletion appeared to be inhibitory. Differential stimulation occurred in the two nutrient treatments. Under high nutrient conditions, photosynthesis (specifically carboxylation efficiency), and numbers of leaves, inflorescences and diaspores per plant, and leaf areas increased, but leaf thickness decreased with increased UV-B radiation. Under low nutrient conditions, dry masses of leaves, stems, inflorescences and diaspores, and total above-ground dry masses increased with increased UV-B radiation. Foliar organic carbon and nitrogen concentrations and foliar concentrations of UV-B absorbing compounds were unaffected by increased UV-B radiation, but foliar P concentrations declined. Diaspore viability declined with increased UV-B radiation. The net effect was a 35 to 43% reduction in viable diaspore production under high nutrient conditions at UV-B doses equivalent to those currently received at the northerly distribution limit during the reproductive phase. It is concluded that anticipated increases in UV-B radiation could reduce regeneration success, and seedling survival in areas of low soil fertility, particularly at lower latitudes, and consequently increase the risk of localized population extinctions from stochastic causes. 相似文献
38.
亚洲薄荷的两个化学型 总被引:2,自引:0,他引:2
周荣汉 《植物资源与环境学报》1994,3(3):58-59
亚洲薄荷的两个化学型桂新,周荣汉(安徽中医学院中药系合肥230038)(中国药科大学植物化学分类研究室南京210038)TwochemotypesofMenthaasiaficaBoriss¥ChouGui-Xin(AnhuiCollegeofTra... 相似文献
39.
本文报导了薄层层析法及高压液相色谱法定性定量地测定植物油甘油酯的组成,对不同来源的脂肪酶对植物油的水解进行了研究。实验结果表明,不同来源的脂肪酶对植物油(橄榄油)的水解性不同,同一脂肪酶水解不同种类的植物油,脂肪酶的水解率也不同,脂肪酶水解植物油有最适pH和最适温度。 相似文献
40.
石菖蒲(Acorus gramineus Soland)的精油经GC/MS/DS检测,硅胶加压柱层分离,得到一新的倍半萜,其在精油中的含量达60.30%,通过波谱方法确定了结构,并命名为石菖蒲酮(gramenone)。 相似文献