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971.
Marmett Bruna Carvalho Roseana Böek Dorneles Gilson Pires da Silva Igor Martins Romão Pedro Roosevelt Torres Nunes Ramiro Barcos Rhoden Cláudia Ramos 《Environmental science and pollution research international》2020,27(31):39019-39028
Environmental Science and Pollution Research - Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled... 相似文献
972.
Umar Ibrahim Khalil Nourani Vahid Gökçekuş Hüseyin 《Environmental science and pollution research international》2021,28(36):49663-49677
Environmental Science and Pollution Research - Accuracy in the prediction of the particulate matter (PM2.5 and PM10) concentration in the atmosphere is essential for both its monitoring and... 相似文献
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L. A. König 《Die Naturwissenschaften》1986,73(11):651-654
978.
Fritz Trillmich 《Behavioral ecology and sociobiology》1986,19(3):157-164
Summary Maternal investment and sex-allocation were measured in a large, sexually dimorphic mammal, the Galapagos fur seal (Arctocephalus galapagoensis). The sex ratio at birth was 1.06. Males were always heavier than females and, at least initially, grew faster. Growth was variable from year to year suggesting energetic constraints on maternal investment. Sucking time conrrelated with milk intake. Mothers suckled yearling and 2-year-old sons more than daughters of the same age. Age at weaning appeared to be the same in both sexes or even slightly greater in males. No sex differences was found in mortality prior to weaning or in post-weaning dispersal. Birth rates of females with yearlings or 2-year-olds were significantly lower than those of females with no dependent young. Mothers invested more in sons than in daughters until weaning. It is unlikely that higher post-weaning investment in daughters balances the higher pre-weaning investment in sons. Data on sex ratio at birth, different growth rates, and weaning age of the sexes are typical of otariid seals as a group. The results of this study fit Maynard Smith's (1980) model of the evolution of sex allocation better than Fisher's (1930). 相似文献
979.
980.
Christian Huber Manuela Baumgarten Axel Göttlein Verena Rotter 《Water, Air, & Soil Pollution: Focus》2004,4(2-3):391-414
More than 85% of the mountainous spruce forest of the Bavarian Forest National Park died after bark beetle attack during the last decade. The elemental budget of intact stands and of different stages after the dieback was investigated. N-fluxes in throughfall of intact stands were lower (12–16 kg ha-1 a-1) than in an earlier study in an intact mountainous spruce stand in the Bavarian Forest National Park and were reduced in the first years after the dieback (3–5 kg N ha-1 a-1). Nitrate-N fluxes by seepage water of intact stands at 40 cm depth, which is below the main rooting zone, were moderate (5–9 kg ha-1 a-1). After the dieback of the stands, NH4 + concentrations were increased in humus efflux as were NO3 - concentrations in mineral soil. Due to the relatively high precipitation, dilution of the elemental concentrations in seepage was considerable.Therefore, NO3 - concentrations were usually below the level of drinking water (806 μmol NO3 - L-1), with lowest concentrations after the snowmelt and highest in autumn. Nitrate concentrations were elevated from the first year until the 7th year after the dieback. Total NO3 --N losses by seepage until the 7th year after the dieback equalled 543 kg N ha-1. Aluminium fluxesafter the dieback were enhanced in the mineral soil from 55 to 503 mmolc m-2 a-1 (average of 8 yr), K+ fluxes from 8 to 37 mmolc m-2 a-1, and Mg2+ fluxes from 13 to 35 mmolc m-2 a-1. The consequences for the nutritional status of the ecosystem, the hydrosphere, and forest management are discussed in the paper. 相似文献