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1.
To advance our understanding of the effects of inoculation with ectomycorrhizal fungi (EMF) on seedling colonization in mine wastelands, we conducted a field experiment in a copper tailing. Six-month-old seedlings of Japanese red pine (Pinus densiflora) and oak (Quercus variabilis) separately inoculated with three EMF species (Pisolithus sp., Cenococcum geophilum, Laccaria laccata) were transplanted to the copper tailing. The survival rates of tree seedlings were monitored monthly, and growth (biomass and height), contents of nutrients and heavy metals (K, P, Ca, Mg, Cu, Zn), and mycorrhizal infection rates of seedlings were determined 6 months after planting. Oak seedlings exhibited higher survival rates than pine seedlings after 6 months of growth on the tailing. EMF inoculations of pine seedlings significantly enhanced their survival, growth, and nutrient uptake. In contrast, EMF inoculations of oak seedlings improved growth only in terms of biomass. Additionally, EMF inoculation caused pine seedlings to accumulate more Cu and Zn in roots compared to non-inoculated seedlings, whereas inoculation inhibited the accumulation of heavy metals in shoots. However, similar results were not observed in oak seedlings. Observations of roots indicated that the rates of mycorrhizal infection of both tree species had dramatically declined at harvest time. In conclusion, ectomycorrhizal symbioses can improve the survival and performance of pine seedlings in mine tailings. The present study provided direct evidence of the importance of EMF inoculation of seedlings to the reforestation of mine wastelands.  相似文献   
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Uncertainties in the assessment of critical loads for acidic deposition are caused by the choice of biological indicators (BI), critical chemical values (CCV), the current methods used to determine critical loads for an ecosystem, and deficient field data. This paper focuses on the present steady-state mass balance (SSMB) approach, dynamic models and the importance of changes in atmospheric base-cation deposition (BCD), particularly in China. It is argued that 1) for the SSMB approach much uncertainty may come from the choice of BI and the related CCV, and long-term and large-scale monitoring data on weathering rates and growth uptake are urgently needed, especially in China, 2) significant uncertainty may be caused by changes in BCD during SO2 emission controls, particularly in China, 3) constructing a mechanistic Al submodel may be a promising direction for dynamic models, and 4) the nutrient cycle in the vegetation through biogeochemical processes should be incorporated into dynamic models but the input requirements should be moderate for broad application considerations. Generally higher BCD, different soil components and characteristics and different vegetation types in China compared to Europe and North America suggest that more field investigations on BI and their corresponding CCV be carried out before application of current approaches to specific areas, particularly in China.  相似文献   
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The geographical and temporal variations of chemical constituents in winter precipitation collected in the areas along the coast of the Sea of Japan (AASJ) were discussed by analyzing the data obtained in the 1st and 2nd National Acid Deposition Survey by Japan Environmental Laboratories Association. In western Tohoku (WT) and Hokuriku (HR) areas in AASJ, in spite of large amounts of precipitation in winter, concentrations of non sea salt (nss-)SO4 2? are not as low as the other areas, and nss-Ca2+ in these areas is lower than the other areas. As a result, H+ concentrations of precipitation in these areas are somewhat higher than other areas. From the temporal analysis of daily sampled data and back trajectory analysis of air mass, it was found that the concentrations of nss-SO4 2?, NO3 ?, NH4 + and nss-Ca2+ are correlatively varied when air mass come from the Asian Continent, showing higher concentrations at the western sites in AASJ and depending on the meteorological conditions such as the direction of in flow air mass.  相似文献   
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The lunar surface, a key proxy for the early Earth, contains relics of asteroids and comets that have pummeled terrestrial planetary surfaces. Surviving fragments of projectiles in the lunar regolith provide a direct measure of the types and thus the sources of exogenous material delivered to the Earth-Moon system. In ancient [>3.4 billion years ago (Ga)] regolith breccias from the Apollo 16 landing site, we located mineral and lithologic relics of magnesian chondrules from chondritic impactors. These ancient impactor fragments are not nearly as diverse as those found in younger (3.4 Ga to today) regolith breccias and soils from the Moon or that presently fall as meteorites to Earth. This suggests that primitive chondritic asteroids, originating from a similar source region, were common Earth-Moon-crossing impactors during the latter stages of the basin-forming epoch.  相似文献   
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K. Rikiishi    T. Matsuura    M. Maekawa    K. Noda  K. Takeda 《Plant Breeding》2003,122(2):105-111
Eighty‐four cultivars of barley (Hordeum vulgare) and 95 wild strains (82 of H. spontaneum and 13 of H. agriocrithon) were surveyed for the production of callus, callus growth, and shoot regeneration in cultures derived from immature embryos. All cultivars except for ‘Turkey 381′, induced calli from more than 90% of embryos. On the other hand, the wild lines showed a large variation in the percentage of callus induction from 0 to 100%. Among the cultivars, those with the brittle rachis genotype, bt Bt2, on chromosome 3H, regenerated shoots with a significantly higher percentage than the cultivars with the Bt bt2 genotype. Green shoots were produced in a higher ratio (0.84) in the cultivars than in the wild lines (0.52). Among the lines examined,‘Lenins’ regenerated shoots efficiently (90.4%) and produced the highest number of calli with green shoots per embryo (4.77) followed by ‘Golden Promise’ (3.15). Examination of callus growth and shoot regeneration from embryos at different developmental stages revealed that scutellum development affected the quantity and quality of callus and shoot regeneration.  相似文献   
7.
In order to estimate dry deposition, deposition velocity calculation and concentration measurement were carried out in Niigata, Japan. Deposition velocities of SO2 and HNO3 for some surfaces such as coniferous forest, deciduous forest, agricultural land, and water were calculated taking into account diurnal variations of meteorological elements using routine meteorological data. Deposition velocities of fine and coarse aerosols were also estimated respectively. Concentrations of SO2, HNO3, sulfate and nitrate in fine and coarse aerosols respectively were measured from July to December in 1998 using filter pack and denuder methods. The results indicate that HNO3 dry deposition for the high aerodynamic roughness surfaces such as forests is quite large. It is suggested that sulfate and nitrate aerosols depositions as well as the gases depositions should be taken into account to estimate dry deposition of sulfur and nitrogen compounds. It is also indicated that dry depositions of sulfur and nitrogen compounds are unable to ignore compared with their wet depositions.  相似文献   
8.
Lingual antimicrobial peptide (LAP), one of the β-defensins in bovines, and lactoferrin (LF) are synthesized in mammary epithelium and have bactericidal and bacteriostatic functions. However, it is not known whether they have similar expression patterns. Therefore, the present study was undertaken to compare (1) immunolocalization of LAP and LF in the mammary gland and (2) changes in concentration of these two components in milk after lipopolysaccharide (LPS) challenge. Bovine mammary tissues without LPS challenge were collected and their sections were immunostained with antibodies to LAP or LF. Milk from our previous study was collected every hour up to 12h and twice daily from d 1 to 7 after LPS challenge (the day of infusion was considered as d 0). These milk samples were measured for LAP but not LF in our previous report. Therefore, concentration of LF was measured by enzyme immunoassay in the present study. Epithelial cells of some alveoli showed immunopositive reaction for LF, but negative for LAP. Conversely, some alveoli were LAP positive in their epithelial cells but LF negative. Many alveoli had immunoreactions for neither LAP nor LF. The concentration of LAP in milk was elevated significantly at 3h after LPS infusion compared with pre-infusion values and remained at a high level until 12h. However, LF concentration in milk remained low at d 0 and increased at d 2. These results suggest that LAP and LF were mostly differentially localized in the alveolar epithelium in mammary glands. The different spatial expressions between them may be associated with their different temporal expression mechanisms.  相似文献   
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