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Lei Yanbao Du Liushan Chen Ke Plenković-Moraj Anđelka Sun Geng 《Plant and Soil》2021,462(1-2):159-174
Plant and Soil - Nitrogen (N) and phosphorus (P) availabilities limit plant productivity, especially in primary succession; however, our understanding of species-specific strategies regarding their... 相似文献
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九寨沟县为“中国旅游强县”,区域社会经济发展与九寨沟自然保护区生态系统服务价值联系紧密。2017年,九寨沟保护区发生7.0级地震,当地生态环境和社会经济发展遭受极大创伤。基于此,分别以2016、2018年为地震前后基准年,从供给服务、调节与维持服务、文化服务3个方面选取7项指标,构建九寨沟自然保护区生态系统服务价值评价体系,探明地震前后生态系统服务价值变化。研究表明:(1)地震前后九寨沟保护区生态系统服务总价值分别为1.96×1010元/a、1.52×1010元/a,单位面积价值量达3.05×10~5元hm-2 a-1、2.36×10~5元hm-2 a-1,总降幅达22.68%。(2)地震前后三类服务价值均有所下降但价值占比序列未改变,依次为供给服务、调节与维护服务和文化服务,降幅分别为24.61%、12.25%和86.02%。(3)地震前,7项服务指标按其经济价值大小排序依次为:木材供给>水源涵养>保育土壤>森林游憩>固碳释氧&g... 相似文献
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Marija Gligora Anđelka Plenković-Moraj Koraljka Kralj István Grigorszky Danijela Peroš-Pucar 《Hydrobiologia》2007,584(1):337-346
The shallow Lake Vrana was studied over a 1-year period, special attention being paid to the phytoplankton. Phytoplankton
was investigated monthly with respect to temporal variability of selected environmental factors. The regular annual development
observed was in species contribution to total biomass rather than in seasonal changes in species composition. The assemblage
was dominated by Cosmarium tenue Arch. and Synedra sp. In winter and in spring the phytoplankton assemblage was dominated by Cosmarium tenue and high contribution of Synedra sp. was observed during the summer and autumn. Results suggest that concentrations of inorganic nitrogen and phosphorus were
critical in regulating phytoplankton biomass and species dominance. 相似文献
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Hydrobiologia - Seasonal distribution and morphological changes in two forms of Ceratium hirundinella in the shallow karstic Mediterranean lakes, Ponikve and Njivice, during 1997/98 and 2000/01,... 相似文献
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A characteristic of aquatic systems in karstic region is the formation of tufa – the product of calcium carbonate precipitation. Artificial substrata (glass slides) were used to investigate the influence of tufa deposits at two different current velocities (5 cm s–1 and 50 cm s–1) on the ciliate assemblages in periphyton. After two-month exposure periods, periphyton biomass and tufa deposit were c. three times greater at 50 cm s–1 than at 5 cm s–1. Ciliate population density was also higher on artificial substrata exposed in a lotic than in a lentic microhabitat (the overall mean number of ciliates at 5 cm s–1 was 122 ind. cm–2, and at 50 cm s–1 497 ind. cm–2). At each of the two observed current velocities, a Principal Components (PCA) ordination of the colonized ciliate associations showed a spatial separation of the associations that developed under two different conditions of tufa deposition. During the period of greater tufa deposit, associated with greater periphyton overgrowth rate, the ciliate communities had higher species diversity (a higher number of species and a lower number of individuals). Species diversity of ciliates had a positive nonlinear relation to tufa deposition rate. These results suggest that artificial surfaces covered by a rough tufa layer associated with greater periphyton biomass offer diverse conditions for colonization by ciliates. 相似文献
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Koraljka Kralj Anđelka Plenković-Moraj Marija Gligora Biserka Primc-Habdija Laszlo Šipoš 《Hydrobiologia》2006,560(1):249-258
This study determined the potential for periphyton growth on artificial surfaces using plexiglas slides exposed for different
lengths of time, orientations and depths in the lower, lentic area of River Krka during the summer of 1995. During the research
period, 88 taxa were identified. The most abundant group was Bacillariophyceae with 57 taxa. Species Cyclotella comta (Ehr.) Kutz., Achnanthidium affine (Grunow) Czarn., Cocconeis placentula Ehr. and Eolimna minima (Grunow) Lange-Bertalot were present in all samples. The results show significant differences in abundance, number and composition
of algae between growth surfaces and depths. The number of species present shows statistically significant differences with
respect to all three variables (days of colonization, depth and orientation), while the total number of cells per square centimeter
varies with respect to the days of colonization and the depth only. The highest growth potential was observed after 60 days
of exposition on the upper side of the horizontally placed surface at a depth of 1 m. During the same exposition time, the
lowest growth potential was noted on the vertical slide at a depth of 18 m. Physical and chemical parameters and their relations
to algal periphyton assemblages were also monitored. 相似文献
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