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Reforestation of degraded Kermes oak shrublands with planted pines: effects on vegetation cover, species diversity and community structure 总被引：1，自引：1，他引：0
This paper examines the results of plantings of the Mediterranean pine species, Pinus halepensis and Pinus pinea, in a degraded Mediterranean kermes oak (Quercus coccifera) shrubland in Northern Greece, which were accomplished in order to mitigate ecosystem degradation. Plant establishment and
the vegetation differences between the degraded ecosystem’s previous state and the new state following reforestation were
measured in order to evaluate the effect of reforestation. Monitoring of the seedling survival and growth of the planted species
was carried out during the next five years. In the fifth year we conducted botanical inventories in 18 and 15 plots (50 m2 in size) from the reforested and control area, respectively. Plant community parameters estimated were: vegetation composition,
total plant cover, planted species cover, native woody, herb and grass species cover, plant species richness, Shannon-Weiner
index, community structure and dominant plant height. P. halepensis exhibited higher survival and growth than P. pinea. The reforested area exhibited higher plant diversity, higher vegetation cover, taller plants and more complex community
structures than the control area, which concludes that plantings of pines can be successfully used in degraded ecosystem reforestation
projects, in areas with similar site conditions. 相似文献
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Thomas Henniger Pauline Henniger Thekla Grossmann Ottmar Distl Martin Ganter Friederike D von Loewenich 《Acta veterinaria Scandinavica》2013,55(1):38
Anaplasma phagocytophilum is a Gram-negative, obligate intracellular tick-transmitted bacterium that replicates in neutrophils. It causes tick-borne fever (TBF) in sheep and cattle, but also elicits febrile disease in humans as well as in other domestic animals such as dogs, horses, and cats. Although increasingly recognized in Europe, the first laboratory-confirmed case of TBF in cattle from Germany has been published only recently. We here present the unusual case of an intrauterine transmission of A. phagocytophilum in a calf from northern Germany. To our knowledge, this is the first report of such an event occurring under field conditions in cattle. 相似文献
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Pedohydrological properties were investigated on a piped slope in the Bergisches Land in the Rhenish Slate Mountains (Nordrhein‐Westfalen, Germany). The study confirmed that genesis and development of pipes decisively depend on hydrological conditions in the soils. Vertical water permeability of saturated samples was very high. This promoted fast seepage. Many macropores produced by earthworms also caused high transport capacity for soil water. Even more efficient were the burrows of moles and mice, enabling immediate infiltration and direct vertical and lateral water movement. On the contrary, the horizontal saturated permeability was low indicating no correlation with piping. Porosity of piped soils was not different to that of other soils of the region without pipes. 相似文献
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Despoina Varamogianni-Mamatsi Thekla I. Anastasiou Emmanouela Vernadou Nikos Papandroulakis Nicolas Kalogerakis Thanos Dailianis Manolis Mandalakis 《Marine drugs》2022,20(1)
Chronic discharge of surplus organic matter is a typical side effect of fish aquaculture, occasionally leading to coastal eutrophication and excessive phytoplankton growth. Owing to their innate filter-feeding capacity, marine sponges could mitigate environmental impact under integrated multitrophic aquaculture (IMTA) scenarios. Herein, we investigated the clearance capacity of four ubiquitous Mediterranean sponges (Agelas oroides, Axinella cannabina, Chondrosia reniformis and Sarcotragus foetidus) against three microalgal substrates with different size/motility characteristics: the nanophytoplankton Nannochloropsis sp. (~3.2 μm, nonmotile) and Isochrysis sp. (~3.8 μm, motile), as well as the diatom Phaeodactylum tricornutum (~21.7 μm, nonmotile). In vitro cleaning experiments were conducted using sponge explants in 1 L of natural seawater and applying different microalgal cell concentrations under light/dark conditions. The investigated sponges exhibited a wide range of retention efficiencies for the different phytoplankton cells, with the lowest average values found for A. cannabina (37%) and the highest for A. oroides (70%). The latter could filter up to 14.1 mL seawater per hour and gram of sponge wet weight, by retaining 100% of Isochrysis at a density of 105 cells mL−1, under darkness. Our results highlight differences in filtering capacity among sponge species and preferences for microalgal substrates with distinct size and motility traits. 相似文献
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In soils derived from loess on a range land site in the Rhenish Slate Mountains pipes were found at 120—190 cm depth above denser solifluction material. The pipes were 5—30 cm wide and 15—30 cm high. Various soil physical and chemical properties were determined and checked for their suitability as piping indicators. Silt contents reached 808 g kg—1 in the piped soil sections where bulk densities were low to medium in comparison with clay rich and denser horizons beneath. Aggregate stabilities indicated by dispersion features, percolation rates, and dispersion ratios were suitable parameters to indicate piping vulnerability. Organic carbon contents tended to be low in the piped horizons, but there was no relationship between base saturation, ESP or EC values, and piping in the investigated soils. 相似文献
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