Costel Samuil

Neophyte Invasion in Moldavia (Eastern Romania) in Different Habitat Types

The actual state of neophyte invasion in Moldavia (Eastern Romania) is described in this paper on the basis of 11,055 phytosociological relevés. We analyzed the i) proportion of relevés with neophytes, ii) mean proportion of neophytes per relevés, and iii) mean coverage of neophytes per relevé for 36 EUNIS habitat types to identify general plant invasion patterns. The level of invasion differed considerably between habitats. The invasion of neophytes especially affected habitats strongly determined or influenced by man, such as anthropogenic woodlands, ruderal habitats, arable lands or trampled areas. Most natural habitats are either slightly invaded or entirely free of neophytes. Only riverine willow stands and wet tall-herb stands are relatively highly invaded. However, the absence of neophytes in some natural habitats less represented in the phytosociological dataset could be of artifactual nature. No significant relationship between the number of neophytes and non-neophytes was found in the analysis across different habitats. When the analyses were made within-habitats, both negative and positive relationships were found, which confirm that the relationship between alien and native species richness depends on the habitats. A total number of 105 neophyte species were recorded in the phytosociological relevés used in this study. Among these, 13 species that are currently considered invasive in Moldavia occur in at least 10 types of habitats.

Reciprocal contamination by invasive plants: analysis of trade exchange between Slovakia and Romania

Abstract In this work, potential contamination by invasive plant propagules as a result of trade exchange between Slovakia and Romania, was assessed. National lists, describing biology and ecology of 30 worst invasive plant taxa, were formulated, and trading in period 2006-2010 between countries analysed. Using norms for commodity impurity level, information on species habitat occupancy and literature data dealing with seed/fruit attachment on roads we calculated then potential invasive plant propagule export (PE) for each taxon. We found three fold higher total good export from Slovakia than in opposite direction, increasing export of commodities potentially containing invasive plant propagules exported from Romania to Slovakia and rise of road compared to railway transport. PEs for Slovak invasive plant taxa were one-two orders higher than those for Romanian ones. Potentially most exported taxa for Slovakia were: Amaranthus sp., Ambrosia artemisiifolia, Galinsoga sp., Kochia scoparia and Sorghum halepense (tens to hundreds tonnes each). And these could mostly be exported from Romania: Amaranthus sp., Ambrosia artemisiifolia, Artemisia annua, Conyza canadensis, Cuscuta campestris, Datura stramonium, Erigeron annus, Galinsoga sp., Iva xanthiifolia, Kochia scoparia, Lycium barbarum, Sorghum halepense, Veronica persica and Xanthium orientale subsp. italicum (units to tens tonnes each). High PE was significantly associated with cereals export. Our formula for PE is applicable for any inter- and intra-continental trade exchange.

Symphyotrichum ciliatum in Romania: trends of spread and invaded plant communities

Abstract Symphyotrichum ciliatum was reported as invasive in Romania in the early 1970s. In this study we have analysed its invasion history, current distribution in Romania, habitat preferences and the associated plant communities. Data recorded during our recent field work, as well as from herbaria and previously published papers, were used in the analysis. This data confirms its invasive character. Given the abrupt increase in the slope of the invasion curve during the last decade, we can assume that S. ciliatum is still far from reaching the saturation phase of its invasion in Romania. Habitats invaded by this species are mostly anthropogenic herb stands associated with rail and road transport networks, and the continental inland salt steppes. The classical methodology of the Zürich- Montpellier school was used for the field phytosociological research and the classification of the investigated communities was done using the deductive method. The phytocoenoses dominated by S. ciliatum were classified as derivate communities. The description of these communities included data about plant composition, synecology and distribution in the study area.

Forage productivity of alfalfa (Medicago sativa L.) in the pedo-climatic conditions from

The research in the period 2010-2011, within the Ezareni Farm from Iasi, were focused on the influence of inoculation, fertilization and harvesting growth stage on the leaf/shoot ratio and dry matter (DM) yield, at alfalfa ( medicago sativa L.) in the second year after sowing at the first harvest. The results indicated that the interaction between inoculation, fertilization and harvesting growth stage determined increases of yield in the range of 23-110%. The control plot where fertilization was not applied, without inoculation, which was harvested at early bud registered the lowest yield, 3.21 t/ha D.M., and the biggest yield (6.72 t/ha) was registered at the plot with inoculation, fertilized with N 75 P 50, harvested at 10% blooming. The leaves/shoots ratio registered differences in the range of +11% to -42%, accordingly to the interaction between the inoculation, fertilization and harvesting growth stage. The highest leaves/shoots ratio, 0.64% was observed at the plot with inoculation, unfertilized, harvested late bloom, and the lowest leaves/shoots ratio (0.33) was observed at the plot without inoculation, fertilized with N 75 P 50 harvested at full bloom.