Search results for "Charophyt"
showing 10 items of 30 documents
Effects of overabundant nitrate and warmer temperatures on charophytes: The roles of plasticity and local adaptation
2018
Global change effects, such as warming and increases in nitrogen loading, alter vulnerable Mediterranean aquatic systems, and charophytes can be one of the most affected groups. We addressed the possible interaction between these factors on two populations of the cosmopolitan charophytes Chara hispida and Chara vulgaris. Populations were taken from two different environments, a nitrate-poor mountain lake and a nitrate-rich Mediterranean coastal spring. The laboratory experiment had a 2 × 2 factorial design based on two nitrate levels (similar to and double the local conditions) and two temperatures. Increased temperatures favoured the growth of the four populations, but an increase in nitra…
Paleoenvironmental evolution of the Pliocene Villarroya Lake, northern Spain. A multidisciplinary approach
2002
The Pliocene Villarroya basin fill consists of lacustrine and alluvial deposits over 100 m thick. The lacustrine deposits, up to 30 m thick, comprise three sequences. The two lower sequences consist of profundal, laminated deposits formed by mostly terrigenous facies that are overlain by charophytic carbonates and varves. The uppermost, third sequence made up of massive bioturbated mudstones corresponds to a very shallow lacustrine-palustrine environment. Bulk mineralogy comprises carbonates, clay minerals, quartz and feldspars. The carbonates are: exogenic, biogenic calcite and biogenic aragonite. Biogenic calcite constitutes ostracod shells and charophyte stem encrustations, whereas arago…
Preliminary palaeontological data from the Loma Negra section (Bardenas Reales de Navarra, Lower-Middle Miocene)
2013
En este trabajo se da a conocer una nueva localidad fosilífera de la Formación Tudela (Navarra). Esta formación está compuesta por facies palustres, lacustres y aluviales distales, que representan el relleno del sector occidental- central de la Cuenca del Ebro durante el Rambliense y el Aragoniense (Mioceno inferior-medio). Basado en el estudio de los restos fósiles de micromamíferos, la nueva localidad fosilífera se sitúa bioestratigráficamente en la zona D del Aragoniense. Los datos paleoecológicos obtenidos de los micromamíferos indican que el ambiente debió ser húmedo y la temperatura templada. En lo que respecta a la zona palustre, los ostrácodos, carofitas y gasterópodos definirían un…
New Species of Charophyta, Chara polyacantha A. Braun, in Lake Engure, Latvia
2012
Abstract The new charophyte species for Latvia, Chara polyacantha A. Braun, was described. This species was found in Lake Engure, the third largest lake of Latvia. In 2010, C.†polyacantha covered small, approximately 25 m2 patch, growing both in a monodominant stand and mixed with C. tomentosa in the central part of the lake.
22nd Meeting of the Group of European Charophytologists (GEC)
2019
The 22nd Meeting of the Group of European Charophytologists (GEC) was held from 17 to 21 September 2018 in Palermo. It was convened by the International Research Group on Charophytes (IRGC) and org...
The role of charophytes in a Mediterranean pond created forrestoration purposes
2015
A small, shallow basin was created and flooded with groundwater in a Reserve Area in Albufera de València Natural Park (AVNP) under the scope of a restoration program intended to mimic typical environments such as freshwater springs, abundant in the past but currently suffering from deterioration (desiccation, pollution, etc.), with the ultimate goal of increasing local biodiversity of submerged macrophytes, particularly charophytes. In this study we have monitored, from April 2009 (a few months after its first flooding) to September 2012, the dynamics of charophyte growth and related physical, chemical and biotic variables to highlight the factors determining charophyte success. Just after…
The role of Characeae in the communities of the vegetation class Potametea
2018
The stonewort vegetation is commonly classified into the phytosociological class Charetea fragilis F. Fukarek ex Krausch 1964; however, the Characeae are not exclusively found in vegetation stands ascribed to this class but also in other habitat types. In our preliminary investigations, we draw the attention to the relationship between the classes Charetea fragilis and Potametea pectinati Klika in Klika & Novák 1941 in some Sicilian biotopes. In some cases, the Charetea vegetation is ecologically and spatially distinct, although close, from that referable to the Potametea. In some other cases, one or more species of Characeae are structurally intrinsic to the vegetation of Potametea: on…
The role of herbaria for taxonomic and distributional studies in Characeae: examples from the Herbarium Mediterraneum Panormitanum (PAL) and the Flor…
2018
Characeae is a taxonomically critical family. Taxonomical uncertainties inevitably affect its distributional data. The role of herbarium specimens, particularly types and original material, is crucial for unravelling taxonomical ‘knots’. Moreover, wet areas have undergone dramatic reduction and modification in the last century and historical herbarium specimens may represent basic documents for the reconstruction of former distributions. Some preliminary data from two different Italian Herbaria are here presented. The Herbarium Mediterraneum Panormitanum (PAL, the standard acronym according to the Index herbariorum, http://sweetgum.nybg.org/ ih) houses four folders of Characeae exsiccata. T…
New findings for the charophyte flora of Sicily (Italy)
2022
Food Sources for Benthic Grazers in Trophic Networks of Macrophyte Habitats in a Transitional Baltic Ecosystem
2022
In this study, we provide insights into that characteristics of two sites representing different conditions of productivity and salinity impact on trophic network structures of macrophyte habitats and diet of benthic grazers at the active vegetation period in the Curonian Lagoon (southeastern Baltic Sea). Regarding the epiphytic growth, macrophytes were more overgrown in the relatively less productive (northern) site with a muddy bottom and more frequent marine water inflow than in the (southern) site with higher productivity and freshwater sandy habitat. Stable isotope analysis revealed that organisms’ samples from the northern site were more enriched with the heavier carbon isotopes, but …