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Abstract: Constructed wetlands and algae-based systems have been compared regarding their efficiencies on faecal bacteria removal. Two types of constructed wetlands, sub-surface (SSF) and free water surface (FWS) flow systems, and two more types of algae-based systems, high rate algae ponds (HRAP) and maturation pond (MP) have been studied for two years. All systems treated the same wastewater from a rural locality in León (northwest of Spain). Hydraulic retention time was 3 days for both wetland systems, 20 days for the maturation pond and 10 days for the high rate algae pond. Total coliforms, faecal coliforms, faecal Streptococci, Clostridium perfringens, and Staphylococci were analyzed in the influent and effluents of each system. A comparison among the wetland systems showed that SSF were more efficient than FWS system when considering surface removal rates (cfu removed/m2/d). Nevertheless, differences were not statistically significant. Considering mean removal efficiencies (in log unit), results showed that higher reductions were observed in FWS for most of the groups except for clostridia and Staphylococci. Concerning algae-based systems, MP showed higher removal efficiencies than HRAP, getting higher surface removal rates in the HRAP. Generally constructed wetlands were more efficient than algae-based systems when considering both, efficiencies in % and surface removal rates. [Copyright &y& Elsevier]

Light has been identified as one of the main factors affecting seaweed ecophysiology. We investigated the dependence of nutrient metabolism on sun and shade light conditions and whether episodes of upwelling of nutrient-rich subsuperficial water could reduce the summer nutrient limitation driving physiological changes in Palmaria palmata (L.) Kuntze. We measured the major nutrient pools, photosynthetic pigments, and light curves, under sun and shade conditions during a summer period when one upwelling was recorded. The redundancy analysis (RDA) produced two clear groups: sun- and shade-acclimated algae. Light was the major predictive factor. Sun-acclimated algae exhibited higher carbon (C) and lower nitrogen (N) and phosphorus (P) content in association with the storage of floridoside (main C reserve) to benefit from higher irradiance (under nutrient limitation). Among N pools, N reserves (phycoerythrin, nitrate) were a lower proportion of the total N in sun-acclimated algae, suggesting their degradation to fulfill the N demands of the cell. The orthophosphate content was also lower in sun-acclimated algae, indicating its utilization as a nutrient reserve. In contrast, N within cell walls and membranes and chl a contributed to a similar proportion of the total N in sun- and shade-acclimated algae, suggesting a response to sustain cell integrity. Transient high nutrient concentration due to the upwelling was unrelated to the nutrient content of the thallus. The storage of C as floridoside from high light exposure was shown to be the driving force for the metabolic adjustment of P. palmata at the end of summer before the onset of dormancy. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the short-term effects of wildfire on fungal communities in two Mediterranean ecosystems in northwestern Spain, dominated by Pinus pinaster Ait. and Cistus ladanifer L., respectively. A large wildfire burned the areas on August 2002. During the autumn of 2003, fruiting bodies found in the plots were identified, and mycological richness, diversity and production in both burned and unburned areas were measured. A 50m×2m transect was established in each plot. In P. pinaster plots, total fungal dry weight decreased from 35.3kgha−1 in unburned plots to 1.9kgha−1 in burned plots, where richness, diversity of mycorrhizal species and production of edible fungi were significantly lower. Dry weight for mycorrhizal species was higher than for saprophytic fungi in the unburned treatments (75% and 25% of the total, respectively), but it was not significantly different in burned areas (56% and 44%). In C. ladanifer plots, mycorrhizal species diversity was higher than that for saprophytic species. However, diversity of total, mycorrhizal and saprophytic fungal species was significantly lower in burned plots. An overall decrease of richness was also observed in these plots. Fire significantly increased the abundance of the pyrophytic mycorrhizal species Leccinum corsicum, whereas Boletus edulis, usually associated with C. ladanifer in northwestern Spain, was not found in burned plots. Some mycorrhizal fungi associated with C. ladanifer are common to Pinus forests, so these pyrophytic shrubs can play an important role in the regeneration of P. pinaster stands after wildfire. [Copyright &y& Elsevier]

The thalli of Halimeda tuna (Ellis & Solander) grow horizontally from rocky surfaces and present an upper and lower surface which can be colonized by epiphytes. Thalli of H. tuna were collected twice a month from March 1985 to March 1986 at Tossa de Mar (northeast Spain). Thirty five species of hydroid were recorded living on H. tuna thalli; of these, the 15 most abundant species were classified into three groups on the basis of their horizontal zonation on the thalli: those most abundant on the proximal, medial or distal articles. Those hydroids common on the proximal (oldest) articles were relatively large and were present throughout the year, those common on the medial articles were smaller and often occurred in dense monospecific patches, while those common on the distal (youngest) articles were present for only short periods and were the most opportunistic hydroids found on H. tuna. We hypothesize that this zonation reflects interspecific niche-selection, enabling successful competition for space with other hydroids, algae and bryozonas. Three hydroid species were more abundant on the upper surfaces of the algae than on the lower, probably because of gravitationally enhanced settlement of planula larvae coupled with (unusually) limited hydrorhizal growth on the underside. Three opportunistic species were more common on the lower surfaces of the thalli, possibly reflecting the greater availability of substratum in the shade, where epiphytic algae were less abundant. Many hydroids declined in abundance in summer because of the death of old thalli, the growth of new thalli and of apical articles on existing thalli, and possibly because of interspecific competition with epiphytic algae. The death of old thalli and the growth of new thalli reduced the abundance of epiphytic algae; this may have facilitated the increase in abundance of hydroids recorded in the autumn. [ABSTRACT FROM AUTHOR]

Characterizes the lichen Leptogium subaridum based on material from various localities. Differentiation of two morphological forms; Description of L. magnussonii and L. subaridum; Morphology and anatomy; Comparison of Spanish specimens with those from North America.

Leptogium quercicola (Collemataceae), a new corticolous species, is described from central and south-eastern Spain. It is closely related to L. lichenoides, but differs in the development of dense fruticolous cushions, with lobes narrower than the smallest known forms of L. lichenoides. Moreover, spore length and width of the two taxa are significantly different. In addition, the two species differ ecologically; L. quercicola growing directly on bark of Quercus spp., while L. lichenoides colonizes rocks, soil and bark but always among mosses. [ABSTRACT FROM AUTHOR]