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Research has long focused on the relative importance of leaves and roots as sources of nutrient supply for macrophytes, as well as the function each stream compartment plays in their growth and development. This study aims to expand the debate on aquatic ecology and to better understand the connection between compartments in aquatic systems by highlighting the relationship observed in rivers between nutrients in macrophytes tissues, water, and sediments. We measured the concentrations of P-PO4, N-NO3 and N-NH4 in three different compartments of the Amengous stream in the Middle Atlas of Morocco. Myriophyllum spicatum (L.), Groenlandia densa (L.) Fourr. and Zannichellia palustris (L.) were selected as plant species. Our results show that even if the species coexist in the same habitat, they respond differently to nutrient richness. G. densa has a higher nutrient accumulation capacity than M. spicatum and Z. palustris and prefers the water compartment as a nutrient source. Although M. spicatum can accumulate phosphate compounds from water and sediment, ammonium is not its preferred nitrogen source. Z. palustris shows a tendency to accumulate nitrogen compounds through the roots, while it prefers the assimilation of phosphorus compounds through the leaves rather than the roots. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are among the most susceptible to biological invasions. The South American Ludwigia hexapetala is an aquatic plant that is becoming an increasing threat in many European waterbodies, recently including Italy. This study aimed to define the main parameters influencing the early colonization stage of L. hexapetala by overlapping the percentage cover of this species with environmental parameter data collected at 24 aquatic sites from six waterbodies in north-central Italy. At each site, chemical and physical characteristics of the water (temperature, pH, dissolved oxygen, conductivity, nitrates, phosphates, ammonia, depth, transparency), grain size of the substrate and level of anthropogenic disturbance were evaluated. The results showed that although L. hexapetala prefers shallow, warm, alkaline, moderately rich in ions and nutrients (especially phosphates) and oxygen-poor waters, it can grow in a wide range of environmental conditions. Moreover, as a typical invasive alien species, it spreads opportunistically in disturbed, unstable sites. Thus, L. hexapetala can invade freshwater habitats with different environmental conditions and subjected to anthropogenic disturbance. However, the results suggest that water depth may be a limiting factor in the early colonization stage of this species, which does not seem to be able to colonise waters deeper than 1 m in investigated sites, while it has been observed in significantly deeper waters in other European countries with a longer invasion history. Detecting the environmental parameters that most influence the growth of L. hexapetala becomes crucial both to identify the sites most at-risk of invasion in which to initiate timely monitoring actions for the species, and to be able to develop better management and control actions for this alien species in sites that have already been invaded. [ABSTRACT FROM AUTHOR]

The Azores laurel Laurus azorica (Seub.) Franco is a highly esteemed forest species in Morocco due to its medicinal and aromatic properties. However, the natural habitats of this species are increasingly scarce, resulting in its classification as a rare species. This study comprehensively investigates the autoecology, plant communities, and distribution patterns of L. azorica, aiming to discern the crucial ecological factors underpinning its survival and shed light on its conservation status. Field surveys, including floristic relevés and environmental characterization, were conducted to identify the primary plant communities hosting remnants of L. azorica. Fieldwork and ecological analysis reveal five distinct plant communities associated with L. azorica: low elevation thermophilic holm oak woodland, mesophilic mid-altitude holm oak woodland, Quercus faginea, deciduous broadleaf mountain and Cytisus balansae plant communities. The study emphasizes the importance of ecological requirements such as oceanic exposure, rainfall, temperature, and forest mull soils in creating suitable habitats for L. azorica populations. Currently, L. azorica populations in Morocco are represented by small trees, shrubs, or bushes, often exhibiting distorted and damaged structures due to unregulated pruning. Natural regeneration of the species is completely absent. The value chain associated with L. azorica is limited, involving informal harvesters, intermediary herbalist grocers, and final consumers, due to the lack of a legal framework for resource evaluation caused by its severe depletion. To secure the survival of L. azorica in Morocco, it is crucial to address gaps in legislation, intensify conservation efforts, and promote sustainable development practices. Protecting and restoring the natural habitats of the species, along with implementing responsible harvesting practices, are essential steps towards conserving this valuable forest species.

Two of the most fundamental questions in tadpole biology, also applicable to most small, under‐studied organisms are: (1) 'Why are they built the way they are?' and (2) 'Why do they live where they do?' Regrettably, despite significant progress in most aspects of tadpole biology, the answers to these questions are not much better now than they were in the last century. We propose that an autecological approach, that is the careful observation of individuals and how they interact with the environment, is a potential path towards a fuller understanding of tadpole ecomorphology and evolution. We also discuss why more attention should be given to studying atypical tadpoles from atypical environments, such as torrential streams, water‐filled cavities of terrestrial plants and wet rock surfaces neighbouring streams. Granted, tadpoles are rare in these settings, but in those unusual habitats the physical environments can be well described and characterized. In contrast, the more common ponds where tadpoles are found are typically too structurally complex to be easily delineated. This makes it difficult to know exactly what individual tadpoles are doing and what environmental parameters they are responding to. Our overall thesis is that to understand tadpoles we must see exactly what they are doing, where they are doing it, and how they are doing it. This takes work, but we suggest it is feasible and could greatly advance our understanding of how anuran larvae have evolved. The same strategies for studying tadpoles that we encourage here can be applied to the study of many other small and fast‐moving animals. [ABSTRACT FROM AUTHOR]

The paper deals with the information obtained from the biogeographical analyzes conducted in the specially protected Ilisu State Nature Reserve in the northwestern region of the Republic of Azerbaijan. Based on the biogeographic composition of the research area, the bioecological characteristics of certain species of flora, fauna, and fungi are studied as an example. The problem the continuous study the biodiversity of these specially protected areas. It is important to collect scientific information related to this topical issue and publish it in the form of articles in both local and international journals. We studied some of the fauna, flora, and fungi that spread in this area, and bioecologically analyzed some of their representatives (Dendrocopos major, Coccinella septempunctata L., Chelidonium majus L., Rosa arvensis Huds, Polyphylla fullo, Mantis religiosa, lecanora garovaglioi, Xanthoria parietina, Phyllactinia guttata wallr.). All systematic, phytogeographical, zoogeographical analyzes are given in thepaper. [ABSTRACT FROM AUTHOR]

Changes in water qualities of the natural aquatic bodies cause habitat and species diversity lost. To understand effects of seasonal water quality changes on the ostracod species diversity and occurrences in Lake Eğirdir (Isparta, Turkey), a total of 23 ostracod taxa (10 live species, 13 taxa) were collected from ten stations in the lake during three years of seasonal samplings from 2016 to 2018. Six taxa (Candona candida, C. cf. weltneri, Fabaeformiscandona breuili, Heterocypris incongruens, Ilyocypris decipiens, Limnocythere inopinata) are new reports for the lake. There was no significant difference between the numbers of species found from littoral and pelagic zones. The number of ostracods were higher (4 live, 14 taxa) in winter seasons than the spring (5 live, 10 taxa), summer (4 live, 9 taxa) and fall (8 live, 5 taxa) seasons. Ostracod Watch Model illustrated that Physocypria kraepelini, Neglecandona neglecta and Darwinula stevensoni showed similar seasonal occurrences in almost all seasons during the study. Of these, P. kraepelini was the most abundant species while the others were relatively rare and/or very scarce in their occurrence and abundance values. The mean value of the dissolved oxygen was significantly different between pelagic and littoral zones (p < 0.05). The CCA diagram displayed 84.4% of the correlation between eight species and five ecological variables (water temperature, ammonium, pH, dissolved oxygen, depth). Two species (P. kraepelini and F. breuili) and D. stevensoni showed significantly negative correlation with NH4 and pH, respectively. Species with similar optimum values seemed to have similar ecological and/or habitat preferences along with similar seasonal occurrence patterns. Results point to a reverse relationship between ecological tolerance and optimum estimates of the species. Thus, ostracods with a narrow tolerance range can be considered good indicator species for the water quality estimates. Accordingly, our measurements exhibited that Lake Eğirdir is mainly dominated by NO3-N and NH4-N, suggesting a critical reduction in water quality values. Compared with the fossil ostracods, finding six live of 12 fossil species during the present study provides supportive evidence that aquatic conditions of the lake have been declining since the Holocene age. Indeed, dominance of cosmoecious species and absence of several rare species can also be other supportive evidence of the lake water quality decline. [ABSTRACT FROM AUTHOR]

Twenty-four individuals of Albunea carabus (Linnaeus, 1758), a species rarely reported in the Mediterranean Sea, have recently been collected in the Tyrrhenian Sea (Italy) in hydraulic dredge surveys carried out to assess local razor clam stocks. They were found in sandy bottoms at depths of 1–6 m in association with the commercial bivalves Ensis minor and Chamelea gallina and the decapods Diogenes pugilator, Portumnus latipes and Liocarcinus vernalis. The distribution of the species in the Italian seas is described based on a careful search of the available records. Notes on its reproductive biology and autoecology are also included.

Twenty-four individuals of Albunea carabus (Linnaeus, 1758), a species rarely reported in the Mediterranean Sea, have recently been collected in the Tyrrhenian Sea (Italy) in hydraulic dredge surveys carried out to assess local razor clam stocks. They were found in sandy bottoms at depths of 1–6 m in association with the commercial bivalves Ensis minor and Chamelea gallina and the decapods Diogenes pugilator, Portumnus latipes and Liocarcinus vernalis. The distribution of the species in the Italian seas is described based on a careful search of the available records. Notes on its reproductive biology and autoecology are also included. [ABSTRACT FROM AUTHOR]

The family Carabidae is of particular interest not only due to its great specific diversity but also due to the geophilic nature of many of its members, which makes them good bioindicators of soil characteristics. The diversity of the epigean Carabidae is relatively well studied. However, there are no robust data on the presence of these beetles in hypogean habitats of non–karstic substrate and, therefore, without the development of caves. In the present study, we sampled the mesovoid shallow substratum (MSS) at various sites in the Sierra de Guadarrama National Park, with the aim of characterising the Carabidae hypogean fauna. Among many other organisms, we collected 12 species of Carabidae. Of these, despite being known from epigean/edaphic habitats, Leistus (Leistus) constrictus Schaufuss, 1862, Nebria (Nebria) vuillefroyi Chaudoir, 1866, Trechus (Trechus) schaufussi pandellei Putzeys, 1870, and Laemostenus (Eucryptotrichus) pinicola (Graells, 1851) are consistently reported from MSS habitats, albeit with certain differences as regards their occupation of subterranean spaces. The species from forest–dwelling (thermophilous) lineages, T. (T.) schaufussi pandellei and L. (E.) pinicola, presented a higher prevalence in subsoil cavities at lower altitudes, whereas those from orobiont (psychrophilic) lineages, L. (L.) constrictus and N. (N.) vuillefroyi, predominated in subsoils at higher altitudes. As regards the presence of these four species during their different life cycle stages, we found that N. (N.) vuillefroyi was present and abundant as both larval (in the three preimaginal stages) and imago stages, showing the most evident trend towards an hypogean lifestyle. In contrast, for the other three species, only one of the two stages showed a high presence on hypogean habitats. The facultative hypogean capabilities of N. (N.) vuillefroyi and L. (L.) constrictus calls into question the protected status conferred on both species when it was thought that they were exclusively epigean.

Abstract. Aim. The aim is to study the threshold sensitivity to salinization of the environment of individual isolated structures for evaluating the salt tolerance of plants. Methods. Comparison of the reaction to salinization of seeds, sprouts, epicotyls, leaves, cotyledons and flowers in species of cultural and natural flora. The following parameters were taken into account in the work: the life span, the time and capacity of for mation of roots and buds, and the wet and dry biomass of species. The results were processed by Statara version 3.0 Shareware (Statistic 5.0) by the parameters of the interaction of roots and shoots. Results. Plant individuals are characterized by the presence of structures that differ in specialization and life span. The question of the correspondence of reactions of structures with the salt tolerance of plants needs to be studied. The stability of the individual as an integral system is determined by the interaction of organs and structures with each other and with other components of the complex community. It evolves in the course of evolution by selecting individuals in the formation of stable plant communities. Quantitative methods of autoecology and genetics of populations are used to understand its mechanisms and role. Conclusion. The structure of an individual plant in an isolated culture is characterized by the specific reaction to salinization of the environment. In this case, the reaction of seeds, sprouts and isolated epicotyls corresponds most closely to the stability of the individual under the stress.

The objective of this study was to assess the patterns of seed dispersal syndromes of woody plants from nine forest fragments distributed at different altitude levels on the Araripe plateau, in Pernambuco, Brazil. For data collection, we divided the altitudes within the region into three categories: lower level (altitudes =600 m); intermediate level (600< altitudes <750 m); and higher level (altitudes =750 m). We registered nine fragments, three per altitude level. In each of them, we distributed 20 rectangular sampling units with 250 m², totaling a sampling area of 4.5 ha. We quantified, collected, and identified woody plants with a diameter at breast height higher than or equal to 0.1 m (DBH 1.30 m =0.10 m). We characterized the dispersal syndrome according to the characteristics of the fruits and seeds and based on a literature review. In the whole region, we sampled 6,987 individuals, distributed in 35 families, 82 genera, and 153 species. Approximately 41% of all individuals are dispersed by animals, 37% by the plant's own mechanisms, and 21% by the wind. In terms of dispersal, 47% of species were classified as zoochorous, 23% as autochorous, and 14% as anemochorous. Seed dispersal patterns vary according to altitude levels, with higher regions tending to present greater representativeness of biotic dispersers and lower ones, abiotic. [ABSTRACT FROM AUTHOR]

The calculation of autoecological data, such as optima and tolerance ranges to environmental variables, can be useful to establish the distribution and abundance of the species. These calculations, although mathematically not complex, can be prone to error when using a large database. We show how to calculate the optimum value and tolerance ranges of multiple species to multiple environmental factors in a single run, by weighted average using a specific R package ('optimos.prime'). Using sample data from a phytoplankton database, we exemplify the use of the R package and its functions. A stand‐alone version for Windows is also provided, and source code and documents are freely available on GitHub to encourage collaborative work. [ABSTRACT FROM AUTHOR]

Utricularia australis is an aquatic rootless carnivorous plant that takes up nutrients through shoots or from trapped prey digested in its bladders. As the information on the ecology of this species is scarce, the main environmental factors which favour or limit its growth were analysed. Habitat characterization was carried out on 23 aquatic sites in Central Italy where U. australis occurred. Diverse water chemical and physical factors and aquatic plant dominants were sampled and compared to Utricularia coverage. Species response curves with respect to each analysed ecological factor were elaborated. Despite the large environmental variation among sites, U. australis did show some ecological preferences. Optimal growth of Utricularia was associated with sunny sites (~ 1500 µmol photon m−2 s−1) and shallow waters (< 20 cm) that were warm (~ 26 °C), alkaline (pH 8.3 median value), with moderate-high conductivity (700 µS cm−1) and with low aquatic inorganic phosphorus (< 10 µg L−1) but higher nitrogen (800–1600 µg L−1). Dissolved and particulate organic nutrients (mainly phosphorus) were highly important in determining U. australis ecology and its distribution. The knowing of the ecological preferences of U. australis, a plant that is becoming increasingly rare in Central Italy, could be very useful to identify and protect its habitats or to identify new potential sites and to avoid further population losses. [ABSTRACT FROM AUTHOR]

Corticosterone (CORT) is the main glucocorticoid hormone of amphibians, reptiles, birds and some mammals. This hormone may have evolved as an adaptive metabolic mechanism, in part because increased concentrations of CORT are essential for individuals to manage energy resources and thus cope with negative perturbations such as predation and storms. The benefits of CORT are offset by costs, because elevated levels can suppress inflammatory responses of individuals, making them more susceptible to parasites and pathogens. In this study, we investigated the relationships between feather CORT levels, infection status and diversity of haemosporidian parasites in the Blue‐crowned Manakin Lepidothrix coronata, considering possible effects related to the sex and age of individuals. We predicted higher levels of feather CORT in infected individuals. We observed that feather CORT levels were similar among individuals of different sexes and ages. Although haemosporidian infection status did not vary among sexes, occurrence probability was higher among younger individuals, which may indicate that the less developed immune system of these individuals makes them more susceptible to avian malaria. Contrary to expectations, we found that feather CORT levels were not associated with the infection status and diversity of haemosporidian parasites. That haemosporidian occurrence probability does not increase with elevated feather CORT levels suggests that individuals are not immunosuppressed by elevated levels of this hormone, at least to the extent that feather CORT truly reflects individual differences in the level of this hormone. [ABSTRACT FROM AUTHOR]

• Autoecological traits of aquatic life provide crucial information on hydrosystems. • The diatom autoecological matrix used in France is not suited to French environment. • We elaborated a new French-specific diatom autoecological trait matrix. • This work provides new fundamental knowledge on French taxa. • This new matrix will be used by French water managers for ecological diagnosis. Autoecological traits of aquatic organisms are well known to provide crucial information on hydrosystems and are good complements to biotic indices for evaluating surface water ecological quality. In France, as in many other European countries, autoecological approaches concerning diatoms are based on a checklist developed in the Netherlands. While this work was pioneering and suited to the conditions of study, ecological indicators developed in such small scales and such specific natural environments often show reduced efficiency when used in other conditions. France is a vast and highly biogeographically diversified region with many situations that are not to be found in the Netherlands, such as limestone substrate rivers and torrents in mountainous areas. Consequently, the elaboration of a better suited autoecological reference system has been long requested by French water managers to support ecological diagnosis. In this study, we elaborated a new autoecological reference system gathering knowledge on environmental optima, tolerance and range values for 809 French diatom taxa, along with an ordinal classification for 7 autoecological traits: water acidity, water mineralisation, oxygen requirements, saprobity, trophic state, organic nitrogen and nitrates. By combining weighted averaging and regression tree techniques we also produced a simple, statistically robust and reproducible approach to study univariate taxa-environment relationships in a given region. This new trait matrix, in addition to providing autoecological attributes for over 200 French diatom taxa that had no correspondence in previous reference systems, also takes into account French specificities such as the scarcity of acidic situations and mineral nitrogen issues. On the basis of this new matrix, 3 autoecological functional groups have been identified in French diatom flora, mainly related to traits linked to anthropogenic disturbance. This revised autoecological classification will provide much more reliable information on French stream benthic diatoms ecology, and should therefore allow better ecological diagnosis if accompanied by rigorous management of synonyms and taxonomic levels. [ABSTRACT FROM AUTHOR]

The American duckweed Lemna minuta shows an invasive behaviour in Europe, causing weed problems in aquatic habitats there. Few studies addressed this species' ecological requirements for a suitable establishment in a site. In this paper, L. minuta populations were analysed through field surveys so as (1) to define the autoecology of this duckweed as regards the main environmental factors characterizing invaded habitats, and (2) to identify possible overlaps/differences in ecological requirements between the alien L. minuta and the common native L. minor, with which it is often associated and in direct competition. The occurrence/abundance of the two species and environmental data were collected from 41 wetlands in central Italy. Currently, L. minuta is more common and abundant than L. minor in the study-area, despite its recent arrival there (2007). The two species have a partially overlapped autoecology. However, L. minuta differs from L. minor since it occurs in waters which are less alkaline, slightly less warm, and richer in nitrates. It shows tolerance for environmental conditions which are limiting for most of macrophytes, including L. minor, such as high shading and low water oxygenation. This enables L. minuta to increase its invasion potentiality and thus to enlarge its distribution area. [ABSTRACT FROM AUTHOR]

Reproduction, diet and sexual dimorphism are three crucial descriptive natural history parameters necessary to understand and recognize evolutionary processes and patterns across different taxa. The recognition of distinct patterns and how traits vary in related species/population give us a better understanding of the role environment characteristics play in the evolution and maintenance of such traits.Gymnodactylus(Phyllodactylidae) currently comprises five species widely distributed in both forested and open formations in Brazil.Gymnodactylus geckoidesis mainly associated with the Caatinga domain, but also reported for the first time in a Restinga site in this study. Herein, we analysed the species’ reproduction, diet and sexual dimorphism, based on 181 specimens collected over a period of 16 months from a Restinga site in north-eastern Brazil. Reproduction was continuous and females only lay one egg per clutch, while most juvenile recruitment occurs from June through October.Gymnodactylus geckoidesis a generalist feeder (Isoptera and Orthoptera the predominant prey items in its diet) and sit-and-wait forager based on dietary items and habitat use. Females are significantly larger than males and sexes can also be distinguished based on shape variables: males have higher heads and longer hindlimbs than females. We comment on the intra- and interspecific variation on these traits in comparison to related species from other biomes. Although pointed out as an important feature shaping reproductive strategies in Neotropical lizards, environment seasonality did not influence reproduction and phylogenetic inertia is proposed as one possible force explaining clutch size patterns found. [ABSTRACT FROM AUTHOR]

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Moringa peregrina is a tree or shrub componend sub-tropical vegetation and extending from Dead sea and is scattered in Red sea and spread throughout northern Somalia and around the Arabian Peninsula to mouth of the Persian Gulf, Oman, UAE, Iran, Pakistan. In Iran it is limited to Hormozgan and Sistan&Balochestan provinces within Bashagard area to Pakistan and Iran boundary 100 to 1500 m. above sea level on mountain and foothills regions. The habitate of Moringa peregrina is locatated in Sahara- Sindian climatic region with hot summer, moderate winter and no frozen period, Mean annual rainfall 180-200 mm, Mean annual temperature 27ºC, Mean annual evapo-transpiration 3448 mm. Moringa often occupy Makran geological ranges, tertiary geology structural unit and Angohran, Roksha, Dar pahn and Guredak complexes. Stands parent material conclude sandstone, shale and mudstone. some time conglomera, limstome, volcanic and metamorphic stones present in bed rock. The results of soil analysis showed the soil texture in most stands is sandy- loam but in some stands are sandy-clay-loam, acidity is 7.98 and electric conductivity 1.78 des/m and no salt. M. peregrina is a evergreen plant and its growth therm is started in autumn when proper temperature and enough rainfall are occured، leaf buds begin to sprout and primary leave appear. These leaves are short-lived and start to fall in May when temperature go warm. White and pink flowers appear in February and March. Pod-like and green fruit appear on young branches in April and May. Fruit ripening start simultaneously maturity dates in July and seed are starting to drop in August. Rainfall during the Flowering time is induced the flowers are not inoculated and other phonological phases are affected. Dependence between Moringa and geological formation caused habitates are discontinuous mode. Individual distribution pattern in stands level is random pattern. Mean of density was about 29 trees in hectar, d.bs. 29.6 centimeter, height was 3.16 meter and canopy cover 3.5% which are different in stands. Most trees are middle-aged to older and due to aging and environmental stresses as well as frosting periodic , most of Moringa is reformed to shrub and coppice type

Morphological stomatal traits, such as size, form and frequency, have been subject of much literature, including their relationships with environmental factors. However, little effort have focused on ferns, and very few in the genus Blechnum. Stomatal length, width and frequency (as stomatal index) of a number of specimens of fourteen Neotropical species of Blechnum were measured in adult pinnae. The aim of the work was to find biometrical relationships between stomatal traits and between stomatal traits and habit, habitat and ecosystem of the plants. Statistical analyses of data were conducted using Exploratory Data Analysis and Multivariate Statistical Methods. Stomatal length and width showed a very high correlation, suggesting an endogenous, genetic control, thus giving these traits a considerable diagnostic utility. With respect to the relationships between stomatal traits and environment, we found significant statistical relationships between altitude and stomatal index. We also addressed the interpretation of the ecological- selective significance of various assemblages of stomatal traits in a diverse conjunction of habits, habitats and ecosystems. Rev. Biol. Trop. 59 (1): 403-415. Epub 2011 March 01.Los caracteres morfológicos estomáticos, tales como tamaño, forma y frecuencia, han sido objeto de abundante investigación, incluyendo su relación con los factores ambientales. Sin embargo, poco esfuerzo se ha realizado en esta materia en helechos y menos todavía en el género Blechnum. En este trabajo se midieron la longitud, anchura y frecuencia (como índice estomático) de estomas de pinnas adultas de un número de individuos en catorce especies de Blechnum neotropicales. El objetivo fue encontrar relaciones biométricas entre los caracteres estomáticos, y entre los caracteres estomáticos y el hábito, hábitat y ecosistema de las plantas. Se realizaron análisis estadísticos como Análisis Exploratorios de Datos y Métodos Estadísticos Multivariantes. La longitud y la anchura de los estomas mostraron una muy fuerte correlación, sugiriendo un control genético endógeno que otorga a estos caracteres un considerable valor diagnóstico. Con respecto a las relaciones entre los caracteres estomáticos y el ambiente, encontramos una relación estadísticamente significativa entre la altitud y el índice estomático. También se incluyen interpretaciones de la significación ecológico- selectiva de un conjunto de caracteres estomáticos en diferentes conjuntos de hábitos, hábitats y ecosistemas.

The purpose of the present work is to characterize the functioning of the ecosystems of semideciduous and deciduous Atlantic oaks in the northwest of the Iberian Peninsula. The studied species were: Quercus robur L. and Quercus petraea (Mattuschka) Liebl. To advance in the knowledge of the autecology of these species it is necessary to descend at the regional level and describe in detail the variability of the environment to determine their potential, and to decide the silvicultural treatments to be applied to preserve them and to analyze future actuations in order to a possible expansion. The analysis of the results allows knowing differences in continentalityand site conditions, with more precipitation, soil variability and humidification in Q. petraea forests respect to Q. robur. These information represent appropriate measures for the sustainable and multifunctional management of these forests, useful as indicators environmental and forestry parameters as well as the conservationstatus of these formations.

Potentially toxic species of the genus Pseudo-nitzschia were studied along the Spanish NW Mediterranean coast from January 2005 to May 2006. Observation in electron microscopy revealed the presence of Pseudo-nitzschia brasiliana, P. calliantha, P. delicatissima, P. fraudulenta, P. multistriata and P. pungens. Several strains were isolated from coastal waters and their clonal cultures were compared by combined techniques, including light and electron microscopy and internal transcribed spacer (ITS-1, 5.8S and ITS-2) rDNA sequencing. Cultured isolates were submitted to HPLC analysis of pigments to evaluate the possibility of taxonomic discriminations by means of a simple chemotaxonomic approach. The genus Pseudo-nitzschia showed high cell concentrations during most of the year, but the population initiated a sharp decline at all stations in the period between April and May. P. delicatissima with P. calliantha were found at the northern stations between February and April, and at the southern stations between August and November. P. brasiliana and P. multistriata were only occasionally detected in the southern region. None of the environmental variables considered was significant to explain the observed spatial and temporal distributions of Pseudo-nitzschia species in the area studied. Differences in the growth rate and cell yield of the species indicate that biotic factors may play a role in the observed distributional patterns.

Se estudió el efecto de la elevación sobre algunos aspectos autoecológicos de la especie Espeletia pycnophylla ssp. angelensis Cuatrec. (Asteraceae), tales como su estructura demográfica, densidad poblacional, patrón de distribución espacial, producción de estructuras reproductivas, morfometría de adultos y supervivencia, en un páramo seco del departamento de Nariño (Colombia). Las hipótesis propuestas por otros autores acerca del efecto lineal que la elevación produce sobre estas variables, fueron completamente rechazadas. La elevación induce un efecto coenoclínico sobre la densidad poblacional y ésta a su vez, se correlaciona negativamente con la producción de estructuras reproductivas y el tamaño de los adultos, evidenciándose un efecto inequívoco del fenómeno de la densodependencia sobre el potencial biótico de la población. En la zona intermedia del gradiente, la densidad poblacional es máxima, pero los tamaños corporales son reducidos, la producción de estructuras reproductivas es mínima y la probabilidad de que un juvenil alcance edades avanzadas es baja. Evidentemente, esta elevación intermedia estaría presentando condiciones ecológicas favorables para el establecimiento y supervivencia de plántulas, lo que a largo plazo conlleva a un aumento de la densidad poblacional. Se propone que las generalizaciones de otros autores acerca de la influencia de la elevación sobre la autoecología de estas plantas son inverosímiles y limitadas, ya que la historia particular de vida y disturbio del páramo y los aislamientos espaciales, ecológicos y genéticos, son factores explicativos que no pueden aislarse del contexto. Paralelamente, la población se ajustó al modelo demográfico logarítmico, revelando su temprano estado de regeneración frente a la última quema ocurrida en el 2003, y la similitud de las curvas de supervivencia entre todas las elevaciones, probó una alta estabilidad demográfica.Some autoecological features of Espeletia pycnophylla ssp. angelensis Cuatrec. such as its demographic structure, population density, spatial pattern of dispersion, production of reproductive structures, adult morphometry and survivorship, were studied in an altitudinal gradient on a dry paramo of Nariño (Colombia). Hypothesis proposed by other authors about a linear effect caused by the elevation on these variables were completely rejected. The elevation induces an ecoclinal effect on population density, and this density correlates negatively with both production of reproductive structures and adult sizes. These results elucidate an unequivocal effect of density-dependence phenomena on population fitness. The intermediate zone of the altitudinal gradient exhibits a high population density, but on the other hand show reduced corporal adult sizes, minimal production of reproductive structures and the probability of juveniles reaching advanced ages is low. Evidently, this intermediate elevation can have favorable ecological conditions for the seedling establishment, wich increments population densities at long term. We propose that other author's generalizations about the influence of elevation on the autoecology of these plants are limited, because the particular life and disturbance stories of paramos and the spatial, ecological and genetic isolating are explicative factors impossible to take away from the context. The demographic structure of the population fitted the logarithmic model, revealing its early regeneration state from the last fire event on 2003 and the similarity of the survivorship curves among every elevation, probed a high demographic stability.

Holocene record of ostracode shell chemistry from the South Basin of Lake Manitoba shows how isostatically and climatically induced changes in the surface and groundwater input to the overall hydrologic budget affected the hydrochemistry. The shallow South Basin experienced periods of extensive shell transport from isolated pools and groundwater seeps, as suggested by disparate chemistry of Fabaerformiscandona rawsoni shells from the same 1-cm-thick sediment sample. Temporal changes reconstructed from ostracode species and F. rawsoni shell chemistry include, for some depth intervals, shells of individuals that were not living at the same time or were not living at the core site. Shell chemistry before the South and North Basins became connected at 1850 BP broadly show a hydrologically closed-basin behavior with alternating periods of a more and less stressful environment to ostracodes. F. rawsoni with high δ O and low Mg/Ca or low δ O and high Mg/Ca were likely transported from marginal evaporated pools or groundwater seeps. Overall δ O and δ C values increase over time, but at levels for which multiple analyses were made, the values show a wide range, and indicate a highly variable hydrochemical environment both spatially and temporally (over one summer or multiple summers). [ABSTRACT FROM AUTHOR]

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Key message : Biomass allocation in Castanea sativa varies according to the environmental conditions. Specifically, leaf-to-sapwood area ratio is higher on sites with good water supplies and lower in water-stressed conditions. Abstract: Ecological plasticity allows organisms to adapt and to cope with environmental conditions. This is a key trait for species with long live span, which will probably be more vulnerable to changing climate because of their lower adaptation potential via natural selection. We studied the case of the sweet chestnut tree, a naturalized forest species in many European mountain areas, where it grows on very different climates and sites. This raises the question of its adaptation capacity to very different environmental conditions. To test this hypothesis, we applied the pipe model approach for analysing the variation in the leaf-to-sapwood area ratio ( A : A ) in 82 chestnut trees growing in very different site conditions (e.g., water-stressed convex vs. water-rich concave sites). We used linear regression analyses to model the A : A relationship to environmental and dendrometric parameters. Results confirm that A : A is significantly higher when trees grow on good nutrient- and water-supplied concave sites with respect to water-stressed, convex sites. Chestnut trees are thus able to vary their biomass allocation between sapwood and leaves to adapt their hydraulic characteristics to the site conditions. Trees seem to react to water-stressed conditions by allocating more biomass in the sapwood in respect to the leaves. A : A may thus represent a useful indicator of tree species plasticity and their adaptation potential to different environmental and climate conditions. [ABSTRACT FROM AUTHOR]

Ranunculus polyrhizos is reported as a new noteworthy record for the flora of Iran. This species was collected from alpine dry gravelly slope in Talesh Mountains. Taxonomic remarks and notes geographical distribution and habitat for this species are provided. Moreover nectar scale, pollen and achene micromorphological characters of the species are added and compared with related species. [ABSTRACT FROM AUTHOR]

In the last decade, many new records for Thorea hispida (Thore) Desvaux 1898 emend. Sheath, Vis et Cole 1993 (Rhodophyta) have been collected from Europe as a probable result of the enactment of the Water Framework Directive which has fueled a renewed interest in the characterization of the macroscopic primary producers of river systems. Despite this, the species remained poorly documented, especially regarding habitat requirements and related physical and chemical drivers. To further add to the knowledge of these parameters, a three-year survey (2009-2011) was conducted along the southern reach of the Oglio River, a mid-size tributary of the Po River in Northern Italy that hosts three newly recorded populations of T. hispida. In parallel, a comprehensive review of the literature was performed. In this work, we present the first records for T. hispida from Italy, and a first detailed physical, chemical and hydromorphological characterization of its habitat. We confirm the predilection of T. hispida for turbid waters (> 80 mg L -1 of total suspended solids) with high nutrient (up to 9.4 mg L -1 for nitrates and up to 173 μg L -1 for soluble reactive phosphorous) and high conductivity levels (up to 660 µS cm -1 for conductivity). In addition, our data extended the range of tolerance of the species for temperature (5.1–26.2 °C) and pH (7.1–8.6). In general, our results and previously published data corroborate with the idea that T. hispida can not be considered a sensitive species (i.e., a taxon scarcely adapted to increasing levels of pollution), showing a preference for rivers characterized by high nutrients availability. Moreover, its rarity must be traced to the low detectability of the thallus due to species life cycle and the very limited accessibility of colonized habitats.

The diving bell spider Argyroneta aquatica is the only known spider to conduct a wholly aquatic life. For this reason, it has been the object of an array of studies concerning different aspects of its peculiar biology such as reproductive behavior and sexual dimorphism, physiology, genetic and silk. On the other hand, besides some empirical observations, the autoecology of this spider is widely understudied. We conducted an ecological study in a resurgence located in the Po Plain (Northern Italy, Province of Vercelli) hosting a relatively rich population of Argyroneta aquatica, aiming at identifying the ecological factors driving its presence at the micro-habitat level. By means of a specific sampling methodology, we acquired distributional data of the spiders in the study area and monitored physical-chemical and habitat structure parameters at each plot. We analyzed the data through Bernoulli Generalized Linear Models (GLM). Results pointed out a significant positive effect of the presence of aquatic vegetation in the plot. In addition, the presence of A. aquatica was significantly associated with areas of the resurgence characterized at the same time by high prey availability and low density of predators. Considering the ecological importance and rarity of this species, we update and revise the data on the distribution of A. aquatica in Italy. [ABSTRACT FROM AUTHOR]

Se estudió la alimentación de siete especies de cíclidos (Archocentrus octofasciatus, A. spilurus, "Cichlasoma" robertsoni , "C." synspilum, "C." urophthalmus , Petenia splendida, Thorichthys meeki) en la laguna Caobas, sur de la península de Yucatán. Los muestreos se llevaron a cabo durante las estaciones seca y lluviosa de 1995. Los ejemplares medían menos de 41 mm LP. Se evaluó la frecuencia de aparición y la abundancia de las presas. Los ítemes alimentarios predominantes fueron los quironómidos, ácaros, copépodos, cladóceros y ostrácodos. La mayoría de las mojarras se mostraron zooplanctófagas, con la excepción parcial de P. splendida (piscívora), "C." synspilum y A. spilurus (herbívoras). A. octofasciatus tuvo el más amplio espectro alimentario y se consideró omnívoro. Thorichthys meeki mostró cambios cuantitativos en la dieta por hora del día, talla del pez y estación del año, no así por sexo.Feeding habits of seven cichlid species (Archocentrus octofasciatus, A. spilurus, "Cichlasoma" robertsoni, "C." synspilum, "C." urophthalmus, Petenia splendida, Thorichthys meeki) in Lake Caobas, southern Yucatan Peninsula, were studied. Samples were taken with enclosure and cast nets during the dry and rainy seasons of 1995 (day and night). The environment was characterized by measuring temperature, conductivity and pH. All individuals were below 41 mm SL (N=281). Frequency of occurrence and prey abundance were analyzed. Main prey items were chironomids, mites, copepods, cladocerans, and ostracods. The cichlids fed mainly on zooplankton, with the partial exceptions of P. splendida (piscivore), "C." synspilum and A. spilurus (herbivores). A cluster analysis showed that the most similar trophic spectra were those of T. meeki, "C." robertsoni and "C." salvini, which were also the least diverse. "C." synspilum and A. spilurus had an intermediate distance between their diets and those of other species. The species with the most distinctive feeding composition were P. splendida (with the most diverse and equitable diet) and the omnivore A. octofasciatus (whose diet was the richest one). T. meeki showed quantitative diel, ontogenetic, and seasonal diet changes, but none between sexes. "C." robertsoni, "C." salvini and "C." synspilum differ in food habits in Caobas and in other localities, a fact that underscores the trophic adaptability of cichlids. Trophic overlap between cichlids in Caobas could imply absence of competition, perhaps because resources are abundant in the ecosystem.

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The population dynamics and gametogenesis of the non-indigenous polychaete species Branchiomma luctuosum Grube, 1869 (Annelida, Sabellidae) has been investigated at three sites in the Taranto Seas (Ionian Sea, Mediterranean Sea). The species, probably introduced from the Red Sea, has been reported in the Mediterranean Sea since 1983. The species is hermaphrodite, and the reproductive season is between June and October when the largest mean size of oocytes was recorded together with the presence of mature spermatozoa. Small oocytes are present in specimens reaching about 20-25 mm in length. Therefore oogenesis seems to begin early during the first year of life, but the first reproduction can occur when the worms attain a larger size and are at least 6 months of age. Although most of the individuals reproduce seasonally within a discrete period, some individuals can reproduce in different periods during the year, the oogenesis of individuals not being synchronous. A life span of at least 2 years is highlighted, with a faster growth rate during the first months (about 20 mm per month) decreasing to about 10 mm from the 3rd to the 8th months and slowing down again after the worm reaches 100 mm in size. Some differences in growth performance are discussed, enhanced by comparing the sites located at greater depth (5-7 m) and those located at 0.5 m depth, together with the possible interactions of this alien species with the autochthonous sabellid Sabella spallanzanii. [ABSTRACT FROM AUTHOR]

Between September 2011 and October 2012, 13 samplings at 8 stations in the Riogrande II Reservoir (Colombia) were undertaken. It is located in a high-mountainous tropical (75°32'30'' W - 75°26'10'' W and 6°33'50'' N - 6º28'07''N), which supplies water to a plant treatment for public supply and to a small hydroelectric plant. The basins of the two main tributaries of the reservoir are highly impacted by human activity. We report the presence of a Dolichospermum lemmermannii, which up to now has only been registered as a temperate and high latitude species. Also the general ecology of the species is established, such as, generation and renewal times, spatial and temporal patterns, and interaction with more important environmental variables. [ABSTRACT FROM AUTHOR]

In the last decade, many new records for Thorea hispida (Thore) Desvaux 1898 emend. Sheath, Vis et Cole 1993 (Rhodophyta) have been collected from Europe as a probable result of the enactment of the Water Framework Directive which has fueled a renewed interest in the characterization of the macroscopic primary producers of river systems. Despite this, the species remained poorly documented, especially regarding habitat requirements and related physical and chemical drivers. To further add to the knowledge of these parameters, a three-year survey (2009-2011) was conducted along the southern reach of the Oglio River, a mid-size tributary of the Po River in Northern Italy that hosts three newly recorded populations of T. hispida. In parallel, a comprehensive review of the literature was performed. In this work, we present the first records for T. hispida from Italy, and a first detailed physical, chemical and hydromorphological characterization of its habitat. We confirm the predilection of T. hispida for turbid waters (>80 mg L-1 of total suspended solids) with high nutrient (up to 9.4 mg L-1 for nitrates and up to 173 μg L-1 for soluble reactive phosphorous) and conductivity levels (up to 660 µS cm-1). In addition, our data extended the range of tolerance of the species for temperature (5.1-26.2°C) and pH (7.1-8.6). In general, our results and previously published data corroborate with the idea that T. hispida can not be considered a sensitive species (i.e., a taxon scarcely adapted to increasing levels of pollution), showing a preference for rivers characterized by high nutrients availability. Moreover, its rarity must be traced to the low detectability of the thallus due to species life cycle and the very limited accessibility of colonized habit [ABSTRACT FROM AUTHOR]

Diving or respiratory behavior in aquatic mammals can be used as an indicator of physiological activity and consequently, to infer behavioral patterns. Five Antillean manatees, Trichechus manatus manatus , were captured in Chetumal Bay and tagged with GPS tracking devices. The radios were equipped with a micropower saltwater sensor (SWS), which records the times when the tag assembly was submerged. The information was analyzed to establish individual fine-scale behaviors. For each fix, we established the following variables: distance ( D ), sampling interval ( T ), movement rate ( D / T ), number of dives ( N ), and total diving duration (TDD). We used logic criteria and simple scatterplots to distinguish between behavioral categories: ‘Travelling’ ( D / T ≥ 3 km/h), ‘Surface’ (↓TDD, ↓ N ), ‘Bottom feeding’ (↑TDD, ↑ N ) and ‘Bottom resting’ (↑TDD, ↓ N ). Habitat categories were qualitatively assigned: Lagoon, Channels, Caye shore, City shore, Channel edge, and Open areas. The instrumented individuals displayed a daily rhythm of bottom activities, with surfacing activities more frequent during the night and early in the morning. More investigation into those cycles and other individual fine-scale behaviors related to their proximity to concentrations of human activity would be informative. [ABSTRACT FROM AUTHOR]

Knowledge on ecological requirements of species is a focal point for their conservation, especially if they live in threatened habitat types such as old-growth forests., We predict that habitat requirements shape the spatial niche partition of two sibling species of saproxylic beetles Gnorimus nobilis and Gnorimus variabilis., To test our hypothesis, we conducted a comparative study on the presence and abundance of these chafer beetles in northern Apennines using air-trapping, exploring the effects of altitude and habitat type., We performed our analyses in a study area of 268 800 ha, where we detected nine patches of putatively suitable habitat (13 347 ha), setting a total of 82 air-traps., We collected an unexpected high number of specimens of both species, and found that G. nobilis and G. variabilis are rarely syntopic, having different ecological preferences influenced primarily by altitude, but also by forest type. [ABSTRACT FROM AUTHOR]

Highlights: [•] Estimation of indicator power of a species is based on qualitative criteria. [•] We introduced quantitative method of estimating indicator power. [•] The new model is able to delineate ecological conditions quantitatively. [•] The quantitative method was found to be robust in estimating indicator power. [•] Regression model is confirmatory and complimentary for estimating indicator power. [ABSTRACT FROM AUTHOR]

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Forty species of benthic hydroids, belonging to 15 families and 21 genera, were found in a collection, obtained by SCUBA diving, from the Maltese Islands. Paradoxically for the well studied Mediterranean region, the hydroid fauna of these islands is virtually unexplored. Of 40 species, 33 were identified to species level, with 28 of them reported for the first time for the study area. Hydractinia monocarpa is recorded for the first time in the Mediterranean Sea, and a presumed new species of the genus Clytia has been found. The most speciose families are Campanulariidae with 10 species (25%), Aglaopheniidae with six species (15%) and Sertulariidae with five species (12%). Aglaophenia and Clytia are the most diverse genera, both with six species (15%). A problem with respect to subspecies of Sertularella ellisi is resolved based on nematocyst observations. In terms of geographic distribution, eight species (24%) are endemic to the Mediterranean Sea, this number increases to 16 species (48%) when including those restricted to Mediterranean and nearby Atlantic waters, whereas the remaining species have wider distributions. [ABSTRACT FROM AUTHOR]

Diatom indices developed in certain geographic regions are frequently used elsewhere, despite the strong evidence that such metrics are less useful when applied in regions other than that where species-environment relationships were originally assessed, showing that species have particular autoecological requirements in different geographic areas. The goal of this study was to develop a new metric, the Duero Diatom Index (DDI), aimed at monitoring water quality in Duero basin watercourses (NW Spain). In summer 2008 and 2009, a total of 355 epilithic diatom samples were collected following standard protocols. The 2008 samples were used to develop the DDI, whereas the samples collected during 2009 were used in the index testing. Weighted averages method was used to derive the autoecological profiles of diatoms with respect to pH, conductivity, biological oxygen demand, ammonia, nitrates, and phosphates. The optimum and tolerance values for the measured environmental variables were determined for 137 taxa with abundances and frequencies of occurrence above 1 %, and subsequent trophic indicator and sensitivity values were defined for the DDI. The correlation between the observed and the diatom-inferred nutrient concentrations was highest for phosphates ( ρ = 0.72). Significant statistical relationship were observed between DDI values and the chemistry-based General Quality Index values ( p = 0.006) and the specific pollution index (SPI) diatom metric ( p = 0.04). DDI has demonstrated a better correlation with water chemistry than SPI diatom metric. [ABSTRACT FROM AUTHOR]

Abstract: Gracilaria vermiculophylla (Ohmi) Papenfuss, an invasive Rhodophyta recently recorded in the Po Delta lagoons (May 2008), was also found in the Venice lagoon in March 2009 and successively in Pialassa della Baiona (Emilia–Romagna Region) in May 2009. The species has colonized the eutrophic and confined areas of Venice by pleustophytic tangled populations (5–15 kg fwt m−2), replacing the allochthonous species whereas it is absent in the areas characterized by low nutrient availability and high water exchange. In contrast, in the Po Delta lagoons and in Pialassa della Baiona it is present everywhere, also with high water renewal, because of the eutrophication caused by the Po river and the industrial area of Ravenna. This study presents the autoecology and distribution of G. vermiculophylla in the above environments, according to their different eutrophication status, showing its relationship with physico-chemical parameters and nutrient concentrations in water column, pore-water, surface sediments and particulate matter collected by traps in a station of the Venice lagoon (Teneri) sampled monthly during one year. Furthermore, we give new information on its morphology and the high dimorphism between female and male gametophytes and tetrasporophytes. [Copyright &y& Elsevier]

The Guadiamar riverbanks are home to riparian plant communities, such as alder, poplar and ash forests, tamujares, salt marshes, reed beds, etc. characteristic of Mediterranean rivers. A data set of these communities, including floristic relevés and environmental variables (physical and chemical soil properties, bioclimate) was analysed to correlate their floristic composition/species distribution with environmental variables. By means of an RDA (redundancy analysis) and a complementary cluster analysis four groups of species were discriminated according to their ecological requirements. The RDA displayed three major, parallel-running gradients (i.e., textural, bioclimatic and chemical) in environmental variables. Other less conspicuous, crossed gradients revealed the impact of man-made alterations, particularly in the middle reaches of the river. The results can be helpful in the planning of future ecologically oriented restoration programmes of wetlands. [ABSTRACT FROM AUTHOR]

In order to understand the causes underlying the Triassic–Jurassic (T/J) mass extinction, we tested different bivalve features for extinction selectivity, i.e. shell mineralogy, age at the Rhaetian and three main autoecologic traits (feeding mechanism, tiering and motility/attachment). Also, diversity and turnover rates throughout the Triassic and the Early Jurassic were analysed in detail. The dataset employed for this analysis was a precise database at genus level including data from Induan to Sinemurian times. Results point to a true mass extinction for bivalves around the T/J boundary. This extinction was not age-selective at the boundary. Certain analyses suggested that shell mineralogy was a character significantly increasing survival odds, but this relationship seems to reflect selectivity on autoecologic traits. There was no difference in extinction proportions between both feeding types (i.e. deposit feeders and filter feeders); among the other traits, deep burrowers, epifaunal-motile and endobyssate forms seem to have been favoured, while shallow burrowers (and probably reclined forms) were more heavily affected. This pattern suggests an environmental stress at the boundary with some particular issues affecting the different life modes. Models linking magmatism in the Central Atlantic Magmatic Province with the end-Triassic mass extinction are a plausible scenario for this kind of perturbation. [ABSTRACT FROM PUBLISHER]