36 research outputs found
Biomass and species structure of the phytoplankton of an high mountain lake (Lake Paione Superiore, Central Alps, Italy)
In the framework of the EU MOLAR Project on “Measuring and modelling the dynamic response of remote mountain lake ecosystems to environmental change” a three whole-year study (1996-1998) on the composition and dynamics of phytoplankton community of the high mountain lake, acid sensitive Lago Paione Superiore (LPS) was carried out. The data were analyzed and compared with those gathered during the years 1991-1993. The phytoplankton was made up by nanoplanktonic unicellular algae, the only exception being the colonial Dinobryon sertularia. Just four species, belonging to Chrysophyceae (Chromulina sp., Dinobryon sertularia and Mallomonas alveolata) and to Dinophyceae (Gymnodinium sp.) were important as biomass and density, and they were always present throughout the year. The prevalence of potentially mixotrophic species suggests an adaptive strategy to the low environmental concentrations of inorganic carbon and phosphorus. The seasonal variations of the total biomass were similar to those observed in the previous years. The total number of species has increased; this could be related with the recent increase of the pH and of the alkalinity
Búsqueda de patrones en la comunidad fitoplanctónica de una laguna micromareal (Laguna de Venecia): evidencias en diez años de observación
By analysing a ten-year series (1998-2007) of data on hydrochemical properties, phytoplankton abundance and species composition in the Venice Lagoon, we identified i) the average annual phytoplankton biomass cycle, mainly unimodal and fairly well tuned with the fluctuations in temperature and irradiance and (ii) the seasonal succession of the most important species, allowing us to construct a “phytoplankton calendar”. Phytoplankton biomass was significantly lower in the second half of the ten-year period (2003-2007) than in the first half (1998-2002).A través del análisis de propiedades hidroquímicas, abundancia fitoplanctónica y composición de especies, en series de diez años (1998-2007), en la laguna de Venecia, se han identificado: i) Un promedio anual del ciclo de la biomasa prevalentemente de forma unimodal y bien sintonizada con las fluctuaciones de temperatura e irradiación; ii) Una composición cualitativa del fitoplancton que nos ha permitido realizar un “calendario del fitoplancton”; iii) Un decrecimiento en los últimos 5 años (2003-2007), de la biomasa con respecto a los 5 primeros años (1998-2003)
A macro-ecological approach to the study of the vulnerability of aquatic environments to nonindigenous species: a case study by the Virtual Research Infrastructure LifeWatch Italy
LifeWatch, the European Virtual Biodiversity Research Infrastructure, is a reference point for researchers, policy makers, public authorities and enterprises operating in the field of protection, management and the sustainable use of biodiversity and ecosystems. LifeWatch Italy has proposed a European-level case study designed to assess the vulnerability of aquatic and terrestrial ecosystems to the arrival of non-indigenous species (NIS), in order to demonstrate the functionality of the e-infrastructure and its potential. Here we present the results of a first analysis conducted, on a national scale, on NIS presence in various typologies of aquatic environments (freshwater, transitional and marine), aimed at verifying the link between vulnerability to NIS and human activities. Each of these environments is diversely affected by the NIS problem, which is of great interest both at national and international level, showing different rates of biodiversity alteration. To understand the mechanisms that cause the NIS success and to find adequate means of prevention, the LifeWatch community proposes a macro-ecological approach. It analyzes the drivers of NIS occurrence and the role played by climate change in facilitating their spread, so as to provide solutions that will lead to their reduction by applying effective measures for biodiversity conservation. The data used refer to a 30-year time span and include several taxonomic groups. All analyses were performed using dedicated R packages, which are one of the services provided by LifeWatch on the web
What is at stake for scientists when communicating ecology? Insight from the informal communication initiative “Cammini LTER”
What is at stake for scientists when communicating ecology? This is the basic question tackled in this paper, that we explored through reflections about an initiative of informal communication of ecological research called “Cammini LTER”: itineraries connecting a number of sites belonging to the Italian Long-Term Ecological Research network (LTER-Italy). LTER-Italy ecologists walked and cycled together with citizens creating a physical and visible movement of researchers ‘towards’ and ‘with’ citizens, aiming at providing the public with the opportunity to get familiar with Italian ecosystems, from the sea to alpine tundra. We address here the debates and the critical considerations among researchers themselves, stimulated by the overall experience, with focus on some relevant issues pertaining science communication, and even research production, evidencing the need for a cultural shift, which go far beyond the national context and the LTER – Italy network. Using a participant observations approach, through researchers’ words used to describe - formally and informally - the experience, we report and comment here the main narratives emerged, showing different attitudes of LTER researchers in Cammini towards the society and the role of ecology in it. Relationship and knowledge exchange appear crucial for communicating ecology, which can thus become an opportunity for building new qualities of knowledge and for creating a shared civic culture, able to make all players feel mutual responsible and contribute to the solution of particular socio-ecological challenges
Carbon partitioning in the food web of a high mountain lake: from bacteria to zooplankton
The organisms of the microbial loop in Lake Paione Superiore (LPS), a high mountain lake in the Italian Alpine region, were studied together with phytoplankton and zooplankton for three successive years. The biomass of bacteria, HNF (heterotrophic nanoflagellates), ciliates and phytoplankton, as mean carbon concentration in the three years, was 30 and 37 μg C l-1 near the surface (SUR) and the bottom (BOT) respectively. Under the ice-cover the mean biomass carbon decreased especially at the BOT, whereas at SUR the decrease was less evident due to the maintenance of higher phytoplankton biomass (mixotrophic flagellates). In LPS ~50% of the carbon was confined in bacteria, 20% in protozoa and 30% in phytoplankton. The ratio Autotrophs/Heterotrophs was lower than 1 (mean: 0,97 at SUR and 0,58 at BOT) thus indicating a system with a predominance of the heterotrophs. This might be the result of light inhibition of algal growth coupled to a production of dissolved carbon, utilized by bacteria. During late summer the peak of Daphnia longispina, the main component of the zooplankton of LPS, increased the carbon content in the lake to a total of 158 and 300 μg C l-1 in 1997 and 1998 respectively. At the late summer peaks, zooplankton represented from 78 to 89% of the total carbon of the pelagic communities. Furthermore, the presence of Daphnia could be responsible for a decrease in the biomass carbon of a variety of organisms (algae, protozoa and bacteria). It may be possible that this is an instance of zooplankton grazing on algae, protozoa and also bacteria, as Daphnia has very broad niches and may eat pico-, nanoplankton and small ciliates. In the oligotrophic LPS, a diet which also includes protozoa could give Daphnia a further chance of survival, as ciliates are an important source of fatty acids and sterols
Il dialogo dei ricercatori con la società civile: dalla Citizen Science ai Cammini LTER
Presentation of Cammini LTER at XXVIII Congresso dell’Associazione Nazionale dei Musei Scientifici. I musei Scientifici nell’anno europeo del patrimonio
Scientists’ attitudes about citizen science at Long-Term Ecological Research (LTER) sites
A profound transformation, in recent decades, is promoting shifts in the ways ecological science is produced and shared; as such, ecologists are increasingly encouraged to engage in dialogues with multiple stakeholders and in transdisciplinary research. Among the different forms of public engagement, citizen science (CS) has significant potential to support science-society interactions with mutual benefits. While many studies have focused on the experience and motivations of CS volunteers, scarce literature investigating the perspectives of researchers is available. The main purpose of this paper is to better understand scientists’ attitudes about CS in the context of its potential to support outcomes that extent beyond more traditional ones focused on promoting science knowledge and interest. We surveyed the scientific community belonging to the International Long-Term Ecological Research (ILTER) network because ILTER is of interest to multiple stakeholders and occurs over long time scales. Via an online questionnaire, we asked ILTER scientists about their willingness to participate in different types of public engagement, their reasons for participating in CS, the associated barriers, and any impacts of these efforts on them. Our findings show that many ILTER scientists are open to participating in CS for a wide range of reasons; the dominant ones involve deeper public engagement and collaboration. The barriers of greatest concern of these respondents were the lack of institutional support to start and run a CS project and the difficulty of establishing long-term stable relationships with the public. They reported impacts of CS activities on how they pursue their work and acknowledged the benefit of opportunities to learn from the public. The emerging picture from this research is of a community willing and actively involved in many CS projects for both traditional reasons, such as data gathering and public education, and expanded reasons that activate a real two-way cooperation with the public. In the ILTER community, CS may thus become an opportunity to promote and develop partnerships with citizens, helping to advance the science-society interface and to rediscover and enhance the human and social dimension of the scientific work
La Citizen Science e la Rete Italiana per la Ricerca Ecologica di Lungo Termine (LTER-Italia): esperienze nei siti d’alta quota
Spatial diversity of planktonic protists in the Lagoon of Venice (LTER-Italy) based on 18S rDNA
Transitional waters are subject to a high degree of variability in space and time. In this study, protist plankton communities of the Lagoon of Venice were compared among four sites characterised by different environmental conditions with a metabarcoding approach. High throughput sequencing (HTS) of the V4-18S rDNA fragment in 32 samples collected on four dates, from April 2016 to February 2017, produced 1,137,113 reads, which were grouped into 4,058 OTUs at 97% similarity. Bacillariophyta and Ciliophora were the most abundant groups in the entire dataset in terms of read number (27.6% and 16.6%, respectively), followed by Dinophyta (10.9%), Cryptophyceae (9.7%), and Syndiniales (6.1%). The contribution of protist groups markedly varied across the seasons, but spatial differences were also recorded in the lagoon. In April, a higher contribution of Bacillariophyta characterized St1 and 5 (68.0% and 61.1%), whereas Sts2 and 3 showed a higher percentage of Ciliophora (18.6 and 23.4%, respectively) and dinoflagellates (10.3 and 7.7%). In July, diatom blooms occurred at Sts1, 2 and 3, with some differences in the dominant species. At St2 Dinophyta reached the highest contribution of the whole sampling period in the area (30.6%), while St5 was quite distinct, with a low contribution of diatoms and a dominance of Ciliophora (34.0%) and Trebouxiophyceae (36.4%). All the stations in November were characterized by relatively high abundance of Ciliophora (21.4-51.9%). In February, diatom contribution was relevant only at St5 (29.3%), Teleaulax acuta peaked at St3 (ca. 36%), Syndiniales at St2 (38.8%) and Dictyochophyceae at St1 (24.2%). The α-diversity indexes (observed OTUs, Shannon and Pielou evenness) showed a high variability over space and time. Overall, diversity and community composition were rather similar between the intermediate and deeper Sts2 and 3 on all sampling dates whereas they at time differed between the landward and shallow Sts1 and 5. While the most marked differences occurred over the temporal scale, the depth of the station and the relatedness with the external marine coastal environment appear to play a major role in the spatial distribution of protist communities within the lagoon
Are we overlooking Natura 2000 sites? Lessons learned from a transnational project in the Adriatic Sea
Since the adoption of the Habitats and Birds Directives by EU governments, marine Natura 2000 (N2K) sites have been established in the European Mediterranean Sea, creating one of the largest international networks of protected areas. Nevertheless, to date, marine N2K sites are generally scarcely implemented, studied and monitored, and thus their management effectiveness is weak, and their environmental status is often unknown. The Interreg Italy-Croatia ECOSS project aimed at establishing the ECOlogical observing system of the Adriatic Sea (ECOAdS), to integrate the existing research and monitoring activities in the area, and to promote data sharing at international level, for enhancing monitoring and conservation in Adriatic N2K network. In the framework of ECOSS, a conceptual model was developed and applied to selected N2K sites, to review the existing knowledge, assess site effectiveness, and suggest possible improvements in their monitoring and management based on the contribution that ECOAdS can provide to their implementation. Information on social, ecological, and oceanographic elements related to the conservation and management of these case studies was gathered by consulting the project partners involved in the management and monitoring of the sites and through a literature review. The results of this study revealed a discouraging condition with no management plan in most of the sites, while regulatory measures are generally in place but without surveillance. Monitoring activities are performed occasionally, and information on presence and status of protected species is often lacking or outdated. Although the N2K network provides a unique opportunity to advance marine conservation and achieve the 30% conservation target by 2030, the biggest challenge ahead is the proper management and monitoring of N2K sites. The proposed conceptual model may be taken as a framework to properly set up ecological observing systems in the N2K network and help overcome current limitations, integrating scientific research within the N2K conservation strategies