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Changes in Alpine grassland of Gran Paradiso National Park (Italy): first results from CO2 fluxes monitoring programme
No full textThe alpine grassland of Gran Paradiso National Park (Italy) resulted from centuries of human activities that created high biodiversity semi-natural areas below the timberline. The progressive abandonment of management practices as well as climate change lead to variations in species diversity. In order to apply active management actions for maintaining such ecosystem, a long-term monitoring programme started in 2016 in selected sites of the Park, aimed to: 1) evaluate the effects of a well managed grazing system on animal and plant biodiversity; 2) compare the evolution of managed and non-managed areas, the latter obtained by excluding a portion of the meadows from grazing. Together with CO2 fluxes, monitoring includes also plant community, invertebrates, soil properties. We present the first results of spatial and temporal variability of CO2 fluxes from grasslands in relation to air temperature, radiance and soil properties
Effects of protection status, climate, and water mana gement of rice fields on long-term population dynamics of herons and egrets in north-western Italy.
No full textThe long-term population trends (1972-2015) of the herons and egrets breeding in NW Italy were analysed spatially and temporally in relation to environmental and human-related variables. Ardea cinerea and Egretta garzetta increased till 2000 but then began to decrease, mainly in the region of intensive rice cultivation, where the trend was likely driven by reduced flooding of the paddies, the main foraging habitat. Colony site availability is currently not limiting. These results are being applied to develop a strategy for the conservation of the colonies in the remaining wetlands of NW Italy
Stochastic downscaling of precipitation in complex orography: a simple method to reproduce a realistic fine-scale climatology
No full textStochastic rainfall downscaling methods usually do not take into account orographic effects or local precipitation features at spatial scales finer than those resolved by the large-scale input field. For this reason they may be less reliable in areas with complex topography or with sub-grid surface heterogeneities. Here we test a simple method to introduce realistic fine-scale precipitation patterns into the downscaled fields, with the objective of producing downscaled data more suitable for climatological and hydrological applications as well as for extreme event studies. The proposed method relies on the availability of a reference fine-scale precipitation climatology from which corrective weights for the downscaled fields are derived. We demonstrate the method by applying it to the Rainfall Filtered Autoregressive Model (RainFARM) stochastic rainfall downscaling algorithm. The modified RainFARM method is tested focusing on an area of complex topography encompassing the Swiss Alps, first, in a perfect-model experiment in which high-resolution (4km) simulations performed with the Weather Research and Forecasting (WRF) regional model are aggregated to a coarser resolution (64km) and then downscaled back to 4km and compared with the original data. Second, the modified RainFARM is applied to the E-OBS gridded precipitation data (0.25? spatial resolution) over Switzerland, where high-quality gridded precipitation climatologies and accurate in situ observations are available for comparison with the downscaled data for the period 1981-2010. The results of the perfect-model experiment confirm a clear improvement in the description of the precipitation distribution when the RainFARM stochastic downscaling is applied, either with or without the implemented orographic adjustment. When we separately analyze grid points with precipitation climatology higher or lower than the median calculated over the neighboring grid points, we find that the probability density function (PDF) of the real precipitation is better reproduced using the modified RainFARM rather than the standard RainFARM method. In fact, the modified method successfully assigns more precipitation to areas where precipitation is on average more abundant according to a reference long-term climatology. The results of the E-OBS downscaling show that the modified RainFARM introduces improvements in the representation of precipitation amplitudes. While for low-precipitation areas the downscaled and the observed PDFs are in good agreement, for high-precipitation areas residual differences persist, mainly related to known E-OBS deficiencies in properly representing the correct range of precipitation values in the Alpine region. The downscaling method discussed is not intended to correct the bias which may be present in the coarse-scale data, so possible biases should be adjusted before applying the downscaling procedure
ReadLet: an ICT platform for the assessment of reading efficiency in early graders
No full textReading is not just word decoding, but the joint product of decoding and deep linguistic comprehension [ 1 , 2 ]. Effective linguistic comprehension relies on language skills such as semantic and syntactic awareness. Both decoding and linguistic comprehension are necessary for reading comprehension, and neither is by itself sufficient [ 2 ]. However, current protocols for reading assessment measure decoding (reading accuracy and speed) and reading comprehension separately [ 3 , 4 , 5 ]. This does not allow evaluation of reading efficiency [ 6 ], defined as the ability to fully understand connected texts by minimising reading time, a cognitive ability that lies at the roots of students\u27 academic achievement [ 8 , 7 ]. ReadLet is an ICT platform specifically designed to provide accurate, evidence-based assessment of reading efficiency in early grade children, by offering an ecological, non-invasive protocol for extensive data elicitation, storage and analysis. With ReadLet, early graders at school can read a one or two page text displayed on a tablet touchscreen, either silently or aloud. Children are asked to slide their finger across the words as they read, to guide directional tracking. After reading, the child is prompted with a few multiple-answer questions on text content presented one at a time, while the text remains displayed on the screen for the child to be able to retrieve relevant information. In the process, the tablet keeps track of time-aligned multimodal data: voice recording, finger sliding time, time of reading, time of question answering, and number of correct answers. Data are recorded, stored locally, sent to the ReadLet server through an internet connection, and processed remotely by a battery of cloud-based services, analysing data automatically to produce a detailed quantitative signature of each reading session. A server-based database aggregates anonymised data to make them available for specialists. Also individual\u27s longitudinal profiles are stored, for them be queried and inspected upon authorised access. The platform combines portable ICT technology and cloud computing with a number of modality-specific software modules, implemented as web services including: i) a text processing and readability assessment service, consisting in a battery of tools for automated linguistic annotation of written texts and a machine-learning component assigning a readability score to annotated texts [ 9 ]; ii) a finger touch processing service aligning the child\u27s finger sliding with the written text and measuring speed fluctuations; iii) a speech processing and decoding assessment service, aligning the acoustic record of child\u27s reading with the written text and assessing correctness of recoding [ 10 ]. At the time of writing, the platform includes the first two modules only. Preliminary testing of a prototype version of ReadLet technology with a population of about 200 pupils aged 8 to 11, both male and female, varying for socio-economic status, language (Italian, French and Arabic) and geographical area (Italy and Morocco), showed that children are extremely responsive to using a tablet for reading, and very easy to engage in what they perceive as an enjoyable experience. We expect online databases of automatically classified cross-sectional and longitudinal data, accurate statistical modelling and developmental trends of reading literacy to help education professionals and clinical specialists assess the level of reading skills reached by the child, and decide which intervention programmes and measures are most appropriate. While information technology cannot and should not supplant the role and professional judgement of teachers and therapists, the project intends to provide portable tools, models and data for timely screening and daily management of reading difficulties and disorders
Il Lago di Tovel. Memorie, documenti e sedimenti
No full textIl Lago di Tovel si trova in Trentino, sula destra orografica della Val di Non, incastonato tra le cime delle Dolomiti del Brenta. Il caratteristico fenome dell\u27arrossamento delle acque lo ha reso famoso nel mondo e terreno di ricerca per molti eminenti studiosi di limnologia nel corso del Novecento. Le fonti documentarie e i reperti naturali relativi a questo caratteristico specchio d\u27acqua, conservati dall\u27Istituto per lo Studio degli Ecosistemi del CNR; hanno permesso di ricostruire le campagne di studio svolte a Tovel tra il 1938 e il 1940. Da quell\u27epoca la ricerca non si ? mai interrotta, proseguendo anche dopo la fine del fenomeno dell\u27arrossamento (1964). Nel libro viene pubblicato anche il diario delle campagne condotte da Edgardo Baldi, che ci restituisce una vera e propria "istantanea" del suo metodo e modus operandi. La modernit? del suo approccio, che prevedeva l\u27utilizzo di un laboratorio per l\u27osservazione di campioni in vivo, ha permesso la raccolta di una documetazione scientifica di straordinario valore e la costituzione del Museo del Plancton dell\u27Istituto
Genome analysis of the freshwater planktonic Vulcanococcus limneticus sp. nov. reveals horizontal transfer of nitrogenase operon and alternative pathways of nitrogen utilization
No full textBackground Many cyanobacteria are capable of fixing atmospheric nitrogen, playing a crucial role in biogeochemical cycling. Little is known about freshwater unicellular cyanobacteria Synechococcus spp. at the genomic level, despite being recognised of considerable ecological importance in aquatic ecosystems. So far, it has not been shown whether these unicellular picocyanobacteria have the potential for nitrogen fixation. Here, we present the draft-genome of the new pink-pigmented Synechococcus-like strain Vulcanococcus limneticus. sp. nov., isolated from the volcanic Lake Albano (Central Italy). Results The novel species Vulcanococcus limneticus sp. nov. falls inside the sub-cluster 5.2, close to the estuarine/marine strains in a maximum-likelihood phylogenetic tree generated with 259 marker genes with representatives from marine, brackish, euryhaline and freshwater habitats. V.limneticus sp. nov. possesses a complete nitrogenase and nif operon. In an experimental setup under nitrogen limiting and non-limiting conditions, growth was observed in both cases. However, the nitrogenase genes (nifHDK) were not transcribed, i.e., V.limneticus sp. nov. did not fix nitrogen, but instead degraded the phycobilisomes to produce sufficient amounts of ammonia. Moreover, the strain encoded many other pathways to incorporate ammonia, nitrate and sulphate, which are energetically less expensive for the cell than fixing nitrogen. The association of the nif operon to a genomic island, the relatively high amount of mobile genetic elements (52 transposases) and the lower observed GC content of V.limneticus sp. nov. nif operon (60.54%) compared to the average of the strain (68.35%) support the theory that this planktonic strain may have obtained, at some point of its evolution, the nif operon by horizontal gene transfer (HGT) from a filamentous or heterocystous cyanobacterium. Conclusions In this study, we describe the novel species Vulcanococcus limneticus sp. nov., which possesses a complete nif operon for nitrogen fixation. The finding that in our experimental conditions V.limneticus sp. nov. did not express the nifHDK genes led us to reconsider the actual ecological meaning of these accessory genes located in genomic island that have possibly been acquired via HGT
Rapid assessment of ecological integrity for LTER wetland sites by using UAV multispectral mapping
No full textLong-term ecological research (LTER) sites need a periodic assessment of the state of their ecosystems and services in order to monitor trends and prevent irreversible changes. The ecological integrity (EI) framework opens the door to evaluate any ecosystem in a comparable way, by measuring indicators on ecosystem structure and processes. Such an approach also allows to gauge the sustainability of conservation management actions in the case of protected areas. Remote sensing (RS), provided by satellite, airborne, or drone-borne sensors becomes a very synoptic and valuable tool to quickly map isolated and inaccessible areas such as wetlands. However, few RS practical indicators have been proposed to relate to EI indicators for wetlands. In this work, we suggest several RS wetlands indicators to be used for EI assessment in wetlands and specially to be applied with unmanned aerial vehicles (UAVs). We also assess the applicability of multispectral images captured by UAVs over two long-term socio-ecological research (LTSER) wetland sites to provide detailed mapping of inundation levels, water turbidity and depth as well as aquatic plant cover. We followed an empirical approach to find linear relationships between UAVs spectral reflectance and the RS indicators over the Do?ana LTSER platform in SW Spain. The method assessment was carried out using ground-truth data collected in transects. The resulting empirical models were implemented for Do?ana marshes and can be applied for the Braila LTSER platform in Romania. The resulting maps are a very valuable input to assess habitat diversity, wetlands dynamics, and ecosystem Productivity as frequently as desired by managers or scientists. Finally, we also examined the feasibility to upscale the information obtained from the collected ground-truth data to satellite images from Sentinel-2 MSI using segments from the UAV multispectral orthomosaic. We found a close multispectral relationship between Parrot Sequoia and Sentinel-2 bands which made it possible to extend ground-truth to map inundation in satellite images
Automatic extraction of shoreline from satellite images: a new approach
No full textNo abstract availabl
How will climate change affect endangered Mediterranean waterbirds?
No full textGlobal warming and direct anthropogenic impacts, such as water extraction, largely affect water budgets in Mediterranean wetlands, thereby increasing wetland salinities and isolation, and decreasing water depths and hydroperiods (duration of the inundation period). These wetland features are key elements structuring waterbird communities. However, the ultimate and net consequences of these dynamic conditions on waterbird assemblages are largely unknown. We combined regular sampling of waterbird presence through one annual cycle with in-situ data on relevant environmental predictors of waterbird distribution to model habitat selection for 69 species in a typical Mediterranean wetland network in southwestern Spain. Species associations with environmental features were subsequently used to predict changes in habitat suitability for each species under three climate change scenarios (encompassing changes in environmental predictors that ranged from 10% to 50% change as predicted by regional climatic models). Waterbirds distributed themselves unevenly throughout environmental gradients and water salinity was the most important gradient structuring the distribution of the community. Environmental suitability for the guilds of diving birds and vegetation gleaners will decline in future climate scenarios, while many small wading birds will benefit from changing conditions. Resident species and those that breed in this wetland network will also be more negatively impacted than those using this area for wintering or stopover. We provide a tool that can be used in a horizon-scanning framework to identify emerging issues in waterbird conservation and to anticipate suitable management actions
Threats of Climate Change to Single-Island Endemic Species in Protected Areas
No full textThe Island of La Palma (Canary Islands, Spain) is protected as a whole (La Palma World Biosphere Reserve) and within this frame in parts as a national park (Caldera de Taburiente) and additionally through sites of special conservation status, and Natura 2000 sites. The island hosts a large number of archipelago endemic (AE) plant species and also single-island endemic (SIE) plants. These species even contribute substantially to local species richness, biomass and functioning of ecosystems, and they cannot be replaced through species from other regions. In consequence, there is an urgent need to detect spatial patterns and changes in the distribution and performance of these species in order to adapt the management of Protected Areas to the increasing pressures. Here, we present together with local administrative management a detailed analysis of the contribution of endemic species and of the respective threats that need to be addressed in adaptation strategies. Also we show how monitoring and the control of success can be implemented with the support of Earth Observation. The study is part of the H2020 Project ECOPOTENTIAL