scholarly journals The Influence of Flow Regime on Ecological Quality, Bird Diversity, and Shellfish Fisheries in a Lowland Mediterranean River and Its Coastal Area

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 918 ◽  
Author(s):  
Oscar Belmar ◽  
Carles Ibáñez ◽  
Ana Forner ◽  
Nuno Caiola
Keyword(s):  
Aquatic Vegetation ◽  
Environmental Flows ◽  
Ecological Status ◽  
Model Performance ◽  
Habitat Characteristics ◽  
Bird Diversity ◽  
Ecological Quality ◽  
Anthropogenic Pressures ◽  
Discharge Data ◽  
Mantis Shrimp

Designing environmental flows in lowland river sections and estuaries is a challenge for researchers and managers, given their complexity and their importance, both for nature conservation and economy. The Ebro River and its delta belong to a Mediterranean area with marked anthropogenic pressures. This study presents an assessment of the relationships between mean flows (discharges) computed at different time scales and (i) ecological quality based on fish populations in the lower Ebro, (ii) bird populations, and (iii) two shellfish fishery species of socioeconomic importance (prawn, or Penaeus kerathurus, and mantis shrimp, or Squilla mantis). Daily discharge data from 2000 to 2015 were used for analyses. Mean annual discharge was able to explain the variation in fish-based ecological quality, and model performance increased when aquatic vegetation was incorporated. Our results indicate that a good ecological status cannot be reached only through changes on discharge, and that habitat characteristics, such as the coverage of macrophytes, must be taken into account. In addition, among the different bird groups identified in our study area, predators were related to river discharge. This was likely due to its influence on available resources. Finally, prawn and mantis shrimp productivity were influenced up to a certain degree by discharge and physicochemical variables, as inputs from rivers constitute major sources of nutrients in oligotrophic environments such as the Mediterranean Sea. Such outcomes allowed revisiting the environmental flow regimes designed for the study area, which provides information for water management in this or in other similar Mediterranean zones.

scholarly journals Improvement of the esca index for the evaluation of ecological quality of coralligenous habitat under the european framework directives

2015 ◽  
Vol 16 (2) ◽  
pp. 419 ◽  
Author(s):  
L. PIAZZI ◽  
P. GENNARO ◽  
E. CECCHI ◽  
F. SERENA
Keyword(s):  
Spatial Variability ◽  
Ecological Status ◽  
Sampling Effort ◽  
Photographic Method ◽  
Ecological Quality ◽  
Anthropogenic Pressures ◽  
Small Scales ◽  
High Good ◽  
Different Sources

The ESCA (Ecological Status of Coralligenous Assemblages) index was recently developed to evaluate the ecological quality of coralligenous habitat. The study aims to improve the first index proposal through testing response to different sources of anthropogenic pressures and optimizing the sampling effort. ESCA was calculated on 14 sites and tested against a gradient of human pressures. Moreover, the main scales of spatial variability of assemblages were evaluated and values of index obtained with different sampling designs were compared. Results showed that studied sites resulted in high, good or moderate ecological status, according to an increasing gradient of the anthropization level. Values of ESCA index obtained with different methods have been compared and photographic method provides EQR values lower than destructive method. Spatial variability of assemblages was higher at large and small scales than at intermediate ones. Two locations for each study site and 20 replicated samples for each location may be consider the best sampling combination providing reliable values of ESCA index for the evaluation of ecological quality of coralligenous assemblages.

scholarly journals Evaluation of a Distributed Streamflow Forecast Model at Multiple Watershed Scales

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1279
Author(s):  
Tyler Madsen ◽  
Kristie Franz ◽  
Terri Hogue
Keyword(s):  
Local Population ◽  
Model Performance ◽  
Forecast Model ◽  
Hydrologic Model ◽  
Laboratory Research ◽  
Discharge Data ◽  
Distributed Hydrologic Model ◽  
Verification Period ◽  
Silver Spring

Demand for reliable estimates of streamflow has increased as society becomes more susceptible to climatic extremes such as droughts and flooding, especially at small scales where local population centers and infrastructure can be affected by rapidly occurring events. In the current study, the Hydrology Laboratory-Research Distributed Hydrologic Model (HL-RDHM) (NOAA/NWS, Silver Spring, MD, USA) was used to explore the accuracy of a distributed hydrologic model to simulate discharge at watershed scales ranging from 20 to 2500 km2. The model was calibrated and validated using observed discharge data at the basin outlets, and discharge at uncalibrated subbasin locations was evaluated. Two precipitation products with nominal spatial resolutions of 12.5 km and 4 km were tested to characterize the role of input resolution on the discharge simulations. In general, model performance decreased as basin size decreased. When sub-basin area was less than 250 km2 or 20–40% of the total watershed area, model performance dropped below the defined acceptable levels. Simulations forced with the lower resolution precipitation product had better model evaluation statistics; for example, the Nash–Sutcliffe efficiency (NSE) scores ranged from 0.50 to 0.67 for the verification period for basin outlets, compared to scores that ranged from 0.33 to 0.52 for the higher spatial resolution forcing.

scholarly journals The application of drones for mosquito larval habitat identification in rural environments: a practical approach for malaria control?

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Michelle C. Stanton ◽  
Patrick Kalonde ◽  
Kennedy Zembere ◽  
Remy Hoek Spaans ◽  
Christopher M. Jones
Keyword(s):  
Image Analysis ◽  
Malaria Control ◽  
Rural Areas ◽  
Near Infrared ◽  
Aquatic Vegetation ◽  
Temporal Trends ◽  
Scale Up ◽  
Larval Habitat ◽  
Habitat Characteristics ◽  
Rural Environments

Abstract Background Spatio-temporal trends in mosquito-borne diseases are driven by the locations and seasonality of larval habitat. One method of disease control is to decrease the mosquito population by modifying larval habitat, known as larval source management (LSM). In malaria control, LSM is currently considered impractical in rural areas due to perceived difficulties in identifying target areas. High resolution drone mapping is being considered as a practical solution to address this barrier. In this paper, the authors’ experiences of drone-led larval habitat identification in Malawi were used to assess the feasibility of this approach. Methods Drone mapping and larval surveys were conducted in Kasungu district, Malawi between 2018 and 2020. Water bodies and aquatic vegetation were identified in the imagery using manual methods and geographical object-based image analysis (GeoOBIA) and the performances of the classifications were compared. Further, observations were documented on the practical aspects of capturing drone imagery for informing malaria control including cost, time, computing, and skills requirements. Larval sampling sites were characterized by biotic factors visible in drone imagery and generalized linear mixed models were used to determine their association with larval presence. Results Imagery covering an area of 8.9 km2 across eight sites was captured. Larval habitat characteristics were successfully identified using GeoOBIA on images captured by a standard camera (median accuracy = 98%) with no notable improvement observed after incorporating data from a near-infrared sensor. This approach however required greater processing time and technical skills compared to manual identification. Larval samples captured from 326 sites confirmed that drone-captured characteristics, including aquatic vegetation presence and type, were significantly associated with larval presence. Conclusions This study demonstrates the potential for drone-acquired imagery to support mosquito larval habitat identification in rural, malaria-endemic areas, although technical challenges were identified which may hinder the scale up of this approach. Potential solutions have however been identified, including strengthening linkages with the flourishing drone industry in countries such as Malawi. Further consultations are therefore needed between experts in the fields of drones, image analysis and vector control are needed to develop more detailed guidance on how this technology can be most effectively exploited in malaria control.

Ecological Status Interactions for Assessing Bird Diversity in Relation to a Heterogeneous Landscape Structure

2013 ◽  
Vol 6 (1) ◽  
pp. 67-77 ◽  
Author(s):  
Djamel Bensizerara ◽  
Haroun Chenchouni ◽  
Abdelkrim Si Bachir ◽  
Moussa Houhamdi
Keyword(s):  
Landscape Structure ◽  
Ecological Status ◽  
Bird Diversity ◽  
Heterogeneous Landscape

scholarly journals Monitoring Skeletal Anomalies in Big-Scale Sand Smelt, Atherina boyeri, as a Potential Complementary Tool for Early Detection of Effects of Anthropic Pressure in Coastal Lagoons

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 159
Author(s):  
Chiara Leone ◽  
Francesca De Luca ◽  
Eleonora Ciccotti ◽  
Arianna Martini ◽  
Clara Boglione
Keyword(s):  
Early Detection ◽  
Habitat Degradation ◽  
Anthropogenic Impacts ◽  
Coastal Lagoons ◽  
Ecological Status ◽  
Detection Methods ◽  
Anthropogenic Pressures ◽  
Morphological Examination ◽  
Skeletal Anomalies

Mediterranean coastal lagoons are increasingly affected by several threats, all concurrently leading to habitat degradation and loss. Methods based on fish for the assessment of the ecological status are under implementation for the Water Framework Directive requirements, to assess the overall quality of coastal lagoons. Complementary tools based on the use of single fish species as biological indicators could be useful as early detection methods of anthropogenic impacts. The analysis of skeletal anomalies in the big-scale sand smelt, Atherina boyeri, from nine Mediterranean coastal lagoons in Italy was carried out. Along with the morphological examination of fish, the environmental status of the nine lagoons was evaluated using a method based on expert judgement, by selecting and quantifying several environmental descriptors of direct and indirect human pressures acting on lagoon ecosystems. The average individual anomaly load and the frequency of individuals with severe anomalies allow to discriminate big-scale sand smelt samples on the basis of the site and of its quality status. Furthermore, a relationship between skeletal anomalies and the environmental quality of specific lagoons, driven by the anthropogenic pressures acting on them, was found. These findings support the potentiality of skeletal anomalies monitoring in big-scale sand smelt as a tool for early detection of anthropogenic impacts in coastal lagoons of the Mediterranean region.

scholarly journals Factors affecting the species richness and composition of bird species in a community managed forest of Nepal

2021 ◽  
Vol 13 (9) ◽  
pp. 19212-19222
Author(s):  
Bishow Poudel ◽  
Bijaya Neupane ◽  
Rajeev Joshi ◽  
Thakur Silwal ◽  
Nirjala Raut ◽  
...  
Keyword(s):  
Diversity Index ◽  
Bird Species ◽  
Habitat Characteristics ◽  
Lower Percentage ◽  
Bird Diversity ◽  
Limited Information ◽  
Managed Forest ◽  
Point Count ◽  
Community Forests ◽  
Wiener Diversity Index

There exists limited information on biodiversity including avifaunal diversity and habitat condition in community forests (CF) of Nepal; thus we aimed to fulfill such gaps in Tibrekot CF of Kaski district. We used the point count method for assessing bird diversity and laid out a circular plot size of radius 5-m within 15-m distance from each point count station for recording the biophysical habitat characteristics. Bird species’ diversity, richness and evenness were calculated using popular indexes and General Linear Model (GLM) was used to test the respective effect of various biophysical factors associated with the richness of bird species. In total, 166 (summer 122, winter 125) bird species were recorded in 46 sample plots. The Shannon-Wiener diversity index was calculated as 3.99 and 4.09, Margalef’s richness index as 16.84 and 17.53 and Pielou’s evenness index as 0.83 and 0.84 for summer and winter, respectively. The influencing factors for richness of bird species were season (χ21, 90= 112.21; P= 0.016) with higher richness in the summer season and low vegetation cover (χ21, 89= 113.88; P= 0.0064) with higher richness in lower percentage cover. Thus, community managed forest should be protected as it has a significant role in increasing bird diversity, which has potential for attracting avifaunal tourism for the benefit of the local communities.

scholarly journals An environmental database for the status of freshwater in Greece

2013 ◽  
Vol 4 (1) ◽  
pp. 1-14
Keyword(s):  
National Level ◽  
Reference Conditions ◽  
Ecological Status ◽  
Anthropogenic Pressures ◽  
Environmental Pressures ◽  
Physico Chemical ◽  
Other Information ◽  
The Status ◽  
Freshwater Bodies ◽  
Status Data

An environmental database has been created, recording water bodies at a national level and assembling relevant data collected by various public services and institutions in charge of water resources management and research in Greece. Data consists of physico-chemical parameters, geomorphological descriptions, inventories of fauna and flora species, environmental pressures, vulnerability evaluation and other information useful for the assessment of current and future ecological status. Data gathering has proven to be a challenging task, due to the large number and the generally small size of the surface freshwater bodies as well as the numerous competent services and institutions and the multiple and sometimes conflicting responsibilities that therefore result. The latter is also partly the cause of lack of continuity of data, gaps or sometimes questionable reliability. Performing a global data overview, we note that (a) ecological status can be characterized as good for the majority of the sites, especially for small mountain streams, and (b) the general trend in most cases is degradation of current conditions, related either to anthropogenic pressures or to human activity combined with natural factors. This database, in a more completed and enriched form, could assist in the implementation of 2000/60/EC Directive in Greece and the establishment of reference conditions of surface freshwater systems.

scholarly journals KOSMOS: An Open Source Underwater Video Lander for Monitoring Coastal Fishes and Habitats

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7724
Author(s):  
Dominique Pelletier ◽  
Justin Rouxel ◽  
Olivier Fauvarque ◽  
David Hanon ◽  
Jean-Paul Gestalin ◽  
...  
Keyword(s):  
Work Experience ◽  
Collective Intelligence ◽  
Low Cost ◽  
Ecological Status ◽  
Digital Fabrication ◽  
Quality Data ◽  
Ecological Knowledge ◽  
Underwater Video ◽  
Anthropogenic Pressures ◽  
Technical Specifications

Background: Monitoring the ecological status of coastal ecosystems is essential to track the consequences of anthropogenic pressures and assess conservation actions. Monitoring requires periodic measurements collected in situ, replicated over large areas and able to capture their spatial distribution over time. This means developing tools and protocols that are cost-effective and provide consistent and high-quality data, which is a major challenge. A new tool and protocol with these capabilities for non-extractively assessing the status of fishes and benthic habitats is presented here: the KOSMOS 3.0 underwater video system. Methods: The KOSMOS 3.0 was conceived based on the pre-existing and successful STAVIRO lander, and developed within a digital fabrication laboratory where collective intelligence was contributed mostly voluntarily within a managed project. Our suite of mechanical, electrical, and software engineering skills were combined with ecological knowledge and field work experience. Results: Pool and aquarium tests of the KOSMOS 3.0 satisfied all the required technical specifications and operational testing. The prototype demonstrated high optical performance and high consistency with image data from the STAVIRO. The project’s outcomes are shared under a Creative Commons Attribution CC-BY-SA license. The low cost of a KOSMOS unit (~1400 €) makes multiple units affordable to modest research or monitoring budgets.

Hydrological modelling and anthropogenic water use

2021 ◽  
Author(s):  
Ponnambalam Rameshwaran ◽  
Ali Rudd ◽  
Vicky Bell ◽  
Matt Brown ◽  
Helen Davies ◽  
...  
Keyword(s):  
Climate Change ◽  
Water Use ◽  
Hydrological Model ◽  
Model Performance ◽  
River Flows ◽  
Discharge Data ◽  
New Approach ◽  
Water Demands ◽  
The Impact ◽  
Grid Based

<p>Despite Britain’s often-rainy maritime climate, anthropogenic water demands have a significant impact on river flows, particularly during dry summers. In future years, projected population growth and climate change are likely to increase the demand for water and lead to greater pressures on available freshwater resources.</p><p>Across England, abstraction (from groundwater, surface water or tidal sources) and discharge data along with ‘Hands off Flow’ conditions are available for thousands of individual locations; each with a licence for use, an amount, an indication of when abstraction can take place, and the actual amount of water abstracted (generally less than the licence amount). Here we demonstrate how these data can be used in combination to incorporate anthropogenic artificial influences into a grid-based hydrological model. Model simulations of both high and low river flows are generally improved when abstractions and discharges are included, though for some catchments model performance decreases. The new approach provides a methodological baseline for further work investigating the impact of anthropogenic water use and projected climate change on future river flows.</p>

Global BROOK90: validation, uncertainties, current progress and future outline.

2021 ◽  
Author(s):  
Ivan Vorobevskii ◽  
Rico Kronenberg
Keyword(s):  
Water Balance ◽  
Model Performance ◽  
Low Flow ◽  
Easy Access ◽  
Climate Projections ◽  
Seasonal Forecasts ◽  
Water Balance Components ◽  
Discharge Data ◽  
Small Catchment ◽  
Wide Range

<p>‘Just drop a catchment and receive reasonable model output’ – still stays as motto and main idea of the ‘Global BROOK90’ project. The open-source R-package is build-up on global land cover, soil, topographical, meteorological datasets and the lumped hydrological model as a core to simulate water balance components on HRU scale all over the world in an automatic mode. First introduced in EGU2020 and followed by GitHub code release including an publication of methodology with few examples we want to continue with the insights on the current state and highlight the future steps of the project.</p><p>A global validation of discharge and evapotranspiration components of the model showed promising results. We used 190 small (median size of 64 km<sup>2</sup>) catchments and FLUXNET data which represent a wide range of relief, vegetation and soil types within various climate zones. The model performance was evaluated with NSE, KGE, KGESS and MAE. In more than 75 % of the cases the framework performed better than the mean of the observed discharge. On a temporal scale the performance is significantly better on a monthly vs daily scale. Cluster analysis revealed that some of the site characteristics have a significant influence on the performance. Additionally, it was found that Global BROOK90 outperforms GloFAS ERA5 discharge reanalysis (for the category with smallest catchments).</p><p>A cross-combination of three different BROOK90 setups and three forcing datasets was set up to reveal uncertainties of the Global BROOK90 package using a small catchment in Germany as a case study. Going from local to regional and finally global scale we compared mixtures of model parameterization schemes (original calibrated BROOK90, EXTRUSO and Global BROOK90) and meteorological datasets (local gauges, RaKlida and ERA5). Besides high model performances for a local dataset plus a calibrated model and weaker results for ERA5 and the Global BROOK90, it was found that the ERA5 dataset is still able to provide good results when combined with a regional and local parameterization. On the other side, the combination of a global parameterization with local and regional forcings gives still adequate, but much worse results. Furthermore, a hydrograph separation revealed that the Global BROOK90 parameterization as well as ERA5 discharge data perform weaker especially within low flow periods.</p><p>Currently, some new features are added to the original package. First, with the recent release of the ERA5 extension, historical simulations with the package now are expanded to 1950-2021 period. Additionally, an alternative climate reanalysis dataset is included in the framework (Merra-2, 0.5x0.625-degree spatial resolution, starting from 1980). A preliminary validation shows insignificant differences between both meteorological datasets with respect to the discharge based model performance.</p><p>Further upgrades of the framework will include the following core milestones: recognition of forecast and climate projections and parameter optimization features. In the nearest future we plan to utilize full power of the Climate Data Store for easy access to seasonal forecasts (i.e. ECMWF, DWD, NCEP) as well as climate projections (CMIP5) to extend the package’s scope to predict near and far future water balance components.</p>

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