Land-Based Impact of Nutrient Loads and Eutrophication on an Ancient Mediterranean Natural Lake

In water management plans, all human impacts on the aquatic environment are quantified and evaluated. For this purpose, lake-related assessment methods of watersheds are needed. The aim of this study is to present the environmental condition along the watershed–lake continuum of Lake Baratz, located in the northeastern part of Sardinia. We provide a method to evaluate the impact of a small watershed area on the trophic state of this ancient Mediterranean natural lake. This study demonstrates the potentialities of coupling simple land structure-based models with empirical ones, allowing one to hierarchize, interpret, and predict the relationships among the watershed ecological unity and lake trophic conditions at multiple spatial and temporal scales. It also demonstrates how the impact of single and interacting nutrient stressors can have a different impact on the trophic status which, in particular, applies to autotrophs, constituting a key response in the ecosystem. We suggest that the stressor hierarchy should be considered as a way of prioritizing actions in the cost-effective implementation of conservation and management plans.

Electrochemical Surface-Enhanced Raman Spectroscopy (EC-SERS): A Tool for the Identification of Polyphenolic Components in Natural Lake Pigments

The identification of natural organic pigments is important for the conservation, preservation, and historical interpretation of artwork. Due to the fugitive nature of the natural dye components in pigments, their...

Status of fish diversity in Surha Taal, a natural lake in the floodplains of river Ganga, in Ballia District, Uttar Pradesh, India

The study presents the status of fish diversity, abundance and habitat structure of Surha Lake, which is a perennial and natural lake fed by the river Ganga. The study was conducted between 2011 to 2013 covering pre and post-monsoon seasons. In total, 4,852 individual fish specimens were collected representing 66 fish species belonging to 23 families. The species diversity comprised 65 species in pre-monsoon and 60 species in post-monsoon season (p<0.05). The highest species diversity was recorded for the family Cyprinidae (22), followed by Bagridae (7). An assessment of conservation status of 66 fish species as per IUCN Red List 2019 criteria listed 6 species under near threatened (NT), 54 under least concern (LC) and two species under vulnerable (VU) category. The study reports several commercially important species under near threatened (Chitala chitala, Labeo pangusia, Ompok bimaculatus, Ompok pabda, , Ailia coila and Bagarius bagarius), which makes Surha Taal an important natural lake from fishery management point of view. The study also prioritised different habitat types important for different species. The slow water in the mid-channel areas of the lake were categorised as important habitats for near threatened and vulnerable fish species like C. chitala, B. bagarius and Wallago attu, which can be prioritised for population level management.

Data Lake Governance: Towards a Systemic and Natural Ecosystem Analogy

The realm of big data has brought new venues for knowledge acquisition, but also major challenges including data interoperability and effective management. The great volume of miscellaneous data renders the generation of new knowledge a complex data analysis process. Presently, big data technologies provide multiple solutions and tools towards the semantic analysis of heterogeneous data, including their accessibility and reusability. However, in addition to learning from data, we are faced with the issue of data storage and management in a cost-effective and reliable manner. This is the core topic of this paper. A data lake, inspired by the natural lake, is a centralized data repository that stores all kinds of data in any format and structure. This allows any type of data to be ingested into the data lake without any restriction or normalization. This could lead to a critical problem known as data swamp, which can contain invalid or incoherent data that adds no values for further knowledge acquisition. To deal with the potential avalanche of data, some legislation is required to turn such heterogeneous datasets into manageable data. In this article, we address this problem and propose some solutions concerning innovative methods, derived from a multidisciplinary science perspective to manage data lake. The proposed methods imitate the supply chain management and natural lake principles with an emphasis on the importance of the data life cycle, to implement responsible data governance for the data lake.

STATUS PREDICTION BY 3D FRACTAL NET CNN BASED ON REMOTE SENSING IMAGES

The contradiction between the supply and demand of water resources is becoming increasingly prominent, whose main reason is the eutrophication of rivers and lakes. However, limited and inaccurate data makes it impossible to establish a precise model to successfully predict eutrophication levels. Moreover, it is incompetent to distinguish the degree of eutrophication status of lakes by manual calculation and processing. Focusing on these inconveniences, this study proposes 3D fractal net CNN to extract features in remote sensing images automatically, aiming at achieving scientific forecasting on eutrophication status of lakes. In order to certificate the effectiveness of the proposed method, we predict the state of the water body based on remote sensing images of natural lake. The images in natural lake were accessed by MODIS satellite, cloud-free chlorophyll inversion picture of 2009 was resized into [Formula: see text] patches, which were collected as training and testing samples. In the total of 162 pictures, our study makes three consecutive pictures as a set of data so as to attain 120 group of training and 40 testing data. Taking one set of data as input of the neural network and the next day’s eutrophication level as labels, CNNs act considerable efficiency. Through the experimental results of 2D CNN, 3D CNN and 3D fractal net CNN, 3D fractal net CNN has more outstanding performance than the other two, with the prediction accuracy of 67.5% better than 47.5% and 62.5%, respectively.

High resolution sediment microfabric and geochemical analysis reveals seasonal scale redox mineralisation, anthropogenic environmental change and pollution in England's largest natural lake - Windermere

&lt;p&gt;Many lakes in industrialised areas have undergone anthropogenically driven eutrophication and increases in pollution leading to decreased water and sediment quality. In some cases, these effects are enhanced by seasonally changing lake redox conditions that may act to concentrate potentially toxic elements sufficiently to exceed internationally recognised Sediment Quality Standards, impacting key species and jeopardizing water supply.&amp;#160; A combined, geochemical and sediment microfabric analysis is applied to reconstruct the history of cultural eutrophication and pollution in the North and South Basins of Windermere, England&amp;#8217;s largest natural lake. We also document a record of seismicity and link increased sedimentation rates and sediment instability. The onset and development of eutrophication in Windermere occurred from the mid-19th to the early 20th centuries.&amp;#160; Raised lake productivity is indicated by an increase in sedimentary &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C, and increased pollution by elevated sedimentary trace metals (Pb, Zn, Cu, Hg, and As), likely enhanced by incorporation and adsorption to settling diatom aggregates, preserved as sedimentary laminae. In the South Basin of the lake, contemporaneous increasing sediment &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N values also occur in step with increasing Zn, Hg, Cu from this time, linking metal enrichment to the input of isotopically heavy nitrate (N) from anthropogenic sources including sewage. From around 1930, a decrease in Mn and Fe-rich laminae indicate reduced deep water ventilation, and increased incidence of sediment anoxia, being most intense in the deeper North Basin where benthic activity intermittently ceased. Strongly reducing conditions in the sediment promoted Fe and Mn reduction and the formation of unusual Pb-bearing barite, hitherto only described from toxic mine wastes and contaminated soils. In the North Basin cores a clay rich laminae dated 1979-1980 is shown to be a mass transport deposit linked to large scale slope failure likely caused by the 4.7 ML 1979 Carlisle earthquake. Slope failure was exacerbated by preconditioning principally by increased sedimentation as a result of anthropogenic activities. From 1980 there was a partial recovery in oxygenation with Mn and Fe rich laminae returning in some parts. But in the South Basin, the continued impacts of sewage discharge is indicated by elevated &amp;#948;&lt;sup&gt;15&lt;/sup&gt;N of organic matter. Imaging and X-ray microanalysis using scanning electron microscopy has enabled the identification of seasonal-scale redox mineralisation of Mn, Fe and Ba related to intermittent sediment anoxia. Elevated concentrations of Mn, Fe, Ba, and As also occur in the surficial sediment and provide evidence for dynamic redox mobilisation of potentially toxic elements that may be released to the lake waters. Concentrations of As, in particular, exceed international Sediment Quality Standards. These surface enrichments in As and other toxic elements may become more prevalent in the future with climate change driving lengthened summer stratification in the lake.&lt;/p&gt;