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A pathways risk assessment is a part of an integrated assessment for the horizon scanning of non-indigenous species introductions. We examined past pathways, and their vectors, of aquatic NIS already present in Belarus in order to predict those species likely to spread to Belarus and arrive to Western Europe along the Central European invasion corridor. Twenty-four aquatic non-indigenous macroinvertebrates are known within Belarusian rivers, lakes and reservoirs, six of these have already spread westwards through Belarus. The modes of spread for these NIS were vessel transport, navigation corridors, and natural spread following an initial introduction.

Combined effects of cumulative nutrient inputs and biogeochemical processes that occur in freshwater under anthropogenic eutrophication could lead to myriad shifts in nitrogen (N):phosphorus (P) stoichiometry in global freshwater ecosystems, but this is not yet well-assessed. Here we evaluated the characteristics of N and P stoichiometries in bodies of freshwater and their herbaceous macrophytes across human-impact levels, regions and periods. Freshwater and its macrophytes had higher N and P concentrations and lower N : P ratios in heavily than lightly human-impacted environments, further evidenced by spatiotemporal comparisons across eutrophication gradients. N and P concentrations in freshwater ecosystems were positively correlated and N : P was negatively correlated with population density in China. These results indicate a faster accumulation of P than N in human-impacted freshwater ecosystems, which could have large effects on the trophic webs and biogeochemical cycles of estuaries and coastal areas by freshwater loadings, and reinforce the importance of rehabilitating these ecosystems.

Changes in land use and land cover (LULC) are the leading contributors to the decline and loss of ecosystem services in the world. The present study covered the Central Rift Valley lakes basin in Ethiopia, focusing on the valley floor and the East and West escarpments, to analyze changes in LULC and to estimate associated losses in ecosystem service values (ESVs). Covering both upstream and downstream areas in the basin, the study addressed major gaps in existing studies by connecting the sources and sinks of material (e.g., sediment and water) in source-to-lake systems. Additionally, the study facilitated the identification of critical areas for conserving natural resources and reversing the decline of associated ESVs in the Central Rift Valley. A post-classification comparison approach was used to detect LULC changes between 1973 and 2020 using four Landsat images from 1973, 1990, 2005 and 2020. The value transfer valuation method was used to estimate the changes in ESVs due to LULC changes. Among the seven major identified LULC classes, farmlands, settlements, and bare lands showed positive changes, while forestlands, grasslands, shrublands and waterbodies showed negative changes over the last 47 years. The expansion of farmlands, for example, has occurred at the expense of grasslands, forestlands and shrublands. The changes in LULC over a period of 47 years resulted in a total loss of US $62,110.4 × 106 in ESVs. The contributors to the overall loss of ESVs in decreasing order are provisioning services (US $33,795.1 × 106), cultural services (US $28,981.5 × 106) and regulating services (US $652.9 × 106). The results imply that addressing the degradation of land and water resources is crucial to reversing the loss of ecosystem services and achieving the national Sustainable Development Goals (SDGs) related to food and water security (SDGs 2 and 6) and life on land (SDG 15).

Arctic lowlands are characterized by large numbers of small waterbodies, which are known to affect surface energy budgets and the global carbon cycle. Statistical analysis of their size distributions has been hindered by the shortage of observations at sufficiently high spatial resolutions. This situation has now changed with the high-resolution (lt;5 m) circum-Arctic Permafrost Region Pond and Lake (PeRL) database recently becoming available. We have used this database to make the first consistent, high-resolution estimation of Arctic waterbody size distributions, with surface areas ranging from 0.0001 km 2 (100 m 2 ) to 1 km 2 . We found that the size distributions varied greatly across the thirty study regions investigated and that there was no single universal size distribution function (including power-law distribution functions) appropriate across all of the study regions. We did, however, find close relationships between the statistical moments (mean, variance, and skewness) of the waterbody size distributions from different study regions. Specifically, we found that the spatial variance increased linearly with mean waterbody size (R 2 = 0.97, p lt; 2.2e-16) and that the skewness decreased approximately hyperbolically. We have demonstrated that these relationships (1) hold across the 30 Arctic study regions covering a variety of (bio)climatic and permafrost zones, (2) hold over time in two of these study regions for which multi-decadal satellite imagery is available, and (3) can be reproduced by simulating rising water levels in a high-resolution digital elevation model. The consistent spatial and temporal relationships between the statistical moments of the waterbody size distributions underscore the dominance of topographic controls in lowland permafrost areas. These results provide motivation for further analyses of the factors involved in waterbody development and spatial distribution and for investigations into the possibility of using statistical moments to predict future hydrologic dynamics in the Arctic. © 2019 Muster, Riley, Roth, Langer, Cresto Aleina, Koven, Lange, Bartsch, Grosse, Wilson, Jones and Boike.

Communication of climate-responsive urban design guidelines is becoming increasingly relevant in the light of climate adaptation challenges in cities. Widespread uptake in practice of such guidelines can be promoted by visualizations of the principles on which they are based. The “Really cooling water bodies in cities” research project developed and tested the required knowledge on visual communication. Evidence-based design guidelines assisting designers with creating cooler urban water environments were developed and communicated with 3D animations. The animations were shaped according to three core theoretical criteria about visual representations: “visual clarity”, “trust” and “interest”. We assessed in how far these criteria were met in an inquiry with design professionals, the target group of the design guidelines. The article concludes with recommendations for developing visual design guidelines in climate-responsive urban design: to weigh the level of detail, components and balance between site-specificity/abstraction (“visual clarity”); to make microclimatic processes visible without distorting them (“trust”); and to keep timing short and visual attractiveness high (“interest”). It is argued that taking these aspects into account and setting a clear correspondence between theoretical concepts, representation objectives and options, can largely benefit visual design guidelines communicating climate-responsive urban design knowledge.

The study of phytoperiphyton communities in waterbodies and watercourses typical for the State Nature Reserve «Kivach» (Republic of Karelia, Russia) included the analysis of their taxonomy composition, ecology and space distribution such as abundance. In total, 156 species were identified from different substrates, belonging to Cyanophyta (Cyanoprokaryota) (21), Ochrophyta (96), Dinophyta (2), Euglenophyta (2), Chlorophyta (35). The paper has discussed the main principles of structure formation of phytoperiphyton communities in rivers. Based on the analysis of taxonomic composition and structure of attached algal communities the similarity features in community composition were revealed. The lists of species dominating in terms of abundance and biomass differ appreciably. Phytoperiphyton communities, dominated by typical attached forms such as Tabellaria flocculosa, Eunotia pectinalis Cocconeis placentula, and Achnanthes minutissima were most common and abundant. However, the bulk of biomass was formed mainly by the filamentous green algae Cladophora glomerata, Mougeotia sp., Zygnema sp., and Bulbochaete sp. We indicated that ecological-geographical composition of algae is dominated by widespread oligohalobic species being acidophilic or indifferent to medium pH. According to the assessments, water in lakes and one brook belonged to the oligosaprobic type and class II of water purity. Periphyton abundance and biomass in waterbodies studied ranging from 0.1 × 104 cell cm-2 to 1301.1 × 104 cell cm-2 and 0.01 mg/cm-2 to 34.70 mg/cm-2.

La gouvernance actuelle des plans d’eau au sein du territoire français par « masses d’eau » et « bassins versants » est le fruit d’une riche histoire, tant scientifique que réglementaire. Pourtant, elle se révèle insatisfaisante tant dans la prise en compte de la diversité limnologique que dans l’intégration de la question lentique au sein d’une démarche codifiée préférentiellement et partialement comme potamologique. Se pose alors la question de la pertinence des périmètres spatiaux usités. L’approche géographique géosystémique puis régionale par « territoire de l’eau » a permis de faire évoluer recherches et mentalités, mais la multiplicité de territoires générés constitue un frein contre la remise en cause de la toute-puissance des hydrauliciens. Pourtant, en intégrant pleinement les démarches systémiques et les approches des sciences sociales, il est possible de réfléchir à des formes de régionalisation malléables selon les critères et les époques et répondant davantage aux objectifs de « bon état de l’eau » fixés à l’échelle européenne. L’élargissement de la science limnologique aux étangs, mares et autres marais et non la prise en compte des seuls lacs ouvre en cela des perspectives nouvelles dans le cadre plus global du rôle de l’eau au sein des fluctuations climatiques. Appréhendant ainsi davantage la diversité morphologique et spatiale du corpus lentique, il s’avère alors possible d’observer des discontinuités tant systémiques que spatiales et ainsi disserter sur leurs origines ou leur caractère palimpseste. La territorialisation de ces relations Hommes-Milieux-Plans d’eau produit alors un nouveau concept, le territoire limnique, qui se veut opératoire., The current governance of bodies of water within French territory by "water masses" and "watersheds" is the result of a rich history, both scientific and regulatory. However, it proves unsatisfactory in its failure either to take into account limnological diversity or to integrate the lentic question within a codified approach which is preferentially and partially potamological. Hence, the question arises of the relevance of the spatial perimeters used. A geographical, geosystemical, then regional approach based around ‘water territories' has allowed research and mentalities to develop, but the multiplicity of territories generated constitutes a brake against the questioning of the power of hydraulic engineers. And yet, by fully integrating systemic approaches and those of the social sciences, it is possible to consider malleable forms of regionalization according to the criteria and periods and more appropriate to the objectives of "good water status" which have been set at the European level. The widening of limnological science to cover man-made lakes, ponds and other wetlands (instead of the only referring to lakes) opens new perspectives in the broader context of the role of water within the climatic fluctuations. Thereby gaining a broader understanding of the morphological and spatial diversity of the lentic corpus, it becomes possible to observe both systemic and spatial discontinuities and hence to discuss their origins or palimpsest character. The territorialization of these human-environment-body of water relationships thus produces a new concept, the limnic territory, which aims at being operational.

The European Union has implemented some of the most progressive conservation Directives in the world. These Directives are implemented in different ways, have different reporting cycles and use unique terminologies. The objectives of all the Directives require that the ecosystem based approach be applied when assessing the ‘status’ of the benthic environment. Benthic ecologists are faced with particular challenges when addressing the requirements of these Directives. Some anthropogenic activities in designated waterbodies can be difficult to monitor due to the variable nature of the environment in which they occur. Some of the newest forms of anthropogenic activities in the coastal environment may have significant impacts on local hydrographic regimes. This will require the relationship between the benthos and modified hydrodynamic conditions to be assessed. Large scale predictive models will be required to form baseline datasets for benthic communities within Ireland’s Exclusive Economic Zone (EEZ). Large scale mapping initiatives such as these are financially costly and it is important for benthic ecologists to understand the effectiveness of the available tools and resources prior to carrying out such studies. This thesis presents some new methods of benthic habitat assessment which can help to circumvent some of the key issues facing benthic ecologists working in response to EU Directives. We assess the effects of intertidal bivalve trestle cultivation on important bird feeding grounds in Natura 2000 sites. We present the Ecological Quality Ratio (EQR) Infaunal Quality Index (IQI) as an effective tool for assessing the risk posed to the conservation status of these sites. The potential effects of tidal energy extraction on epibenthic reef communities in a Natura 2000 site are assessed. Case studies are presented that assess the spatial and temporal effects of tidal turbine installation and operation. The relationship between epibenthic communities and a range of current velocities required to produce rated tidal energy are assessed. The turbulent wake of a tidal energy turbine was simulated and the relationship between epibenthic community structure and the simulated modified wake is assessed. We present the High Energy Hard Substrate (HEHS) index, a new EQR that was developed for use in animal-dominated, stable reefs, as an effective monitoring tool within tidal energy extraction sites. The effectiveness of hydrodynamic modelling and acoustically classified sediment data, as predictors of benthic biotopes was assessed using Galway Bay as a case study. This approach has potential application in mapping Irelands EEZ for the purposes of the Marine Strategy Framework Directive (MSFD).

Waterbodies such as lakes and ponds are abundant in vast Arctic landscapes and strongly affect the thermal state of the surrounding permafrost. In order to gain a better understanding of the impact of small-and medium-sized waterbodies on permafrost and the formation of thermokarst, a land surface model was developed that can represent the vertical and lateral thermal interactions between waterbodies and permafrost. The model was validated using temperature measurements from two typical waterbodies located within the Lena River delta in northern Siberia. Impact simulations were performed under current climate conditions as well as under a moderate and a strong climate-warming scenario. The performed simulations demonstrate that small waterbodies can rise the sediment surface temperature by more than 10 degrees C and accelerate permafrost thaw by a factor of between 4 and 5. Up to 70% of this additional heat flux into the ground was found to be dissipated into the surrounding permafrost by lateral ground heat flux in the case of small, shallow, and isolated waterbodies. Under moderate climate warming, the lateral heat flux was found to reduce permafrost degradation underneath waterbodies by a factor of 2. Under stronger climatic warming, however, the lateral heat flux was too small to prevent rapid permafrost degradation. The lateral heat flux was also found to strongly impede the formation of thermokarst. Despite this stabilizing effect, our simulations have demonstrated that underneath shallow waterbodies (

The concentrations of 8 elements (Fe, Mn, Cu, Cr, Ni, Zn, Pb and Cd) were determined in the water and liver by common carp (Cyprinus carpio L.) from 6 waterbodies in Stara Zagora region using atomic absorption spectrometry. Despite having a reputation for being heavily polluted, the investigated waters were not heavily burdened with examined metals. Our results suggest that fish liver were accumulating elements in the same manner such are increasing metal concentrations in waterbodies. Heavy metals concentrations were highest in the water and carp liver from Zagorka Lake and Ovcharitsa Dam, and especially of the Pb did exceed established quality standards for fish. Because the liver accumulates highest levels of heavy metals, it may to be use as an important biological indicator for ecological monitoring of the fish inhabiting waterbodies.