Identifying and quantifying global change impacts on biotic and abiotic components of ecosystems is critical to promote an effective adaptation that increases the success of conservation strategies. To achieve this goal, global and regional assessment efforts require certain degree of harmonization on local monitoring programs to establish relevant comparisons at different spatio-temporal scales. Otherwise, the lack of harmonization might hinder the detection and assessment on the effects of human impacts. In this work we have compiled information on freshwater monitoring programs located in areas of intensive research and conservation interest: International Long Term Ecological Research (ILTER) nodes and mountain National Parks. We aimed at evaluating the quality and robustness of these programs to assess the impact of global change, addressing from the worldwide to the European and Spanish national scale. Results highlighted that freshwater monitoring programs lack a common strategy to monitor these ecosystems. Even at the continental and national scales, contrasting strategies and level of detail have been historically applied. Water quality, habitat and biodiversity are more commonly monitored than community structure and ecosystem functioning. Monitoring efforts on the Spanish Mountain National parks indicated differences on the targeted aquatic ecosystems. Rivers and lakes received a higher attention, while mires were rarely considered. Our results provide evidence that greater efforts should be directed towards constructing a coordinated strategy to monitor freshwater ecosystems at national, continental, and global scales. This strategy should involve a shared backbone of biophysical and biogeochemical variables for each habitat type on agreed protocols that are implemented across regions and administrative borders. Achieving this will support a substantial advance on the ecological research to further delineate proper conservation strategies to face the challenges imposed by global change.
Monitoring changes in the areal extent and geographic distribution of wetland vegetation has become more critical considering the impact of anthropogenic and climate changes. We compared the capabilities of the optical space-borne sensors Sentinel-2 and WorldView-3 (WV3) to distinguish between wetland and terrestrial vegetation for improved reporting to the Sustainable Development Goal (SDG) sub-indicator 6.6.1a, and also map different wetland vegetation communities for two catchments in the Grassland Biome of South Africa. Ground truthing of vegetation communities was conducted between 2016 and 2018. A Random Forest classification algorithm was used with a 100-fold cross-validation to assess mean accuracies using all combinations of bands, a digital elevation model generated from fine-scale contours, spectral vegetation indices (VIs) and above-ground biomass (AGB). Five and eight wetland vegetation classes were mapped for Hogsback and Tevredenpan, respectively, of a total of 13 classes for each of the sites. Wetland and terrestrial vegetation were found to be highly separable, with overall accuracies (OAs) attaining 91–99% and individual user's accuracies 88–99% for both sensors and study areas. Even though the wetland vegetation communities consisted of a mosaic of smaller communities, monodominant species and plant functional type classes, they were found to be highly separable across sensors and study areas. The highest average OA of 83% for Hogsback's wetland vegetation communities was achieved using WV3 bands with elevation, AGB and the VIs, while the Sentinel-2 bands, elevation, AGB and VIs attained an average OA of 78%. For Tevredenpan, the use of the Sentinel-2 bands and elevation achieved the highest mean OA of 79% for the classification of wetland vegetation communities, while the WV3 (in this case the short-wave infrared bands were not available owing to shortage of funding) maximized at 74%. The inclusion of elevation data and spectral indices in the classification scenarios of wetland vegetation communities increased the OA by 4–17%. Omitting the red-edge and shortwave infrared bands for classification of vegetation classes resulted in a varied response across sensors and study areas, but decreased the OA by 4.8–7.3% when using the Sentinel-2 sensors. These results show promise for improved reporting and monitoring of the extent and types of palustrine wetlands in the Grassland Biome of South Africa using freely-available Sentinel-2 data.
The micro algal diversity in relation to salinity changes in Swamithope saltpans, Kanyakumari district, Tamil Nadu was studied. Algal samples were collected during pre-monsoon of 2015 from creek (source water), three different ponds i.e. holding, evaporation and crystallizing besides recording of salinity. The study indicated that Bacillariophyta members were dominant in creek (source water), while Cyanophyta members were dominant in both holding and evaporation ponds. Dunaliella, a Chlorophyta was the single species occurred in the crystallizing ponds.
Sirodotia huillensis (Welwitsch ex W and G. S. West) Skuja is a well known and a common freshwater red alga; it was collected from the submerged stones of streams near the forest farm lands of the R. Udayagiri ranges of Orissa state, India. It was mostly reported from Western Ghats of India and it has been recorded for the first time in Eastern Ghats. In the present paper, the morphology and reproductive structures of S. huillensis i.e., male and female thallai, branching pattern, spermatia on primary and secondary laterals, asymmetrical carpogonia, distinctly stalked trichogyne and indistinct carposporophyte with globular to obovoid shaped carposporangium are described in detail.
Background: Oscillatoria princeps has been reported from various parts of India for its diversity but not studied in detail about morphology and reproduction hence we try to fill that lacuna. Methods: Samples were collected from a stream near Kanyakumari district, Tamil Nadu. One part was preserved in 4% formalin, while the other part was brought to unialgal culture by streaking method. The cultures were grown and maintained in ASN III (-NaCl) medium at the photoperiodic culture racks with 8 hours light and 16 hours dark. Semipermanent slides were prepared and Leica EC3 Microsystems was used for observation and documentation. Findings: The alga was dark blue green in colour, growing in clusters at the bottom of the stream. Individual filaments were blue green to olive green in colour. Mature trichome straight, cells much broader than long with distinct cross walls. Apical cells hemispherical with keritomized content. Individual cells were round in shape and the size varies from 57.60µm to 69.05µm in width and 5.20µm to 9.55µm in length thus the ratio of length and breadth as 1:8. When such cells were stacked one above the other it gives “stack of poker chips” appearance, characteristic feature of the species. Notches were found at the inner side of the cell corresponding to the slit on the trichome. When such cells were stacked one above the other, it results in the crack like appearance on the trichome. One to three notches / slits were observed in the present study. Reproduction both by fragmentation and hormogonia (formation of separation disc) was observed. Application/Improvements: The new finding like cracks/ slit like structure on trichome can be taken for further studies. The microphotographs will enable the researchers to have better understanding.
The population dynamics of fish in northern lakes is strongly influenced by climatic factors. In this study, we investigated whether there is a link between the late 1980s climate regime shift in Europe and the collapse of vendace (Coregonus albula) population at the same time in Lake Peipsi. Until the end of the 1980s, vendace was very abundant in the lake, but then its catches sharply declined. This decline inspired investigations into the extreme weather events preceding the vendace collapse using data on daily water temperatures and ice phenology together with commercial fishery statistics since 1931 and test catch data since 1986. We identified using advanced statistical methods that the hot summer of 1988, which was accompanied by a severe cyanobacterial bloom and extensive fish kill, and the subsequent non-permanent ice cover and early ice-offs in 1989 and 1990 in Lake Peipsi were the main reasons for the disappearance of vendace from catches in 1991. Moreover, a negative correlation appeared between catches of the predatory pikeperch (Sander lucioperca) and vendace. Predation pressure as well as fish habitat degradation caused by lake eutrophication may contribute to the instability of the vendace population too. Our study showed that extreme weather events such as heat waves in summer and non-permanent ice-cover in winter in consecutive years may have long-lasting harmful effects on the population abundance of cool-water fish species such as vendace whose eggs usually develop under an ice cover in north-temperate lakes.
The first survey data on the fisheries in Lake Peipsi were collected by natural scientist Karl Ernst von Baer as a result of the world's first special fishery expedition in 1851–1852. In the current study, all available numerical datasets on fishing in Lake Peipsi from 1851 to 2018 have been drawn together in order to analyse the long-term changes in the lake’s fish assemblages. As the study indicates, the overexploitation, catching of juvenile fish and predator–prey imbalance have been common problems associated with fisheries in Lake Peipsi for the last two centuries. Similar to many inland waterbodies worldwide, total catch of fish from Lake Peipsi has decreased about four times since the mid-19th century, and the catch of lake (dwarf) smelt, a previously dominant species, has periodically fluctuated with long-term gradual reduction. The decline of cool-water fish, such as vendace, burbot and Peipsi whitefish during the last two centuries, and the domination of Eurasian perch, common bream and pike-perch in the catches of the last 20 years mark considerable structural shifts in fish assemblages. Of the multiple stressors (e.g., nutrient enrichment, increased water temperature, overfishing) triggering shifts in fish assemblages, the impact of climate warming, especially extreme weather events such as heatwaves, seems to be the strongest during the last three decades. However, none of the fish species have completely disappeared from the lake during the last century although the share of cool-water fish in the total catch has declined about tenfold since the 1930s.
This contribution applies the “mean tem-perature of the catch” (MTC) concept of Cheung et al. (Nature 497:365–368, 2013) to fish catch data for Lake Peipsi, Estonia/Russia, covering the years 1931 to 2019. The preferred temperature of each of the ten target fish species was obtained from the literature, and combined with the species-specific catch data to obtain MTC values for each year. The analysis of the MTC time series thus obtained with a segmented regression yielded two trend lines, one horizontal at 14.5 °C (1931–1986), and the other (1987–2019) ascending with a slope 0.85 °C·decade−1. Overall, the segmented regression model explains over half of the variance of the MTC data set (multiple R2 = 0.53; adjusted R2 = 0.51). Lake surface water temperatures correlate with MTC, even though weakly (r = 0.30), when considering a 2-year time lag. The fish community of the shallow Lake Peipsi reacts more strongly to temperature changes than marine ecosystems so far studied using the MTC.
The most robust approach to ecological monitoring and assessment is the use of regionally calibrated indicators. These should be calculated based on collocated biological (response) and physicochemical (stressor) variables and an objective rating and scoring system. In developing countries, a frequent lack of financial and technical resources for monitoring has led to many environmental problems being overlooked, such as the degradation of streams, rivers, and watersheds. In this paper, we propose the Karun Macroinvertebrate Tolerance Index (KMTI) for application to rivers in the Karun River basin, which is the largest watershed in Iran, draining semi-arid mountainous regions. The KMTI is the first biological index specifically developed and calibrated for Iranian water resources. Benthic macroinvertebrates, physical habitat, hydromorphic, and water quality data were collected and measured at 54 sites across four seasons in 2018 and 2019. A total of 101 families of benthic macroinvertebrates belonging to eight classes and 21 orders were identified, and tolerance values were determined for 95 families. The KMTI was found to be most efficient in identifying ecological degradation when data were used from winter samples with a discrimination efficiency (DE) 90% and a four-season mean of 84.3%. Also, the best DE of the water quality classification table based on the KMTI index was equal to 86.9%.
Although environmental filtering and spatial structuring are commonly regarded as two key factors shaping community dynamics, their relative contribution remains unknown for numerous aquatic ecosystems, particularly highly dynamic floodplain lakes. This issue is here addressed by examining the seasonal metacommunity dynamics of freshwater fishes in Lake Dongting, a large subtropical lake of the middle Chang-Jiang basin in southern China. Physicochemical variables and fish assemblages were recorded at 20 sampling sites during the wet, normal and dry seasons. Distance-based redundancy analysis and associated variation partitioning were used to examine the relative role of environmental variables and spatial factors in fish community assembly in each season. Analysis results demonstrated that the relative contribution of environmental filtering and spatial structuring varied depending on environmental features and the extent of hydrological connectivity in different seasons. Intensified physicochemical parameters in the dry season convinced the enhanced environmental filtering; whereas high hydrological connectivity in the wet season favored the stronger spatial process. Specifically, the community assembly processes were temporally dynamic; spatial structuring (or mass effects), resulting from excessively high dispersal rates, was dominant during the flooding season, environmental filtering was stronger than spatial structuring (or dispersal limitation) during the non-flooding season. These findings highlight the importance of conserving local habitats of Lake Dongting during the dry and normal season, and maintaining of the flood pulse of the lake and its natural variability during the wet season. Apparently, the construction of a water-level regulation project at the Chenglingji Channel, the outlet watercourse of Lake Dongting, is not supported because it will change the flood pulse of this lake and thus impact habitat heterogeneity or variability.
The monitoring of wetland extent is a global imperative, considering loss of ecosystem services and conservation value. To date, the understanding of the variation in the extent of lacustrine (inundated) wetlands has been limited, based on intermittently available, coarse-scale imagery. The aim of this study was to assess the capabilities of the freely available Sentinel-2 sensor in monitoring inundated wetlands. In particular, to demonstrate the ability to determine the maximum extent of inundation for reporting on the Sustainable Development Goal (SDG) 6.6 (Clean Water and Sanitation) and SDG 15.1 (i.e., halting biodiversity loss), the functional diversity and the hydrological regime of depressions were explored in the Mpumalanga Lake District (MLD) of South Africa. Using the monthly inundation data derived from Sentinel-2 images between January 2016 and May 2018, the results showed that the maximum extent of open water can be successfully reported for SDG 6.6. Lacustrine wetlands constituted about 47 of the 416 (but 66% of the total areal extent of) depressions in the MLD, while others were predominantly palustrine (vegetated). The functional diversity varied from predominantly (61% of the extent of) inundated depressions to seasonally (3%) inundated depressions. The Sentinel-2 sensor was able to detect intra- and inter-annual variation of the extent of inundation, making it suitable to monitor these wetlands for global and climate change impacts.
Length-weight relationships (LWR) for seven species from the Karun River system in Iran were provided. These species include Alburnus doriae, Alburnus sellal, Barbus karunensis, Capoeta coadi, Squalius berak, Turcinoemacheilus saadii and Rhinogobius lindberg. Fishes were collected in November and December 2018 and LWR is based on total length and weight of 2867 specimens calculated by equation W= aL b. The b value ranged from 2.92 to 3.25 and r 2 from 0.94 to 0.99. The length and weight range is presented for each species collected in the Karun River Basin. Citation: Zare-Shahraki, M.; Keivany, Y.; Ebrahimi, E.; Bruder, A.; Flotemersch, J. & Blocksom, K.A. 2020. Length-weight relationships of seven fish species from the Karun River system, southwestern Iran. Iranian Journal of Ichthyology 7(4): 352-355.
The study of community structure changes in relation to environmental gradients can help assessing and predicting community response to anthropogenic disturbances; however, such types of studies are rare in semi-arid regions. This study aimed at investigating the macroinvertebrate community composition in response to environmental variables in rivers of a semi-arid mountainous region, i.e., the Zagros mountain range, southwestern Iran. Environmental variables and macroinvertebrates were sampled at 54 sites in four seasons during 2018–2019. A total of 101 families of benthic macroinvertebrates from 8 classes and 21 orders were identified. Diversity and evenness indices showed significant temporal variation (p < 0.05). Also, taxa richness and Ephemeroptera, Plecoptera, and Trichoptera taxa showed strong seasonal stability, whereas spatial variation among all metrics was significantly different (p < 0.05). Taxa richness and density weekly correlated with altitudinal gradient. Correlation analysis, cluster analysis, non-metric multidimensional scaling, and canonical correspondence analysis demonstrated associations between community composition and environment variables, including definition of site groupings according to aggregated quality estimates. The results suggest that both physico-chemical variables of water (nitrate, total dissolved solids, Escherichia coli, temperature, chemical oxygen demand, and dissolved oxygen) and habitat structure (wetted river width, altitude, and riffles presence) determined the community composition of macroinvertebrates. Seasonal variation of community indices and community composition in our region seemed to differ from those estimated from subarctic, temperate and subtropical ecosystems. Our study provides a strong basis for further research, planning, and conservation of macroinvertebrate communities in the Karun River basin and similar river systems in the region.
A physical, chemical and biological characterization of river systems is needed to evaluate their ecological quality and support restoration programs. Herein, we describe an approach using water chemistry, physical structure and land use for identification of a disturbance gradient existing in the Karun River Basin. For this purpose, at each site, physical structure and physico-chemical data were collected once in each season for a total of 4 samples during the period (October 2018 - September 2019). Principal components analysis (PCA) of 17 variables identified five variables that were influential across all seasons: conductivity, total habitat score, stream morphology, clay & silt, and sand. Of the 54 sites, 14, 26 and 14 sites were classified as least, moderate and most disturbed sites, respectively. The metric Ephemeroptera, Plecoptera and Trichoptera (EPT) taxa was used for validation of the classification. Results in different seasons showed that all the least disturbed sites (n = 14) were significantly different from moderate and most disturbed sites (p < 0.01). In this study the validation process presented a good confirmation of a priori reference sites selection process, showing that the proposed criteria could be considered as appropriate tools for characterization of the existent disturbance gradient in the Karun River Basin.
Latin America’s tremendous socio-cultural and biological diversity has evolved along tightly intertwined, far-reaching river networks. Decisions taken by any one country, may have strong impacts on the regional and even global biodiversity conservation agenda, such as the Convention on Biological Diversity. Here we comment on four perspectives complementing actions suggested by Azevedo-Santos et al. (2021) in their Commentary “Conservation of Brazilian freshwater biodiversity: Thinking about the next 10 years and beyond”. This contribution aims at attaining an effective conservation of freshwater biodiversity in Latin America, particularly in the context of the ongoing negotiations on the Global Biodiversity Framework. Our suggestions put forward cross-border perspectives, urging governments to engage in actions that consider the reality of and threats to transnational ecosystems such as many river basins of Latin America and elsewhere.
EXPERT INPUT TO THE POST-2020 GLOBAL BIODIVERSITY FRAMEWORK: TRANSFORMATIVE ACTIONS ON ALL DRIVERS OF BIODIVERSITY LOSS ARE URGENTLY REQUIRED TO ACHIEVE THE GLOBAL GOALS BY 2050
The degree of coupling between the social and ecological components of social-ecological systems is seen as fundamental to understanding their functioning, interactions and trajectories. Yet, there is limited work about how to empirically understand the degree of coupling between social and ecological systems, nor the processes by which the degree of coupling could change over time. Here, we introduce a conceptual framework for characterizing trajectories over time of coupling and de-coupling in social-ecological river systems. We analyze two conceptual scenarios describing coupling and de-coupling trajectories in a social-ecological system and define a series of key concepts for understanding social-ecological system trajectories. We tested these coupling and de-coupling trajectories theory by linking these concepts to empirical case examples of two river social-ecological systems in the western United States. Finally, we propose a quantitative approach with the potential for evaluating the level of social-ecological coupling and de-coupling trajectories in other SES contexts. This paper represents an advancing on the identification of specific actions that explain current SES trajectories and immediate actions to reinforce or shift the trajectory.
Exploitation of hydropower potential in alpine areas undermines the ecological integrity of rivers. Damming and water abstraction substantially alter the physical habitat template of rivers, with strong repercussions on aquatic communities and their resources. Tools are needed to predict and manage the consequences of these alterations on the structure and functioning of macroinvertebrate communities and resource availability in alpine streams. We developed habitat preference models for taxa, functional feeding guilds, and organic resources to quantify the effects of dis-charge alteration on macroinvertebrate communities in two alpine streams. Our physical habitat model related an indirect measure of bottom hydraulic forces (FST hemispheres) to the distribution of macroinvertebrate taxa and their resources. We observed that flow-dependent habitat availa-bility for macroinvertebrate communities generally decreased with increasing water abstraction. We were able to relate these changes to near-bed hydraulic conditions. Our results suggest, how-ever, the existence of upper discharge thresholds delimiting optimal habitat conditions for taxa. In contrast, we found weak effects of near-bed hydraulic conditions on resource distribution. Over-all, our findings contribute towards predicting the impacts of water abstraction on macroinverte-brate communitiesassemblages in small alpine streams and the benefits of baseflow restoration.
• Freshwater biodiversity is declining at an unprecedented rate. Freshwater conservationists and environmental managers have enough evidence to demonstrate that action must not be delayed but have insufficient evidence to identify those actions that will be most effective in reversing the current trend. • Here, the focus is on identifying essential research topics that, if addressed, will contribute directly to restoring freshwater biodiversity through supporting ‘bending the curve’ actions (i.e. those actions leading to the recovery of freshwater biodiversity, not simply deceleration of the current downward trend). • The global freshwater research and management community was asked to identify unanswered research questions that could address knowledge gaps and barriers associated with ‘bending the curve’ actions. The resulting list was refined into six themes and 25 questions. • Although context-dependent and potentially limited in global reach, six overarching themes were identified: (i) learning from successes and failures; (ii) improving current practices; (iii) balancing resource needs; (iv) rethinking built environments; (v) reforming policy and investments; and (vi) enabling transformative change. • Bold, efficient, science-based actions are necessary to reverse biodiversity loss. We believe that conservation actions will be most effective when supported by sound evidence, and that research and action must complement one another. These questions are intended to guide global freshwater researchers and conservation practitioners, identify key projects and signal research needs to funders and governments. Our questions can act as springboards for multidisciplinary and multisectoral collaborations that will improve the management and restoration of freshwater biodiversity.
This study was carried out on periphytic cyanobacteria and algae assemblages of microbial mats in streams and small water bodies during the Antarctic summer of 2019 in the vicinity of Ecology Glacier (King George Island, Antarctica). The significantly diversified assemblages between the microbial mats of small water bodies and streams were observed. The higher biomass and proportion of periphytic cyanobacteria with Planktothix agardhii as dominant species were found in the streams at lower mean water temperature and higher nutrient content while diatoms generally dominated in the small water bodies (primarily Fragilaria capucina ). Chlorophyta also reached a significant proportion in the total biomass of periphyton with dominant species of Prasiola crispa and Keratococcus mucicola. The growth of periphytic cyanobacteria and algae was determined mainly by type of substrate, water temperature and nutrient concentrations. The results also suggest the phenomenon of nutrient uptake by these assemblages from the waters, confirmed by the negative correlations between some species and nutrients (TN, TP, N-NH 4 , P-PO 4 ). A large share of commonly occurring periphytic species and limitation of typically polar ones, suggest progressive changes in the eutrophication of Antarctic waters caused by the global climate change and increased pollution in the environment. Therefore, these areas should be subject to a special legal protection, preceded by detailed research of these ecosystems.
Latin America’s tremendous socio-cultural and biological diversity has evolved along tightly intertwined, far-reaching river networks. Decisions taken by any one country, may have strong impacts on the regional and even global biodiversity conservation agenda, such as the Convention on Biological Diversity. Here we propose and illustrate four perspectives that complement the actions suggested by Azevedo-Santos et al. (2021) to contribute to the effective conservation of freshwater biodiversity in Latin America, particularly in the context of the post-2020 Global Biodiversity Framework, currently under negotiation among the parties. Our suggestions put forward cross-border perspectives, urging governments to engage in actions, objectives, monitoring elements and post-2020 indicators that consider the reality of and threats to transnational ecosystems such as many river basins of Latin America.
Pronounced organism-wide morphological stasis in evolution has resulted in taxa with unusually high numbers of primitive characters. These ‘living fossils’ hold a prominent role for our understanding of the diversification of the group in question. Here we provide the first detailed osteological analysis of Aenigmachanna gollum based on high-resolution nano-CT scans and one cleared and stained specimen of this recently described snakehead fish from subterranean waters of Kerala in South India. In addition to a number of derived and unique features, Aenigmachanna has several characters that exhibit putatively primitive conditions not encountered in the family Channidae. Our morphological analysis provides evidence for the phylogenetic position of Aenigmachanna as the sister group to Channidae. Molecular analyses further emphasize the uniqueness of Aenigmachanna and indicate that it is a separate lineage of snakeheads, estimated to have split from its sister group at least 34 or 109 million years ago depending on the fossil calibration employed. This may indicate that Aenigmachanna is a Gondwanan lineage, which has survived break-up of the supercontinent, with India separating from Africa at around 120 mya. The surprising morphological disparity of Aenigmachanna from members of the Channidae lead us to erect a new family of snakehead fishes, Aenigmachannidae, sister group to Channidae, to accommodate these unique snakehead fishes.
The Karun River, western Iran, is the largest (catchment area of 57’059 km2) and the only navigable river system in Iran. It flows westwards out of the Zagros mountain range (max. altitude 4409 m.a.s.l.), traverses the Khuzestan plain, and joins the Shatt al-Arab, which then enters the Persian Gulf. The freshwater ecosystems of the Karun are affected by various uses of its water and catchment (i.e. agriculture, rural development, aquaculture and hydropower facilities) but the impacts of these activities on fish and macroinvertebrate communities is largely unknown. This is particularly problematic, because the Zagros mountain range is the heart of the Irano-Anatolian Biodiversity Hotspot. As part of a collaborative project between Iranian and Swiss research groups, we investigated fish and macroinvertebrate communities and the abiotic conditions at 53 lotic sites in the entire river system in spring and summer 2019. Sites ranged from small high-altitude creeks to large lowland rivers, the latter often affected by various anthropogenic pressures. Pristine abiotic conditions were mainly restricted to small high-altitude sites, which had low chemical pollution and excellent habitat features (in particular with low fine sediment deposition, natural channel morphology and intact riparian vegetation). Fishes were sampled in all habitats of the respective sites by backpack electro fishing and benthic macroinvertebrates on ten transects per site using kick-netting and surber sampling. Samples were preserved in formaldehyde and transferred to the laboratory for identification. We identified 36 fish species and 77 macroinvertebrate families. Fish communities were dominated by cyprinids (65.2%; mainly Capoeta coadi, Garra rufa, Capoeta aculeata) and macroinvertebrate communities by chironomids (46.39%), both taxa being relatively insensitive to habitat degradation. Overall, we observed significant correlations between fish and macroinvertebrate communities in terms of various diversity indices (based on species richness and evenness) and overall abundance, suggesting similar community responses of both organism groups to the anthropogenic and natural gradients in the Karun. Specifically, we measured highest fish diversity in large lowland river reaches despite being rather polluted, thus pointing at positive effects of connectivity and habitat heterogeneity, but probably also of introductions, for biodiversity. Rare endemic fish species (e.g. benthic species such as Sasanidus kermanshahensis, Oxynoemacheilus freyhofi, Turcinoemacheilus hafezi and Turcinoemacheilus saadii) were restricted to relatively clean headwater sites characterized by coarse sediment and high flow velocity. We measured highest macroinvertebrate diversity in sites with excellent habitat features albeit moderate chemical quality. In particular, we observed highest EPT diversity (the orders Ephemeroptera, Plecoptera, Trichoptera, comprising many sensitive species) in riffle sites characterized by cobble sediment and high flow velocity. Findings from our project will contribute to the management and conservation of freshwater biodiversity in this region, which currently undergoes major environmental changes due to human population growth, increasing resource demands and climate change.
In the present study, the actual fish fauna of the upper Kura and Aras river drainages in Turkey were reexamined. The distribution and latest taxonomic status of the species were assessed. The study area comprises the upper part of Kura and Aras river drainages, in Turkey. Overall, 32 sampling sites were prospected between 2004-2018 to inventory fish species in the area and a total of 33 species were recognized, five of which are recorded for the first time from the Turkish part of upper Aras river drainage, namely Alburnus hohenackeri, Blicca bjoerkna, Gobio artvinicus, Neogobius fluviatilis and Rhodeus amarus.
Alburnoides turani, new species, from the Filyos River drainage is described and the distribution of the nine other Alburnoides species known from the southern Black Sea basin is revised. Alburnoides turani is distinguished by having a naked ventral keel, or the keel is covered with 1-3 scales between the posterior pelvic-fin base and the anus, an interorbital distance wider than the eye diameter and the snout length, 48-55 total lateral-line scales, 5-6 scale rows between the anal-fin origin and the lateral line, 13½-14½ branched anal-fin rays, and 41-42 total vertebrae.
Cantonati M., Stevens L., Pringle C.M., Turak E. & Poikane S. (Guest Eds.). (2017-)2020. Multiplicity, characteristics, main impacts, and stewardship of natural and artificial freshwater environments: Consequences for biodiversity conservation. Water 9-12. Virtual Special Issue. 14 papers. https://www.mdpi.com/journal/water/special_issues/freshwater_biodiversity_conservation The rationale of this Virtual Special Issue (VSI) was to collect papers that discuss the potential of the different natural and artificial freshwater habitat types to contribute to freshwater biodiversity conservation. We were especially seeking articles illustrating the potential of near-natural and man-made freshwater habitats (focus could be narrowed on ecological categories, e.g., phytobenthos- or taxocoenoses, etc.) for biodiversity conservation by examining their ecological characteristics, conservation status, and main impacts affecting them. We thus aimed at addressing the multiplicity of still and running freshwater environments (Cantonati et al. 2020; introductory paper), from headwaters down to large rivers and lakes (papers published in the VSI are cited in the following): groundwater and dependent ecosystems, springs and spring-fed streams (Taxböck et al. 2017, Zelnik et al. 2018, Lai et al. 2019, Rossini et al. 2020, Stevens et al. 2020, Taxböck et al. 2020), headwaters (Richardson 2019), glacial streams (Füreder & Niedrist 2020), streams, large rivers, ancient and large lakes, high-mountain lakes, oxbow lakes, reservoirs, urban freshwater habitats (Turak et al. 2020), mires (Marazzi et al. 2019), small wetland ecosystems (Bolpagni et al. 2019), Boreal and Arctic freshwater habitats (fwh), Antarctic fwh, Mediterranean fwh, tropical fwh (Seeteram et al. 2019), arid-climate fwh. Keywords: Near-natural freshwater habitats, man-made freshwater habitats, freshwater biodiversity, conservation ecology, biodiversity inventorying, environmental-quality assessments, water-level fluctuations (WLF).
Reptiles are rarely included in urban freshwater biodiversity monitoring and conservation. We explored the global persistence of freshwater dependent turtles, lizards, crocodilians and snakes in cities with a population greater than 100,000 using species occurrence data in online databases from a five-year period (2013-2018). We then used ecological niche models to help identify the locations of suitable habitats for three freshwater reptile species in Sydney, Australia. Our Global analysis showed that sightings of a majority of known species of crocodilians and freshwater turtles were recorded in databases within this 5-year period in contrast to about one in three freshwater lizard species and one in ten freshwater snake species and that freshwater reptiles were observed within 50 km of the center of 40% of the 3525 cities. While global databases hold substantial recent species occurrence records for some regions, they contain very little data for large parts of the world. Modelling showed that potential suitable habitat for the three freshwater species in Sydney was distributed across areas with different levels of urban development. The persistence of populations of freshwater reptiles in and around a large proportion of the world's cities show that this group can play an important role in urban biodiversity conservation.
Design and testing of a replicable, scalable capacity-building model for species conservation - Volume 50 Issue 4 - Haidy Rojas, Dinora Sánchez, Daniel Lew, José R. Ferrer-Paris, Jon Paul Rodríguez, J. Celsa Señaris, Grisel Velásquez, Douglas Rodríguez-Olarte, Carliz Díaz
Reproduction of fishes in flooding events of Portuguesa River, Venezuela The reproduction of fishes in flooding events in the Portuguesa River, Venezuela, is reported. In the high plainlands (about 100 meter above sea level) and only at specific water speeds (higher than 0.59 m/s) eggs presenting embryonic stages between the four-cell-embryo and the phase of independent movement of the embryo were collected, suggesting that reproductive events occurred in a specific section of river associated to the geomorphological transition from foothills to the high plainlands. The eggs were incubated in laboratory and it was obtained mainly species of Characiformes and Siluriformes which are migratory fishes that make local movements of ascent and descent at the time of flooding. Two basic aspects in the reproduction of fishes during floods are considered: magnitude of the water flow and areas of flood downstream. The regional fluvial ecosystems are put under severe impacts (dams, deforestation) that affect the survival of great part of ichthyofauna that reproduces during events of flooding. A special management of the section of the Portuguesa River is suggested where the reproductive events take place.
O sapê já foi muito utilizada pela comunidade indígena da Terra Buriti, em Dois Irmãos de Buriti, e devido ao intenso extrativismo ocorreu a supressão populacional. O objetivo deste trabalho foi avaliar possíveis efeitos aleloquímicos em germinação de sementes de alface repolhuda e rabanete Crisom Giant. Para o experimento foram utilizadas placas de Petri de 15 cm de diâmetro contendo papel de filtro umedecido com água destilada e solução etanólica de extrato de sapê. O tratamento controle consistiu de sementes embebidas com água destilada. A contagem de germinação foi realizada diariamente, sendo consideradas germinadas aquelas que apresentaram emissão da radícula. Medidas de crescimento inicial de plântulas dos tratamentos foram realizadas com uso de régua milimetrada. O extrato de sapê inibiu a germinação de sementes de alface e rabanete. Apenas 3,3 % de germinação de sementes de alface em extrato de sapê, enquanto no tratamento controle germinaram 98,6%. Em rabanete a germinação de sementes tratadas com extrato etanólico de sapê foi de 38,8%, em relação ao controle (89,9%). A planta de sapê possui propriedades químicas que podem ser usadas como controle biológico nas áreas de plantio de agricultura familiar da aldeia Buriti.
Substâncias promovem perdas germinativas que podem inibir o desenvolvimento normal de plântulas. Embora, pesquisas já foram realizadas com herbicidas contra plantas de sapê, não foram encontrados estudos de alelopatia. O objetivo deste estudo foi avaliar potencial efeito de extrato de sapê no desenvolvimento de plântulas e na diminuição da germinação de sementes de alface e rabanete. Foram utilizadas placas de Petri de 15 cm de diâmetro contendo papel filtro umedecido com água destilada e solução etanólica de extrato de sapê. Cada repetição recebeu 5 ml de extrato etanólico, sendo 2 tratamentos para cada espécie alvo. Em cada repetição foram utilizadas 30 sementes, sendo 3 placas por tratamento, no total de 6 repetições para cada espécie. O tratamento controle consistiu de sementes embebidas apenas em água destilada. A contagem de germinação foi realizada diariamente. O extrato de sapê inibiu a germinação de sementes de alface repolhuda (Lactuca sativa) e de rabanete (Crisom giant). Apenas 3,3 % de germinação de sementes de alface em extrato de sapê, enquanto no tratamento controle germinaram 98,6%. Em rabanete a germinação de sementes tratadas com extrato etanólico de sapê foi de 38,8%, em relação ao controle (89,9%). O comprimento do hipocótilo, comprimento da raiz e número médio foliar de plântulas de rabanete foram 0,78 cm; 1,0 cm e 2,4 cm, respectivamente. Para alface os valores foram: 0,44 cm; 1,02 cm; 1,4 cm, respectivamente. A intensidade de inibição depende da concentração das substancias e seu tempo de contato. Pode-se afirmar que a planta de sapê possui propriedades químicas que podem ser usadas como controle biológico para plantas de folhas largas.
Process for the treatment of synthetic effluents. It consists of the biosorption process of dye and vegetable oil in a bioadhesive composed of a biomass whose properties reduce and regulate pH values of wastewater polluted with extreme pHs (strongly acid or strongly alkaline), oily contaminants and tincture. Can be used in powdered (powdered) form. To remove the color of the synthetic effluent from the manufacturing industry and products used in the staining of microbiology sheets in the laboratory.
The ability to monitor changes in biodiversity, and their societal impact, is critical to conserving species and managing ecosystems. While emerging technologies increase the breadth and reach of data acquisition, monitoring efforts are still spatially and temporally fragmented, and taxonomically biased. Appropriate long-term information remains therefore limited. The Group on Earth Observations Biodiversity Observation Network (GEO BON) aims to provide a general framework for biodiversity monitoring to support decision-makers. Here, we discuss the coordinated observing system adopted by GEO BON, and review challenges and advances in its implementation, focusing on two interconnected core components — the Essential Biodiversity Variables as a standard framework for biodiversity monitoring, and the Biodiversity Observation Networks that support harmonized observation systems — while highlighting their societal relevance.
Freshwater species are those species that would disappear if inland (non-marine) habitats, disappeared or were severely degraded. These habitats include rivers, streams, lakes, ponds, swamps, marshes, bogs, fens, and aquifers. Animals dependent on these habitats account for close to 10 % of all animal species. Hence they are a large part of biodiversity on earth and of most protected areas. However, determining what is a freshwater species is difficult for some species groups because of the large variation in the degrees and types of dependence of freshwaters within the group. Evidence on the effectiveness of actions that may help conserve freshwater species is growing rapidly. This evidence can help conserving freshwater species in protected areas but it needs to be integrated into a system-level-approach to species conservation which includes the identification of synergies and conflicts between freshwater species conservation and other management objectives for protected areas. Dependence on freshwater can make a species more vulnerable than similar marine or terrestrial species because freshwater habitats are often also sites of multiple and high levels of human activity. Partly for this reason, however, the mechanisms by which human activities impact upon freshwater species are often quite direct and easy to describe. This can lead to more community awareness about how their actions affect freshwater species. Hence it can also translate into greater support for the conservation of freshwater species. Steps towards integrating freshwater species in protected area management include: documenting freshwater species and ecosystems in the protected area; setting goals for freshwater biodiversity conservation; using conceptual models to explore how these goals relate to other management goals including the conservation of marine and terrestrial species and ecosystems; and efficiently implementing conservation actions that optimise multiple goals and benefits.
To be effective for freshwater biodiversity, conservation efforts must consider the particularities of these systems, such as the key role of spatial–temporal connectivity at maintaining ecological processes (e.g., periodic migrations or dispersal from refuge areas, gene flow, or transport of energy and matter essential for the persistence of populations and species) and the effective propagation of threats along these systems. New mechanisms are arising to encourage / support public and private funding to achieve improved outcomes for biodiversity conservation in freshwater systems (e.g. payments for ecosystem services, water reserves, biodiversity offsets and system-wide planning to limit the impacts of water infrastructure on aquatic ecosystems). Despite the increasing and innovative efforts to implementing conservation in freshwater systems in recent decades, there remains an urgent need for improved assessment of the effectiveness of freshwater protected areas through tailored monitoring programs. It will also be necessary to redouble efforts to ensure that freshwater protected areas are effectively implemented with appropriate management plans.
Detailed spatial information of changes in surface water extent is needed for water management and biodiversity conservation, particularly in drier parts of the globe where small, temporally-variant wetlands prevail. Although global surface water histories are now generated from 30 m Landsat data, for many locations they contain large temporal gaps particularly for longer periods (> 10 years) due to revisit intervals and cloud cover. Daily Moderate Resolution Imaging Spectrometer (MODIS) imagery has potential to fill such gaps, but its relatively coarse spatial resolution may not detect small water bodies, which can be of great ecological importance. To address this problem, this study proposes and tests options for estimating the surface water fraction from MODIS 16-day 500 m Bidirectional Reflectance Distribution Function (BRDF) corrected surface reflectance image composites. The spatial extent of two Landsat tiles over Spain were selected as test areas. We obtained a 500 m reference dataset on surface water fraction by spatially aggregating 30 m binary water masks obtained from the Landsat-derived C-version of Function of Mask (CFmask), which themselves were evaluated against high-resolution Google Earth imagery. Twelve regression tree models were developed with two approaches, Random Forest and Cubist, using spectral metrics derived from MODIS data and topographic parameters generated from a 30 m spatial resolution digital elevation model. Results showed that accuracies were higher when we included annual summary statistics of the spectral metrics as predictor variables. Models trained on a single Landsat tile were ineffective in mapping surface water in the other tile, but global models trained with environmental conditions from both tiles can provide accurate results for both study areas. We achieved the highest accuracy with Cubist global model (R 2 = 0.91, RMSE = 11.05%, MAE = 7.67%). Our method was not only effective for mapping permanent water fraction, but also in accurately capturing temporal fluctuations of surface water. Based on this good performance, we produced surface water fraction maps at 16-day interval for the 2000-2015 MODIS archive. Our approach is promising for monitoring surface water fraction at high frequency time intervals over much larger regions provided that training data are collected across the spatial domain for which the model will be applied.
Protected areas, although often terrestrially focused and less frequently designed to protect freshwater resources, can be extremely important for conserving freshwater biodiversity and supporting human water security necessary for people to survive and thrive. This study measured the quantity of water that is being provided by protected areas to areas downstream, and how threatened protected areas are in terms of their water provision. Building on a Freshwater Provision Index, the numbers of people who live downstream from these protected areas around the world were then assessed. The same process was applied to areas where there are no protected areas. Protected areas deliver 20% of the global total of approximately 40 000 km3 year−1 of continental runoff. More than one-quarter of water provisions supplied by the world's protected areas are exposed to low levels of threat and less than 10% are exposed to high levels of threat; this is compared with higher levels of threat for provisions from non-protected areas, where nearly one quarter of the provisions are exposed to high threat and only 10% are exposed to low threat. Nearly two-thirds of the global population is living downstream of the world's protected areas as potential users of freshwater provisions supplied by these areas. Despite the overall large volume of low-threat water supplied by protected areas, globally 80% of the downstream human community users receive water from upstream protected areas under high threat, and no continent has less than 59% of its downstream users receiving water from upstream protected areas under high threat. Globally, increased attention to reduce the threats to fresh water in areas under protection, as well as designation and management of additional areas, are needed to safeguard freshwater flows, and support biodiversity conservation and the provision of freshwater ecosystem services. Copyright © 2016 John Wiley & Sons, Ltd.
The Strategic Plan for Biodiversity (2011–2020), adopted at the 10th meeting of the Conference of the Parties to the Convention on Biological Diversity, sets 20 Aichi Biodiversity Targets to be met by 2020 to address biodiversity loss and ensure its sustainable and equitable use. Aichi Biodiversity Target 11 describes what an improved conservation network would look like for marine, terrestrial and inland water areas, including freshwater ecosystems. To date, there is no comprehensive assessment of what needs to be achieved to meet Target 11 for freshwater biodiversity. Reports on implementation often fail to consider explicitly freshwater ecosystem processes and habitats, the pressures upon them, and therefore the full range of requirements and actions needed to sustain them. Here the current progress and key gaps for meeting Aichi Target 11 are assessed by exploring the implications of each of its clauses for freshwater biodiversity. Concerted action on Aichi Biodiversity Target 11 for freshwater biodiversity by 2020 is required in a number of areas: a robust baseline is needed for each of the clauses described here at national and global scales; designation of new protected areas or expansion of existing protected areas to cover known areas of importance for biodiversity and ecosystem services, and a representative sample of biodiversity; use of Other Effective Area-Based Conservation Measures (OECMs) in places where designating a protected area is not appropriate; and promoting and implementing better management strategies for fresh water in protected areas that consider its inherent connectivity, contextual vulnerability, and required human and technical capacity. Considering the specific requirements of freshwater systems through Aichi Biodiversity Target 11 has long-term value to the Sustainable Development Goals discussions and global conservation policy agenda into the coming decades. Copyright © 2016 John Wiley & Sons, Ltd.
FWBON is a voluntary community of practice dedicated to tracking change in global biodiversity of inland waters FWBON currently has 136 Members from 52 countries. The membership profile is well matched to the current priorities and 2020 vision. However, Some major geographic gaps remain. FWBON is now ready to start working on: macroinvertebrate and fish sampling protocols; use of indigenous and local knowledge;and data mobilization. In the very near future we can start working on: sampling protocols for environmental DNA, algae, zooplankton, phytoplankton, fungi, periphyton; harmonized observations of reptiles, mammals, birds, amphibians; and harmonized protocols for ecoacoustic monitoring in freshwaters.
This chapter aims to assist biodiversity observation networks across the world in coordinating comprehensive freshwater biodiversity observations at national, regional or continental scales. We highlight special considerations for freshwater biodiversity and methods and tools available for monitoring. We also discuss options for storing, accessing, evaluating and reporting freshwater biodiversity data and for ensuring their use in making decisions about the conservation and sustainable management of freshwater biodiversity and provision of ecosystem services.