Assessment of trophic polymorphism in the Himalayan fish Tor putitora

An investigation into intra-specific morphological variation in Tor putitora fish from the Mahakali River in western Nepal was carried out. Three main hypotheses were tested: i) two distinct variants, one with thin lips and a forward-facing mouth (Type A), another with thick lips, an extended protrusion known as a mental lobe and more ventrally oriented mouth (Type B), can be distinguished by meristic, allometric or landmark-based morphometric analyses; ii) differences in ecological conditions in spatially separated breeding streams, potentially linked to environmentally influenced morphological variation, can be observed; iii) differences in stable isotope ratios of carbon and nitrogen obtained from fish scales, and therefore evidence of dietary divergence, are evident between the two morphotypes. Meristic and allometric analyses provided no evidence of distinguishing features between the morphotypes, however the landmark-based morphometric analysis produced very strong evidence that the two morphotypes clearly differ in shape and features of the head and mouthparts. Analysis of the physico-chemical conditions and aquatic invertebrate communities in the spatially separated breeding streams produced results which refuted the second hypothesis but suggested strongly that differences between seasons (snow-melt and post-monsoon) were statistically significant and suggested an alternative hypothesis that breeding events may be segregated temporally, rather than spatially. Stable isotope analysis uncovered statistically significant differences in nitrogen isotope ratios which supported the hypothesis that the two morphotypes display divergence in diet, very likely linked to the morphological variation in the head and mouthparts. This examination provides evidence of trophic polymorphism in T. putitora and illuminates the path to further studies of this phenomenon which has been observed in several other species of the same genus across south and southeast Asia

Fish assemblage change following the structural restoration of a degraded stream

Decades of anthropogenic pressure have harmed riverscapes throughout North America by degrading habitats and water quality and can result in the extirpation of sensitive aquatic taxa. Local stream restoration projects have increased in frequency, but monitoring is still infrequent. In 2010, Kickapoo Creek in East Central Illinois was subjected to a stream restoration project that included implementation of artificial riffles, riprap, scouring keys, and riparian vegetation. We monitored the restoration efforts for 6years after the restoration through annual sampling efforts at restored and reference sites to determine changes in habitat and fish assemblage using standard habitat sampling and electrofishing techniques. We observed distinct temporal and spatial shifts in physico-chemical parameters along with changes in fish community structure. Although biotic integrity remained moderately low in reference assemblages, restored reaches showed 3-year delay in response to restoration, with biotic integrity positively linked to additional instream habitat and altered channel morphology. Larger substrate sizes, submerged terrestrial vegetation, and newly formed scour pools along with reduced siltation were found in the restored sites, in contrast to the reference sites. These changes resulted in increased species diversity, reduced number of opportunistic species and consequently an overall increase in health of fish communities. We also observed recruitment of habitat specialists and increase in species with reproductive strategies that rely on complex substrates. The results of this study highlight some of the complex dynamics driving reach-scale restoration projects. We demonstrate the usefulness of structural restoration as a management tool to increase biotic integrity through long-term alteration of critical habitat. The delay in the response of species to the restoration efforts emphasizes the need for long-term continuous temporal and spatial monitoring

A baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change

This report forms part of a larger research programme on 'Reinterpreting the Urban-Rural Continuum', which conceptualises and investigates current knowledge and research gaps concerning 'the role that ecosystems services play in the livelihoods of the poor in regions undergoing rapid change'. The report aims to conduct a baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. The appraisal is conducted at three spatial scales: global, regional (four consortia areas), and meso scale (case studies within the four regions). At all three scales of analysis water resources form the interweaving theme because water provides a vital provisioning service for people, supports all other ecosystem processes and because water resources are forecast to be severely affected under climate change scenarios. This report, combined with an Endnote library of over 1100 scientific papers, provides an annotated bibliography of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. After an introductory, section, Section 2 of the report defines water-related ecosystem services and how these are affected by human activities. Current knowledge and research gaps are then explored in relation to global scale climate and related hydrological changes (e.g. floods, droughts, flow regimes) (section 3). The report then discusses the impacts of climate changes on the ESPA regions, emphasising potential responses of biomes to the combined effects of climate change and human activities (particularly land use and management), and how these effects coupled with water store and flow regime manipulation by humans may affect the functioning of catchments and their ecosystem services (section 4). Finally, at the meso-scale, case studies are presented from within the ESPA regions to illustrate the close coupling of human activities and catchment performance in the context of environmental change (section 5). At the end of each section, research needs are identified and justified. These research needs are then amalgamated in section 6

Monitoring and assessment of macroinvertebrate communities in support of river management in northern Vietnam

The thesis aimed to develop a water quality biological monitoring and assessment based on macro-invertebrates to analyse the status of watercourses and to select sustainable restoration measures in order to support river. The research was carried in the Du river basin in northern Vietnam. Spatial and temporal analysis showed that macro-invertebrate community compositions in the Du river were not only driven by morphological characteristics but also by water quality issues. A relatively small temporal variation was detected that requires no remarkable modifications in the development of a bio-assessment methodology for watercourses in the specific river. Multivariate analyses using CCA and Bray-Curtis cluster analysis provided a similar discrimination between pristine and impacted sites in the Du river basin. Qualitative biotic indices including the BMWP-Viet proved to be appropriate for use in the studied watercourses in Vietnam. The BMWP-Viet could differentiate study sites into classes ranging from very good to very poor ecological conditions. The current BMWP-Viet approach can be useful at an early stage of bio-assessment application in Vietnam. However, this method should be improved by optimising the scoring system for common taxa and development of more robust assessment approaches such as multi-metric indices. Data mining techniques including classification trees and support vector machines were applied to develop predictive models for BMWP-Viet as well as presence/absence of macro-invertebrate taxa (ecological indicators). Optimised models indicate the major environmental variables influencing the presence/absence of macro-invertebrates, which in the mean time also reflect the river characteristics that river managers have to consider in their policy plans. A decision support system, the WFD-Explorer was combined with classification trees to link human activities with the ecological river conditions and analyse the relevance of several restoration options

Treatment of Perfluorinated Compounds and Nitroaromatics by Photocatalysis in the Presence of Ultraviolet and Solar Light

Nitroaromatic compounds (NACs) and perfluorinated compounds (PFCs) are two classes of water contaminants of DoD concern due to their risk to the environment, personnel, and mission. This study investigated the potential of an innovative technology, oxidation using titanium dioxide (TiO2) and TiO2 doped with silver (Ag-TiO2) as photocatalyst, to effectively and energy efficiently treat NAC and PFC-contaminated water. Three model contaminants, 2,4-DNT (NAC), and PFOA and PFOS (PFCs), were degraded using TiO2 and Ag-TiO2 immobilized on glass slides under sunlight and UV light in atmospheric conditions and at neutral pH. 2,4-DNT degraded 14% and 15% in the presence of Ag-TiO2 and TiO2, respectively, under sunlight after 8 hours. After 8 hours under UV light, 2,4-DNT degraded 13% and 29% in the presence of Ag-TiO2 and TiO2, respectively. Results indicate that PFOA and PFOS do not degrade under the conditions of the experiment. Further study is needed to investigate the viability of the technology to treat NAC- and PFC-contaminated water

Analyzing of Morphometric Parameters and Designing of Thematic Maps Using Raster Geoprocessing Tool

GIS techniques, digital elevation models (DEM), raster geoprocessing tools, and software such as ArcMap are a quick and simultaneous solution for the assessment, measurement, and analysis of morphometric parameters of river basins. This paper aims to show the use of the Digital Elevation Model and the ArcGIS program for the analysis of morphometric parameters and the construction of a set of thematic maps needed for spatial planning, water resources management, and similar purposes. Through these techniques, 18 morphometric parameters were determined and analyzed in the study area, which is located in the central part of the Republic of Kosovo and covers an area of 38 km2, and 15 thematic maps were constructed. The altitude of the area varies from 544 m to 1019 m, the slope from 24%, with a total number of stream segments of 601 and a drainage density of 5.02 km/km2. The analysis of morphometric parameters presents an important indicator regarding the space and other elements of the river basin. Doi: 10.28991/CEJ-2022-08-09-06 Full Text: PD

Understanding mountain soils : a contribution from mountain areas to the International Year of Soils 2015

Smallholder farmers in the Taita hills and Mount Kilimanjaro recognize the need to conserve soil nutrients of fields and farms located in the upper, middle and lower zones of mountainous areas. These mountain communities depend on rain-fed subsistence agriculture which means that for sustainable subsistence crop production, they also depend on nutrient availability and use efficiency in farming households. A study under way in the area has looked at loss of land cover and infestations of plant pests and diseases and is using this information to raise farmers’ awareness of soil fertility and to introduce best cropping practices

A multi-disciplinary approach to the characterization of waterlogged burial environments : assessing the potential for the in situ preservation of organic archaeological remains

The aim of this study was to characterise waterlogged burial environments and to assess their potential for the in situ preservation of organic archaeological remains. To characterise these environments, environmental parameters were monitored through the soil profile and integrated with a study of the composition and activity of the microbial community.Soil cores were taken from two wetland sites located in the Humberhead Levels in Yorkshire: Hatfield Moor and Sutton Common. Cores were subsampled at depth intervals down to 100 cm depth, to allow for the examination of the vertical distributions of the variables being studied. Redox potential, water level variation and other physico-chemical parameters were measured down the soil profile. Bacterial abundance was determined by direct counts; activity was assayed by extracellular enzyme activity and leucine assimilation. The physiological profile of the microbial community was analysed using BIOLOG and the bacterial community structure was examined by PCR-DGGE.Redox potential readings were positive above the water table and negative below. The bacterial abundance and activity were greatest at the soil surface and, in general, decreased with depth. BIOLOG showed both depth variation and between site variation in microbial physiological profile. DGGE gels presented a different bacterial community structure with depth and between-sites.The results from monitoring of redox potential combined with water table height and determination of bacterial abundance and activity allowed the recognition of stratigraphic horizon where there was less potential for microbial degradation of organic archaeological artefacts. The information from BIOLOG and DGGE holds the potential for the development of a more subtle understanding of between-depth and between-site differences in the degradation process.The physico-chemical and the conventional and molecular microbiological results presented in this thesis have shown that microbial activity is implicated as a key factor that could lead to compromised in situ preservation conditions at the sites studied