A5054087126- Diatoms and Algae Research
- Freshwater macroinvertebrate diversity and ecology
- Aquatic Invertebrate Ecology and Behavior
- Aquatic Ecosystems and Phytoplankton Dynamics
- Environmental Toxicology and Ecotoxicology
- Fish Ecology and Management Studies
- Pharmaceutical and Antibiotic Environmental Impacts
- Marine and coastal ecosystems
- Effects and risks of endocrine disrupting chemicals
- Water Quality and Pollution Assessment
- Microbial Community Ecology and Physiology
- Fish biology, ecology, and behavior
- Protist diversity and phylogeny
- Geology and Paleoclimatology Research
- Lichen and fungal ecology
- Isotope Analysis in Ecology
- Pesticide and Herbicide Environmental Studies
- Toxic Organic Pollutants Impact
- Groundwater and Isotope Geochemistry
- Microplastics and Plastic Pollution
- Genomics and Phylogenetic Studies
- Analytical chemistry methods development
- Soil and Water Nutrient Dynamics
- Methane Hydrates and Related Phenomena
- Microbial bioremediation and biosurfactants
National Museum Wales
2013-2024
Luxembourg Institute of Science and Technology
2023
Cardiff University
1997-2013
Institute of Groundwater Ecology
1998-2004
Natural History Museum
2000-2003
Technische Universität Berlin
2000
University of Wales
1996
Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT
1996
Springs are unique aquatic habitats that contribute significantly to local and regional biodiversity because of their high habitat complexity the large number different spring types. Many springs small, but they numerous often water quality, thus, provide for species rare elsewhere sensitivity anthropogenic impacts (least-impaired relicts). species-rich contain a larger Red List taxa than other habitats. Hydrological factors, particularly flow permanence, chemistry, temperature important...
SUMMARY 1. Surprisingly few data compare the apparent responses of diatoms and macroinvertebrates to metals in streams. We examined variation metals, between 51 streams metal‐mining areas Wales Cornwall, U.K., using a survey design with multiple reference polluted sites. 2. To quantify variations sites, we calculated cumulative criterion unit (CCU) scores, recently defined measure total stream metal concentration toxicity, account for additive effects each relative putative toxic thresholds....
SUMMARY 1. Hydrobiological changes were assessed along an altirudinal transect of eighteen to twenty‐three tributaries from 600 3750m in two adjacent river systems east‐central Nepal. The incorporated catchments under terraced agriculture at the lowest altitudes Likhu Khola, through streams forest, alpine scrub and tundra higher Langtang. 2. Diatoms, bryophytes, macroinvertebrates fish all showed pronounced altitudinal assemblage composition as shown by TWINSPAN DECORANA. A few taxa...
Summary 1. Diatoms are recognised as indicators in temperate streams, but only recently have assessments begun of their value indicating stream quality the tropics and sub‐tropics. Here, we extend previous studies by assessing diatom assemblages relation to water habitat character Kathmandu Valley, Middle Hills Nepal northern India. We also assessed whether U.K. Trophic Diatom Index (TDI) was sufficiently portable reveal pollution Himalayan rivers. In more urbanised highly agricultural...
1. Using a replicated survey design at the catchment scale, we compared composition and diversity of diatom communities in three stream groups Middle Hills Nepal: semi‐natural reference (Arun Valley), enriched by agricultural runoff (Likhu Khola) grossly polluted sewage (Kathmandu Valley). We sampled riffles all sites; Kathmandu Valley Likhu Khola also diatoms pools on vegetation. 2. Species richness H′ were significantly higher streams than either organically or references. Community...
Two new taxa similar to Achnanthidium minutissimum were common and abundant in samples collected during a survey of benthic diatoms watercourses from mainland Portugal. They are described here as A. duriense, sp. nov. lusitanicum, In addition, the recently pseudolineare is reported various localities its ecology detail. The species Portugal compared with type material morphologically taxa: microcephalum, Achnanthes minutissima, minutissima var. cryptocephala, inconspicua nana. analysis this...
Abstract High altitude ecosystems have important natural ecological functions but are under increasing impacts from human activities and climate change. A detailed analysis of the water chemistry Lake Rara, a high mountain lake in western Nepal, was carried out October 2015 April 2016. total 31 samples were collected. Major ions (Ca 2+ , Mg Na + K SO 4 2− NO 3 − Cl ) analysed by ion chromatography. Si PO 3− following standard protocols. Conductivity, pH, dissolved solids (TDS), turbidity...
During a survey of the diatom flora Adegoy River (Krasnodar Territory, Russia), an unknown Fragilaria species (Bacillariophyta) was found that could not be identified using currently available literature and here we describe it as new species. The morphology irregularis sp. nov. studied light scanning electron microscopy compared to similar including deformis, F. rinoi, septentrionalis Fragilariforma bicapitata. It differed from these taxa in several characters. Most observed valves showed...
Interpreting long-term variability in mountain stream ecosystems is challenging where potential causes such as climate change and altered land-use act simultaneously. The scarcity of historical data also limits research opportunity, especially at low latitudes. Here we assess the macroinvertebrate fauna 12 Himalayan streams Nepal covering an altitudinal gradient from 1500 to 3900 m asl using 1992, 2022 2023. We aimed to: 1) compare richness community composition over three decades short-term...
Variations in diatom communities between river habitats might have ramifications for their use as bioindicators and the assessment of contribution to aquatic biodiversity. Diatoms therefore were sampled from similar surface areas epilithon bryophytes 24 hill-streams Nepalese Himalaya assess whether varied more strongly or streams. Some species (e.g. Eunotia minor Coccaneis placentula) significantly abundant on than epilithon. In addition, held, average, a larger proportion total pool diatoms...
Summary 1. Acid‐base status has major effects on diatoms, but there is little information their short‐term response to changing acidity. This despite the use of diatoms as bioindicators in streams where acid episodes are important during rainstorms (hours days) or snowmelt (days weeks). In Llyn Brianne experimental catchments (Wales, UK), we attempted mimic acidification by (i) reciprocally transplanting between two contrasting acidity and (ii) using acid‐diffusing substrates. 2. Diatom...
Jüttner I., Krammer K., Van de Vijver B., Tuji A., Simkhada Gurung S., Sharma C. and Cox E.J. 2010. Oricymba (Cymbellales, Bacillariophyceae), a new cymbelloid genus three species from the Nepalese Himalaya. Phycologia 49: 407–423. DOI: 10.2216/09-77.1A is described with its type based on Cymbella japonica Reichelt. In addition, are Himalaya: O. subaequalis, latirotundata subovalis. The has slightly dorsiventral or almost symmetrical valves polar raphe endings deflected to dorsal side. It...
Abstract We investigated the effect of 4-nonylphenol (NP) on nematode communities in sediment freshwater microcosms. Seven treatments were dosed with various concentrations NP over a period six weeks by using controlled-release method (NP1-NP7; maximum concentrations: 0.29–3.37 mg/kg dry wt). Four microcosms not exposed to and served as controls. Nematode analyzed 15 weeks, including sampling dates before, within, after application. Communities characterized terms total abundance species...
Gomphonema parvulum Kützing and morphologically similar species can be difficult to distinguish while differing markedly in their ecology. It is important identify these correctly if the ecological status of habitats assessed accurately. Here, two this group are documented using light scanning electron microscopy. The type material G. exilissimum (Grunow) Lange-Bertalot & E. Reichardt Van Heurck Collection, Meise, was examined, as well recently collected populations from Scotland Sweden. A...
Despite concerns about the toxicity of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), there are still few data on their past trends in Middle Europe. Here, we use paleolimnology to assess occurrence PCDD/F sediments four remote Black Forest lakes where atmospheric deposition has been only possible input. Considerable quantities occurred sedi ments one lake before production chlorophenols 1920s, emphasizing that they not recent contaminants. On basis homologue profiles typical...