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Shah R.D.T.,Hindu Kush Himalayan Benthological Society | Shah D.N.,Senckenberg Institute
Ecological Indicators | Year: 2012

Biotic indices based on benthic macroinvertebrates are increasingly being used to assess the ecological quality of running water worldwide. In Nepal in the central Himalaya, five biotic indices have been developed in succession over the last decade to assess the ecological status of rivers, namely: the NEPbios, BRSbios, GRSbios, HKHbios, and NEPbios-Extended. The implementation of control and protection policies should be based on indices with proven reliability. Such reliability refers to the ability of the index to detect the correct status about the health of the assessed environment. So in the present study, we compare the performance of these five indices to determine the most robust, reliable biotic index for Nepal. In total, 248 biological samples belonging to first- to sixth-order streams were analyzed. Each sampling site was preclassified in situ using a screening protocol and later validated with physicochemical parameters to reflect the actual field condition. Overall, the GRSbios proved to be the most reliable, followed by the NEPbios-Extended, HKHbios, NEPbios, and BRSbios. The results were further validated by the ROC (Receiver Operating Characteristic) curve method. The study recommends applying the GRSbios to ecologically assess rivers in Nepal. In addition, we discuss modifying the GRSbios method to consider the future impacts of global change. © 2012 Elsevier Ltd. All rights reserved. Source


Busse S.,University of Gottingen | von Grumbkow P.,University of Gottingen | Hummel S.,University of Gottingen | Shah D.N.,Senckenberg Research Institutes and Natural History Museums | And 5 more authors.
PLoS ONE | Year: 2012

Unusual biogeographic patterns of closely related groups reflect events in the past, and molecular analyses can help to elucidate these events. While ample research on the origin of disjunct distributions of different organism groups in the Western Paleartic has been conducted, such studies are rare for Eastern Palearctic organisms. In this paper we present a phylogeographic analysis of the disjunct distribution pattern of the extant species of the strongly cool-adapted Epiophlebia dragonflies from Asia. We investigated sequences of the usually more conserved 18 S rDNA and 28 S rDNA genes and the more variable sequences of ITS1, ITS2 and CO2 of all three currently recognised Epiophlebia species and of a sample of other odonatan species. In all genes investigated the degrees of similarity between species of Epiophlebia are very high and resemble those otherwise found between different populations of the same species in Odonata. This indicates that substantial gene transfer between these populations occurred in the comparatively recent past. Our analyses imply a wide distribution of the ancestor of extant Epiophlebia in Southeast Asia during the last ice age, when suitable habitats were more common. During the following warming phase, its range contracted, resulting in the current disjunct distribution. Given the strong sensitivity of these species to climatic parameters, the current trend to increasing global temperatures will further reduce acceptable habitats and seriously threaten the existences of these last representatives of an ancient group of Odonata. © 2012 Büsse et al. Source


Shaha R.D.T.,Hindu Kush Himalayan Benthological Society | Shaha R.D.T.,Senckenberg Institute | Shahb D.N.,Senckenberg Institute | Shahb D.N.,Biodiversity and Climate Research Center | And 2 more authors.
International Journal of Odonatology | Year: 2012

Although understanding of geographic range shifts of many species in response to global climate change is expanding steadily, little is known about the Himalayan fauna, which in particular is affected by relatively faster warming rates than other parts of the world. Anticipated increases in temperature and changes in hydrological regimes will have significant adverse impacts on the habitat suitability for many species. This threat will even be higher to endemic and already threatened species due to their restricted distribution and narrow climate tolerance ranges. We investigated the range shifts of a relict Himalayan dragonfly (Epiophlebia laidlawi), a species that is endemic to the Hindu Kush Himalayan region. Currently, the species is only known from few localities in Bhutan, India and Nepal. For conservation of the species, it is necessary to foresee potential suitable habitat areas and range shifts due to global climate change. Here, we first estimated the current potential geographic distribution by identifying the suitable habitat area in the region using bioclimatic envelope models, by means of consensus projections of six algorithms as implemented in the BIOMOD-package in the software program R. We then used the current distribution to render future projections under the A2a and B2a IPCC emission scenarios for the years 2050 and 2080. Models predict that the suitable habitat area of the species will shift on average 374m and 599m uphill under the extreme (A2a) climate warming scenario, and 294m and 342m uphill under the moderate (B2a) scenario by 2050 and 2080, respectively. Future suitable habitat areas are projected to remain only in the high mountains of eastern Nepal. The results will help conservationists to delineate priority habitats in the first step towards the species conservation in the region. © 2012 Worldwide Dragonfly Association. Source


Nesemann H.,Central University of Bihar | Tachamo Shah R.D.,Hindu Kush Himalayan Benthological Society | Shah D.N.,Hindu Kush Himalayan Benthological Society | Sharma S.,Kathmandu University
Odonatologica | Year: 2011

Based on 78 specimens recorded from 14 forest streams at the elevations between 1800 and 2850 m a.s.1. in central Nepal, 9 larval instars are described and illustrated. E. laidlawi is for the first time documented from the Sim and Indrawati watersheds. The habitats are described and clearly indicated that the sp. is widespread but has a restricted range. The protection of the habitats is essential for its conservation. Source


Shah R.D.T.,Hindu Kush Himalayan Benthological Society | Shah D.N.,Hindu Kush Himalayan Benthological Society | Nesemann H.,Bornstrasse 73
International Journal of Hydrology Science and Technology | Year: 2011

In Nepal, the impairment status of lakes and reservoirs has generally been measured and classified based on nutrient concentrations and physico-chemical parameters, typically with no direct measurement of biological communities. In response to the recent focus on the bioassessment of lakes and reservoirs, the macroinvertebrate-based Nepal Lake Biotic Index (NLBI) has been developed. Benthic samples were collected from reference and impaired lakes during 2006 and 2009 from two ecological zones: Terai-Siwaliks and Mid-Hills. We used a tolerance score based on a ten-point scoring system ranging from very pollution sensitive to very pollution tolerant taxa to calculate the NLBI. In reference to the transformation scale, the calculated NLBI describes the lake water quality as high, good, fair, poor and bad. Candidate metrics of richness measures and tolerance measures discriminated well between the reference and impaired lakes (Mann-Whitney U test, p < 0.01). The relationships between the biological metrics and the environmental variables were also established with the lake water quality class (LWQC). Further, the validation of the NLBI performance was done by assessing nine lakes/reservoirs from both the zones. Thus, the index presented here provides an effective method to measure the ecological condition of lakes and reservoirs in Nepal. Copyright © 2012 Inderscience Enterprises Ltd. Source

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