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Reply to Global high-altitude limits for amphibians by Tracie A. Seimon and Anton Seimon (2015)
Get PDFHigh altitude records of amphibians in the age of Climate Change With the problem of global warming looming large on our planet the existence of many species are under threat. Researchers are racing to bring in new information on the impact of climate change on global biodiversity (Walther et al. 2002; Parmesan & Yohe 2003; Campbell et al. 2009; Xu et al. 2009; Bellard et al. 2012; Gottfried et al. 2012; Shrestha et al. 2012). There have been a large number of studies that have documented range shifts of species due to climate change (Walther et al. 2005; Araujo & Rahbek 2006; Hickling et al. 2006; Chen et al. 2011). The new records on altitude of both flora and fauna as a result of range extension due to climate change have become quite frequent. In this context, we agree with Seimon et al. (2015) who have neatly summarized the three problems on new findings about altitude records in their Response to our paper (Subba et al. 2015). Furthermore, we agree with authors that often vital data may be hidden within other larger issues; as a result missing out on relevant data seems to be a reoccurring problem (Seimon et al. 2007a). In this age of easy access to information and an era where scientists and citizens are coming together to bridge the gap in information, there is a need to make the data easily available and visible. New records should also be followed by the exact location (latitude - longitude) where the species was observed or collected along with the stage of development
Water: a quintessential public good that needs public solutions
Get PDFBring up the topic of water, and you are bound to get everybody’s attention and probably a heated discussion going. Water is a part of our lives in so many different ways: not just for survival activities of drinking or cooking, but also in the production of our food, in many industrial activities, and even as a carrier of our waste. And in India, as in many other densely populated and rapidly industrialising sub-tropical regions, water
scarcity, water pollution and too much water (flooding) are all major societal challenges. Responding to these challenges properly requires understanding how water is the quintessential environmental public good, and what kind of public actions may be required
Biocontrol Potential of Metarhizium anisopliae (Metsch.) Sorokin (Deuteromycotina: Hyphomycetes) against Ailanthus Defoliator, Eligma narcissus (Cram.)
No full textEligma narcissus is recognised as a serious pest of Ailanthus in Southern India and defoliation of Ailanthus by this pest causes apparent loss of growth increment. The common control methods for this pest is mostly insecticides and the concern about the environmental effects of chemical insecticides, has emphasised the use of environmentally more benign microbial agents. Among entomopathogens, Fungi are the most explored and often act as important natural control agents that limit insect populations. On this point of view, Bio efficacy of 25 isolates of Metarhizium anisopliae was assessed to establish their virulence against E. narcissus in the laboratory and effective formulations of two potent isolates were subsequently evaluated in the field. MIS7 and MIS13 were more effective among the different isolates evaluated against E. narcissus. The median lethal concentration (LC50) of all the isolates ranged from 6.46×105 conidia/ml to 628.92×105 conidia/ml. Median lethal concentration of (LT50) of 4.9 and 5.4 days were recorded for MIS7 and MIS13 respectively at a concentration of 1× 107 conidia/ml. Virulence tests of the isolates MIS7 and MIS13 and 0.5% Pongamia pinnata seed oil, individually and in different combinations, indicated improved efficacy of the isolates when used in combination and also when combined with seed oil. Formulations composed of “MIS7+MIS13+0.5% Pongamia pinnata seed oil” and “MIS7+MIS13” proved to be superior against E. narcissus, causing 76.30% and 93.93% mortality, respectively. Field evaluation of the formulation MIS7+MIS13+0.5% Pongamia pinnata seed oil recorded 5.79 larvae per plant resulting in 60.53% reduction of infestation while the formulation, MIS7+MIS13 showed 53.76% reduction of infestation with 6.56 larvae per plant. The observations from this study suggest the prospects of using the entomopathogenic fungus, M. anisopliae for the control of E. narcissus
Contribution of sewage treatment to pollution abatement of urban streams
Get PDFIn this study, we assessed the efficiency and effectiveness
of the Vrishabhavathy Valley Treatment plant (VVTP) in Bengaluru city, which is the oldest STP in the city. Since VVTP treats both raw sewage and polluted river water, with the latter constituting 80% of the influent, we sampled water quality at locations upstream and downstream of the plant to evaluate overall efficacy as well
The social distribution of provisioning forest ecosystem services: Evidence and insights from Odisha,India
No full textEcosystem services research has highlighted the importance of ecosystems for human well-being. Most of the research, however, focuses only on aggregate human well-being and disregards distributional and equity issues associated with ecosystem services. We review approaches from institutional economics, political ecology and the social sciences in order to develop an analytical framework to understand the distribution of benefits from ecosystems across different socio-cultural groups and the underlying social processes involved. We then present a case study of the distribution of provisioning ecosystem services in a forest-fringe village in Odisha, India. Our analysis shows the unequal distribution of ecosystem services and complex social processes that determine these. We identify the determining factors and processes to include: differential resource-specific needs, different cultural identities, differentiated social status and bargaining power, exclusionary and inclusionary social practices, differential access. Our analysis proves therefore that aggregation of forest ecosystem benefits obscures crucially important patterns of distribution, and the underlying social processes that determine these. This also demonstrates the necessity of applying social science frameworks in such analyses. Our study also shows that most ecosystem services are co-produced through both ecosystem processes and social actions, and so their assessment cannot be separated from the social context in which they are embedded. In conclusion we recommend that ecosystem services research engages more with process-oriented, context-specific and integrated approaches, based on a recognition of the complexity of social ecological realities
Reimagining the past – use of counterfactual trajectories in socio-hydrological modelling: the case of Chennai, India
Get PDFThe developing world is rapidly urbanizing. One of the challenges associated with this growth will be to supply water to growing cities of the developing world. Traditional planning tools fare poorly over 30–50 year time horizons because these systems are changing so rapidly. Models that hold land use, economic patterns, governance systems or technology static over a long planning horizon could result in inaccurate predictions leading to sub-optimal or paradoxical outcomes. Most models fail to account for adaptive responses by humans that in turn influence water resource availability, resulting in coevolution of the human–water system. Is a
particular trajectory inevitable given a city’s natural resource endowment, is the trajectory purely driven by policy or are there tipping points in the evolution of a city’s growth that shift it from one trajectory onto another
Determinants of household use of wetland resources in West Bengal, India
No full textThis paper makes an attempt to identify and analyse the factors that influence the household use of wetlands in West Bengal, India. Three wetlands were selected from three physiographically distinct regions of West Bengal, which are used by local people for multiple purposes. Logit and Tobit models are used for the identification of the factors explaining household dependency on wetland. The results indicate that there is spatial difference in the mode and extent of use of wetland resources across the three wetlands. Households belonging to poor, landless, lower social caste, and low education level are more likely to use wetland resources compared to their
counterparts. Households having larger family size are
likely to extract bigger amounts of wetland products.
However, upper caste households have more access to the wetlands for irrigation. The results indicate that wetland plays a vital role for the livelihood of marginalized sections of the community. Therefore,
it is needed to device appropriate policy for equitable
distribution of the benefits of the wetlands among
different sections of the society
Topographic and Bioclimatic Determinants of the Occurrence of Forest and Grassland in Tropical Montane Forest-Grassland Mosaics of the Western Ghats, India
Get PDFThe objective of this analysis was to identify topographic and bioclimatic factors that predict occurrence of forest and grassland patches within tropical montane forest-grassland mosaics. We further investigated whether interactions between topography and bioclimate are important in determining vegetation pattern, and assessed the role of spatial scale in determining the relative importance of specific topographic features. Finally, we assessed the role of elevation in determining the relative importance of diverse explanatory factors. The
study area consists of the central and southern regions of the Western Ghats of Southern India, a global biodiversity hotspot. Random forests were used to assess prediction accuracy and predictor importance. Conditional inference classification trees were used to interpret
predictor effects and examine potential interactions between predictors. GLMs were used to confirm predictor importance and assess the strength of interaction terms. Overall, topographic and bioclimatic predictors classified vegetation pattern with approximately 70%
accuracy. Prediction accuracy was higher for grassland than forest, and for mosaics at higher elevations. Elevation was the most important predictor, with mosaics above 2000m dominated largely by grassland. Relative topographic position measured at a local scale
(within a 300m neighbourhood) was another important predictor of vegetation pattern. In high elevation mosaics, northness and concave land surface curvature were important predictors of forest occurrence. Important bioclimatic predictors were: dry quarter precipitation,
annual temperature range and the interaction between the two. The results indicate complex interactions between topography and bioclimate and among topographic variables. Elevation and topography have a strong influence on vegetation pattern in these mosaics.
There were marked regional differences in the roles of various topographic and bioclimatic predictors across the range of study mosaics, indicating that the same pattern of grass and forest seems to be generated by different sets of mechanisms across the region, depending on spatial scale and elevation
Functionality of wildlife corridors in the fragmented landscape of the Western Ghats, India: Implications for conservation and management
Get PDFMost of the wildlife and their habitats are extremely threatened due to increasing demands on forest land and forest resources. Urbanization, expanding human habitations, encroachment of forest land, expansion of farming area, unsustainable forest resource extraction etc increase pressure and associated impacts on the forest and wild animals. Dams, mining and linear intrusions such as roads in protected areas (PAs) and in the fringes either reduce, degrade or fragment wildlife habitat leading to disruption of genetic exchanges amongst wildlife populations. According to meta-population, meta-community and island-biogeography theories, fragmentation of natural habitats could lead to extinction of many species across the globe due to loss of sub-population connectedness and inbreeding depression.
Mammals with large home range such as elephant, tiger and leopard etc., are the most affected as habitat degradation that reduces foraging and breeding area, vulnerable to extinction from the loss of subpopulation connectedness, reduced dispersal capacity as well as lower population viability. Globally 20% of known mammal species are currently listed as under threat and are more prone to extinction due to large body size, low reproductive potential (long gestation periods and late weaning ages), large home range, higher individual energy requirement, lower population density, vulnerability to reserve edge effects and anthropogenic threats.
As a spin-off, fragmentation and degradation of wildlife corridors lead to frequent human-wildlife conflict (HWC), especially in the case of large migratory wild herbivores and wide ranging carnivores. Encapsulated populations of large home ranging animals like elephants in a matrix of fragmented forests surrounded by dense human population have to move between forests in search of water, forage and shade. During the process of animal movement, farmlands along or across the animal’s migratory routes and also the adjacent areas experience high incidences of crop raiding or other types of HWC. Retaliatory killing of animals, destructive activities on wildlife habitats by the affected community, poaching, negative perceptions towards wildlife conservation are the major outcomes due to HWC. Also, HWC could undermine the relationship between Forest Management and local people, impeding conservation efforts regionally.
In fragmented landscape, improving the functional status of wildlife corridors and structural connectivity could reinstate an array of ecological and environmental benefits; such as resources including animal food plants, herbals, Non-Timber Forest Products (NTFP) and fuelwood. Third chapter is about assessing habitat quality of the forest-corridor landscape with reference to vegetation structure that is impacted by Lantana camara invasion, fuel wood collection and cattle grazing. Transect method has been used to quantitatively characterize the forest-corridor landscape. Overall density of tree, shrub and herb was relatively high in corridor area (CA) and corridors compared to non-corridor area (NCA). The grass cover was more in NCA than CA and corridors. Fuelwood collection and livestock grazing coupled with invasive species Lantana camara have shaped the present vegetation structure in the corridor landscape. I have identified composition and size of the regional plant species pool for restoration. Large scale Lantana camara removal coupled with enrichment planting activity as part of restoration needs be initiated in the degraded corridors to improve the habitat quality
Reproductive assurance through autogamous self-pollination across diverse sexual and breeding systems
Get PDFPollination becomes a constraint when conspecific plants and/or their pollinators become scarce. Many plant species have evolved autogamous self-pollination as a means of reproductive assurance (RA) under pollination-uncertain environments. So far RA has been studied and discussed largely with reference to self-compatible species producing bisexual flowers. RA seems to have evolved across all other sexual and breeding systems - monoecy, dioecy and self-incompatibility (SI). Both monoecy and dioecy produce bisexual flowers (andro/gyno-monoecy, andro/gynodioecy and polygamous conditions) which may provide RA. Similarly, most of the SI species are leaky and do set some seeds upon self-pollination. This phenomenon termed 'partial self-compatibility' is quite common and does provide RA in SI species. Although dioecy and SI have evolved as obligate outbreeding systems, they seem to have reached an evolutionary dead end because of the constraints for outcross pollination. In the light of habitat destruction leading to a reduction in the diversity and density of native pollinators, it is likely that many of the obligate outbreeders tend to shift to mixed mating system in the coming decades. Similarly, obligate mutualism in which each plant species is dependent on one animal species for pollination also seems to have reached a dead end and the trend is to abandon such obligate mutualism as a survival strategy. In the absence of such a change, obligate out breeders and those with highly specialized pollination system are likely to become endangered or even extinct