Removal of fluoride from water by using a coagulant (inorganic polymeric coagulant)

Environmental Science and Pollution Research - Excess fluoride (F) ion of drinking water is a major problem in many areas of India and causes harmful effects such as dental and skeletal fluorosis....     

Selection of suitable lichen bioindicator species for monitoring climatic variability in the Himalaya

Interspecific comparison in metals and PAHs profile in three lichen species, Flavoparmelia caperata, Phaeophyscia hispidula and Pyxine sorediata, were studied in different altitudinal gradients of the Western Himalayas. The species collected from 14 sites, enroute from Dehradun to Morinda (243 Km) including the trekking route 42 Km from Taluka to Morinda having an altitudinal gradient between 850–3,750 m, were analysed for their metals and PAHs. The species showed similar metal as well as PAHs profile under similar altitudinal gradients in the sequence of F. caperata > P. hispidula > P. sorediata. The difference in pollutant concentrations within each lichen species may be related to intrinsic attributes of the species, such as thallus morphology and the presence of lichen substances which are responsible for the sensitivity and accumulation potential of a particular species. Novelty of the present study lies on the fact that all the species show a similar efficiency of reflecting the environmental condition of the area, albeit the coefficient values of individual species for individual pollutant obtained by three-factor ANOVA revealed that the bioaccumulation affinity of F. caperata is significantly higher than P. hispidula and P. sorediata. For individual metals, F. caperata has a higher affinity for Al, Cr, Fe, Pb and Zn while P. hispidula has a significant positive affinity for Fe and Pb. PCA analysis of sites with respect to pollutant revealed the segregation of sites based on source and distance. Combining the bioaccumulation potential parameters along with geostatistical (GIS) techniques establishes that F. caperata species is a better accumulator of metals and PAHs in comparison to P. hispidula and P. sorediata in the temperate regions of the Himalaya.     

Effects of population and population pressure on forest resources and their conservation: a modeling study

In this paper, a nonlinear mathematical model is proposed and analyzed to study the depletion of forest resources caused by population and the corresponding population pressure. It is assumed that the cumulative density of forest resources and the density of populations follow logistic models with prey–predator type nonlinear interaction terms. It is considered that the carrying capacity of forest resources decreases by population pressure, the main focus of this paper. A conservation model is also proposed to control the population pressure by providing some economic incentives to people, the amount of which is assumed to be proportional to the population pressure. The model is analyzed by using stability theory of differential equations and numerical simulation. The model analysis shows that as the density of population or population pressure increases, the cumulative density of forest resources decreases, and the resources may become extinct if the population pressure becomes too large. It is also noted that by controlling the population pressure, using some economic incentives, the density of forest resources can be maintained at an equilibrium level, which is population density dependent. The simulation analysis of the model confirms analytical results.     

Semen quality of environmentally exposed human population: the toxicological consequence

Human data on the relationship of semen quality with pesticide and metals are mostly inconsistent. The purpose of the study is to confirm the toxicity of organochlorine pesticide β- and γ-hexachlorocyclohexane (HCH), DDE and DDD, and metals lead or cadmium on sperm motility in epidemiological study among fertile and infertile men and to determine whether in vivo and in vitro results are in the same direction. Semen analysis and estimation of the toxicants were done in 60 fertile and 150 infertile men. In the in vitro studies, sperm were exposed to the highest levels of these toxicants found in vivo, as well as five and ten times higher, and to the mixture of all compounds. The study assesses sperm viability and motility for a period ranging between 30 min and 96 h. Epidemiological data showed an inverse correlation of toxicant with sperm motility. In vitro study showed that γ-HCH and lead after 12 h, cadmium after 8 h, and coexposure to toxicants after 6 h of exposure caused significant concentration- and duration-dependent decline in sperm motility. Data of in vitro study were concurrent with epidemiological finding that might be useful in establishing the possible association between exposure and effect of these selected pollutants on sperm motility.     

Bioaccumulation of Ra by plants growing in fresh water ecosystem around the uranium industry at Jaduguda, India

A field study has been conducted to evaluate the ²²⁶Ra bioaccumulation among aquatic plants growing in the stream/river adjoining the uranium mining and ore-processing complex at Jaduguda, India. Two types of plant group have been investigated namely free floating algal species submerged into water and plants rooted in stream & riverbed. The highest ²²⁶Ra activity concentration (9850 Bq kg⁻¹) was found in filamentous algae growing in the residual water of tailings pond. The concentration ratios of ²²⁶Ra in filamentous algae (activity concentration of ²²⁶Ra in plant Bq kg⁻¹ fresh weight/activity concentration of ²²⁶Ra in water Bq l⁻¹) widely varied i.e. from 1.1 × 10³ to 8.6 × 10⁴. Other aquatic plants were also showing wide variability in the ²²⁶Ra activity concentration. The ln-transformed filamentous algae ²²⁶Ra activity concentration was significantly correlated with that of ln-transformed water concentration (r = 0.89, p < 0.001). There was no correlation between the activity concentrations of ²²⁶Ra in stream/riverbed rooted plants and the substrate. For this group, correlation between ²²⁶Ra activity concentration and Mn, Fe, Cu concentration in plants were statistically significant.     

Sowing the seeds of resilience: a case study of community-based Indigenous seed conservation from Andhra Pradesh,India

ABSTRACT

Despite increasing evidence of threats to Indigenous food systems, many Indigenous communities are innovating to enhance their resilience while conserving and promoting their traditional food systems, offering important lessons for rural development policy. This community-based case study explores one such Indigenous initiative: Sanjeevini, in Andhra Pradesh, India. Sanjeevini has been effective in designing and implementing creative strategies for seed sovereignty and biocultural conservation. Interviews with key persons associated with Sanjeevini (n?=?8) and participatory field-research in the Araku Valley region, including interviews with small scale farmers (n?=?30), revealed community development strategies emphasising a link between biological and cultural heritage in Indigenous food systems. These include hosting cultural seed festivals, establishing and maintaining community-based seed banks, and facilitating inter-community seed exchanges. Importantly, these strategies take place against a backdrop of community-organising that counteracts the dominant neo-liberal development agenda while resisting deforestation that threatens Indigenous livelihoods. Sanjeevini’s success demonstrates that through the adaptive assertion of self-determination, rural social change is possible. This paper highlights alternative, community-driven articulations of seed sovereignty while underscoring the significance of this community’s own vision in guiding rural innovation and offering promising working models for cultivating rural resilience.     

Periodical monitoring with lichen, <Emphasis Type="Italic">Phaeophyscia hispidula</Emphasis> (Ach.) Moberg in Dehradun city,Uttarakhand, India

Nine heavy metals were estimated in lichen, Phaeophyscia hispidula (Ach.) Moberg, collected from 12 different sites of Dehradun, capital city, to analyze the air quality of Uttarakhand. Total metal concentration was the highest at Mohkampur Railway Crossing, Hardwar Road (42,505 μg g⁻¹). Dela Ram Chowk, located in the center of the city, also had higher metal concentration, 34,317 μg g⁻¹, with maximum concentration of Pb at 12,433 μg g⁻¹, while Nalapani forest area had minimum total metal concentration (1,873 μg g⁻¹) as well as minimum Pb level at 66.6 μg g⁻¹, indicating anthropogenic activity, mainly vehicular activity, responsible for the increase in metal concentration in the ambient environment. In comparison with the earlier years 2004 and 2006, air pollution as indicated by similar lichen shows a considerable increase in the total metal concentration (especially Pb) in the ambient air of Dehradun city, which may be attributed to exponential rise in the traffic activity in the last 5 years.