Alpha-tocopherol supplementation on chromium toxicity: a study on rat liver and kidney cell membrane

Membrane damage is one of the important consequence of chromium,an environmental toxicant,to produce cytotoxicity.α-tocopherol,a membrane protectant can be used to reduce the chromium-induced membrane damage.In the present study,the impact of chromium in presence and absence of α-tocopherol was studied on plasma membrane of live and kidney in male Wistar rats(80-100g body weight).Significant increase in membrane cholesterol level as well as significant decrease in membrane phospholipid level in chromium exposed(0.8mg/100g body weight/d,i.p.,for 4 weeks)animals suggest structural alteration of both liver and kidney plasma memebrane.The alkaline phosphatase,total ATPase and Na^ -K^ -ATPase activities of plasma membrane were significantly decreased in both liver and kidney after chromium treatment.However,α-tocopherol (30mg/100g diet)supplementation can restrict the changes in these membrane-bound enzyme activities.Thus,the usefulness of dietary supplementation of α-tocopherol to restrain the chromium-induced membrane damage is suggested.     

Linking global drivers with local and regional change: a social-ecological system approach in Chilika Lagoon,Bay of Bengal

Global scale drivers such as international markets for shrimp can trigger large changes at local and regional scales. But there is also a poorly appreciated reverse process, operating from the bottom up, with potential for triggering changes at higher scales. Thus, effects of drivers can be seen as a two-way process in which global drivers and local and regional drivers can potentially impact each other. Here, we argue that not only can global drivers impact the sustainability of local and regional social-ecological systems, but sustainability at higher scales can also be impacted by changes at the scale of local and regional social-ecological systems. Using Chilika, a large lagoon on the Bay of Bengal, Odisha State in India as a case, we show that traditional small-scale capture fisheries supporting 150 fisher villages with some 400,000 people were marginalized by aquaculture development for tiger prawn and by state-driven hydrological interventions, with impacts on the ecology of the lagoon. These changes, in turn, contribute to global poverty and food insecurity, making it difficult for India to meet international targets such as millennium development goals. The marginalized fisherfolk become part of environmental justice and other social movements. With large parts of the lagoon converted into a virtual monoculture for the production of tiger prawn, changes in Chilika (a Ramsar site) contribute to wetland habitat loss at the global scale, and biodiversity losses, possibly including IUCN red-listed species.     

Methane oxidation in an intensively cropped tropical rice field soil under long-term application of organic and mineral fertilizers

Methane (CH4) oxidation is the only known biological sink process for mitigating atmospheric and terrestrial emissions of CH4, a major greenhouse gas. Methane oxidation in an alluvial soil planted to rice (Oryza sativa L.) under long-term application of organic (compost with a C/N ratio of 21.71), and mineral fertilizers was measured in a field-cum-laboratory incubation study. Oxidation rates were quantified in terms of decrease in the concentration of CH4 in the headspace of incubation vessels and expressed as half-life (t(1)2) values. Methane oxidation rates significantly differed among the treatments and growth stages of the rice crop. Methane oxidation rates were high at the maximum tillering and maturity stages, whereas they were low at grain-filling stage. Methane oxidation was low (t(1)2) = 15.76 d) when provided with low concentration of CH4. On the contrary, high concentration of CH4 resulted in faster oxidation (t(1)2) = 6.67 d), suggesting the predominance of "low affinity oxidation" in rice fields. Methane oxidation was stimulated following the application of mineral fertilizers or compost implicating nutrient limitation as one of the factors affecting the process. Combined application of compost and mineral fertilizer, however, inhibited CH4 oxidation probably due to N immobilization by the added compost. The positive effect of mineral fertilizer on CH4 oxidation rate was evident only at high CH4 concentration (t(1)2 = 4.80 d), while at low CH4 concentration their was considerable suppression (t(1) = 17.60 d). Further research may reveal that long-term application of fertilizers, organic or inorganic, may not inhibit CH4 oxidation.     

Colourimetric analysis and antimicrobial study of natural dyes and dyed silk

Colourimetric and antimicrobial activities of natural colourants and dyed silk have been studied. The colour strength (K/S) values were increased with increase in dye absorbance. The absorption of dyes on silk yarns was obtained from 10.56 to 39.48% at 5% concentration of dye from different plant extracts. The colourimetric parameters L¹, a¹, b¹, C, and H were measured for depth of the colour. The dyed silk with natural colourants displayed excellent antimicrobial activity (reduction rate: 25–65%) against the bacteria Escherichia coli and (reduction rate: 3–68%) against the fungal strain Aspergillus niger. The dyed silk exhibited good and durable fastness properties.     

Agricultural GHG emission and calorie intake nexus among different socioeconomic households of rural eastern India

A study was conducted to examine the interrelationships among socioeconomic factors, household consumption patterns, calorie intake and greenhouse gas emissions factors in rural eastern India based on household survey data. Findings indicated that higher monthly per capita incomes (12.1–80.1$) were associated with greater average calorie intakes (2021–2525 kcal d^?1). As estimated by the FEEDME model, in total 17.2% of the population was calorie malnourished with a regional disparity of 29.4–18.2% malnourishment. Greenhouse gas (GHG) emissions were calculated only on the basis of crop and livestock production and consumption. Rice accounted for the highest share of total GHG emissions, on average 82.6% on a production basis, which varied from 58.1% to 94.9% in regional basis. Rice contributed the greatest share (~?65% and 66.2%) in terms of both calories and GHG emissions (CO₂ eq y^?1), respectively, on a consumption basis. We conclude that extensive rice farming and increasing animal product consumption are dominant factors in the higher carbon footprint in this region and are likely to further increase with increase in per capita income. This study provides useful information to help for better crop planning and for fine-tuning food access policy, to reduce carbon footprint and calorie malnutrition.

     

Environmental studies on river water quality with reference to suitability for agricultural purposes: Mahanadi river estuarine system, India – a case study

Hydrochemistry of surface water (pH, specific conductance, total dissolved solids, sulfate, chloride, nitrate, bicarbonate, hardness, calcium, magnesium, sodium, potassium) in the Mahanadi river estuarine system, India was used to assess the quality of water for agricultural purposes. The samples were studied for 31 different stations during six different seasons in the years 2001-2003. Chemical data were used for mathematical calculations (SAR, Na%, RSC, potential salinity, permeability index, Kelly's index, magnesium hazard, osmotic pressure and salt index) for better understanding the suitability river water quality for agricultural purposes. The river water is free from nitrate-nitrogen hazard and has much less osmotic pressure and RSC values. Further there is no complete precipitation of calcium and magnesium in the study area. The results revealed that waters of some polluted stations like Sambalpur down (D/s of Sambalpur town) and Kathjodi (Cuttack) down (D/s of Cuttack town) are unsuitable up to some extent, where as it is quite unsuitable in case of estuarine samples during the pre-monsoon and post-monsoon seasons. The results were verified by USSL and Wilcox diagrams, which show all the fresh water zone samples (low-medium salinity with low sodium) of the study area are in the 'Excellent to good' category and are suitable to irrigate all soils for semi-tolerant and tolerant as well as sensitive crops.     

Long-term effect of rice-based farming systems on soil health

Integrated rice–fish culture, an age-old farming system, is a technology which could produce rice and fish sustainably at a time by optimizing scarce resource use through complementary use of land and water. An understanding of microbial processes is important for the management of farming systems as soil microbes are the living part of soil organic matter and play critical roles in soil C and N cycling and ecosystem functioning of farming system. Rice-based integrated farming system model for small and marginal farmers was established in 2001 at Central Rice Research Institute, Cuttack, Odisha. The different enterprises of farming system were rice–fish, fish–fingerlings, fruits, vegetables, rice–fish refuge, and agroforestry. This study was conducted with the objective to assess the soil physicochemical properties, microbial population, carbon and nitrogen fractions, soil enzymatic activity, and productivity of different enterprises. The effect of enterprises induced significant changes in the chemical composition and organic matter which in turn influenced the activities of enzymes (urease, acid, and alkaline phosphatase) involved in the C, N, and P cycles. The different enterprises of long-term rice-based farming system caused significant variations in nutrient content of soil, which was higher in rice–fish refuge followed by rice–fish enterprise. Highest microbial populations and enzymatic properties were recorded in rice–fish refuge system because of waterlogging and reduced condition prolonged in this system leading to less decomposition of organic matter. The maximum alkaline phosphatase, urease, and FDA were observed in rice–fish enterprise. However, highest acid phosphatase and dehydrogenase activity were obtained in vegetable enterprise and fish–fingerlings enterprise, respectively.     

Response of diazotrophic cyanobacterium Nostoc carneum under pesticide and UV-B stress

A study was under taken, under controlled laboratory conditions, to investigate the influence of non-ionizing radiation (UV-B) and an organochlorine pesticide on the growth, photosynthetic pigments, protein content and DCPIP photoreduction of a cyanobacterium Nostoc carneum. Test algae was isolated from rice field soils of Sambalpur, Western Orissa, India and grown in nitrogen free BG 11 culture medium. Culture of algae from log phase of growth was treated with 5 ppm of the insecticide, Endodhan and UV-B (20 mW m⁻²) for 2 h daily, separately and in combination of insecticide and UV-B radiation. Algal samples treated with UV-B and pesticide separately showed distinct inhibitory effects on growth, pigments, protein content and DCPIP reduction of the test samples. However, when pesticide treated samples were subjected to UV-B exposure, the effect showed additive as well as synergetic effect. Experiment conducted to check the ability of the organism to recover from the stress, exposed for various time periods, suggest their ability to partially recover from the stress.