Preliminary assessment, restoration and aquaculture support for a small wetland

In line with the strategy of regional wetland datasets integration to a common national digital platform, map of small wetlands less than 2.2 ha in Kochi Taluk was prepared. A representative small wetland at Edakochi village of Kerala was selected through maps and field visits for preliminary assessment and restoration. Shuttle Radar Topography Mission’s Digital Elevation Model (DEM) was used to assess the general elevation, slope and flow accumulation pattern of the selected wetland along with assessment of the catchment area and drainage pattern. Restoration works of the selected wetland was carried out vis-a-vis side bund strengthening and sluice gate fortification. The comparative analysis of water quality assessment of wetland before and after restoration revealed improvement in water quality parameters as well as increase in water level. The Dissolved Oxygen level of the aquatic system was found to have increased substantially along with other several favourable changes in water parameters due to the restoration activities. The restored wetland at Edakochi was further utilised for multispecies farming of prawns, Pearl spot, Milk fish and Grey mullet and the harvest indicated sustainable yield. Aquaculture practice in wetlands with real time scientific advisories could ensure continuous data generation and village level climate resilience

Climate change drivers influencing Indian mackerel fishery in south-eastern Arabian Sea off Kerala, India

The Indian mackerel Rastrelligerkanagurta(Cuvier, 1816) is one of the most important marine fishery resources along the south-eastern Arabian Sea along the coast of Kerala, south India. The effect of selected environmental variables on the Relative effort (Effort) and weighted catch per unit effort (cpue)of the fish were investigated using simple correlation and Path analysis. Six major oceanographic variables, namely sea surface temperature (SST), sea surface chlorophyll-a concentration (SSC), sea surface salinity (SSS), Precipitation (Pr) Indian Ocean Dipole (IOD) and Southern Oscillation Index (SOI) (ENSO index) were selected for the present study. Among these SST had the highest direct negative effect (-0.282, p SSC >SSS

Population genetics of the narrow endemic Hlandnikia pastinacifolia Rchb. (Apiaceae) indicates survival in situ during the pleistocene

Hladnikia pastinacifolia Rchb., a narrow endemic, has an extremely restricted distribution in Trnovski gozd (Slovenia), despite the presence of many sites with suitable habitats. We compared the morphological traits of plants from different populations and habitats. The overall pattern showed that the smallest plants, with low fruit number, are found on Èaven (locus classicus or type locality); the largest individuals, with high fruit number, grow in the Golobnica gorge. As judged by plant size and seed set, the optimal habitats are screes. We used RAPD markers to estimate genetic variation between and within populations, as well as between and within the northern and the southern parts of the distribution area. Hladnikia showed only a low level of RAPD variability. AMOVA partitioned the majority of genetic diversity within selected populations. The low genetic differentiation between populations and their genetic depauperation indicates survival in situ, since the Trnovski gozd plateau most likely was a nunatak region in the southern Prealps during Pleistocene glaciations. Later range expansion of extant populations was limited by poor seed dispersal. We also analyzed the cpDNA trnL-F intergenic spacer to check whether the sequence is useful for studying the phylogenetic relationships of Hladnikia within the family Apiaceae (Umbelliferae). Our results support the assertion that H. pastinacifolia is an old taxon

An Overview of Graphene-Based 2D/3D Nanostructures for Photocatalytic Applications

Photocatalytic processes induced by inexhaustible solar energy have fascinated significant research to solve issues like energy crisis and environmental pollution since they possess several merits, like renewable energy sources, safety and low operating cost. Photocatalysis is also considered as one of the environment-friendly sustainable methods for the degradation of organic contaminants. The conversion of CO2 into hydrocarbon fuel with low energy via photocatalytic reduction is another application of this field that can realize the efficient conversion and storage of solar energy to chemical energy and the recycling of carbon in practical applications. Furthermore, this clean technique is commonly employed in water treatment, bacteria disinfection, and selective organic compound synthesis. The graphene-based two-dimensional (2D) and three-dimensional (3D) nanostructures can solve many issues of using conventional photocatalysts; due to their versatile properties, including peculiar morphology, surface area, stability, optical adsorption, electrical, electrochemical and photoelectrochemical properties. The main highlight for the graphene-based structures is the synergism between the adsorption and photocatalytic activity in removing organic pollutants. This review mainly presents an overview of the processes/mechanisms and evolution strategies for developing graphene-based 2D/3D nanostructured systems. Various applications of graphene-based heterostructured photocatalysts were also detailed. The ongoing challenges and significant state-of-the-art advances on graphene-based systems are also discussed in this review.Funding was provided by Qatar Foundation (NPRP Grant # NPRP11S-1221-170116).Scopu

Bifunctional Luminomagnetic Rare-Earth Nanorods for High-Contrast Bioimaging Nanoprobes

Nanoparticles exhibiting both magnetic and luminescent properties are need of the hour for many biological applications. A single compound exhibiting this combination of properties is uncommon. Herein, we report a strategy to synthesize a bifunctional luminomagnetic Gd2-xEuxO3 (x = 0.05 to 0.5) nanorod, with a diameter of similar to 20 nm and length in similar to 0.6 mu m, using hydrothermal method. Gd2O3:Eu3+ nanorods have been characterized by studying its structural, optical and magnetic properties. The advantage offered by photoluminescent imaging with Gd2O3:Eu3+ nanorods is that this ultrafine nanorod material exhibits hypersensitive intense red emission (610 nm) with good brightness (quantum yield more than 90%), which is an essential parameter for high-contrast bioimaging, especially for overcoming auto fluorescent background. The utility of luminomagnetic nanorods for biological applications in high-contrast cell imaging capability and cell toxicity to image two human breast cancer cell lines T47D and MDA-MB-231 are also evaluated. Additionally, to understand the significance of shape of the nanostructure, the photoluminescence and paramagnetic characteristic of Gd2O3:Eu3+ nanorods were compared with the spherical nanoparticles of Gd2O3:Eu3+

Impact of climate change on the fishery of Indian mackerel (Rastrelliger kanagurta) along the Kerala coast off the southeastern Arabian Sea

Climate change impact varies at regional as well as species level and accordingly research needs to be focused on exploring the region-wise influence of oceanographic variations on key marine species. The present study depicts the annual and decadal fluctuations in Indian mackerel fishery along Kerala coast of southeastern Arabian Sea over a time period of 31 years (1985–2016), its relationship between four major oceanographic variables (SST, Pr, SSS and SSC) and future predictions under two Representative Concentration Pathways (RCPs). Coast specific changes of these oceanographic variables since 1960 provide a baseline status of the existing climatic conditions of the marine ecosystem of the SEAS whereas, the RCP projections till 2100 provide an insight to the future conditions. Generalized Additive Models (GAMs) has been used to comprehend the relation among the Weighted CPUE (cpue) and Relative effort (Effort) of Indian mackerel and the four major oceanographic variables. The GAM model could explain 68.9 % and 71.1 % deviance of cpue and Effort respectively. The significance of the most influential oceanographic variables on the cpue of Indian mackerel were in the order SST > Pr > SSC > SSS and for Effort were in the order Pr > SST > SSS > SSC. The projected cpue and Effort of Indian mackerel exhibits varying trends under the RCP 4.5 and RCP 6.0 scenarios. The future catch potential of Indian mackerel predicted under both RCP scenarios for the period 2020–2100 also show reduction, with the latter exhibiting a more drastic reduction. The study implies that for sustainable long-term fishery and to reduce the impact of climate change on Indian mackerel, the fishing pressure has to be maintained at low and healthy level

Tunable luminescence from two dimensional BCNO nanophosphor for high-contrast cellular imaging

Rare-earth free and biocompatible two dimensional carbon based boron oxynitride (2D BCNO) nanophosphors were synthesized using facile auto-combustion of inexpensive compounds such as urea, boric acid and polyethylene glycol at ambient atmosphere and relatively low temperatures. The surface morphology and microstructure images indicate that the nanophosphor has 2D layered structures and analogous mixed hexagonal lattices of boron nitride (BN) and graphene (C). The nanophosphor exhibits a single, distinct and broad photoluminescence emission and this emission colour can be easily tuned from violet to deep red by varying the amount of boron/carbon content. The time-resolved and photoluminescence spectroscopic results indicate that B-O act as luminescence centers, which are responsible for the tunable luminescent properties while carbon impurities induce energy levels in the band gap of 2D BCNO nanophosphors. These tunable and biocompatible luminescent nanophosphors are used for in vitro high-contrast cellular imaging of HeLa cells derived from human cervical cancer cells as well as in vivo imaging in C57BL/6J mice. Hence, these novel multi-colour emitting nanophosphors provide a paradigm shift in rare-earth free biocompatible nanoprobes for next generation high-contrast in vitro and in vivo imaging applications