Diversity of sediment associated Planctomycetes and its related phyla with special reference to anammox bacterial community in a high Arctic fjord.

The fjords of west Spitsbergen Svalbard, Arctic Norway, are undergoing a transformation as the impact of nutrient rich warmer Atlantic water is significantly altering the primary production and subsequently the carbon pool. Members of the phylum Planctomycetes are ubiquitous in marine systems and are important in the mineralization of organic matter. Hence, the phylogenetic diversity and distribution pattern of Planctomycetes in the surface sediments of a high Arctic fjord, the Kongsfjorden were studied. Further, considering the release of ammonium as a part of mineralization, the diversity of bacterial community involved in anaerobic ammonium oxidation (anammox) was also evaluated. The highly diverse Planctomycetes community, which consisted mainly of uncultivated and uncharacterized Planctomycetes, was observed in the study area with a total of 162 OTUs. The major genera observed were Blastopirellula (13.3%), Gimesia (13%), Rhodopirellula (10%), Planctomicrobium (2%) and Thermogutta (1.6%). Functional prediction revealed the dominance of carbohydrate metabolism genes and the presence of gene clusters for production of secondary metabolites and xenobiotic degradation. Anammox bacterial sequences were detected from all the samples with a total of 52 OTUs. Most of the OTUs belonged to the genus Candidatus Scalindua and three distinct clusters were observed in the phylogenetic tree, (a) Ca. Scalindua brodae (49%), (b) Ca. Scalindua wagneri (31%) and (c) Ca. Scalindua marina (12%) based on their phylogenic distance. Our findings suggest the existence of highly diverse Planctomycetes and anammox bacterial community with regional variants in the sediments of Kongsfjorden.

Vermicomposting of solid waste generated from leather industries using epigeic earthworm Eisenia foetida.

Animal fleshing (ANFL) generated as solid waste from tannery industries was vermicomposted using the epigeic earthworm Eisenia foetida. The mixing ratio of ANFL with cow dung and agricultural residues as feed mixtures was maintained to be 3:1:1 respectively during the vermicomposting experiments for 50 days. Vermicomposting resulted in the reduction of pH 6.74 and C:N ratio 15.5 compared to the control sample. A notable increase in earthworm biomass was also observed in the vermin bioreactor. The germination index of 84% for tomato seedlings (Lycopersicon esculentum cv. PKM1) was observed for the vermicomposted soil. Scanning electron microscope and Fourier transform infrared spectroscopy were recorded to identify the changes in surface morphology and functional groups in the control and vermicomposted samples. The results obtained from the present study indicated that the earthworm E. foetida was able to convert ANFL into nutrient-enriched products.