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

Comparative study on pre-treatment methods for enhanced saccharification from tropical seaweeds to aid in bioethanol production

The selection of suitable pretreatment strategy that facilitates saccharification is the most critical step in the valorisation of seaweed biomass into bioethanol. Considering the scarcity of data on the comparative efficacy of different pretreatments particularly in tropical seaweed species, 50 pretreatment strategies were analysed on three major species representing all the three broad seaweed categories, viz. Ulva fasciata (green algae), Sargassum wightii (brown algae), and Gracilaria corticata (red algae). An improved release of reducing sugars was observed in all the tested pretreatments, with different conversion ratios for different species in each pretreatment. Ultrasonication and magnetic stirring showed maximum yield among physical pretreatments. In thermal methods, microwave oven incubation resulted in maximum yield from both U. fasciata and S. wightii, while it was autoclaving for G. corticata. Sulphuric acid was the best chemical for U. fasciata and G. corticata, while it was orthophosphoric acid for S. wightii. Hydrochloric acid was the best chemical for physicothermochemical pretreatment in all species. Maximum conversion ratios of 2.58, 2.11, and 2.0 were recorded in U. fasciata, G. corticata, and S. wightii respectively. In short, the paper sketches the best pretreatment method for three major tropical seaweeds along with their proximate composition. The results can be applied for aiding the valorisation of biomass of these seaweeds through a cost-effective manner