Studies on biosorption of nickel using immobilized fungus, Rhizomucor tauricus

Rhizomucor tauricus, an industrial fungus, was immobilized in sodium alginate and used as adsorbent for the removal of nickel from aqueous solutions. The biosorption capacity of Ni(II) was found to be 394 mg/g of immobilized biomass. It was observed that an increase in pH from 3 to 6 increased the percent adsorption, and an increase in liquid-to-solid ratio from 2 to 10 increased the metal uptake. The percent adsorption was increased when increasing the initial metal concentration from 25 to 100 mg/L. The equilibrium biosorption data was evaluated by Langmuir, Freundlich, and Langmuir-Freundlich (L-R) isotherm models, and was best described by the Langmuir and Freundlich isotherms. FTIR analysis revealed that –NH (bending), C–H (stretching), C=O (stretching), and –OH functional groups were mainly responsible for Ni(II) biosorption. Thus, this study demonstrated that the immobilized Rhizomucor tauricus biomass could be used as an adsorbent for the treatment of Ni(II) from aqueous solution

Bio-inoculated Nutrient Management Influence on Soil Nutrient Availability Pattern and Growth of Hybrid Pigeonpea (ICPH 2740) under Establishment Methods and Crop Geometry

Background A two-year field study was conducted at the ICRISAT research farm during the rainy seasons of 2021 and 2022 to investigate the impact of crop geometry, crop establishment method and sustainable nutrient management practices on nutrient availability pattern and growth of hybrid pigeon pea. Methods The experiment followed a split-split plot design. The collected data was analysed using radar graph and heat maps for nutrient availability and dry matter respectively. Result Data revealing that transplanted plots registered higher nutrient availability and proportionate root and total dry matter production at various growth stages. Among plant geometry the root and total dry matter production was higher with 100×100 cm. when considering planting methods, transplanting with a square system of 100×100 cm, combined with an integrated nutrient management approach consisting of 150% (or) 100% soil test based NPK, vermicompost at a rate of 5 t ha-1, phosphate-solubilizing bacteria (PSB) and seed treatment with Rhizobium, resulted in average of 31.5% higher dry matter production over alone inorganic nutrient management practices. Thus, a square geometry of 100×100 cm, along with sustainable integrated nutrient management (100% soil test based NPK, vermicompost at a rate of 5 t ha-1, PSB and seed treatment with Rhizobium), resulted in higher nutrient availability and dry matter production. These findings highlight the importance of careful selection of planting methods, crop geometry and nutrient management practices for maximizing the nutrient mining for production of high dry matter production of hybrid pigeonpea

Prawn fauna (Crustacea: Decapoda) of India - An annotated checklist of the Penaeoid, Sergestoid, Stenopodid and Caridean prawns

Twenty four species of Pandalid shrimps reported from the Indian waters, of which six genera (Chlorotocella, Chlorotocus, Chlorocurtis, Dorodotes, Heterocarpoides and Stylopandalus) are represented by single species each. The genera, Plesionika and Heterocarpus are represented by eleven and seven species respectively. Plesionika adensameri (Balss, 1914) a deep-sea shrimp hitherto unreported from Indian waters is recorded from west coast of India. Information on some biological aspects of few Pandalid shrimps from Indian waters is also reported in the present paper

Stock assessment of the penaeid prawn Metapenaeus dobsoni (Miers) along the Indian coast

The annual prodiction of M. dobsoni showed an increasing trend with an annual average of 22 370 t during 1985-S9. It formed 15.7% of the penaeid prawn landings in the country. West coast contributed 69.9% to the annual yield of this prawn. Kerala ranked first (51.4%) in M. dobsoni production followed b;' Tamil Nadu. Shrimp trawl alone caught 54% of the landings. L«> and K were 139 mm and 2.4 for m«les, and 145 mm and 2.76 for females respectively. The instantaneous mortality coefficient (Z) ranged lietween 16,47 and 25.29 in males, and between 16.21 and 20.97 in females. Tlie natural mortality coefficient (M) was 2.3 for both the sexes. The yield per recruit (Yw/R) increased steadily to maximum values (MSY/R) in both the sexes at Emax ranging between 0.2 and 0.4. It marginally reduced at Ihe present E between 0.8 and 0.9 suggesting that the resource is overexploited and the current effort s far higher than the effort required to harvest optimum yields. Although the average annual catch by shrimp trawls (12 189 t) is lower than MSY (13 965 t), the annual effort of 6 920 tpd or 1 488 000 bd (F= 17.8 and E = 0.89) is far beyond f^,. Considering the fact that this prawn is also exploited by other gears with an annual average of 10 180 t during 1985-89, a conservative estimate of 25 000 t as potential stock for the whole country is made

Appraisal of trawl fisheries of India with special reference on the changing trends in bycatch utilization

Trawl fisheries sector account more than 50% of the marine fisheries production of India. Annual average fish landing from trawlers was 17, 21, 000 t (2008-2011), which formed around 51 % of the marine fish landing of the coast. In this about 51% of the catch was contributed by the west coast and remaining by the east coast of India. Recent studies of the trawl fishery in India have shown that incidental catches/low value bycatch (LVB) landing and utilization has increased over the period of time. The present study is based on the data collected from major trawl landing centres along the coast of India during the period 2008-2011.The estimated landing of low value bycatch (LVB) in trawl fisheries, increased from 14 % in 2008 to 25 % in 2011, which is reflected as reduction in discard volume by trawlers. On an average the highest quantity of LVB landed was in Veraval (50,000 t) and in Mangalore, LVB landing increased from 3% in (3000 t) in 2008 to 26 % (12,000 t) in 2011.In Mumbai, the percentage of trash fish landed remained around 5% during the study period. In Calicut, the LVB landed in 2011 contributed 26% to the total landings by the trawl. In Kochi, Kerala the total LVB landed in 2011 was 1,992 t forming 7.2 % of the total landing. In Chennai, Tamilnadu, the LVB landing which was 13 % in 2008 increased to 17% in 2011, while in Visakhapatanam, Andhra Pradesh, LVB landing showed a steady increase from 2% in 2008 to 21% in 2011. The landing centre price for LVB showed an increasing trend due to increased demand for trash fish for the production of fish meal and fertilizer. The dominance of finfishes in LVB found to increase the value of LVB and the value realized for 30,000 t of LVB in Available online at: www.mbai.org.in doi: 10.6024/jmbai.2013.55.2.01765-11 Mangalore in 2011 ( Rs.280 million) was more than that realized for 50,000 t of LVB in Veraval (Rs.200 million). A disturbing trend observed from the studies in Mangalore was that, the sardines in trash fetches higher price in some seasons (upto Rs.16/kg) compared to a lower price when landed in fresh form, and the percentage of sardines in LVB is found to be very high (24% in 2010). This trend may cause a severe threat to the protein availability to the rural poor. Looking at the trend of trawl landing during 2008-2012, it is seen that even though the trawl landing showed an increase over the period of time, the edible portion of the trawl landing did not show any significant increase rather showing general declining trend. Study on the bycatch from different centres along the coast of India showed that as many as 237 species / groups of marine fauna with juveniles of commercially important fishes were landed as LVB. Increase in utilization of LVB (which was discarded earlier) from trawl fishery, a trend which is market driven and its implication on the ecosystem and marine fisheries production of the country is discussed in this paper

Bycatch in Indian trawl fisheries and some suggestions for trawl bycatch mitigation

Globally, trawl is the major fishing gear used in marine fisheries and in India, it contributes to more than onethird of the marine fish production. Trawl fishing has been critically evaluated from a sustainability perspective, especially analysing its bycatch composition. Most of the bycatch from trawlers contains valuable edible species with high market demand. However, a portion of the bycatch which does not have such demand in the edible fish market, known as low-value bycatch (LVB), continues to be a matter of concern from an ecological and economic perspective. During 2017–19, 30–60% of trawl landing in India was constituted by LVB, which was mainly used for fishmeal preparation. To enhance the value and utility of LVB, this study explores the possibility of converting waste from LVB into edible resources using pufferfish and triggerfish. It also highlights the positive impact of efforts by different Government agencies for bycatch mitigation like the implementation of minimum legal size in reducing the juvenile component in bycatch, with a social survey-based account of fisher’s perceptions and suggestions on successful bycatch mitigation

Multi-layered fractured aquifer characterization: a comparative study

An effective framework for groundwater modelling is a precursor for sustainable management of regional water resources. Owing to the coexistence of contrasting hydrogeological units, modelling of groundwater flow through multi-layered fractured aquifers such as the granitic aquifers found in the Deccan region of India, requires an accurate estimation of hydraulic parameters and delineation of preferential flow-paths. There are several approaches towards this goal. This study compares seven methods by evaluating their abilities to reconstruct the hydraulic parameter distributions of a synthetic two-dimensional multi-layered aquifer analogue whose construction is based on pre-existing field data. The methods studied are (1) a homogeneous parameter model; (2) a single-hole equivalent model that provides an average of local-scale estimates; (3) a geostatistical single-hole model that involves kriging of the single-hole local-scale estimates; (4) a uniformly placed pilot-point model; (5) the sequential successive linear estimator (SSLE) algorithm; (6) a geostatistical-guided pilot-point model; and (7) a new approach that involves a pilot-point model guided by the results of the SSLE algorithm. The results of the inversions are compared visually using tomograms and by a statistical analysis of the time-drawdown datasets obtained from validation wells that were not used for calibrating the models. The uniform pilot-point model performed significantly better than the other methods. The SSLE algorithm recovered the fracture connectivity pattern with significant fidelity. Using the SSLE algorithm as a guide improved the parameter estimation at the cost of the fracture connectivity pattern. © 2021, Springer-Verlag GmbH Germany, part of Springer Nature