Advanced treatment technologies efficacies and mechanism of per- and poly-fluoroalkyl substances removal from water

© 2020 Institution of Chemical Engineers The increasing occurrence of chemically resistant per- and poly-fluoroalkyl substances (PFASs) in the natural environment, animal tissues and even the human body poses a significant health risk. Temporal trend studies on water, sediments, bird, fish, marine mammal and the human show that the exposure of PFAS has significantly increased over the last 20–30 years. Different physical, biological and chemical treatment processes have been investigated for PFAS removal from water. However, there is a lack of detailed understating of the mechanism of removal by different methods, especially by different advanced chemical treatment processes. This article reviews PFASs removal efficacy and mechanism by the advanced chemical treatment methods from aqueous solution. Review shows that several advanced oxidation processes (e.g., electrochemical oxidation, activated persulfate oxidation, photocatalysis, UV-induced oxidation) are successful in degrading PFASs. Moreover, defluorination treatment, some thermal and non-thermal degradation processes are also found to be prominent for the degradation of PFASs with some limitations including process costs over physical treatment (e.g., sorption), production of toxic by-products and greenhouse gases. Finally, knowledge gaps concerning the advanced chemical treatment of PFASs are discussed

Comparative genomics of two jute species and insight into fibre biogenesis

Jute (Corchorus sp.) is one of the most important sources of natural fibre, covering ∼80% of global bast fibre production1. Only Corchorus olitorius and Corchorus capsularis are commercially cultivated, though there are more than 100 Corchorus species2 in the Malvaceae family. Here we describe high-quality draft genomes of these two species and their comparisons at the functional genomics level to support tailor-designed breeding. The assemblies cover 91.6% and 82.2% of the estimated genome sizes for C. olitorius and C. capsularis, respectively. In total, 37,031 C. olitorius and 30,096 C. capsularis genes are identified, and most of the genes are validated by cDNA and RNA-seq data. Analyses of clustered gene families and gene collinearity show that jute underwent shared whole-genome duplication ∼18.66 million years (Myr) ago prior to speciation. RNA expression analysis from isolated fibre cells reveals the key regulatory and structural genes involved in fibre formation. This work expands our understanding of the molecular basis of fibre formation laying the foundation for the genetic improvement of jute. Bast (phloem) fibres are obtained from the stem of the plants such as jute, flax, hemp, ramie and kenaf. The annual global production of jute generates a farm value of ∼US$2.3 billion1. The cultivated species of jute, C. olitorius and C. capsularis, are morphologically and physiologically distinct (Supplementary Fig. 1), and a combination of useful traits from these species into a single genotype is highly desirable3. However, interspecific hybridization is limited because of their cross-incompatibility4,5. To facilitate comparative functional genomics and to understand the molecular basis of bast fibre biogenesis, genomes of two popular jute cultivars C. olitorius var. O-4 and C. capsularis var. CVL-1 are sequenced and analysed

Modelling of irrigation reservoir operation for efficient water management with focus on water and food security

Agriculture uses more water when compared with other water users. Insufficient water resources in a country would create additional issues of governance due to poor food security for its people and lack of water for the sustenance of the environment. Water shortages especially for agriculture are most felt in the dry zone in Sri Lanka and most of the farmers are failing to cultivate full extent in both Maha and Yala season. Irrigation Department Guideline (ID 1984) which is the base for reservoir operation, planning and management in Sri Lanka, has the need to improve its methods by identifying suitable parameters and operational options suited for field applications. There are only limited studies of reservoir operation practice in Sri Lanka. Twenty years (1997-2016) of reservoir operation data of Namal Oya reservoir at Ampara District, Sri Lanka were analyzed at a weekly time scale to compare the practice and the guideline to critically evaluate the requirements for better water management with a view of achieving water security and thereby reaching food security. This work is an evaluation of irrigation reservoir water management practice to make recommendation for efficient water management in order to achieve water and food security for farming communities in the dry zone of Sri Lanka. A weekly water balance model according to the Irrigation Department guideline was developed for the reservoir system while including the behavior of the catchment area and the practice of cultivation in the command area. The model development was carried out using spreadsheets. A weekly crop water requirement was also developed to check observed water release which were compared with the crop water model estimations to verify the adherence to the guidelines. These results were then compared with the actual water releases to evaluate the variations, influence of parameters and the field level cultivation practices. Inflow model was also developed based on Irrigation department guideline and a monthly 2 Parameters model and were later compared with observed storage. The comparison of model developed with ID guideline and the water use plans of the Namal Oya Irrigation department office revealed the average annual difference of observed and calculated water release is 1091 Ha.m where 392 Ha.m in Maha season and 699 in Yala season and observed annual water release is 2098 Ha.m where 705 Ha.m in Maha and 1391 Ha.m in Yala which indicating the Namal oya Irrigation reservoir are releasing 50% more water than the observed values in a water year. The model results and the actual practice demonstrated that the overall efficiency of the irrigation scheme is estimated based on trial and error method and the value is 55%. The most sensitive parameters in the water balance inflow, sluice release and seepage. The study indicated that if the efficiency level can be increased by 70%, the annual water demand will be reduced from 2654.82 Ha.m to 2055 Ha.m which enables to served nearly 496 Ha more command area each water year. The key parameters that need attention are inflow andsluice discharges. Consideration of practical advantages and the need for water security leads to recommending to incorporate the present practice with an update of ID guideline

Comparative efficacy of garlic, BAU-biofungicide, Bavistin and Tilt on seed borne fungal flora in chilli

Efficacy of BAU-Biofungicide (3%), garlic extract (1:1), Bavistin (0.2%) and Tilt 250EC (0.2%) were evaluated against seed borne fungal pathogens of chilli collected from Lakshmonkhola, Mugarchar and Tulatuli villages under Comilla district. Four hundred seeds of each sample were tested following blotter incubation and sand culture method. Using blotter incubation method, five different seed borne fungi, namely, Colletotrichum capsici, Alternaria tenuis, Aspergillus spp, Fusarium spp, and Curvularia lunata were detected from the chilli seeds. BAU-Biofungicide (3%) and followed by garlic extracts (1:1) was found most effective among five different treatments for increasing the germination percentage as well as controlling the associated seed borne fungi in chilli seed. Highest germination percentage (89.50%) was observed in BAU-Biofungicide (3%) treated seeds. Highest reduction of Colletotrichum capsici, Alternaria tenuis, Aspergillus spp, Fusarium spp, and Curvularia lunata was observed when seeds were treated with BAU-Biofungicide (3%) and garlic extract (1:1). The highest vigour index of chilli seed collected from Lakshmomkhola, Mugarchar and Tulatuli villages were 494.56, 403.23 and 333.37, respectively was observed in BAU-Biofungicide treated seeds