Manganese as a Micronutrient in Agriculture: Crop Requirement and Management

Manganese (Mn) as an essential plant micronutrient affects plant development, when at deficient or toxic levels. Manganese is used in several biological processes as an important contributor in plant growth and development. Manganese uptake depends on forms of Mn in soil solution, crop characteristics including growth rate, and ineteractions with other environmental factors. Its distribution in soils and requirement for crops vary from location to location, depending on soil type and reactions. Despite the metabolic roles of Mn in different plant cell compartments, the importance of Mn requirement in plants, distribution in soils and application to crops has been understated. As a micronutrient, judicious Mn management requires to critically evaluating its concentration in soils, biochemical functions, critical levels, soil availability and interactions with other nutrient elements is essential. This review has critically analysed the existing body of knowledge on Mn distribution in soils, dynamics, functions and management towards better crop production and safe environment. Environ. Sci. & Natural Resources, 12(1&2): 225-242, 2019

Effects of 2017 Early Flash Flooding on Agriculture in Haor Areas of Sunamganj

The Sunamganj district is covered by major Haor systems in the north-eastern region of Bangladesh. Flash flood is the most commonly occurring water related disaster in the Haor areas. During the flash flood it is very common that people lost their primary agricultural productions which are the only source of their livelihood. The present study focuses on the effects of 2017 early flash flooding on rice and fish production of Sunamganj Haor areas. The flood caused enormous damage to agriculture such as rice especially Boro rice and fish production on which the Haor dwellers rely upon for their livelihood. The total affected land of Boro rice cultivation in Haors of Sunamganj was 149,224 hectare and the total amount of damaged rice was 393,855 metric ton (MT). The total number of affected farmers was 315,084. The early flash flood also affects the quality of Haor water which caused the death of fishes. The total amount of damaged fish was 49.75 MT and the loss was 158.70 lakh taka. The total number of affected fishermen was 44,445. This findings could be very useful for the environmental scientists to predict the probable future effects on agricultural production due to early flash flood events in Sunamganj Haors areas. Environ. Sci. & Natural Resources, 12(1&2): 117-125, 2019

Comparative Study on Proximate Composition and Heavy Metal Concentration of Molacarplet (Amblypharyngodon mola) and Spotted Snakehead (Channa punctatus) Collected from Pond Water and Open Water

A study was conducted on the proximate composition and heavy metal concentration of Amblypharyngodon mola and Channa punctatus collected from pond water and open water in Mymensingh. The proximate composition analysis result showed -protein, lipid, moisture and ash content (%) of pond water A. mola were 20.26±0.63, 6.70±0.17, 66.40±1.51 and 2.55±0.58, respectively and for the fish caught from open water the values were 19.66±0.75, 5.81±0.18, 63.03±0.82 and 2.92±0.15, respectively. On the other hand, protein, lipid, moisture and ash content (%) of pond water C. punctatus found 23.83±1.07, 5.91±0.11, 64.44±1.87 and 3.23±0.11, respectively whereas the values for the fish caught from open water were 22.21±0.66, 5.43±0.19, 62.73±1.65 and 3.67±0.47, respectively. Arsenic (As) concentration of A. mola was higher in open water fishes (0.23±0.05 μg g-1) than the fishes of pond water (0.14±0.03 μg g-1). Cd concentration of pond water C. punctatus was found 0.21±0.04 μg g-1 whereas open water fishes contained 0.28±0.06 μg g-1. Copper (Cu) concentration of pond water and open water A. mola was 0.27±0.07 μg g-1 and 0.32±0.04 μg g-1, respectively. Heavy metal concentration of A. mola and C. punctatus was within permissible limits except Cd. The result revealed that open water fishes had higher concentration of heavy metals in their muscle than the fishes of pond water. Environ. Sci. & Natural Resources, 12(1&2): 91-99, 2019

Drinking Water Supply Options in Arsenic and Salinity Affected Areas of Bangladesh: A Case Study

Widespread groundwater arsenic contamination in south, south-western and north-eastern regions and high salinity in the south-western coastal region are the two major challenges for drinking water supply in Bangladesh. In this study, we assessed various water supply technologies used for mitigating arsenic and salinity in Laksam of Cumilla and Assasuni of Satkhira district. Water samples were analyzed for Arsenic, Iron, Chloride (indicator for salinity) and FC from different water extraction systems (shallow, deep and Tara tubewells), groundwater arsenic treatment units (SIDKO and READ-F), rainwater harvesting systems (RWH), pond sand filters (PSF), and managed aquifer recharge units. Most shallow tubewells, both in Laksam and Assasuni, have been found to produce arsenic contaminated water. But water from deep and Tara tubewells have been found arsenic-free, though high concentration of iron was observed in the wells in Laksam. Rainwater harvesting systems, PSF and MAR units in Assasuni have been found to provide water free from the common chemical contaminants but suffer from high bacterial contamination. Deep tubewell appear to be the most preferred option where a suitable aquifer is available. The community-scale groundwater treatment systems would require strong operation and maintenance support from the service providers to be successful. Environ. Sci. & Natural Resources, 12(1&2): 215-223, 2019

Storage Effects of Low Temperature on the Quality Parameters of Mince Based Fish Stick Prepared from Silver Carp (Hypophthalmichthys molitrix)

It is important to preserve the fish products in proper storage condition until further use. Keeping this point in view, fish stick prepared from silver carp (Hypophthalmichthys molitrix) mince by using different kinds of food additives were stored at refrigeration (5 to 8°C) and frozen temperatures (-18 to -20°C) temperature. The results showed that, on “0” day the sensory quality criteria score was 9.00±0.00a for general appearance which decreased to 8.70±0.39a after 3 days of storage at refrigeration temperature and to 8.49±0.41aat frozen temperature after 56 days of storage. The TVBN values were found 22.54±0.17aand 16.04±0.39a, respectively at refrigeration and frozen temperatures which was 7.84±0.95c on “0” day. The peroxide value of the product on “0” day was 6.19 ± 0.71eand the microbial load was 1.49 x104 CFU/g which reached to 19.94 ± 0.17a, 21.58 ± 0.78a meq/kg and 2.13 x107 CFU/g, 1.12 ×102 CFU/g after storage at refrigeration and frozen temperatures. By observing these results present study could be concluded as-frozen temperature storage is comparatively better than refrigeration temperature for storing minced based ‘ready to cook’ products like fish stick and at this temperature the product can be stored for about 8 weeks. Environ. Sci. & Natural Resources, 12(1&2): 175-180, 2019

Production of Biofuel from Cassava

An experiment was conducted to produce ethanol/biofuel from cassava flour which reduce both consumption of crude oil and environmental pollution. Cassava flour hydrolysate with standard glucose and sucrose solutions were used as controls. The effects of yeast concentrations (5, 15 and 20%) and fermentation time (24, 48, 72, 96 and 120 h) on alcohol yield from CFH were also studied. The maximum carbon-dioxide evolved during fermentation was 8.57 g recorded by cassava flour hydrolysate while the conversion efficiency of sugars to alcohol was 247.6, 97.14 and 92.51% for cassava flour hydrolysate, standard glucose and sucrose solutions, respectively. Alcohol produced was mostly ethanol with traces of methanol. However, yeast concentrations did not showed any significant effect but fermentation time had significant impact on alcohol yield which suggests that the high yield of alcohol could be obtained from cassava flour hydrolysate. Environ. Sci. & Natural Resources, 12(1&2): 171-174, 2019

Trend and Variability Analysis of Sunshine Duration in Divisional Headquarters of Bangladesh

In this study, Sunshine duration data of eight divisional headquarters of Bangladesh Meteorological Stations (Dhaka, Rangpur, Rajshahi, Mymensingh, Sylhet, Barishal, Khulna and Chattagram) were analyzed to evaluate the long-term changes and trends. The data used are the BMD data spanning from 1980 to 2010. The annual sunshine duration has decreased by the month of (June –September) from 1980 to 2010. Seasonal changes in sunshine duration were also analyzed where the maximum decline was found in rainy-monsoon season (June – September), the winter season (December – February), then the post-monsoon season (October – November) and the minimum in the pre-monsoon season (March – May). Analysis of observed data before and after 2000 represents the sunshine durations have decreasing trends in all divisional headquarters of Bangladesh except Chattagram station during the month of (January – December). General Circulation Model (GCM) defined that the maximum sunshine hour was decline north-east and south-west in all divisional headquarters of Bangladesh during the month of (June – September) and the minimum sunshine hour was decline in eastern part of the country during the month of (March – May). Environ. Sci. & Natural Resources, 12(1&2): 127-133, 2019

Effectiveness of Some Plant Materials against Jute Yellow Mite on Corchorus Olitorius

An experiment was conducted to evaluate the effectiveness of plant materials against yellow mite (Polyphagotarsonemus latus) on jute (Corchorus olitorius) cv. 0–9897 in both greenhouse and field condition at BJRI during the period from March to October 2016. In greenhouse premises, the highest mortality (69.39, 67.77, 63.86, 62.43 and 61.47%) was recorded in extract of neem seed kernel @ 1:20, mehogony seed, pithraj seed, turmeric powder and green neem leaf, respectively. In field condition, the highest reduction (70.20%) of infestation over control, lowest nodes plant–1 (52.50), tallest plant (3.10 m) and highest yield increased (38.60%) over control were observed in neem seed kernel extract @ 1:20. In conclusion, neem seed kernel extract, mahogany seed extracts, pithraj seed extract, green neem leaf extract and turmeric powder extract @ 1:20 can be safely used by the farmers as components of IPM program of Jute. Environ. Sci. & Natural Resources, 12(1&2): 165-170, 2019

Analyses of Ecological Footprint at Bangladesh Agricultural Research Institute (BARI) Residential Area

Ecological Footprint (EF) assessment helps to identify what activities are having the biggest impact on nature and opens up possibilities to reduce our impact and live within the means of one planet. The introduction of EF has been very necessary for the context of Bangladesh especially in the industrial areas such Gazipur as the endless demand and the unplanned consumption pattern of the population here have been producing a very unsustainable situation. Thus this study intends to initiate it by calculating the Ecological Footprint of Bangladesh Agricultural Research Institute (BARI), one of the important residential area of Gazipur and major consuming areas of that city as a sustainability indicator. Basic equation for assessing EF has been done according to Nunes et al. (2013). EF has been calculated for these components: energy, food, waste and building material consumption. Questionnaire survey has been conducted to gather information about consumption pattern for different components in the households of BARI residential area. The study also identified consumption of natural gas for household purpose as the most contributing factor in the footprint of BARI residential area followed by waste, building materials and electricity consumption. Environ. Sci. & Natural Resources, 12(1&2): 143-149, 2019

Longevity of Bipolaris oryzae on HEERA-2 Hybrid Rice Seed

Seeds of hybrid rice variety Heera-2 was collected from Mymensingh district in Bangladesh. Longevity of Bipolaris oryzae was studied in 2012 to 2016 at Seed Pathology Centre, Bangladesh Agricultural University, Seed processing &preservation center and Seed Pathology Laboratory of Supreme Seed Company Limited. The data collected from the experiments were analyzed for test of significance and compared the treatment means by using DMRT at 5% level of probability following the Statistical tool for Agricultural Research (STAR) 2.1 program.The longevity of B. oryzae was observed till five years by blotter incubation methods, seedling symptom test and growing on test. Both untreated and seeds treated with Vitaflo 200FF (carboxin and thiram) were kept in jute bag and polybag stored for five years under both normal and dehumidified condition. The inocula of B. oryzae on Hybrid Heera 2 seed remained viable up to five years. When the seed samples were stored under dehumidified condition, the highest incidence of B. oryzae was recorded in case of jute bag after five years. After treated with Vitaflo 200FF, there was no any infection of B. oryzae under both storage condition Environ. Sci. & Natural Resources, 12(1&2): 209-213, 2019