Ecological aspects of heavy metals in sediments of padma river in Bangladesh

ABSTRACT
The study was piloted to assess the ecological risk of heavy metals in sediments collected from the Padma River in Bangladesh during April to July 2022. The sediment samples were collected from five sampling sites and analyzed in the laboratory of the Soils Science, Dept. of Soil Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University using ICP-MS. The mean concentration of As, Cd, Cr, Cu, Pb and Zn in summer season were 0.59, 0.83, 7.10, 16.23, 5.53 and 44.60 mg/kg, respectively. In winter, the mean concentration of As, Cd, Cr, Cu, Pb and Zn are 1.59, 1.22, 10.37, 24.43, 8.07 and 66.97mg/kg, respectively. Metals concentrations were found below the recommended value set by different sediment quality guidelines except for Cd. Multivariate analysis demonstrated that the vast majority of the metals in agricultural sediments may originate from both anthropogenic and lithogenic activities. The contamination factor (CF), geo-accumulation index (Igeo) and potential ecological risk (PER) revealed that most of the soil samples were contaminated by Cd. The geo-accumulation index values showed that most of the samples were poorly contaminated by heavy metals. Sediment sampling sites showed low to moderate potential ecological risk (PER) in the context of PER. The results also described that the pollution load index (PLI) for all investigated samples were lower than the standard level but the growing number of industries may cause advanced
declinations of sediments. However, regular monitoring is needed for the documentation of any alternation in the quality of sediments and minimizes the damage to the benthic ecosystem.
Key words: Heavy metal, Sediments, Spatial distribution, Ecological Risk, Padma River

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Effect of ZN and B application on mustard at madhupur soil under aez 28

ABSTRACT

Mustard (Binasarisha-9) was evaluated against four Zn levels (0, 3, 6, 9 kg Zn ha-1) and three B levels (0, 2, 4 B ha-1) at Madhupur under AEZ 28. The results revealed that there was a significant improvement in the growth and seed yield with increasing level of B and lower Zn levels, respectively. The highest B level        (4 kg ha-1) and lower Zn level (3 kg ha-1)  resulted 96 cm plant height, 5.33 branches plant-1, 86.33 siliqua plant-1, 7.33 cm siliqua length, 28.33 seed siliqua-1 and 1633.30 kg seed ha-1. It is suggested that for achieving higher seed yields in mustard, the Zn application may be done at the rate of 3 kg ha-1 and with B of 4 kg ha-1.

Key words: Boron, Zinc, yield and mustard 

Introduction: The soil of Bangladesh has wide variation and complexity due to diverse nature of physiography, parent materials, land type, drainage conditions and agro ecology. Depending on these aspects, the country has been divided into 30 agro ecological zones (AEZ), which varied greatly in respect of area, land and soil, climate, and cropping intensity (FAO-UNDP, 1988). Some AEZs are very potential for crop agriculture and nutrient supplying capacity but some are being depleted due to intensive cropping. Madhupur Tract (AEZ 28) is one of them. The present study was concentrated to this AEZ which is a region of complex relief and soils are developed over the Madhupur clay. The landscape comprises of level upland, closely or broadly dissected terraces associated with shallow to broad deep valleys. Eleven general soil types exist in the area of which Deep Red Brown Terrace, Deep Red Brown Terrace soils and Acid Basin Clays are the major ones. The soils on the terrace are better drained, friable clay loams to clay overlying friable clay substratum at varying depths. Soils in the valleys are dark grey heavy clays. The top soils are mainly very strongly acidic in reaction but ranges up to slightly acidic with low to medium status of organic matter, low moisture holding capacity and low fertility level. The soils are mainly phosphate fixing low to medium in P, B and K; and medium to optimum in S content. The major land type comprises 56% highland and 18% medium highland (FRG, 2018). Texturally the soils are loam and sandy loam. Over the last 2-3 decades, enormous pressure has been exerted on the soil resource to produce more food for its population. Intensification of agricultural land use has increased remarkably and the cropping intensity has increased from 143% in 1971-72 to about 197% in 2016-2017 (Krishi Diary, 2021). In addition, cultivation of high yielding varieties for all crops has increased remarkably. Consequently, this has resulted in deterioration of soil fertility with emergence of micronutrient deficiency. In this country, chronologically N, P, K, S, Zn and B deficiencies have appeared in soils and crops of Bangladesh (Islam, 2008). Among the micronutrients, next to zinc, boron deficiency is prominent in soils of Dinajpur, Rangpur, Bogra, Sirajganj, Mymensingh, Comilla and Sylhet district (SRDI, 2010). The use of chemical fertilizers as the supplemental source has been increasing steadily but these are not applied in balanced proportion. Of the total fertilizer used in the country, urea alone constituted about 75% (FRG, 2012). Previous study indicated that about 60% cultivable land of Bangladesh is deficient in N, P and K (Miah et al., 2008). Moreover, organic matter content in country’s soils is low, the majority being below the thresh hold level (1.5%) and it was gradually depleted by 5 to 36% during the period of 1967-1995 (Ali et al., 1997). Islam (2008) mentioned that organic matter content in Bangladesh soils is generally around 1% in most and around 2% in few soils.

Pre and post-harvest soil nutrient status at rangpur sadar sugarcane field

ABSTRACT
An experiment was conducted at the farmer’s field at the Rangpur, during January-December 2018 to evaluate the nutrient status of pre and post-harvest soil of the sugarcane field. The experiments consisted of seven treatments viz., T0 = Control (No fertilizer), T1 = N165P55K120S30Zn2.5Mg20 (as per soil analysis), T2 = T1 + Dolomite (1 t ha-1),T3 = 50% of T1 + Poultry manure (10 t ha-1), T4 = 50% of T1 + Poultry manure (10 t ha-1) + Dolomite (1 t ha-1), T5 = 50% of T1 + Cowdung (12.5 t ha-1) and T6 = 50% of T1 + Cowdung (12.5 t ha-1) + Dolomite (1 t ha-1). Results revealed that all the treatments showed statistically more or less similar to each other in respect to pH (5.51-5.71), OM (1.70-1.88),Ca (3.00-3.82 me 100 g-1) and Zn (0.93 to 1.07 μg g-1) contents of the post-harvest soil. Total N contents were the highest in T5 (0.124%) followed by T4 (0.105%) while it was the lowest (0.085%) in T6.However, the highest available P, S, and Ca were found in those post harvest soil at Rangpur which treatment T5.
Key words: Sugarcane, initial soil, post-harvest soil.

Investigation of biodiversity status in accordance of simpson’s diversity index and its conservation strategy at Ramsagar national park in Dinajpur district of Bangladesh

ABSTRACT
The present study was designed to assess the biodiversity status at Ramsagar National Park (RNP) inDinajpur district, Bangladesh period from June 2019 to August 2020. Data on the diversity of the floral andfaunal species were gathered using the KII and FGD by forest-responsible persons especially bit officer andforest rangers. A total of 100 residents of the research area participated in a questionnaire survey to performthe study. The study’s findings revealed that 10.09% of climber species, 31.95% of herbs, 13.45.1% of shrubspecies, and 44.51% of tree species made up the total floral diversity. According to the study, RamsagarNational Park’s strong floral variety status was reflected by the Simpson’s diversity index value of 0.97. On
the other hand, 74.23% aves, 13.78% amphibians, 5.31% reptiles, 6.68% mammals and cultivated differenttypes of fish speciesin the aquatic body were found in Park. According to the result of Simpson’s diversityindex, the status of the faunal diversity is very rich and diverse which was 0.93. In the park, there werevarious barriers to the conservation of biodiversity and the growth of ecotourism viz. poor planning andmanagement, disregard for management authority, etc. The report recommended that the responsiblegovernment authority quickly take necessary action to increase staffing, obtain strongauthorization, includethe media, execute policies and regulations for conserving its biodiversity.
Key words: Biodiversity, conservation, simpsons’ index, eco-tourism, park

Influences of different plant spacing and application times of growth regulator (mepiquat chloride) on the internode length of cotton-

ABSTRACT

An experiment was conducted at Cotton Seed Multiplication, Training and Research Farm, Sreepur, Bangladesh during 2016-2018 to evaluate the response of cotton plant height to different plant spacing, concentration as well as time of application of mepiquat chloride (MC) as growth regulator. Plant spacing were  like 45 cm × 30 cm, 60 cm × 20 cm, 60 cm × 30 cm, 60 cm × 40 cm, 75 cm × 30 cm, 75 cm × 40 cm, 90 cm × 10 cm and 90 cm × 45 cm; MC was sprayed @ 1.0 ml L-1 water at 25, 50, 75, 100 and 125 days after emergence (DAE) in 2016 whereas  @ 1.0, 2.0, 3.0 and 4.0 ml  L-1  water at 25, 50 and 75 DAE for each conc. in 2017. During 2008 MC sprayed @ 2.0 and 4.0 ml L-1 water at 25 DAE, 2.0 and 4.0 ml L-1 water  at 50 DAE,  2.0 ml L-1 water  at 25 as well as 50 DAE in 2018 along with water sprayed  as control. The shortest internodes (3.00 cm) was obtained from 1ml MC L-1 water at 25 DAE with medium plant spacing 60 cm ×   30 cm and the longest (6.67) was from water treatment with 90 cm × 45 cm spacing. So, cotton cultivation in Sreepur, Gazipur areas may be accelerated with foliar application of mepiquat chloride @ 1 ml L-1 water at 25 DAE along with plant spacing of 60 cm x 30 cm for higher yield and quality.

Key words: MC, spacings, foliar application, internode length

Genetic diversity analysis for different agro-morphological characters of tossa jute

ABSTRACT

The genetic diversity was studied for eleven growth and yield related characters in fifty three genotypes of tossa jute which were collected from the Gene Bank of Bangladesh Jute Research Institute (BJRI), Dhaka. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. The highest intra-cluster distance was estimated for cluster IV (0.338) which consisted of fourteen genotypes followed by cluster III (0.330) for eighteen genotypes, cluster V (0.297for seven genotypes and cluster II (0.284) for eleven genotypes. Cluster III contained the largest number of genotypes (eighteen) followed by cluster IV (fourteen) and cluster II (eleven), respectively. The inter cluster distance was maximum between cluster I and V (20.616) followed by the distance between clusters I and IV (18.405), I and III (14.857), II and V (10.984), I and II (10.277) indicating that the genotypes grouped within these cluster were highly divergent from each other. The least genetic distance at inter-cluster level was observed between cluster IV and V (2.871), followed by the distance between clusters III and IV (4.296), and between II and III (4.584) indicating that the genotypes of these clusters were genetically closely related. The maximum contribution was paid by the character, base diameter (0.5335) followed by green wt. without leaves (0.4790), green bark thickness (0.4672) and plant height (0.3858).

Key words: Genetic diversity, clustering, tossa jute.

Introduction

 Information on genetic divergence among the parental materials is vital to plant breeder for an efficient choice of parents for hybridization. More diverse parents are the chances for high heterotic F1S and broad spectrum of variability in segregating generation (Murty and Arunachalam, 1966). However, evaluation of genetic diversity is important to know the source of gene for a particular trait within the available germplasm (Tomooka, 1991). In the past, very few researches have been carried out related to morpho–agronomic diversity and relationships in jute with diverse geographical origins. Plave and Sinha (2005) used 6 accessions of C. capsularis L. and 7 accessions of C. olitorius L. for their study. Recently, Benor et al. (2012) used only C. olitorius L. species to study genetic diversity and relationships inferred from molecular and morphological data. Moreover, multivariate methods particularly principal component analysis (PCA) have proven to be useful for characterizing, evaluating and classifying germplasm when a large number of accessions are assessed for several characteristics of agronomic importance (Badenes et al., 2000). Rapid genetic improvement of crop depends on the availability of sufficient genetic diversity, which could be selected and combined in various forms to produce reasonable improvement (Wani, 2011). Hence in the present study the genetic diversity was studied for eleven growth and yield related characters in fifty three genotypes for further development and creation of higher diversity in tossa jute.