Soil Properties in Two Forest Sites in Cox's Bazar, Bangladesh

Akhtaruzzaman, Md.,Osman, K.T.,Sirajul Haque, S.M. Institute of Forest Science 2015 Journal of Forest Science Vol.31 No.4

Soil samples were collected from three depths (0-10 cm, 10-40 cm and 40-80 cm) of two forest sites including one plantation dominated by teak with some other minor species and another degraded natural forest in Cox's Bazar, Bangladesh to compare their soil properties. Some vegetation parameters were also studied. For this study $10{\times}10\;m$ and $2{\times}2\;m$ quadrats were used for the tree and undergrowth parameters, respectively. Soil samples were also collected from these quadrats. Between the two forest types, the highest levels of organic carbon, total nitrogen, available phosphorus, exchangeable bases and cation exchange capacity (CEC) were found in soils of the plantation. The soils were acidic in nature and exchangeable Al concentrations were low. Teak dominated forest plantation had higher soil fertility index (SFI) than the degraded natural forest site. Steps for reforestation and appropriate protection are needed to improve the situation.

Evaluation of Drying Performance, Energy Consumption, and Quality of Two-Stage Dried Maize Grain

Akhtaruzzaman Md.,Mondal Md. Hasan Tarek,Biswas Mrityunjoy,Sheikh Md. Abdul Momin,Khatun Anwara Akter,Sarker Md. Sazzat Hossain 한국농업기계학회 2021 바이오시스템공학 Vol.46 No.2

Purpose In this paper, the effect of two options (first option: fluidized bed drying (120–160 °C) + sun drying; second option: fluidized bed drying (120–160 °C) + again fluidized bed drying (65 ± 2 °C)) of two-stage drying on kinetics, energy consumption, quality of dried maize as color, nutritional properties, and hardness was evaluated to assess the drying performance. Methods First stage drying for both options was executed by FBD at 7.0 cm bed thickness within the temperature range of 120– 160 °C for 1.5–4 min. Then, the samples were tempered for 45 min in a closed container after completion of first stage drying. Second stage drying was then done by sun drying method (temperature: 33–36°C, RH: 52–65%, air velocity 0.4–0.6 m/s) for first option while for second option, it was accomplished again by FBD (65 ± 2°C). Results Drying time was shorter in the case of second option (2.23 h) than first option (4.98 h). Effective moisture diffusivity was found higher in both options of two-stage drying (10.5 × 10−09 m2/s to 63 × 10−09 m2/s) than control drying. Specific energy consumption was lower in first option compared to second option. Color of dried maize in two-stage options deteriorated markedly. However, nutritional qualities of dried grain for two-stage drying technique were similar to control sample. Hardness of the two-stage dried maize was lesser than control product. Conclusion The two-stage drying options of maize drying instead of conventional sun drying method can be considered an alternative drying technique for the commercial maize drying industries.

Properties of Soils under Different Land Uses in Chittagong Region, Bangladesh

Akhtaruzzaman, Md.,Osman, K.T.,Sirajul Haque, S.M. Institute of Forest Science 2015 Journal of Forest Science Vol.31 No.1

In this study, we investigated the effects of three land uses on soil properties in two soil layers; surface soil (0~15 cm) and subsoil (15~30 cm). Soil samples were collected from planted forest, barren lands and cultivated lands from different areas in Chittagong Cox's Bazar and analyzed for some physical and chemical properties. Results showed that soil textural class varied from sandy clay loam in planted forest and barren land site to sandy loam in cultivated soils. Maximum water holding capacity was higher in forest followed by barren land and the lowest in cultivated lands. At both soil depths, soils of cultivated land showed the highest values of bulk density (1.42 to $1.50g\;cm^{-3}$), followed by barren lands (1.37 to $1.46g\;cm^{-3}$) and the least (1.32 to $1.45g\;cm^{-3}$) in forest soils. Total porosity decreased with depth ranging from 40.24% to 41.53% in subsoils and from 42.04 to 43.23% in surface soil of cultivated and of planted forest sites respectively. The result further revealed that organic carbon (OC) and total nitrogen (TN) contents were higher in the planted forest soil than in other two land uses. The soils of all land uses under study are acidic in nature and the lowest pH was found in both surface and subsoils of barren land. Cultivated soil contained the highest amount of available P, Ca, Mg and K in both surface soil and subsoils. In contrast, barren site had the lowest contents of available P, Ca, Mg and K in both layers. The soil organic carbon (SOC) and total N storage were higher in planted forest than in barren and cultivated land uses.

Extractable Micronutrients in Soils of Some Forested and Deforested Sites of South Eastern Hilly Areas of Bangladesh

Akhtaruzzaman, Md.,Osman, K.T.,Haque, S.M. Sirajul Institute of Forest Science 2018 Journal of Forest Science Vol.34 No.6

Extractable iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) contents and their distribution with depths in soils of forested and adjacent deforested areas at Jahazpura, Teknaf, Cox's Bazar of Bangladesh were studied. The soils under forest showed higher levels of DTPA-extractable micronutrients in all three layers of soil in comparison to those of the deforested areas. The differences between forested and deforested sites were, in most cases, significant.. The top soils of forested sites had the higher contents of micronutrient and generally decreased with depth in forested soils, while there was no regular trend of distribution in deforested soils. The study also revealed that contents of extractable Fe, Mn and Cu were sufficient in all depths and sites but Zn was deficient in bottom layer of forested and all three layers of deforested sites. The results suggested that organic matter, clay and soil pH could play important roles in concentrations and distributions of micronutrients in soils of the study areas.

Some DTPA Extractable Micronutrients in Different Hill Forest Soils of Chittagong Region, Bangladesh

Akhtaruzzaman, Md.,Osman, K.T.,Sirajul Haque, S.M. Institute of Forest Science 2016 Journal of Forest Science Vol.32 No.1

DTPA (Diethelene-triamine pentaacetic acid) extractable micronutrients of surface soil samples from six different locations of Cox's Bazar and Chittagong districts were studied. All the soils under study were sufficient in DTPA extractable Fe, Mn and Cu contents. The available Zn contents in soils of Dulhazara, Chengchhari and Faissakhali under study were also above the critical limit while soils at Fulchhari, Hasnabad and CU were deficient in available Zn. The study also showed that DTPA extractable Fe content had the significant and positive relationships with clay and soil organic carbon. On the hand, negative and significant relationship was observed between extractable Mn and soil pH while DTPA extractable Zn and Cu were positively and significantly correlated with soil organic carbon of the studied area.

Properties of Soils under Different Land Uses in Chittagong Region, Bangladesh

Md. Akhtaruzzaman,K.T. Osman,S. M. Sirajul Haque 강원대학교 산림과학연구소 2015 Journal of Forest Science Vol.31 No.1

In this study, we investigated the effects of three land uses on soil properties in two soil layers; surface soil (0∼15 cm) and subsoil (15∼30 cm). Soil samples were collected from planted forest, barren lands and cultivated lands from different areas in Chittagong Cox’s Bazar and analyzed for some physical and chemical properties. Results showed that soil textural class varied from sandy clay loam in planted forest and barren land site to sandy loam in cultivated soils. Maximum water holding capacity was higher in forest followed by barren land and the lowest in cultivated lands. At both soil depths, soils of cultivated land showed the highest values of bulk density (1.42 to 1.50 g cm-3), followed by barren lands (1.37 to 1.46 g cm-3) and the least (1.32 to 1.45 g cm-3) in forest soils. Total porosity decreased with depth ranging from 40.24% to 41.53% in subsoils and from 42.04 to 43.23% in surface soil of cultivated and of planted forest sites respectively. The result further revealed that organic carbon (OC) and total nitrogen (TN) contents were higher in the planted forest soil than in other two land uses. The soils of all land uses under study are acidic in nature and the lowest pH was found in both surface and subsoils of barren land. Cultivated soil contained the highest amount of available P, Ca, Mg and K in both surface soil and subsoils. In contrast, barren site had the lowest contents of available P, Ca, Mg and K in both layers. The soil organic carbon (SOC) and total N storage were higher in planted forest than in barren and cultivated land uses.

Evolution of Humanoid Robot and Contribution of Various Countries in Advancing the Research and Development of the Platform

Md. Akhtaruzzaman,A. A. Shafie 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

A human like autonomous robot which is capable to adapt itself with the changing of its environment and continue to reach its goal is considered as Humanoid Robot. These characteristics differs the Android from the other kind of robots. In recent years there has been much progress in the development of Humanoid and still there are a lot of scopes in this field. A number of research groups are interested in this area and trying to design and develop a various platforms of Humanoid based on mechanical and biological concept. Many researchers focus on the designing of lower torso to make the Robot navigating as like as a normal human being do. Designing the lower torso which includes west, hip, knee, ankle and toe, is the more complex and more challenging task. Upper torso design is another complex but interesting task that includes the design of arms and neck. Analysis of walking gait, optimal control of multiple motors or other actuators, controlling the Degree of Freedom (DOF), adaptability control and intelligence are also the challenging tasks to make a Humanoid to behave like a human. Basically research on this field combines a variety of disciplines which make it more thought-provoking area in Mechatronics Engineering. In this paper a various platforms for Humanoid Robot development are identified and described based on the evolutionary research on robotics. The paper also depicts a virtual map of humanoid platform development from the ancient time to present time. It is very important and effective to analyze the development phases of androids because of its Business, Educational and Research value. Basic comparisons between the different designs of Humanoid Structures are also analyzed in this paper.

Globalization, Financial Liberalization and the Behavior of the Long Run Money Demand in the Bangladesh Economy

MD. Akhtaruzzaman 한국국제경제학회 2007 International Economic Journal Vol.21 No.3

The paper estimates the long run demand for money function in Bangladesh economy using co-integration and Vector Error Correction Modeling (VECM) technique. The co-integration results suggest that though the process of globalization has shown still no significant impact on money demand by the fact that the foreign interest rate is seen statistically not significant, the financial liberalization has important impact reflected in the statistically significant role of domestic interest rate in influencing both M1 and M2 money demand. Estimate of VECMs also reveals the fact that the short run speed of adjustment is moderately influenced by the financial reform measures to establish the long run relation between money balances, income and domestic interest rates. The phenomenon of credit constraint in the context of a developing country has shown no significant role in influencing money demand which may imply that the stage of financial development is getting higher level in the Economy of Bangladesh. The existence of exchange rate depreciation in co-integration relation with expected sign suggests that currency substitution is now effective in the monetary sector and therefore, its impact should be considered effectively in the monetary policy matrix of Bangladesh.

Soil Properties Under Different Vegetation Types in Chittagong University Campus, Bangladesh

Md. Akhtaruzzaman,Sajal Roy,Muhammad Sher Mahmud,T. Shormin 강원대학교 산림과학연구소 2020 Journal of Forest Science Vol.36 No.2

Soil physical and chemical properties at three layers such as top (0-10 cm), middle (10-20 cm) and bottom (20-30 cm) layers under three different vegetation types were studied. Soil samples were collected from Acacia forest, vegetable and fallow lands of Chittagong university campus, Chittagong, Bangladesh. Results showed that sand was the dominant soil particle followed by clay and silt fractions in all soil depths under different vegetation types. Soils of fallow land showed the highest values of bulk density while forest soils had the lowest values at three depths. Acacia forest soil having lowest values of dispersion ratio (DR) is less vulnerable while fallow soil with highest DR values is more vulnerable to soil erosion. The lower pH value at all soil layers in three ecosystems represented that soils under study are acidic in nature. Contents of organic matter, total nitrogen, exchangeable cations (Ca2+, Mg2+, K+ and Na+) and cation exchange capacity (CEC) were observed higher in Acacia forest soils compared to vegetable and fallow soils. Only soils of vegetable land had higher level of available phosphorus in three layers than that of other two land covers. The study also revealed that different soil properties were observed in three different vegetation types might be due to variation in vegetation and agronomic practices.

Soil Properties in Two Forest Sites in Cox’s Bazar, Bangladesh

Md. Akhtaruzzaman,K. T. Osman,S. M. Sirajul Haque 강원대학교 산림과학연구소 2015 Journal of Forest Science Vol.31 No.4

Soil samples were collected from three depths (0-10 cm, 10-40 cm and 40-80 cm) of two forest sites including one plantation dominated by teak with some other minor species and another degraded natural forest in Cox's Bazar, Bangladesh to compare their soil properties. Some vegetation parameters were also studied. For this study 10x10 m and 2×2 m quadrats were used for the tree and undergrowth parameters, respectively. Soil samples were also collected from these quadrats. Between the two forest types, the highest levels of organic carbon, total nitrogen, available phosphorus, exchangeable bases and cation exchange capacity (CEC) were found in soils of the plantation. The soils were acidic in nature and exchangeable Al concentrations were low. Teak dominated forest plantation had higher soil fertility index (SFI) than the degraded natural forest site. Steps for reforestation and appropriate protection are needed to improve the situation.