检索结果-南通市图书馆

Acta Geochimica 2016年第3期35卷 294-308页

作者： nasim Ferdous Atikul haque Farazi Department of Geology University of Malaya

Tertiary sandstones collected from southwest Sarawak, Malaysia, were analyzed to decipher their provenance, weathering, and tectonic setting. The studied sandstones have a sublitharenite composition and are dominantly composed quartz with little mica and feldspar, and a small amount of volcanic fragments. These sand- stones were generally derived from quartz-rich recycled orogenic sources. They have relatively high SiO2 content with low na20, CaO, MnO, and MgO contents. Values of Chemical Index of Alteration （CIA） of these rock samples vary from 71 to 93, with an average of 81, implying intense chemical alteration during weathering. A felsic igneous source is suggested by a low concentration of TiO2 com- pared to CIA, enrichment of Light Rare Earth Elements, depletion of Heavy Rare Earth Elements, and negative Eu anomalies. A felsic origin is further supported by a Eu/Eu＊ range of 0.65-0.85 and high Th/Sc, La/Sc, La/Co, and Th/ Co ratios. This work presents the first reported geochemical data of Tertiary sandstones of the Sarawak Basin. These data led us to conclude that the sandstones were dislodged from recycled orogenic sources and deposited in a slowly subsiding rifted basin in a passive continental tectonic setting.

关键词： Geochemistry Tertiary sandstone Provenance Tectonic setting SW Sarawak Malaysia

Effect of land cover on water quality of creek and seepage in mountainous watershed in Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2010年第2期21卷 251-254,I0008页

作者： S.M.Sirajul haque Shyamal Karmakar M.mozaffar Hossain Institute of Forestry and enviromental Science University of Chittagong

The flowing water was collected from very small creeks and seepage water from small dug holes at three different areas,***,Ghagra and Muralipara in Rangamati district of Chittagong Hill Tracts,Bangladesh to investigate the impact of the existing varied land covers on water *** analyses shows that flowing creek water from either mature mixed plantation or young gamar（Gmelina arborea） plantation had significantly（p〈0.05） higher pH value,SO4^2-and Ca^2＋ concentrations,and significantly lower na＋ concentration at Manikchari,compared to natural vegetation and plantation in *** flowing creek water of Ghagra,the concentrations of SO4^2-and K＋,conductivity and total dissolved solids from watershed of 8-year-old teak（Tectona grandis） plantation were significantly higher and the concentrations of HCO3^-,NO3^-and PO4^3-were significantly lower,compared to those of watershed of degraded natural *** Muralipara,flowing creek water from natural vegetation and shifting cultivated land in combination showed significantly higher concentrations of HCO3^-,NO3^-,na＋,K＋,Ca^2＋ and Mg^2＋,and conductivity and total dissolved solids than seepage water as well as tube well water installed in shifting cultivated area alone.

关键词： plantation flowing water shifting cultivation Chittagong Hill Tracts

Clear felling and burning effects on soil nitrogen transforming bacteria and actinomycetes population in Chittagong University campus, Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2012年第1期23卷 123-130页

作者： S.M. Sirajul haque Rahima Ferdoshi Sohag Miah M. Nural Anwar Institute of Forestry and environmental Sciences University of Chittagong Chittagong-4331 Bangladesh Department of Microbiology University of Chittagong Chittagong-4331 Bangladesh

The effect of forests clear felling and associated burning on the population of soil nitrogen transforming bacteria and actinomycetes are reported at three pair sites of Chittagong University campus, Bangla- desh in monsoon tropical climate. Clear felled area or burnt site and 15-21 year mixed plantation of native and exotic species, situated side by side on low hill having Typic Dystrochrepts soil was represented at each pair site. At all the three pair sites, clear felled area or burnt site showed very significantly （p~_0.001） lower population of actinomycetes, Rhizobium, Nitrosomonas, Nitrobacter and ammonifying as well as deni- trifying bacteria compared to their adjacent mixed plantation. From en- vironmental consideration, this finding has implication in managing natural ecosystem.

关键词： Nitrogen transforming bacteria actinomycetes forest clearfelling effects burning effects soil microorganisms Chittagong HillTracts

Shifting cultivation effects on creek water quality around Barkal Upazila in Chittagong Hill Tracts,Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2012年第4期23卷 623-630页

作者： Shyamal Karmakar S.M.Sirajul haque M.Mozaffar Hossain Sohag Miah Institute of Forestry and environmental Sciences University of ChittagongChittagong 4331Bangladesh

Abstract： We report the effects of shifting cultivation on water quality in 16 creeks investigated once in 2007 and twice in 2008 in 16 apparently similar small neighboring watersheds, each of 3 to 5 ha, at four locations around Barkal sub-district under Rangamati District of Chittagong Hill Tracts in Bangladesh. Concentrations of 5042- and K＋, and pH in creek water were lower, and NO3-N and na＋ concentrations were higher in shifting-cultivation land compared to land with either plantation or natu- ral forest or a combination of these cover types. Shifting cultivation effects on some water quality parameters were not significant due to change in land cover of the watershed between two sampling periods either through introduction of planted tree species or naturally regenerated vegetation. Conductivity and concentrations of HCO3- PO43-, Ca2-- and Mg2＋ in creek water showed no definite trend between shifting cultivation and the other land cover types. At one area near the Forest Range Office of Barkal, creek water pH was 5.8 under land cover with a com- bination of shifting cultivation and plantation. At this area na~ concentra- tion in shitting-cultivation land ranged from 32.33 to 33.00 mg-L＂ and in vegetated area from 25.00 to 30.50 mg.L-1 in 2007. At another area, Chaliatali Chara, SO42 concentration in a shifting-cultivation watershed ranged from 4.46 to 10.51 mg-L-1, lower than in a vegetated watershed that ranged from 11.69 to 19.98 mg.L-1 in 2007. S042-concentration in this shifting-cultivation area ranged from 1.28 to 1.37 mg.L^-1 and in the vegetated area from 1.37 to 3.50 mg-L^-1 in 2008.

关键词： Shifting cultivation Creek water quality Chittagong Hill Tracts Riparian vegetation Land cover Bangladesh

Comparative study of some soil properties in forested and deforested areas in Cox’s Bazar and Rangamati Districts, Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2010年第3期21卷 319-322,397页

作者： M.A.Zaman K.T.Osman S.M.Sirajul haque Department of Soil Science University of Chittagong Institute of Forestry and environmental Sciences University of Chittagong

The study dealt with the assessment of impact of deforestation on soil through a comparative analysis of soil physicochemical properties of natural forest and deforested areas. Soil samples from three depths （top, middle and bottom） under natural forest and nearby deforested areas were collected to investigate soil properties. Forest soils show no sig-nificant change in particle size distribution. Bulk density of forested soils shows the significant differences in top and middle layers. Soil pH in top and middle soil, organic matter in top soil and available phosphorus in middle soil of the forest site are found to be significantly higher than that of the deforested soils. Forest soils also have significantly higher level of exchangeable Ca2＋, K＋ in top and middle soil and Mg2＋ at all depth than those of deforested site. Exchangeable na＋ and cation exchange capacity （CEC） are observed unchanged in both sites. The results suggest that change in soil properties was more obvious in surface and sub surface portions of both areas. The study shows that deterioration of physicochemical properties occurred due to deforestation.

关键词： chemical characteristics deforested soil forest soil physical characteristics

Coastal afforestation effects on soil properties at Hatiya in Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2009年第A3期20卷 243-248,287页

作者： K.M.Shaifullah S.M.Sirajul haque M.Sujauddin Shyamal Karmakar Institute of Forestry and environmental Sciences University of Chittagong

An exploratory study was conducted in the coastal plantation (12-and 17-year-old Sonneratia apetala) of Char Alim and Char Piya and on their adjacent barren lands at Char Rehania and Char Nurul Islam in Hatiya of Noakhali district, in Bangladesh to determine afforestation effects on soil properties. At soil depths of 0-10, 10-30 and 30-40 cm across three different land strips viz. inland, middle and sea side in 12-and 17-year-old keora (Sonneratia apetala) plantations, soil moisture, particle density, organic matter and C, total N, pH, available P, K, na, Ca and Mg were significantly (p≤0.05, p≤0.01, p≤0.001) higher, and soil salinity significantly (p≤0.001) lower than that in their adjacent barren lands. Soil moisture, particle density, organic matter and C, total N, pH, soil salinity, available P, K, na, Ca and Mg of surface soil in Char Alim plantation at inland were 31.09%, 2.24 g·cm-3, 2.41%, 4.14%, 0.58%, 7.07, 0.09 dS·cm-1, 28.06 mg·L-1, 0.50 mg·L-1 11.5 mg·L-1, 3.30 mg·L-1 and 2.7 mmol·kg-1, respectively. Their corresponding values for the same depth and land position at adjacent Char Rehania barren land were 16.69%, 1.25g·cm-3, 0.43%, 0.74%, 0.25%, 6.57, 0.13 dS·cm-1, 13.07mg·L-1, 0.30 mg·L-1, 1.4 mg·L-1, 0.30 mmol·kg-1 and 0.50 mg·L-1, respectively. Soil moisture, particle density, organic matter and C, total N, pH, available P, K and Ca decreased, and soil salinity, available na and Mg increased from inland towards sea side in the plantations. Although soil texture did not differ in most soil depths between plantation and adjacent barren land, proportion of sand particle was significantly (p≤0.01) lower and silt particle significantly (p≤0.001) in the plantations higher than that in their adjacent barren lands. In the study, evaluation of all the parameters was also done for the other pair of lands.

关键词： coastal afforestation keora plantation soil physicochemical properties afforestation effect soil texture soil base cations Sonneratia apetala Bangladesh

Water quality of Kaptai reservoir in Chittagong Hill Tracts of Bangladesh

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2011年第1期22卷 87-92页

作者： Shyamal Karmakar S. M. Sirajul haque M. Mozaffar Hossain M. Shafiq Institute of Forestry and environmental Sciences University of Chittagong Chittagong Bangladesh 4331 Department of Soil Science University of Chittagong Chittagong Bangladesh 4331

A study was conducted in Kaptai reservoir, one of the largest man-made freshwater lakes of South-east Asia, to determine present status of water quality and its suitability for fishing and other uses. Water samplings were from middle part of the reservoir at 0.2 and 0.8 fractional depths at five different locations from upstream to downstream viz. Burburichara, Maichchari, Subolong, Basanthakum, and Rangamati. Water analyses show that concentrations of NO3-N, K＋ and total P, and suspended solid at all the sampling stations were beyond the recommended values for fish culture. Concentrations of na^＋, Ca^2＋, Mg^2＋, SO4^2-, Cl^-, total dissolved solid （TDS）, dissolved oxygen （DO） and chemical oxygen demand （COD） were within the standards for aquaculture. Concentrations of NO3-N, SO4^2-, K＋ and total P showed no definite trend with depths, locations as well as rainy and dry seasons. Water pH, conductivity, na^＋ and HCO3- contents were lower in rainy season, and DO and COD higher at almost all the locations in both the depths, compared with dry season. Total solids and concentrations of TDS, DO, COD, Ca^2＋, Mg^2＋ and na^＋ were higher in upstream and decreased gradually towards downstream in the reservoir. Concentrations of DO and Ca2＋ and pH were higher and Mg2＋ less at 0.2-fractional depth than those at 0.8-fractional depth at almost all the locations. The reservoir is in mesotrophic condition containing high concentration of NO3-N and total P, in alarming status with the presence of excessive suspended solids from urban pollution around the town. It is necessary to adopt measures for protecting water quality in the reservoir due to such deteriorations.

关键词： Karnaphuli river lake water quality Chittagong Hill Tract

Insight into 5-aminolevulinic acid-induced modulation of cellular antioxidant metabolism to confer salinity and drought tolerance in maize

在线全文

学校读者我要写书评

暂无评论

BIOCELL 2020年第4期44卷 713-730页

作者： MD.ROBYUL ISLAM TAHIA naZNIN DIPALI RANI GUPTA MD.ASHRAFUL haque MIRZA HASANUZZAMAN MD.MOTIAR ROHMAN Institute of Biotechnology and Genetic engineering(IBGE) Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur1706Bangladesh Department of Genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur1706Bangladesh Department of Agronomy Faculty of AgricultureSher-e-Bangla Agricultural UniversitySher-e-Bangla NagarDhaka1207Bangladesh Molecular Breeding Laboratory Plant Breeding DivisionBangladesh Agricultural Research InstituteGazipur1701Bangladesh

The current study investigated the comparative oxidative damage in twomaize seedlings induced by saline,drought,and combined stress and the ameliorative role of two different doses(20 and 80μM)of 5-aminolevulinic acid(ALA)against the above-mentioned *** grown 10-day-old maize(Zea mays,*** Hybrid Maize-7(BHM-7)and BARI Hybrid Maize-9(BHM-9))seedlings were exposed to 12 dS/m of saline solution,200 mM mannitol-induced drought stress alone and their combined stress for 7 *** revealed that individual stresses retard the plant growth to some degrees,however,their combined stress has more detrimental effects,which might be correlated with lipid peroxidation(MDA)-induced oxidative stress in seedlings,enhanced na+/K+ratio,and augmented generation of superoxide(O_(2)•^(−))and hydrogen peroxide(H_(2)O_(2)).In contrast,exogenous ALA supplementation at 20μM concentration markedly recovered from chlorosis and growth inhibition,substantially scavenged reactive oxygen species(ROS)and MDA by preserving ionhomeostasis and relaxing oxidative stress,also,by boosting catalase(CAT)and glutathione S-transferase(GST),and exclusively via depressing the activity of lipoxygenase(LOX)antioxidant *** the contrary,80μM ALA made things worse,nevertheless,higher activities shown by other antioxidant enzymes,like,superoxide dismutase(SOD),ascorbate peroxidase(APX),peroxidase(POD),and glutathione peroxidase(GPX),which were related to lessen the oxidative damage by highly produced O_(2)•^(−)and H_(2)O_(2) under combined ***-denaturing gel electrophoresis was done for further ***,ALA importantly increased the photosynthetic pigment contents in both genotypes irrespective of ***,GST might have assisted the plants to escape from the herbicidal effect by ***,in the combined stress condition,high ALA concentration may have some positive role to *** findings also showed that BHM-9 performed better than BHM

关键词： Maize Combined stress Salinity Drought 5-aminolevulinic acid Oxidative stress

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

氧在金矿石氰化浸出中的作用

湿法冶金 1993年第4期12卷 25-34页

作者： K.E.haque 张登福

本文简要的评述了氧在金矿石、金精矿等给料氰化浸出中的作用。当金主要以元素状态(Au^0)存在时,其氧化对金在氰化物浸出剂中的溶解是极其重要的。在高pH下,氰化作用对用轻度氧化剂(如空气或氧)氧化Au是有利的。除金的氧化之外,通过向... 详细信息

本文简要的评述了氧在金矿石、金精矿等给料氰化浸出中的作用。当金主要以元素状态(Au^0)存在时,其氧化对金在氰化物浸出剂中的溶解是极其重要的。在高pH下,氰化作用对用轻度氧化剂(如空气或氧)氧化Au是有利的。除金的氧化之外,通过向浸出矿浆中预先通入空气或氧(即预先充氧法)可减轻可溶性硫酸盐、砷酸盐、锑酸盐对金氰化的影响。如果由于金包裹在硫酸盐、硅酸盐、碲化物等矿物中而难处理时,则通氧焙烧或在氧压下浸出,就可使金离析出来。最新的文献资料指出,氰化期间由H_2O_2、na_2O_2、CaO_2或O_3提供的活性氧能显著加速金的氧化-氰化作用,并在非常短的浸出时间内获得较高的金回收率。由本文资料可得出的结论是:在用氰化物浸出剂溶解金的过程中,氧起到极其重要的作用。

关键词：金矿石氰化浸出氧

Threats of Zika virus transmission for Asia and its Hindu-Kush Himalayan region

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2018年第1期7卷 387-393页

作者： Meghnath Dhimal Sushma Dahal Mandira Lamichhane Dhimal Shiva Raj Mishra Khem BKarki Krishna Kumar Aryal Ubydul haque Md Iqbal Kabir Pradeep Guin Azeem Mehmood Butt Harapan Harapan Qi-Yong Liu Cordia Chu Doreen Montag David Alexander Groneberg Basu Dev Pandey Ulrich Kuch Ruth Muller Nepal Health Research Council(NHRC) Ramshah PathKathmanduNepal Institute of Occupational edicine Social Medicine and Environmental MedicineGoethe UniversityFrankfurt am MainGermany Faculty of Social Sciences Goethe UniversityFrankfurt am MainGermany The University of Queensland BrisbaneAustralia Department of Public Health Baldwin Wallace UniversityBereaOhioUSA Department of Epidemiology National Institute of Preventive and Social MedicineMinistry of Health and Family WelfareDhakaBangladesh Public Health Foundation of India GurgaonHaryanaIndia Centre for environmental Health GurgaonHaryanaIndia Translational Genomics Laboratory Department of BiosciencesCOMSATS Institute of Information Technology(CIIT)Islamabad 45550Pakistan Medical Research Unit School of MedicineSyiah Kuala UniversityBanda AcehIndonesia WHO Collaborating Centre for Vector Surveillance and Management SKLIDCCIDICDCChina CDCBeijingChina Centre for environment and Population Health Griffith UniversityNathanQueenslandAustralia Barts and the London School of Medicine Centre for Primary Care and Public HealthQueen Mary University of LondonLondonUK Department of Health Services Ministry of HealthGovernment of NepalKathmanduNepal

Asia and its Hindu Kush Himalayan(HKH)region is particularly vulnerable to environmental change,especially climate and land use changes further influenced by rapid population growth,high level of poverty and unsustainable *** has been a hotspot of dengue fever and chikungunya mainly due to its dense human population,unplanned urbanization and *** an urban cycle,dengue virus(DenV)and chikungunya virus(CHikV)are transmitted by Aedes aegypti and *** mosquitoes which are also competent vectors of Zika virus(ZikV).Over the last decade,DenV and CHikV transmissions by *** have extended to the Himalayan countries of Bhutan and Nepal and ZikV could follow in the footsteps of these viruses in the HKH *** already established distribution of human-biting Aedes mosquito vectors and a naïve population with lack of immunity against ZikV places the HKH region at a higher risk of *** of the countries in the HKH region have already reported ZikV *** have documented an increasing threat of ZikV in Asia and its HKH region because of the high abundance and wide distribution of human-biting mosquito vectors,climate change,poverty,report of indigenous cases in the region,increasing numbers of imported cases and a naïve population with lack of immunity against *** outbreak anywhere is potentially a threat ***,in order to ensure international health security,all efforts to prevent,detect,and respond to ZikV ought to be intensified now in Asia and its HKH *** prepare for possible ZikV outbreaks,Asia and the HKH region can also learn from the success stories and strategies adopted by other regions and countries in preventing ZikV and associated *** future control strategies for DenV,CHikV and ZikV should be considered in tandem with the threat to human well-being that is posed by other emerging and re-emerging vector-borne and zoonotic diseases,and by the continuing urgent need to strengthen public

关键词： Aedes aegypti Aedes albopictus Dengue virus Chikungunya virus Hindu Kush Himalayas Mountain Poverty Zika virus