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11.
M. Parvez Rana Sharif Ahmed Mukul M. Shawkat Islam Sohel Mohammad Shaheed Hossain Chowdhury Sayma Akhter M. Qumruzzaman Chowdhury Masao Koike 《Small-Scale Forestry》2010,9(1):41-51
An exploratory survey was carried out to assess economics and employment generation of the trade of bamboo and bamboo-based
secondary products in the eastern Bangladesh, to obtain reliable information about their status, socio-economic significance,
production and marketing. The study was undertaken over 30 bamboo-based enterprises in a suburban market of eastern Bangladesh,
to investigate regional product details, economic profitability and employment opportunities. The sample entrepreneurs, corresponding
to about 25% of the bamboo enterprise population were interviewed using a semi-structured questionnaire. About 202 full and
part-time workers were employed in the factories, under categories of artisan (who manufactured secondary products). The average number of worker’s in the large, medium and small factories were 9 (artisan
40%), 6.45 (artisan 35%) and 5 (artisan 25%) respectively. The study revealed that there was always a satisfied demand of
skilled artisans. Most of the workers were relatively newly employed (not more than 5 years). The daily wage rate varied between
70 and 130 Tk. ($US 1 equals approximately 70 Bangladeshi Taka (Tk.), as at December 2008). Bambusa balcooa was the most utilized species (39.96%) in terms of monetary value. The price of a single B. balcooa culm in the local market was Tk. 160–210. Nine sizes of articles under seven bamboo categories were identified, these being
bera (36″ × 120″ and 72″ × 96″), bookshelf (36″ × 24″), chaluni (12″ × 12″), chatai (48″ × 60″ and 36″ × 48″), jhuri, rickshaw hood and tukri. Net average profit per article was the highest for rickshaw hoods (Tk. 400 at the retailer stage). The total expected annual
income for an enterprises from all articles types sold was estimated to be Tk. 85,800. Three distinct marketing channels were
identified for selling bamboo and value-added secondary products. The study also generated policy implications for effective
management of bamboo-based enterprises. 相似文献
12.
Because lack of data impedes the assessment of the conservation of medicinal plants, ethno-medicinal studies are important
to fill this gap. This study considered the traditional use of plants for health care by the rural communities in two forested
and non-forested regions of Bangladesh. A total of 230 respondents were interviewed accompanied by field observation and voucher
specimen collection. Altogether, 68 species of medicinal plants belonging to 38 families distributing over 58 genera were
recorded, of which 22 species were common in both regions. Trees were the most commonly utilized growth form and leaves were
the most commonly used plant part. Forests and homesteads were the major sources of medicinal plants in forested and non-forested
regions, respectively. High use versatility (Relative Importance >1) was represented by 14 species; Emblica officinale L. and Allium sativum L. were the most versatile species. Forty-one individual ailments were treated with the medicinal plants recorded. The ailment
categories ‘respiratory problems’ and ‘sexual problems’ received the highest score from the calculation of informants’ consensus
factor (F
ic) in forested and non-forested regions, respectively. The findings could contribute in the pharmaceutical sector by directing
further investigation of bio-active compounds in medicinal plants. Secondly, results could inform the clues for conservation
strategies of forest resources in that region. 相似文献
13.
Traditional systems of medicine have become a topic of global importance recently. Increased commercialization of economically
important medicinal plants has resulted in overharvesting, threatening their survival. The present study was carried out to
document the indigenous uses of medicinal plants by the local communities in and around Rema-Kalenga Wildlife Sanctuary, Bangladesh.
Data collection was predominantly qualitative recording the species use, identifying their relative importance (RI) and assessing
the informants’ consensus factor (Fic) on associated knowledge. We interviewed 140 households of the local community and 5 local herbal practitioners. A total
of 44 plant species were in use to treat 33 ailments under 10 broad disease categories. Five species were found to have high
use versatility (RI > 1), Emblica officinale L. being the most versatile. Respiratory problems scored the highest Fic value (0.56) involving the use of 30% of the species recorded. Terminalia bellerica Roxb., Sterculia villosa Roxb., Dillenia pentagyna Roxb. and Terminalia arjuna Bedd. were being harvested commercially. Use by the community, particularly for subsistence consumption, seemed to be sustainable,
but commercial extraction of some species appeared unsustainable. Buffer zone-based commercial farming of medicinal plants
with a commercial value could serve a dual purpose of assuring sustainable alternative income generation for local communities
as well as conserving the natural resources in protected areas. 相似文献
14.
The aim of this research was to test the hypothesis that exposure to solar radiation increases the checking of wood exposed
to the weather, and to examine the causes and spectral dependency of such an effect. Lodgepole pine decking samples were exposed
outdoors under filters, which blocked selected regions of the solar spectrum while allowing other weathering factors to act
on samples. Surface checking in samples was quantified after 12, 24 and 36 weeks of exposure, and the chemical and micro-structural
changes occurring at weathered wood surfaces were examined. Check numbers and dimensions were greater in samples exposed under
a filter to the full solar spectrum than in samples exposed under filters that blocked the transmission of UV, visible or
infrared radiation. Samples that were shielded from more energetic wavelengths developed less checking and also showed less
delignification at the exposed wood surfaces. Checks developed at the margins of rays and propagated at the interface between
adjacent tracheids, close to the middle lamella. We conclude that exposure to UV and visible light increases the tendency
of wood to check during exterior exposure. Our findings point to a link between changes in cell micro-structure as a result
of photodegradation of lignin and the development of visible checks in wood exposed outdoors. 相似文献
15.
Halder Nirmol Kumar Chowdhury Md. Qumruzzaman Fuentes David Possell Malcolm Merchant Andrew 《Agroforestry Systems》2021,95(8):1429-1443
Agroforestry Systems - Tropical agroforestry practices play a crucial role in mitigating global climate change by absorbing CO2 from the atmosphere through photosynthesis and storing carbon in... 相似文献
16.
17.
The critical S concentration and S requirement of the soil microbial biomass of a granitic regosol was examined. S was applied
at the rate of 0, 5, 10, 20, 30 and 50 μg S as MgSO4·7H2O, together with either 3000 μg glucose-C or 3333 μg cellulose-C, 400 μg N, and 200 μg P g –1 soil and 200 μg K g–1 soil. Microbial biomass, inorganic SO4
2–-S, and CO2 emission were monitored over 30 days during incubation at 25 °C. Both glucose and cellulose decomposition rates responded
positively to the S made available for microbial cell synthesis. The amounts of microbial biomass C and S increased with the
level of applied S up to 10 μg S g–1 soil and 30 μg S g–1 soil in the glucose- and cellulose-amended soil, respectively, and then declined. Incorporated S was found to be concentrated
within the microbial biomass or partially transformed into soil organic matter. The concentration of S in the microbial biomass
was higher in the cellulose- (4.8–14.2 mg g–1) than in the glucose-amended soil (3.7–10.9 mg g–1). The microbial biomass C:S ratio was higher in the glucose- (46–142 : 1) than in the cellulose-amended soil (36–115 : 1).
The critical S concentration in the microbial biomass (defined as that required to achieve 80% of the maximum synthesis of
microbial biomass C) was estimated to be 5.1 mg g–1 in the glucose- and 10.9 mg g–1 in the cellulose-amended soil. The minimum requirement of SO4
2–-S for microbial biomass formation was estimated to be 11 μg S g–1 soil and 21 μg S g–1 soil for glucose- and cellulose-amended soil, respectively. The highest levels of activity of the microbial biomass were
observed at the SO4
2–-S concentrations of 14 μg S g–1 soil and 17 μg S g–1 soil, for the glucose and cellulose amendments, respectively, and were approximately 31–54% higher during glucose than cellulose
decomposition.
Received: 20 October 1999 相似文献
18.
19.
Soumitra Paul Chowdhury 《Soil biology & biochemistry》2010,42(9):1574-6035
Soils are the most important sink for atmospheric hydrogen, which is assumed to be oxidized by abiontic soil hydrogenases or by putative high-affinity hydrogenases of microbial origin. The activity of soil hydrogenases has been found to change with soil temperature as it changes during the day and the season. However, it is unclear whether and to which extent the soil hydrogenases are deactivated by increased temperature. Therefore, we incubated soils from different climates and different ecosystems (forest, agricultural, arid, hyper-arid, paddy, peat) at elevated temperature and measured the residual activity at 25 °C after different incubation times. We found that at least part of the soil hydrogenase is deactivated irreversibly already at relatively low temperatures (>30 °C) and short exposure times (>10 min) and that the deactivation was more pronounced in soil from cold versus hot climate. The deactivation kinetics could be fitted to a biexponential model, but were complex with respect to soil type and deactivation temperature. The results show that new hydrogenase activity has to be generated in the soil to compensate for activity loss by diurnal and seasonally increased temperature. 相似文献
20.
Fluorescence of dietary porphyrins as a basis for real-time detection of fecal contamination on meat
Ashby KD Wen J Chowdhury P Casey TA Rasmussen MA Petrich JW 《Journal of agricultural and food chemistry》2003,51(11):3502-3507
Digestion of green plants in the gastrointestinal (GI) tract produces degradation products from chlorophyll that cause ingesta and feces to be highly fluorescent. This property was exploited for development and construction of instruments to noninvasively detect minute quantities of feces on meat samples in real time. The presence of feces on meat products is a primary source of foodborne pathogens, such as Escherichia coli O157:H7 and Salmonella. This new technology provides a rapid and accurate alternative to the practice of visual inspection and augments more time-consuming biological testing methods. This innovation can assist meat processors and government inspectors in their efforts to provide safe and wholesome food to consumers. 相似文献