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31.
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   
32.
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   
33.
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   
34.
Ground-level ozone (O3) pollution is a persis-tent environmental issue that can lead to adverse effects on trees and wood production,thus indicating a need for forestry interventions to mediate O3 effects.We treated hybrid larch (Larix gmelinii var.japonica × L.kaempferi)saplings grown in nutrient-poor soils with 0 or 400 mg L-1 water solutions of the antiozonant ethylenediurea(EDU0,EDU400) and exposed them to ambient O3 (AOZ;08:00-18:00 ≈ 30 nmol mol-1) or elevated O3 (EOZ;08:00-18:00≈ 60 nmol mo1-1) over three growing sea-sons.We found that EDU400 protected saplings against most effects of EOZ,which included extensive visible foliar injury,premature senescence,decreased photosyn-thetic pigment contents and altered balance between pig-ments,suppressed gas exchange and biomass production,and impaired leaf litter decay.While EOZ had limited effects on plant growth (suppressed stem diameter),it decreased the total number of buds per plant,an effect that was not observed in the first growing season.These results indicate that responses to EOZ might have implications to plant competitiveness,in the long term,as a result of decreased potential for vegetative growth.However,when buds were standardized per unit of branches biomass,EOZ significantly increased the number of buds per unit of biomass,suggest-ing a potentially increased investment to bud development,in an effort to enhance growth potential and competitiveness in the next growing season.EDU400 minimized most of these effects of EOZ,significantly enhancing plant health under O3-induced stress.The effect of EDU was attributed mainly to a biochemical mode of action.Therefore,hybrid larch,which is superior to its parents,can be significantly improved by EDU under long-term elevated O3 exposure,providing a perspective for enhancing afforestation practices.  相似文献   
35.
Ecological function of charcoal has been mainly investigated by adding charcoal to soil, which is not fully adequate to understand in situ the role in fire-prone forest ecosystem. To determine in situ effects of charcoal on ecosystem functions, such as nutrient availability, we conducted an experimental burning in a Japanese white birch forest with dense coverage of dwarf bamboo in the understory with or without removal of charcoal. Ammonium-N in the remaining humus layer increased immediately after the burning, but decreased to the level of unburnt plots within 1?month of the burning. Removal of charcoal had no significant effect on the NH4 +-N dynamics. Although burning did not affect NO3 ?-N dynamics during the sampling period, charcoal removal led to a slight increase in NO3 ?-N. The available P increased immediately after the burning, but then fell at 1?month after burning. Charcoal inhibited the available P depletion and prolonged the high availability of P. Greater availability of P might be due to the adsorption of phosphate in charcoal pores. Exchangeable Ca and Mg increased gradually; charcoal appeared to extend the period of higher concentration of exchangeable Ca and Mg. Charcoal deriving from fire is a key factor in influencing available nutrient in the humus layer of post-fire forests.  相似文献   
36.
Pineapple stem starch (PS) was evaluated for its suitability as a new starch source in concentrate for fattening cattle, based on the growth performance, blood profile, and rumen parameters of 36 steers in a 206‐day feeding study. PS was formulated as a 40% concentrate and fed with forage in comparison with ground corn (GC) and ground cassava (CA) formulated at the same level. PS feeding improved weight gain and feed conversion ratio without affecting feed intake. PS did not obviously influence blood lipid profiles throughout the experiment. Ruminal concentration of total short‐chain fatty acids (SCFA) increased with PS without affecting SCFA composition throughout the feeding study. Rumen amylolytic group, especially Ruminococcus bromii, was dominant in the rumen microbial community, and showed increased abundance by PS feeding throughout the experiment. These results clearly indicate the potential of PS as a useful starch source for fattening cattle in terms of rumen fermentation and growth performance.  相似文献   
37.
采用多级采样的方法研究了孟加拉国农村耕作区内棕榈树的传统利用模式和当地的管理经验。农民管理棕榈主要为获取树液产品,生产以糖为主的次生品。树液可直接用作饮料,也可加工成糖蜜或酒精饮料。7块不同地块为棕榈提供生长环境,20.40%的棕榈种植在果园内。尽管中等级的农民拥有多数棕榈(33%),但是主要管理棕榈的是没有土地的农民,他们靠棕榈维持生计。这些农民将自己的智慧应用到棕榈管理当中,从种植到开孔取树液再到产品加工。如果能更科学地管理棕榈,加上农民的智慧,棕榈业将会对当地经济发展起到重要作用,也会丰富当地生物多样性。  相似文献   
38.
Kayama M  Kitaoka S  Wang W  Choi D  Koike T 《Tree physiology》2007,27(11):1585-1593
Growth characteristics of Picea glehnii Masters, P. jezoensis (Sieb. et Zucc) Carr., P. jezoensis var. hondoensis (Mayr) Rehder and P. shirasawae Hayashi from Japan, P. abies (L.) Karst. from Europe and P. glauca Voss, P. mariana Britt., Sterns and Pogg. and P. rubens Sarg. from North America were compared. The trees were grown in similar conditions at the Tomakomai Experimental Forest of Hokkaido University in northern Japan. Tree growth, needle biomass, longevity, photosynthetic rate, nitrogen concentration and specific leaf area (SLA) were measured, and photosynthetic nitrogen-use efficiency was calculated. Picea jezoensis, P. jezoensis var. hondoensis, P. abies and P. glauca had high growth rates, high photosynthetic rates in young needles, high needle nitrogen concentrations and short needle life spans. In contrast, P. glehnii, P. shirasawae, P. mariana and P. rubens had low growth and photosynthetic rates, low needle nitrogen concentrations, long needle life spans and maintained a high photosynthetic nitrogen-use efficiency in older needles. Examination of relationships between several growth parameters of the eight taxa revealed positive correlations between SLA and mass-based photosynthetic rate and between SLA and mass-based nitrogen concentration, whereas mass-based photosynthetic rate and mass-based nitrogen concentration were negatively correlated with needle longevity. The species differed greatly in growth characteristics despite being grown in similar conditions.  相似文献   
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