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This paper presents empirical evidence on the impact of socio-economic factors on the adoption of agroforestry practices in
Cameroon. The analysis uses primary farm-level data collected from June to December 1996. Three major provinces of the country
were covered, namely Centre, Southwest and Northwest Several agroforestry technologies have been promoted among farmers in
the zone, including alley farming, improved fallow, live fencing, cut-and-carry fodder and apiculture. The status of adoption
of each agroforestry practice is described and factors that affect adoption identified. These are gender of farmer, household
family size, level of education, farmer’s experience, membership within farmers’ associations, contact with research and extension,
security of land tenure, agroecological zone, distance of the village from nearest town, village accessibility and income
from livestock. Research findings indicate that since factors affecting farmers’ adoption of agroforestry practices differ
across techniques, generalisation is to be avoided. 相似文献
34.
阐述了现浇楼板混凝土施工时,混凝土终凝前通过二次振捣的施工方法,愈合混凝土内部和表面初裂缝,以提高混凝土密实度,达到控制混凝土裂缝的目的。 相似文献
35.
非洲菊切花保鲜剂的研究 总被引:15,自引:0,他引:15
本文研究由蔗糖、硝酸银、8-HQ(8-羟基喹啉)配制的不同保鲜剂对非洲菊切花插瓶寿命、水分平衡、鲜重变化及观赏值等指标的影响。结果表明:4%蔗糖 200mg/L硝酸银 200mg/L硫酸铝 320mg/L8-HQ的保鲜效果最好。 相似文献
36.
Dimethylaminopropyl methacrylamide (DMAPMA) was grafted onto PET/wool blend fabrics by continuous UV irradiation. Union dyeing
of the photografted fabrics was investigated using three reactive dyes of α-bromoacrylamide reactive groups. The influence of grafting yield, DMAPMA concentration, NaCl amount, pH value, and dyeing
temperature on the dyeability was evaluated. The dyeability of both PET and wool components was improved significantly by
the DMAPMA photografting and successive reactive dyeing. Although the dyeability of the PET component in the blend substantially
was improved with higher grafting, equal dyeability between PET and wool was difficult to achieve due to more facile grafting
and higher reactivity of the wool component compared with the modified PET component. However, the color fastness of the PET/wool
blend fabric was excellent for all three colors. This study may offer a way to achieve union dyeing of PET/wool blend fabrics. 相似文献
37.
Pavarot Noranarttragoon Yuji Ueda Tsutomu Hattori Takashi Matsuishi 《Fisheries Science》2011,77(4):497-502
The yield-per-recruit (YPR) analysis has been used to assess growth overfishing of exploited fish stocks. Since the ex-vessel
price per weight widely depends on the size of the fish, the result of the YPR does not imply the revenue. The value-per-recruit
(VPR) analysis, which is an economic expansion of the YPR analysis, was conducted for bighand thornyhead Sebastolobus macrochir caught off the Pacific coast of northern Honshu, Japan. The results showed that, for the current age at first capture (t
c = 3), the current fishing mortality (F = 0.12) was close to the optimum level. However, for the current F, optimum t
c in the VPR model was 8 years and would lead to a 47% increase compared to the current revenue. The maximum YPR was obtained
at t
c = 6 years, but the revenue at t
c = 6 only gave a 20% increase in the maximum revenue. The difference was caused by the size dependency of the ex-vessel price
per weight. The VPR model would generate fisheries management plans with both economical and biological consideration and
would help in making general consensus of fisheries management strategies. 相似文献
38.
Certain species of thraustochytrids are being explored as potential producer of polyunsaturated fatty acids for nutritional enrichment of food products and use as feed additives in aquaculture. The fatty acid composition and squalene content were determined in the thraustochytrid, Schizochytrium mangrovei that was newly isolated from decaying Kandelia candel leaves in Hong Kong mangrove habitat. The major fatty acid constituents identified in all three S. mangrovei strains were tetradeanoic acid (C14:0), hexadecanoic acid (C16:0), docosapentaenoic acid (C22:5 n-6, DPA) and docosahexaenoic acid (C22:6 n-3, DHA). DHA was the most predominant polyunsaturated fatty acid, and the percentage of DHA (of total fatty acids) in all these strains varied from 32.29 to 39.14%. Only slight changes were observed in fatty acid composition of the S. mangrovei strains harvested at their early (day 3) and late stationary (day 5) phases. In contrast, the cellular squalene content was affected significantly by the culture time; the largest decrease of squalene content from 0.162 mg/g to 0.035 mg/g was found in S. mangrovei FB1 as the culture aged. 相似文献
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