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Nur Muhammed Md. Farhad Hossain Masum Md. Mohitul Hossain Sheeladitya Chakma Gerhard Oesten 《林业研究》2013,24(3):591-597
Homestead forests contribute substantially to the rural economy of Bangladesh. Rural people depend on trees and plants for their energy usage, housing, food and other forms of subsistence livelihood. In order to identify the potential role of forests on homestead dwellers, an empirical field investigation was conducted in the four Upazilas of Mymensingh district of Bangladesh. It was found that land holdings of the respondents within the four sites are the highest in Mymensingh. The study made an important observation that among all homestead vegetation between 5–6 years old, tree species are generally preferred over plants. This is perhaps due to the efforts of the social forestry extension service to demonstrate that planting trees is an important long-term investment. In all four Upazilas, there was a significant correlation between household annual income and homestead forestry, agriculture and fisheries practice, suggesting that higher income families tend to have larger holdings of homesteads, farms and pond areas. Three Upazilas displayed a strong positive relationship (nearly 45%) between homestead forest areas and annual family income; however, the Fulbaria Upazila showed a very poor relationship (0.2%) in this regard. The results of this study suggest that homestead forests play a positive role in the rural economy, in addition to helping mitigate the increasing problem of deforestation in Bangladesh. 相似文献
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Mehrdad Shamsaddini-Bafti Mahnaz Salehi Ali Maghsoudi Ali Mostafa Tehrani Farhad Mirzaei Syed Mojtaba Syed Momen 《畜牧与生物技术杂志(英文版)》2012,3(3):160-165
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05). 相似文献
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Fereydun Nourgholipour Mohammad Mehdi Tehrani Babak Moteshare Zadeh Farhad Moshiri 《Communications in Soil Science and Plant Analysis》2019,50(1):35-48
Production of oilseed crops requires balanced fertilization, while environmental problems of applied fertilizers must be considered. We evaluated seven winter canola cultivars (Brassica napus L.) for their relative efficiency to use or acquire phosphorus (P) under deficient and sufficient conditions. Average root mean diameter (RMD), total root length (RL) and root surface area (RA), of plants were measured as well as rhizosphere properties in rhizobox technique. Water-soluble P (WSP) and phosphatase activity of treatments containing plant were higher than control. WSP increased by 2.86 mg kg?1 soil in Gabriela and 2.63 mg kg?1 soil in Elvis at P deficient condition, compared to the control soil. The Olsen extractable P of the treatments decreased compared to control. Variations in total dry weights of cultivars were mainly explained by the differences in P solubilizing bacteria (PSB) population, pH, and phosphatase activity. The responsible mechanism for the P efficient (PE) cultivars can be higher P uptake through larger root and changes in rhizosphere properties. 相似文献
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Saeed Sanaei Ardakani Mehdi Shorafa Abdolmajid Liaghat Mohsen Farahbakhsh Farhad Dehghani 《Communications in Soil Science and Plant Analysis》2019,50(3):237-253
Disruption in the nitrogen (N) cycle balance has a negative impact on the overall trend of sustainable development, and using soil amendments is necessary to reduce these hazards. This study was carried out as a factorial experiment in a completely randomized design. The treatments consisted of three levels of amendments (0, 7.5 g/kg of pistachio residues, and 7.5 g/kg of biochar) and four levels of irrigation water salinity including 0.5 (urban water), 5.5, 8, and 10.5 dS/m and in three replications. Two pistachio seedlings were transferred to all columns and then in three steps, and in each step, 25 mg N/kg of potassium nitrate was added. The results indicated that pistachio residuals and its biochar increased nitrate outflow from effluent by 9% and 52%, respectively. The effects of amendment treatment and irrigation water salinity on all three characteristics of output nitrate, soil nitrate, and absorbed plant nitrate were significant at 1% level. 相似文献
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Galac S Kool MM Naan EC Daminet S Mol JA Kooistra HS 《Domestic animal endocrinology》2010,39(4):259-267
Studies of human adrenocortical tumors (ATs) causing Cushing's syndrome suggest that hypersecretion of cortisol is caused by altered expression of steroidogenic enzymes and that steroidogenesis can only be maintained when there is expression of the ACTH receptor (ACTH-R). Here we report the screening for the mRNA expression of the ACTH-R, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase, 21-hydroxylase (all in 38 cortisol-secreting ATs), 17α-hydroxylase, and 11β-hydroxylase (both in 28 cortisol-secreting ATs). Real-time PCR (RT-PCR) was applied in all samples and was compared with that in normal canine adrenal glands. Messenger-RNA encoding StAR, steroidogenic enzymes, and ACTH-R were present in both normal adrenal glands and cortisol-secreting ATs. The amounts of mRNA encoding StAR and enzymes of the steroidogenic cluster needed for cortisol production did not differ significantly between either adenomas or carcinomas and normal adrenal glands. The amount of mRNA encoding ACTH-R was significantly lower in carcinomas than in normal adrenal glands (P = 0.008). In conclusion, RT-PCR analysis revealed no overexpression of StAR and steroidogenic enzymes in canine cortisol-secreting ATs. Significant downregulation of ACTH-R in carcinomas might be associated with the malignant character of the AT. 相似文献