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M. Lemenih K. F. Wiersum T. Woldeamanuel F. Bongers 《Land Degradation \u0026amp; Development》2014,25(2):130-142
Although the human domestication of forest and tree resources is often considered to result in resource degradation, it may also lead to improved resource potentials. This paper assesses the nature and dynamics of gum and resin focused woodland exploitation and management systems in Ethiopia in the context of degradation and domestication processes. In three sites with commercial gum resin producing woodlands and production history, we studied variation in (i) woodland management and gum resin production systems and (ii) socio‐economic and biophysical factors that condition the management and production systems. On the basis of their organizational features, we formulated nine production models and related them to different phases of domestication and different degrees of ecosystem degradation. The production systems gradually evolved from the extraction of wild trees to production in an adapted forest system. However, domesticated woodlands with an adapted forest structure and composition and increased provisioning services are still little developed despite decades of production history. Many of these woodlands are undergoing serious degradation because of low quality management practices. This is mainly attributable to existing land use practices and the social arrangements for the production of and trade in the gums and resins. The findings illustrate that domestication involves not only a change in ecological and production systems but also the development of social arrangements for production and trade. We conclude that the status of domestication in a social sense determines whether forests and/or specific forest resources are degraded or aggraded in the sense of resource enrichment. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Alemayehu Hido Motuma Tolera Paul H. Evangelista 《Journal of Sustainable Forestry》2020,39(6):620-634
ABSTRACT A study was conducted in South Omo Zone, Ethiopia with the aim of assessing the population status of the frankincense tree Boswellia neglecta and investigating its resin essential oil chemical composition. The status of populations of B. neglecta was assessed by examining the density, abundance, frequency, dominance, importance value index, and population structure. Resin sample was analyzed for the physicochemical properties. The composition of the essential oil was analyzed with Gas Chromatography-Mass Spectrometry. The high values of density, abundance, frequency, dominance, and importance value index for B. neglecta showed the potential of the tree for bulk resin collection. Boswellia neglecta had a bell-shaped diameter distribution indicating a hampered regeneration. The B. neglecta resin had a moisture content of 2.68%, ash content of 0.99%, pH of 5.7, and oil yield of 5.92%. The resin possessed good quality as compared to resins in other reports. The essential oil was optically active (?31.6° at 23.2°C). The essential oil contained several compounds, but 71.1% of the composition were formed mainly from methyl oleate, methyl linoleate, methyl palmitate, which have not been reported from B. neglecta. Sustainable management must be enacted since the agro-pastoralist mode of life hinders regeneration of the species and its resin resources. 相似文献
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目的 探讨大黄素、虎杖苷、乳香挥发油配伍对非肥胖性糖尿(non-obese diabetic,NOD)小鼠慢性非细菌性前列腺炎发挥治疗作用的最佳配比。方法 正常雄性NOD小鼠220只,按照L8(27)正交表随机分为8组,另设立阳性对照组、模型组、空白对照组,共11组,每组20只。按组别给予相应干预,酶联免疫吸附法(enzyme-labeled immunosorbent assay,ELISA)检测NOD小鼠前列腺组织匀浆中肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白介素-1β(interleukin-1β,IL-1β)、白介素-6(interleukin-6,IL-6)、白介素-10(interleukin-10,IL-10)含量的变化,并结合苏木素-伊红(haematoxylin-eosin,HE)染色法评价前列腺组织病理改变程度,明确大黄素、虎杖苷、乳香挥发油的最佳配比与量效关系。结果 正交实验极差结果显示各因素影响强弱依次为虎杖苷 > 大黄素 > 乳香挥发油,方差分析结果发现虎杖苷、大黄素、乳香挥发油对疗效的影响具有统计学意义(P<0.01,P<0.05)。大黄素、虎杖苷、乳香挥发油的最佳配比为大黄素0.1 g/kg、虎杖苷0.4 g/kg、乳香挥发油0.4 g/kg。结论 大黄素、虎杖苷、乳香挥发油的最优比例配伍具有减轻慢性非细菌性前列腺炎动物模型炎症的疗效,乳香挥发油与虎杖苷之间具有协同作用。 相似文献
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