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Do Epiphytes in Drier Climates Select Host Tree Substrates between Rough and Smooth Bole Textures and Crown and Stem, Vertical and Upright Stems? What Are the Implications for Water Catchment and Forest Management?
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作者 Chansa Chomba 《Open Journal of Ecology》 2014年第10期641-652,共12页
Epiphyte biomass (dry weight kg) placement between rough and smooth bole bark textures;crown and trunk as well as upright and horizontal substrates in Lusenga National Park were examined through ground surveys. Transe... Epiphyte biomass (dry weight kg) placement between rough and smooth bole bark textures;crown and trunk as well as upright and horizontal substrates in Lusenga National Park were examined through ground surveys. Transects were located at random in woody vegetation using quadrats 20 m × 20 m which were located every 100 m along 1 km long transects. For every host tree substrate sampled, tree species was identified and bark texture was determined. Presence and location of epiphytes were determined through direct observation. Epiphytes were collected, dried and weighed, so as to apportion biomass between rough and smooth bole textures, crown and trunk as well as stem inclination. Rough bole textured stems had more epiphytes of 1967 kg (89%) than smooth bole substrates of 313.48 kg (11%) and also inclined stems had higher biomass of 85% than vertical stems of 14.64% (χ2 = P < 0.005). Trunk had less biomass of 32% and crown had higher biomass of 68% (Mann Whitney U test 0.002 < P < 0.05). It was concluded that epiphytes were more abundant on rough bole textured substrates and in crown than stem. It would appear that rough bole textured substrates provided better physical anchorage and stability against dislodging forces of wind and rain water, hence being suitable for epiphyte establishment and survival. Inclined substrates on the other hand provided a suitable habitat for accumulation of debris and moisture retention, seed settling, germination, and maximum exposure to sunlight all of which support germination and growth of epiphytes. Further research is required to determine successional colonization, incidences of host species specificity, rain water interception and retention and impact of fire on epiphyte biomass as these are important water catchment attributes. 展开更多
关键词 EPIPHYTE Humid Bark Texture rough bole SMOOTH bole Horizontal
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基于灌区运行状况的评价
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作者 李建民 《黑龙江水利科技》 2019年第6期222-225,共4页
文章利用粗糙集理论和集对分析法构建灌区运行状况评价模型,运用博弈论法融合集化了专家评分法与属性重要度法确定的指标权重并得到综合权重,然后对新疆博乐市某大型灌区2017年运行状况运用集对分析法进行综合评价。研究表明:该灌区运... 文章利用粗糙集理论和集对分析法构建灌区运行状况评价模型,运用博弈论法融合集化了专家评分法与属性重要度法确定的指标权重并得到综合权重,然后对新疆博乐市某大型灌区2017年运行状况运用集对分析法进行综合评价。研究表明:该灌区运行状况处于良好水平,在评价分析灌区运行状况时集对分析法能够综合考虑中间数据信息,具有实用性好、分辨率高、评价结果客观、全面等优点,可为全面掌握灌区运行实际情况提供一种有效方法。 展开更多
关键词 集对分析 粗糙集 关联度 灌区运行 博乐市
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