Weed flora in the Rift Valley sugarcane plantations of Ethiopia as influenced by soil types and agronomic practises     

YIREFU FIREHUN  TANA TAMADO 《Weed Biology and Management》2006,6(3):139-150

A survey was carried out on 72 sugarcane fields in Wonji-Shoa and Methara sugarcane plantations in the Rift Valley, Ethiopia, to determine the composition and distribution of weeds and to assess the influence of soil types and crop management practises on weed species composition and distribution. A total of 180 weed taxa belonging to 40 families was recorded. Poaceae, Asteraceae, Euphorbiaceae, Fabaceae, and Malvaceae were the most abundant families based on the number of species recorded. Annuals were more common (137 taxa) than perennials (43 taxa). The most frequent and problematic weed species in the plantations, irrespective of the soil types and crop types, were Cyperus spp., Sorghum spp., Euphorbia hirta , Ipomoea cordofana , Rhynchosia malacophylla , Datura stramonium , Launaea cornuta , Portulaca oleracea , and Amaranthus spp., with a frequency of > 65%. Perennial, rhizomatous Cyperus spp. were more dominant in ratoon crops than in plant crops. A partial canonical correspondence analysis (pCCA) showed that soil types, fertilizer application, and crop cycles were the major factors influencing the species distribution in the plantations among all the variables considered in the study. The first pCCA axis structured weed species associated with light-textured soil in contrast to weeds on heavy soil. D. stramonium , Tagetes minuta , and Galinsoga parviflora were mostly associated with light-textured soil, while Xanthium strumarium , Hibiscus trionum , Vigna fischeri , and Ipomoea eriocarpa were mostly associated with heavy-textured soils. The second axis distinguished those species associated with fields receiving fertilizers versus those that were not fertilized. Rottboellia cochinchinensis and Phyllanthus tenellus were mainly associated with fertilized fields while E. hirta and L. cornuta were common on unfertilized fields.  相似文献   

Current and potential geographical distribution of the invasive plant Parthenium hysterophorus (Asteraceae) in eastern and southern Africa     

A J MCCONNACHIE  L W STRATHIE  W MERSIE  L GEBREHIWOT  K ZEWDIE  A ABDUREHIM  B ABRHA  T ARAYA  F ASAREGEW  F ASSEFA  R GEBRE‐TSADIK  L NIGATU  B TADESSE  T TANA 《Weed Research》2011,51(1):71-84

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论技术开发中如何利用农牧民的知识与智慧     

中本和夫  矫江  刘峰  李丽原  塔娜  李宁辉  钱贵霞 《干旱区资源与环境》2017,31(2):14-19

价值链分析法是研究农村开发问题的有效手段。文中通过价值链分析方法构成要素之一的人力资源管理,对技术开发的可能性进行了分析和探讨。经研究证明了根据不具备利害关系的农牧民提出的想法和点子进行技术开发的有效性。以下两种结果是基于农牧民的知识与智慧进行技术开发的成功案例。在黑龙江省盐碱土壤改良中采用了来自水田地区的技术点子。具体内容是通过稻壳防止毛细管作用,种植苜蓿。在内蒙古将牧民的技术点子运用在蔬菜栽培方面。具体内容为利用畜粪发酵热的有机蔬菜种植栽培系统的开发。研究还发现,在构建广域的资源循环系统的过程中对于表现出非协助态度的农牧民,行为经济学的解决方法较有效。研究结果中,有一项有机水稻栽培系统是根据半干旱地区的农牧民提出的技术点子进行设计的,内容为利用羊粪浮力的省力型有机物质投入方法。本研究的研究结论证明了在面对复杂的地域问题研究时,促进包括不具备厉害关系的各地农牧民的参与,及时发现并积极发挥其创意点子的重要性。  相似文献