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1.
Mengsteab Hailemariam Emiru Birhane Zebene Asfaw Solomon Zewdie 《Agroforestry Systems》2013,87(6):1261-1272
Tree species in agroforestry are important source of inoculum for companion agricultural crops. Agroforestry trees can serve as a source of Arbuscular mycorrhiza (AM) inoculants to intercropped annuals. We studied spore abundance, root colonization of Albizia gummifera (J.F. Gmel.) and Croton macrostachyus (Hochst Ex Del.) trees and their effect on colonization of maize. Soil and root samples were collected from field standing trees from under and outside the canopy of trees and maize crops in the main rainy season. The number of spore count was significantly higher under the canopy of A. gummifera (791/100 g of dry soil) and C. macrostachyus (877/100 g of dry soil) trees than outside the canopy (547 and 588/100 g of dry soil, respectively). The level of root colonization of C. macrostachyus (45 %) was higher than A. gummifera (41 %). Root colonization of maize crops grown under the canopy of A. gummifera and C. macrostachyus trees was significantly higher than outside the canopy (P < 0.001). Maize seedlings grown on non-sterilized soils collected under and outside the canopy of A. gummifera and C. macrostachyus trees recorded higher root colonization, plant height, shoot and root dry weight than grown on sterilized soils (P < 0.001). The percentage of AM colonized roots of Zea mays seedlings was significantly positively correlated with the number of spore counts for field soils. The rhizospheres of indigenous agroforestry perennial species are important source of inoculum for annuals. The integration of perennials and annuals in an agroforestry system enhances the maintenance of soil quality in the tropics. 相似文献
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Emiru Birhane Nakiguli Fatumah Kidane Gidey Amanuel Zenebe Ssemwanga Mohammed 《林业研究》2018,29(3):675-686
Arbuscular mycorrhiza fungi(AMF) are vital in the regeneration of vegetation in disturbed ecosystems due to their numerous ecological advantages and therefore are good indicators of soil and ecosystem health at large. This study was aimed at determining how the seasonal, vegetation cover density, edaphic and anthropogenic factors affect AMF root colonization(RC) and spore density(SD)in Desa'a dry Afromontane forest. AMF RC and SD in the rhizosphere of five dominant woody species, Juniperus procera, Olea europaea, Maytenus arbutifolia, Carissa spinarum and Dodonaea angustifolia growing in Desa'a forest were studied during the rainy and the dry seasons in three permanent study vegetation cover density plots(dense, medium, and poor). Each plot(160 x40 m~2) has two management practices(fenced and unfenced plots) of area. A 100 g sample of rhizosphere soil from moisturefree composite soil was used to determine spore density.Spore density ranged from 50 to 4467 spores/100 g soil,and all species were colonized by AMF within a range of 4–95%. Glomus was the dominant genus in the rhizosphere of all species. Vegetation cover density strongly affected SD and RC. The SD was significantly higher(p 0.05) in the poor vegetation cover density than in the other two and lowest in the dense cover; root colonization showed the reverse trend. Management practices significantly(p 0.05) influenced AMF SD and RC, with the fenced plots being more favoured. Seasons significantly(p 0.05) affected RC and SD. More RC and SD were observed in the wet period than the dry period. Correlating AMF SD and RC with soil physical and chemical properties showed no significant difference(p 0.05) except for total nitrogen. Disturbance, vegetation cover density, season and total nitrogen are significant factors that control the dynamics and management interventions to maintain the forest health of dry Afromontane forests. 相似文献
3.
This study assessed the arbuscular mycorrhizal (AM) status of Boswellia papyrifera (frankincense-tree) dominated dry deciduous woodlands in relation to season, management and soil depth in Ethiopia. We studied 43 woody species in 52 plots in three areas. All woody species were colonized by AM fungi, with average root colonization being relatively low (16.6% – ranging from 0% to 95%). Mean spore abundance ranged from 8 to 69 spores 100 g−1 of dry soil. Glomus was the dominant genus in all study sites. Season had a strong effect on root colonization and spore abundance. While spore abundance was higher (P < 0.001) in the dry season in all three study sites, root colonization showed a more variable response. Root colonization was reduced in the dry season in the site that was least subject to stress, but increased in the dry season in the harshest sites. Management in the form of exclosures (that exclude grazing) had a positive effect on spore abundance in one of the two sites considered. Spore abundance did not significantly differ (P = 0.17) between the two soil depths. Our results show that in this arid region all trees are mycorrhizal. This has profound consequences for rehabilitation efforts of such dry deciduous woodlands: underground processes are vital for understanding species adaptation to pulsed resource availability and deserve increasing attention. 相似文献
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Emiru Birhane Mengsteab Hailemariam Girmay Gebresamuel Tesfay Araya Kiros Meles Hadgu Lindsey Norgrove 《林业研究》2020,31(1):313-323
Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on different land uses.We quantified the growth and nutrient uptake of F.albida seedlings inoculated with AM from different sources.These efforts were based on soil and fine root samples from the rhizosphere soils of F.albida trees.AM root colonization was determined using the gridline intersect method.Spores were extracted by the wet sieving and decanting method and identified to genus level.The seedling experiment had a completely randomized onefactorial design with four treatments and five replications.Faidherbida albida seedlings were grown in a greenhouse.All in situ F.albida trees were colonized by AM fungi.AM root colonization of F.albida trees was significantly higher(P<0.0086)in area exclosures than on lands used for grazing or cultivation.Spore abundance was significantly higher(P<0.0014)in area exclosures followed by cultivated land and grazing land.Glomus was the dominant genus in all land-uses.AM-inoculated F.albida seedlings grew better(P<0.05)than non-inoculated controls.Seedlings inoculated with AM from area exclosure had significantly(P<0.05)higher growth and nutrient uptake than those inoculated with AM from grazing and cultivated land.This emphasizes the importance of the native soil AM potential for better establishment of seedlings to achieve optimum plant growth improvement and assist in rehabilitation of degraded arid lands. 相似文献
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Kibru Tigist Husseini Rikiatu Birhane Emiru Haggar Jeremy Solomon Negasi 《Agroforestry Systems》2021,95(7):1327-1342
Agroforestry Systems - Farmer Managed Natural Regeneration (FMNR) is a rapid, low cost and easily replicated approach to restore and improve degraded agricultural, forest and pasture lands. The... 相似文献
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Gebremeskel Destaalem Birhane Emiru Rannestad Meley Mekonen Gebre Semae Tesfay Girmay 《Agroforestry Systems》2021,95(7):1275-1293
Agroforestry Systems - Agroforestry plays a significant role in climate change mitigation through improved sequestration and storage of carbon in farmlands. However, quantitative information on... 相似文献
8.
Florent Noulekoun Emiru Birhane Stella Chude Amanuel Zenebe 《Agroforestry Systems》2017,91(1):123-135
Concerns about sustainable management and conservation of multipurpose trees in their habitat have led to increased number of studies on the ecological characterization of their population. Such knowledge on Faidherbia albida, the most used tree in agroforestry parklands in Ethiopia, is limited. F. albida population was characterized in and compared between two agroforests having different conservation status in Northern Ethiopia. Population structural parameters along with environmental factors and human activities were assessed in 42 randomly installed plots using a transect method. Size class distribution was used to describe and analyze the species long-term population dynamics. Adult density was almost three times higher in Zongi agroforest (19.9 ± 2.9 trees ha?1) where the species has been conserved and managed for longer time compared to Abraha-atsbeha agroforest (7.9 ± 2.5 trees ha?1). The same trend was observed for tree morphological parameters which were significantly higher at Zongi than Abraha-atsbeha. However, size class distributions coefficient of skewness and the median diameter indicated a declining and vulnerable population at Zongi and an increasing population at Abraha-atsbeha. Species population characteristics were influenced by environmental factors such as altitude, stone cover, erosion severity, slope, and human-related disturbances including land use, fodder harvesting, distance away from the center of the village and proximity of household to the plots. The study confirms the impact of conservation, environmental factors and human disturbances on shaping F. albida population and recommends the consideration of the trade-offs between them to design effective conservation and management strategies to sustain F. albida agroforests. 相似文献
9.
Does communal forest intervention management enhance forest benefits of smallholder farmers? Evidence from Hugumbirda forest,Tigray, Ethiopia 总被引：1，自引：1，他引：0
Gidey Kidu Bereket Gebremedhin Emiru Birhane Habtemariam Kassa 《Journal of Sustainable Forestry》2017,36(3):264-276
Forest rehabilitation activities within centrally controlled state-owned forests in Ethiopia could not deliver communities with increased income. A study aiming to assess the benefits of forests for smallholder farmers whose land falls close to the state forest was conducted in Hugumbirda and Endedo kebele, two villages located adjacent to the Hugumbirda forest. Semi-structured questionnaires were used to collect data from 251 randomly selected households living near or adjacent to the state forest. A logit model was used to analyze factors affecting household’s willingness to scale up forests at the communal level. Most of the respondents living near or adjacent to the national forest were found to be dependent on the forest for fuelwood and therefore energy, timber products, and farming equipment. Furthermore, households were found to perceive that communal intervention management is a significant factor in attempts to further scale up forests. Scale-up of forests at the community was one option to enhance the vegetation cover and therefore increase primary production by promoting infiltration and decrease evaporation and runoff water. Finally farmers have suggested the state forest should be devolved to the community to improve the current level of forest contributions to the livelihood of smallholder farmers. 相似文献
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Stella Nwawulu Chiemela Florent Noulekoun Amanuel Zenebe Nigussie Abadi Emiru Birhane 《Agroforestry Systems》2018,92(5):1317-1328
The interaction of human land use, steep slopes and erosion has been a serious threat to Ethiopia’s ecosystems. Community’s initiated land rehabilitation programmes such as tree regeneration on farm lands, hill-side planting and exclosures have been established to rejuvenate debilitated lands. To characterize, map out and monitor such transformations, this study was carried out in Zongi, Tigray Region of northern Ethiopia. The study used an integration of remote sensing data, field observations and information from key informants and randomly selected respondents to analyse the land-use/land cover (LULC) changes from 1984 to 2013. Conventional method of supervised image classification was used for landsat image of 2013 while hybrid method of unsupervised and supervised classification was employed for landsat images of 1984 and 1999. The results revealed significant modifications and conversion of LULC types over the multi-dates. Analysis of the 29-year change matrix revealed that 78.5% of the land underwent significant changes in LULC. The major changes to agroforestry land use(LU)types between 1984 and 2013 were conversion of intensively cultivated land to moderately cultivated land (32.1%) and sparsely cultivated land (11.8%). The drivers of changes were linked to the introduction of land rehabilitation initiatives, government consensus (via agricultural extension) with the community, which were complemented by growing awareness of landowners. This study corroborates the necessity of community involvement and participation to improve their land use systems for environmental sustainability and sustainable livelihood. 相似文献