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Sustainable management of communal grazing lands in Ethiopia is crucial to sustain livestock productivity and reduce land degradation. This study was conducted in Dera district, Ethiopia, to assess local communities’ perceptions of the degradation and their attitudes on the management of communal grazing lands. Household surveys, group discussions, and the contingent valuation method were used to gather data. Results indicated that local communities are aware of the degradation and are willing to participate in the management of communal grazing lands by contributing labor and cash. Labor contribution is positively and significantly correlated to total livestock units (TLU) and credit, and negatively correlated with household size and extension service. Significant correlation between the willingness to contribute cash and TLU was also detected. Community participation and discussions, demarcation of boundaries, equity in benefit sharing, and engaging both formal and informal institutions are crucial to sustain and enhance the effectiveness of grazing land management. 相似文献
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Gebreyohannes Tesfamichael De Smedt Florimond Walraevens Kristine Gebresilassie Solomon Hussien Abdelwassie Hagos Miruts Amare Kassa Deckers Jozef Gebrehiwot Kindeya 《Hydrogeology Journal》2017,25(3):639-655
Hydrogeology Journal - The Geba basin is one of the most food-insecure areas of the Tigray regional state in northern Ethiopia due to recurrent drought resulting from erratic distribution of... 相似文献
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E. Amare F. Kebede W. Mulat 《International Journal of Environmental Science and Technology》2017,14(8):1679-1688
The present study monitored textile factory, distillery, and domestic wastewaters and investigated the effects of blending on the physicochemical properties of these wastes. Findings revealed that distillery wastewaters had the highest values of all tested parameters, including heavy metals, biodegradable organics, and nutrients. Biological and chemical oxygen demands in the textile wastewater were higher than domestic wastewater, while total phosphorus, total nitrogen, and sulfate were higher in the domestic wastewater. Likewise, while higher mean concentrations of zinc, copper, iron, and manganese were found in the domestic wastewater, the rest studied heavy metals did not show statistical differences (p < 0.05). This study concluded that blending improves biological treatability and effectively neutralizes the alkaline textile, acidic distillery, and domestic wastewaters at volumetric ratios of 3:1:18, respectively. This methodology will help to avoid the use of chemicals for neutralization and can be a useful entry point to establish sustainable wastewater management strategy in the developing countries. The results suggest the need for inclusion of the tested nine heavy metals in the Ethiopian standards for discharge from the distillery and domestic effluents. 相似文献
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Abstract— One hundred and thirteen Australasian tektites from Vietnam (Hanoi, Vinh, Dalat, and Saigon areas) were analyzed for their major and trace element contents. The tektites are either of splash form or Muong Nong‐type. The splash‐form tektites have SiO2 contents ranging from 69.7 to 76.8 wt%, whereas Muong Nong‐type tektites, which are considerably larger than splash‐form tektites and have a blocky and chunky appearance, have slightly higher silica contents in the range of 74–81 wt%. Major‐element relationships, such as FeO versus major oxides, Na2O versus K2O, and oxide ratio plots, were used to distinguish the different groups of the tektites. In addition, correlation coefficients have been calculated for each tektite group of this study. Many chemical similarities are noted between Hanoi and Vinh tektites from the north of Vietnam, except that the Hanoi tektites contain higher contents of CaO than Vinh; the higher content of CaO might be due to some carbonate parent material. Both Dalat and Saigon tektites have nearly similar composition, whereas the bulk chemistries of the tektites from Hanoi and Vinh appear different from those of Saigon and Dalat. There are differences, especially in the lower CaO and Na2O and higher MgO, FeO, for the tektites of Dalat and Saigon in comparison to that of Hanoi tektites. Furthermore, the Dalat and Saigon tektites show enrichments by factors of 3 and 2 for the Ni and Cr contents, respectively, compared to those of Hanoi and Vinh. The difference in chemistry between the North Vietnam tektites (Hanoi, Vinh) to that of South Vietnam tektites (Saigon, Dalat) of this study indicate that the parent material was heterogeneous and possibly mixing between different source rocks took place. Muong Nong‐type tektites are enriched in the volatile elements such as Br, Zn, As, and Sb compared to the average splash‐form tektites of this study. The chemical compositions of the average splash‐form and Muong Nong‐type tektites of this study closely resemble published data for average splash‐form and Muong Nong‐type indochinites, indicating that they have the same source. The trace element ratios Ba/Rb (2.7), Th/U (5.2), Th/Sc (1.3), Th/Sm (2.2), and the rare earth element (REE) abundances of this study show close similarities to those of average upper continental crust. 相似文献
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The paper demonstrates two issues; (i) how a ‘moving window approach’, that translates pixel level detected changes to landscape level, can be implemented; (ii) how the approach can overcome the limitations of pixel level change information to characterize change over large areas. First we detected changes from two periods (1986 and 2010) of LULC maps. On the pixel-based changes, we ran focal statistics summation operator separately for selected window sizes (1–10 km). Further, we assessed effect of scale in depicting the pattern and amount of change. The approach is found useful to overcome major shortfalls of pixel-based change characterization. However, varying scale of analysis provide varying amount of change and differently represent change patterns. Thus, implementing the approach over complex and large areas requires multi-scale approach. Subdividing complex and large areas into homogeneous zones can help to implement the multi-scale approach and facilitate the selection of appropriate scale of analysis. 相似文献
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Information on use/land cover change is important for planners and decision makers to implement sustainable use and management of resources. This study was intended to assess the land use land cover (LULC) change in the Koga watershed. The MSS of 1973, TM images of 1986, 1995 and 2011 were used together with survey and demographic data to detect the drivers of land cover changes. The result revealed that a remarkable LULC change occurred in the study area for the past thirty eight years. The area of cultivated and settlement has increased by 7054.6 ha, while, grass and bush lands decreased by 4846.5 and 3376 ha respectively. Wetland also declined from 580.2 ha to 68.3 ha. The growing demand for cultivable land and fuel wood were the major causes to the deterioration of grass and bush lands. Hence, the appropriate land use policy should be employed to sustain available resource in the watershed. 相似文献
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