Balia Nala is the outlet of the Nainital lake, flowing towards southeast direction. Presence of Nainital habitation at its right bank has high socio-economic importance. This study presents the stability analysis of a...Balia Nala is the outlet of the Nainital lake, flowing towards southeast direction. Presence of Nainital habitation at its right bank has high socio-economic importance. This study presents the stability analysis of a ravine/valley along Balia Nala. Variegated slates(lower Krol and upper Blaini formations) are the main rock types, wherever the outcrop does exist and rest of the area is covered by slope wash and river borne materials. Three sets of joints are presented in the area, but 4 sets of joints also exist at some locations. Nainital lake fault intersected by Manora fault from southwest direction passes through eastern side of the study area, and some small faults, which are sub-branches of Nainital lake fault, are observed(with 10 m offset) and promote the landslide in the area. This study shows that different kinds of discontinuities(joints, faults and shear zones) and rapid down cutting by the stream due to neotectonic activity affect the stability of the slope. The fragile lithology and deep V-shaped valley further accelerate the mass movement in the study area. In addition, rock mass rating(RMR), factor of safety(FOS) and graphical analysis of the joints indicate the study area as landslide-prone zone. This study will be helpful in not only reducing the risk on life of people, but also in assisting the ongoing civil work in the study area.展开更多
Objective:To undertake a study on prevalence of Deg Nala disease in eastern states of India and to reproduce the disease in buffaloes by the Fusarium spp.,isolated from the affected region. Methods:During this investi...Objective:To undertake a study on prevalence of Deg Nala disease in eastern states of India and to reproduce the disease in buffaloes by the Fusarium spp.,isolated from the affected region. Methods:During this investigation,a survey was conducted covering four states of eastern region to identify the Deg Nala cases as well as to isolate and characterize the causative agent(s). An experimental study was carried out to reproduce the disease in healthy male buffaloes(2-3 years age) by randomly dividing them into five groups(four in each group).Each individual group was fed with rice straw artificially infested with either of the two representative isolates of Fusarium oxysporum(F.oxysporum)(F01,F02) or representative reference strains of Fusarium equiseti(F.equiseti)(ITCCF-2470) and Fusarium moniliforme(F.moniliforme)(ITCCF-4821) for 30 days,whereas the control group was fed with normal rice straw only.Results:A total of 658 Deg Nala cases were recorded and 12 Fusarium isolates were identified from the mouldy rice straw collected from these affected areas.The characterization of the isolates revealed three species viz.,F.oxysporum,F.equiseti and F.moniliforme,among which F.oxysporum was predominant.The disease was artificially reproduced in three buffaloes in F01 group and one in F02 group within 20-23 days by feeding F.oxysporum infested rice straw which resembled the clinical symptoms and gross lesions of natural Deg Nala cases.Conclusions:The field investigation and laboratory studies,including experimental production of Deg Nala disease suggest the possible involvement of mycotoxins.However,further investigations needs to be done to understand nature of the toxic factors involved in production of the Deg Nala disease.展开更多
文摘Balia Nala is the outlet of the Nainital lake, flowing towards southeast direction. Presence of Nainital habitation at its right bank has high socio-economic importance. This study presents the stability analysis of a ravine/valley along Balia Nala. Variegated slates(lower Krol and upper Blaini formations) are the main rock types, wherever the outcrop does exist and rest of the area is covered by slope wash and river borne materials. Three sets of joints are presented in the area, but 4 sets of joints also exist at some locations. Nainital lake fault intersected by Manora fault from southwest direction passes through eastern side of the study area, and some small faults, which are sub-branches of Nainital lake fault, are observed(with 10 m offset) and promote the landslide in the area. This study shows that different kinds of discontinuities(joints, faults and shear zones) and rapid down cutting by the stream due to neotectonic activity affect the stability of the slope. The fragile lithology and deep V-shaped valley further accelerate the mass movement in the study area. In addition, rock mass rating(RMR), factor of safety(FOS) and graphical analysis of the joints indicate the study area as landslide-prone zone. This study will be helpful in not only reducing the risk on life of people, but also in assisting the ongoing civil work in the study area.
文摘Objective:To undertake a study on prevalence of Deg Nala disease in eastern states of India and to reproduce the disease in buffaloes by the Fusarium spp.,isolated from the affected region. Methods:During this investigation,a survey was conducted covering four states of eastern region to identify the Deg Nala cases as well as to isolate and characterize the causative agent(s). An experimental study was carried out to reproduce the disease in healthy male buffaloes(2-3 years age) by randomly dividing them into five groups(four in each group).Each individual group was fed with rice straw artificially infested with either of the two representative isolates of Fusarium oxysporum(F.oxysporum)(F01,F02) or representative reference strains of Fusarium equiseti(F.equiseti)(ITCCF-2470) and Fusarium moniliforme(F.moniliforme)(ITCCF-4821) for 30 days,whereas the control group was fed with normal rice straw only.Results:A total of 658 Deg Nala cases were recorded and 12 Fusarium isolates were identified from the mouldy rice straw collected from these affected areas.The characterization of the isolates revealed three species viz.,F.oxysporum,F.equiseti and F.moniliforme,among which F.oxysporum was predominant.The disease was artificially reproduced in three buffaloes in F01 group and one in F02 group within 20-23 days by feeding F.oxysporum infested rice straw which resembled the clinical symptoms and gross lesions of natural Deg Nala cases.Conclusions:The field investigation and laboratory studies,including experimental production of Deg Nala disease suggest the possible involvement of mycotoxins.However,further investigations needs to be done to understand nature of the toxic factors involved in production of the Deg Nala disease.
