DEPLETION OF STRATOSPHERIC OZONE

DEPLETION OF STRATOSPHERIC OZONE

ABSTRACT

Depletion of stratospheric ozone emerged as a political concern in the early 1970s in the United States in the debate over the devel­opment of a commercial fleet of supersonic transports. In the mid- 1970s it became a major political issue with regard to the use of CFCs in aerosol spray cans, and in 1978 the United States banned the nonessential use of CFCs as aerosol propellants. Efforts at ne­gotiating an international agreement controlling CFC use began in the 1980s and culminated in the 1987 Montreal Protocol. This paper traces the evolution of policy responses to stratospheric ozone de­pletion. The evolution of stratospheric ozone depletion policy can best be understood as a two-stage process. The first stage involves the emergence of stratospheric ozone depletion as a domestic issue in the United States and several other countries in the 1970s, while the second stage focuses on its transformation to an international issue in the 1980s. In addition to the emergence of stratospheric ozone depletion as an international political issue, three other factors are important in understanding the sources of the Montreal Protocol: (/) the evolving scientific understanding of the problem, (2) increas­ing public concern over the problem based on the threat of skin cancer and the discovery of the Antarctic ozone hole, and (3) the availability of acceptable substitutes for CFCs.

CHAPTER ONE/INTRODUCTION

Representatives from 24 nations, meeting in Montreal in September 1987, signed the “Montreal Protocol on Substances that Deplete the Ozone Layer,”1 an international agreement designed to reduce the world­wide production and use of chlorofluorocarbons (CFCs). This protocol is the result of years of negotiation fostered by the United Nations En­vironment Programme (UNEP) among the major CFC producing coun­tries. Its formulation was a response to a growing international consensus on the need to protect stratospheric ozone from depletion by CFCs. The Montreal Protocol is a landmark agreement in that it is the first inter­national treaty for mitigating a global atmospheric problem before serious environmental impacts have been conclusively detected. As such, the Montreal Protocol has stirred much interest, and both scientists and pol­icymakers have suggested that it can be used as a model for international agreements on other global environmentalproblems, especially the prob­lem of CO2 and trace-gas induced global warming.

Before such a comparison to other environmental problems can be made, however, it is useful to understand the Montreal Protocol in its historical and political context. Depletion of stratospheric ozone is an example of both the complicated and the global nature of contemporary environmental problems, and the Montreal Protocol shows that innovative approaches to such global environmental problems are possible. During the past two decades concern over stratospheric ozone has evolved from a fringe environmental issue to a major policy issue of national and international importance. An analysis of this evolution is important for understanding both the value of the Montreal Protocol and its implications for other global atmospheric problems.

The evolution of stratospheric ozone policy can be understood as a two-stage process: (1) the development of domestic regulations controlling CFC use in aerosol spray cans in the United States and several other countries in the mid- and late-1970s, and (II) the development of an international policy response to the problem of global stratospheric ozone depletion in the 1980s. These are not separate issues. The development of an international response clearly followed from the concern raised in the United States, Canada, Sweden, and other countries which had taken unilateral action to control CFCs in the 1970s. However, many important differences between stage 1 and II make this distinction a useful tool for analysis. I argue that four key factors are important in understanding the evolution of stratospheric ozone policy: (1) the recognition that ozone depletion is a global problem requiring an international response; (2) the evolving scientific understanding of stratospheric ozone depletion and its influence on policymakers; (3) increasing public concern based on the threat of skin cancer and the perception of the potential for global catas­trophe associated with the discovery of the Antarctic ozone hole; and (4) the availability of acceptable substitutes for CFCs.

This paper analyzes the evolution of stratospheric ozone policy. The first section reviews the science behind the problem of CFC-induced stratospheric ozone depletion. The next two sections discuss the emerg­ence of stratospheric ozone depletion as a national political issue in the United States during stage I, and its evolution to an international political issue during stage II. This is followed by a discussion of how the evolving scientific understanding of the problem, the catastrophic nature of the risks, and the availability of alternatives to CFCs influenced the final negotiations on an international agreement. The last section examines the Montreal Protocol and discusses its prospects for success.

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THE COMPARATIVE EFFECT OF MYRISTICA FRAGANS

THE COMPARATIVE EFFECT OF MYRISTICA FRAGANS (NUTMEG) AND AFRAMOMUM MELEGUETA (ALLIGATOR PEPPER) ON DEMESTES MACULATUS DEGEER.

CHAPTER ONE

1.0  INTRODUCTION

Fish protein is known to be the best and cheapest source of animal protein (Olayide 1973). The loss of protein in dried fish due to the fish pest, D. Macuatus has been variously studied. Fish is a perishable commodity especially in the tropics where high temperature and humidity accelerate spoilage and Biodeterioration of fish immediately after catch. As a result of this, efforts are primarily directed towards the preservation of fish for human food. However, poor handling, inadequate processing facilities, lack of ice or storage facilities, remoteness of the fishing villages to urban market centers and poor distribution channels have drastically reduced fish utilization in the tropics (Ames,1992). Efforts at the use of synthetic insecticides and other methods to control D. Maculatus have not presented pleasant results. This has led to a search for alternative source of user friendly methods especially the use of botanicals to control D. Maculatus (Okorie et al 1991).

The use of chemical pesticides has helped to increase the yields obtained but one of the major problems with the constant use of chemicals is that resistance can be induced in target organisms. Biological method of control has been preferred in some cases because it is selective with no side effect and cheap. Resistance to biological control is rare and biological control agents are self propagating and self perpetuating (Okigbo and Ikediugwu 2000; Okigbo, 2003—-2005).

Plant extracts have been used successfully to control insect pests in the tropics. (Amadioha and Obi, 1999; Onitade 2000. Emoghene, 2004). The practice of applying synthetic insecticides has been found to be potentially dangerous when such fish is consumed. In some villages in Ghana where fish have been treated in this manner, people who consumed them, suffered blurred vision, dizziness and vomiting (Bull 1982).

Losses due to this pest of products of animal origin have been properly documented for a very long time (Aret, 1964, Willams 1956, Proctor, 1970, Kimura and Takakura).

Dry fish is however susceptible to pest infestation. Osuji (1973) noted that D. Maculatus is the major pest of dry fish with occasional presence of others like Necrobia rufipes, Tribolium, Castenum and Trogoderma, granamium. The two are pests of other products. The importance of D. Maculatus in Nigeria has been highlighted (Hayward 1961). Researches have extended to the use of extracts of water and alcohol extracts of such botanicals as P. guineese, Xylopia aethiopica, Myristica fragrans etc.

All these have proved effective but methods of extraction have proved to be very expensive and not even within the reach of the common market woman hawking her dry fish in the market. The crude powder, though effective in most cases are cumbersome in application and may even negate the rates of application and affect the appearance of dried fish.

This study is seeking the best and most effective way of applying these botanicals to the fish so that it will appear like ordinary dry fish edible and resistant to infestation of D. maculates and possibly other pest.

Water and alcohol are edible solvents that could be used to infuse the active ingredients in plant  extracts for the control of insect pests of smoke-dried fish.

The simple methods engaged could be steaming, boiling and soaking fish in such media in which different doses of the botanicals are tested. The botanicals to be used are alligator pepper; (A. Melegueta) and nutmeg M. fragans.

Our target is to find out the following;

  • To investigate Whether the active ingredients of M. fragrans and A. Melegueta can be infused into the fish through water and absolute alcohol extracts and used to control insect pest (Dermestes maculatus) of smoke-drised fish.
  • To compare the result obtained (mortality rate) with documented result of crude powder treatment which were found to be effective in controlling the insect pest.
  • To find out if fish treated with solutions of these botanicals at different concentration will still be palatable and aesthetically attractive
  • To compare the effective needs of the botanicals used.

To profer recommendations based on my findings

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EFFECTS OF FERTILIZER LEVELS AND HARVEST TIME ON YIELD OF Panicum maximum cv. Mombasa AND ITS NUTRIENT DIGESTIBILITY BY RED SOKOTO BUCKS

ABSTRACT

The first study was carried out to determine the effects of application of varied levels of fertilizer (NPK 15-15-15) and harvest time on yield and chemical composition of Panicum maximum cv. Mombasa in Shika, Northern Guinea Savannah of Nigeria.The experiment was laid out in 4×3 factorial arrangements in Randomised Complete Block Design (RCBD) with 3 replicates (Blocks). The 2 factors were fertilizer levels (0, 200, 300 and 400 Kg/ha NPK 15-15-15) and harvest time (8, 10, and 12 weeks after planting, WAP). The fresh and dry matter yields of Panicum maximum cv. Mombasa were influenced positively with increasing levels of fertilizer and harvest time. Total dry matter increased significantly (P<0.05) from 2.30 tonnes/ha in the control to 4.20 tonnes/ha in 400kg fertilizer applied treatment and total fresh weight also increased significantly (P<0.05) with age, from 8.6 tonnes/ha at 8th week to 21.00 tonnes/ha at week 12 after planting. 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It can be concluded that the application of NPK (15-15-15) at the rate of 400kg/ha improved the nutritive value and yield of Panicum maximum cv. Mombasa. Panicum maximum cv. Mombasa was at its best nutritive value at 8th week after planting but yielded more dry matter at 12th week after planting. Thus, farmers are encouraged to apply NPK (15-15-15) at 400kg/ha and harvest Panicum maximum cv. Mombasa at 10th week for better forage in terms of nutritive value and yield. The second experiment was conducted to investigate the effects of Concentrate inclusion levels on nutrients digestibility and Nitrogen balance in Red Sokoto bucks fed Panicum maximum cv. Mombasa based diets. The Concentrate inclusion levels were 15, 30, 45 and 60 % (Treatments 1, 2, 3 and 4, respectively). Twelve (12) Red Sokoto bucks were randomly assigned to the four treatments in a Completely Randomised Design (CRD).Dry matter digestibility was significantly (P<0.05) higher in bucks fed diet containing 60% Concentrate (75.21%) compared to the other three Treatments. Bucks fed diet containing 60% Concentrate had the highest (P<0.05) Organic matter digestibility (75.32%) compared to the other Treatments. Nitrogen free extract and Neutral detergent fibre digestibility followed a similar pattern of change as in Organic matter. Bucks fed Treatments with 45 and 60% Concentrate inclusion showed significantly (P<0.05) higher ether extract digestibility compared to those fed 15 and 30 %. Crude fibre digestibility was significantly (P<0.05) higher in bucks fed diet containing 30% Concentrate (84.59). Treatments 3 and 4 were similar, whereas Treatment 1 recorded the lowest (68.74%) crude fibre digestibility. Crude protein digestibility increased with increasing Concentrate levels. Highest (P<0.05)CP digestibility values were observed in bucks fed diet containing 60% Concentrate (81.77%) while bucks fed diet containing 15% Concentrate recorded the least values. Acid detergent fibre digestibility followed a trend similar to that of crude protein. Nitrogen intake increased significantly (P<0.05) with an increase in Concentrate levels. Bucks fed diet containing 60% Concentrate (8.36g/day) were significantly higher (P<0.05) in Nitrogen intake. Faecal nitrogen loss decreased significantly (P<0.05) as Concentrate inclusion levels increased (from 1.52 g/day in treatment with 60% Concentrate to 2.32 g/dayin treatment with 150%), while Urine nitrogen loss followed a trend opposite to that of faecal nitrogen loss. The highest (P<0.05) Total Nitrogen excreted was observed in treatment 3 (3.00g/day). Nitrogen retained was similar in bucks fed diet containing 30 and 60% Concentrate but was significantly higher (P<0.05) in bucks fed diet containing 15 and 45% Concentrate. Nitrogen absorbed as a percentage of intake and Nitrogen retained as a percentage of intake followed the same pattern. Bucks fed diet with 60% Concentrate inclusion were significantly higher (P<0.05) while bucks fed diet containing 15 and 45% Concentrate were lower in these parameters. In conclusion, the inclusion of Concentrate in Panicummaximum cv. Mombasa based diet increased the diet’s intake, digestibility and Nitrogen retention in Red Sokoto bucks. It is therefore recommended that farmers could incorporate 60% Concentrate in a Panicummaximum cv. Mombasa based diet for improved digestibility and nitrogen retention in Red Sokoto bucks.

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Problem of Fish farming teaching in secondary School in Obi and Oju of Benue State

INTRODUCTION

According to Education for All (EFA) Global Monitoring Report (2015) analysis of survey data showed that many countries exhibited persisting rates of part time work by students. This is despite the increased school coverage seen in many countries. The report pointed out that substantial proportion of adolescents continued working alongside their normal schooling activities. For example, in Cameroon, about 70 per cent of students aged 12 to 14 worked in 2001 with little change observed by 2011.

In a study carried out in Thailand by the International Labour Organization (ILO) in 2013, half of those engaged in fishing ranged between the age of 18-28 years old and of a particular note of the sample population was the presence of seven fishers that were below age of 15 and 26 fishers that were between 15 to 17 years of age. The report established that majority of the fishers studied, had little in the way of education with 58 percent interviewed having utmost five years of formal schooling, and only a small proportion had completed secondary school education.

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