The results of analysis in (Tables I and II) charcoal and firewood are the major source of cooking energy in urban Zanzibar, this tally with findings by Masoud (1993). Conventional fuel such as kerosene, electricity and may be gas is common. The findings also indicate that both households and institutional sectors use fuel combination strategy to avoid inconvenience caused by the availability and accessibility of both traditional and conventional sources of energy. In most cases wood is used together with charcoal and kerosene, whereas electricity is often replaced by, or complemented with charcoal.

Firewood per se is no longer being common source of energy. It appears that urban dwellers have switched to charcoal, which is cleaner for urban environment compared with charcoal. However, the choice between firewood and charcoal among urban families is not obvious. It seems to be dictated to a large extent by poverty, fuel wood cited to be cheaper compared to other sources of energy. Kerosene is an imported product and its price keeps rising all the time as a result of the continuous devaluation of Tanzania shillings. Currently, I litre of kerosene costs Tshs 980 (US$0.9) where an average a household with 5 to 6 member would need at least three liters per-day. Electricity is normally used as secondary energy source for lighting and operating home accessories (refrigerator, TV, radio, etc.). Its availability and cost discourage urban residents from using it for cooking purpose.

It has been observed that the concentrated demand of wood fuel in urban centers, and the incentives to cut trees created by a cash market, can dramatically increase the rate at which deforestation takes place and the loss of biodiversity. The study proves that potential energy source for cooking in urban Zanzibar is fuel wood. It is expected to remain so for several decades just because the shift towards conventional fuels seems to be very slow. Poverty and poor management planning in energy issues are the major reasons for such slow transformation. The study, however, found that (See Figure 1) society had shifted from firewood-based consumption to increased use of charcoal. This transformation does nothing in terms of reducing the amount of tree to be chopped down. This is mainly because the majority of urban dwellers burn charcoal inefficiently over traditional charcoal stove.

The linkages between urban fuel demand and rural deforestation have been established in many studies (Mashala, 1979; UNEP, 1980; Bhagavan, 1985; World Bank, 1994; World Resource Institute, 1994; Masoud, 1993). According to Persson (1994), cited in DCCFF (2002) Zanzibar, like any other African Island States, experienced 400,000 hectares loss per annum. In the study area fuel wood consumption per annum is estimated to be 463.92m³, taking a conversion factor of 0.023m³ and a mean of 36.5m³/ha; for Unguja Main Island this is almost 13 hectares loss of forest per annum. The Zanzibar fuel wood consumption per annum is estimated to be 301,238m³ taking a mean of 38.7m³/ha (for Zanzibar). This is almost 7783 hectares (DCCFF, 2002). Considering the slow rate of switching to conventional fuels due to poverty and poor energy plans, the low magnitude of tree planting efforts and recent tight measures to ban wood fuel importation from coastal mainland, the forests land of Zanzibar which is 264,300 hectares will be completely deforested up to the year 2040.

However, urban residents show preference in the certain wood species for fuel wood. Flamability, high calorific value, availability and culture have been found to be the main factors for the species preference. Species such as Areca catechu (mpopoo), Maytenus mossambiansis (mnusi), Rhus longipes (Mchegele), from coral rag forests, and Rhizophora mucronata (Mboko), Brugueira (msinzi) and Ceriops candoleana (mkandaa) from mangrove which are highly demanded according to Owen (1993) might be in danger. Thus, forests inventory in both coral rag and mangrove ecosystems is needed to check the status of plant species (Table III).

Three stone stoves (fire enclosed between three stones, bricks, mounds of mud or lumps of incompatible materials) are no longer famous in urban Zanzibar because the society is in a transition towards predominant charcoal. The use of this stove is not always influenced by poverty but rather its flexibility. People may use fire wood stoves in addition or as an alternative. Thus, some respondents use both three stone and charcoal stoves.

The traditional charcoal stove (seredani) in most cases is made from scrap metal cut from old car bodies, old oil drums or old iron roof, is produced by local artisans spread in many parts of urban Zanzibar. Seredani vary in durability and size, the durability depend on the frequency of usage and on the quality/thickness of scrap metal. The seredani is made in the form of a cylinder, with a perforated metal grate about half way up the inside. Pots supports are fixed to the top edge and project inward a few centimeters (Plate 1).

Both three stones and seredani are accused of being wasteful in energy. In addition three stones are highly associated with dirt, danger, and are inconvenient to use. Improved charcoal stoves look like seredani but have in addition, ceramic (soil) on its inner wall to save energy. It is believed that improved charcoal stoves use less amount of charcoal when compared with the traditional stoves. Improved charcoal stoves in many developing countries are seen as a tool for both poverty reduction and arresting rural deforestation.

Many diffusion researches in the past have pointed out the fact that when the number of users of a new product or invention is plotted against time, the resulting curve is typically an S-shaped or ogive distribution. This means adoption of new innovation (improved stoves) proceeds slowly at first, accelerates as it spreads throughout the adopters, and then slows down as the relevant population becomes saturated. It has been argued by Rosenberg (1976) that the S-shape is a result of heterogeneity among the individuals within social systems. Heterogeneity is normally influenced by variations among household in their educational levels, income, source of information and cultural attitudes.

The research findings show that only 25 percent of the households use improved charcoal stoves. None however, is use improved charcoal stoves among street side restaurants. The reason for the restaurants not to adopt the stoves is the fact that the size of the stoves is big enough to accommodate big cooking pots. On the other hand, traditional charcoal stoves made locally are available in all sizes even bigger sizes to accommodate the institutions cooking needs.

The interest for the production and dissemination of the improved charcoal stoves in Zanzibar started roughly in 1988. However, the whole issue of production and dissemination of these stoves is not convincing. Although the history of innovation tells us that the diffusion process of an innovation is characterized by overall slowness on one hand and the wide variations in the rate of acceptance of different invention on the other, one would wish to argue that there is slow rate of taking up of improved stoves in urban Zanzibar. This is mainly because after 17 years of stoves inventions in both Tanzania mainland and Zanzibar only 25 percent of the households had adopted the stoves. This argument in turn justifies the fact that diffusion of stoves in Zanzibar reaches the level of saturation before mass acceptance (Table IV).

On the other hand, it has been noted that some of the respondents had abandoned (discontinuance) the use of improved charcoal stoves. Discontinuance as defined by Rogers (1995) is a decision to reject an innovation after it had previously been adopted. It normally occurs when the individual becomes dissatisfied with an innovation. It has been found that most of the traditional stoves users had previously used improved charcoal stoves. The deficiency of improved charcoal stoves made them to abandon the use of those stoves. Most of the stoves do not last long. Commenting on the matter, Lombard (1995) argues that many stoves did not meet local needs and did not hold up to the rigors of daily use and within months, dissatisfied households abandoned their improved stoves.

In that case, the contribution of improved charcoal stoves in reducing fuel wood consumptions and thus check deforestation may not be easily appreciated. Since the findings of this study prove that the urban demand for fuel wood is the primary cause of rural deforestation, the impact of improved charcoal stoves in arresting depletion of fuel wood resources can only be realized when and if the improved charcoal stoves are widely diffused and used in urban Zanzibar.

In fact, the diffusion of improved charcoal stoves in all developing countries failed to achieve high rate of acceptance. This is because the stoves do not match with multiple local cooking needs. At this point the question that concerns both academicians and those interested in encouraging the spread of improved stoves in urban areas, is what factors affect the rate at which adoption occurs. The following sections analyze and discuss the factors affecting adoption of improved charcoal stoves in urban Zanzibar.

Costs of adopting the new technology remain a very important factor influencing the decision to adopt the new technology. In the case of improved charcoal stove, this includes the purchase price. It has been found that they are expensive; if one considers the durability of this stove the price of the stove acts as a disincentive for adoption. In most cases, urban residents opt to buy traditional charcoal stoves than improved ones since they have more advantages than improved stoves. The price of traditional charcoal stoves ranges from US$1.5 to US$3 depending on size and durability, while the improved stoves range from US$2.5 to US$5.

Level of schooling may influence the adoption of innovation in the social systems. Years spent in formal education may affect possibility of adopting an innovation and a likely source of inspiration for innovation. Cotlear (1990) argues that formal, non-formal and informal education may provide specific or general knowledge, which provides the benefit and uses of new technology. The result of the study shows that majority of the potential adopters (30.8 percent) have been in secondary schools. However, the majority of respondents who completed university and college education still cook over traditional stoves (three stones and traditional charcoal stoves). This finding does not tally with that Sharada and Knight (2000) in their study of adoption and diffusion of agricultural innovation in Ethiopia. They found that most of the potential adopters have been to school.

Traditionally, educated people were expected to understand the benefit of the innovation in question at a faster speed than the uneducated. But in most cases their decision might be affected by other factors such as economic condition and cultural attitudes. Importantly, their level of understanding should be enhanced by the information explaining the importance of the stoves to their social welfare and conservation of forests for their future generation. Unfortunately, such extension information cannot be found any where in the Zanzibar.

The choice to adopt improved charcoal stoves requires some information about its suitability, in order to reduce the level of uncertainty. According to Rogers (1995), there is a general implication that an innovation (for the case of this study improved charcoal stoves) has at least some degree of benefit or advantage for its potential adopters. But this advantage is not always clear or spectacular, at least not in the eyes of the intended adopters. Potential adopters can seldom be certain that an improved charcoal stove represents a superior alternative to the traditional one. The implication is that the improved charcoal stoves creates one kind of uncertainty in the mind of potential adopters about its possible consequences, as well as presenting opportunity to reduce uncertainty in another sense (that of the information base of improved charcoal stoves).

In reality, an individual normally wants to know the evaluation information about the stoves, what the consequences are, and what are the advantages and disadvantages. This gap of information in the mind of individuals needs to be filled in order to reach decisions as to whether to adopt or to reject it. Extension services of improved charcoal stoves through mass media (radio, TV, news paper, magazine, etc.) are often the most rapid and efficient means to inform the mass about the existence and suitability of the stoves.

One would wish to argue as to why then is the adoption of the improved stoves is marginal in urban Zanzibar. Probably, the prevailing information is incomplete for it to stimulate adoption, or the nature of the mass media is a one-way communication, which does not allow the exchange of ideas. It has been found out that for the case of Zanzibar, information about the stoves is influenced by the actions of the stakeholders (suppliers, departments concerned). In the case of the supplier, information in the form of advertisement can raise the cost of stove directly, and that will be another disincentive over the adoption of the stoves.

Apart from the mass media, the choice to adopt new innovations may also depend on the information available about the experience with the stoves in the decision makers' immediate environment, either from that in geographical proximity or from those with whom he or she interacts. The findings imply that social network and the neighbourhood effect has a minor effect on the adoption of improved charcoal stoves compared with mass media. Probably, the stoves were perceived inferior over traditional ones by the majority of potential adopters. Thus, discouraging feed back from the potential adopters to the late adopters decelerated the diffusion of new stoves. For example, in Plate 2, improved stoves had broken just after one month. In that case one would wish to argue that many defects associated with the improved charcoal stoves contributed to this low rate of adoption in many urban areas in developing countries.

Logically the information about the capacity of stoves in forest conservation was expected to come from energy and forests stakeholders and not from stove traders. Households that adopted the new stoves were asked if they knew the importance of the stoves on the conservation of forest resources. The findings revealed that the majority knew nothing about the importance of improved charcoal stoves. Probably, they adopted the stoves for prestige or for other reasons. Empirical findings confirm that the role of information on what Rogers (1983) considered as trialability and observability characters of innovation are very crucial ingredients in the diffusion and adoption of innovation in the social systems. The findings of this study justify the fact that consumer innovation like stoves is relatively less observable, and thus diffuse at extremely slow rate unless it should be highly promoted.

Apart from the factors analyzed and discussed in previous sections, culture may also be an important determinant for the diffusion rate. Hall (2003) argues that many people have stress differences in cultural attitudes towards risk and simple “a new ness”. These characteristics vary within cultures as well as between them, leading to dispersion in adopters rates that are not accounted for by economic variables.

A household survey revealed that some of the respondents continue using traditional stoves because they cook delicious food while other said due to customs laws. Detailed interview of these households shows that traditional cooking methods especially over three stones stoves cook food with smoke test, which is more preferred by these households. Similarly, traditional stoves produce light, heat and smoke all of which may be considered useful to them. It has been noted that in some households heat from open fire can be used for drying especially cassava during the rainy season. Improved charcoal stoves conserve heat, thus, they cannot have such capacity to generate enough heat for drying. Therefore, the designer of improved charcoal stoves have to consider traditional cooking needs of the adopters.

Traditional fireplace may provide social focus as well as have symbolic value. In Ghana the three stones symbolizes a united family while in parts of Nepal, people believe a spirit dwells in their traditional hearth (Gill, 1985). This means, cooking efficiency of improved charcoal stoves has little value in meaning. Rogers (1995) cites a number of situations where compatibility with existing social norms has strongly influenced the adoption of new innovation. The adoption of boiling water technology in the village of Los Molinos in Peru and various contraceptive measures in developing countries is highly influenced by cultural attitudes of adopters.

Efforts to improve the efficiency of cooking stoves have been increasingly popular in the developing world. Improved charcoal stoves perceived as real option for decelerating wood fuel resources particularly in the situation of poverty. Many sources cite the fuel efficiency of traditional stoves as 5 to 10 percent. In that case, the stoves consume large amounts of fuel wood, thus they are said to accelerate deforestation.

For decades, the question on whether improved stoves save wood, remains the area of hot debate among both academicians and stoves enthusiasts. Previous studies (Foley and Moss, 1983; Barnes, 1994) however, give both success and failure stories about the capability for improved stoves to save wood. The study by Foley and Moss (1983) shows that a few follow up studies met the requirements of basic statistical analysis and revealed that some of the survey found energy saving of 20-30 percent compared to open fire. However, other studies showed little savings. These noted variation among the stoves probably caused by the variation in the quality of stoves as influenced by materials and skills of the designers. In that case, it is difficult to predict the impact of stoves on both poverty reduction and arresting rural deforestation.

Interestingly, based on the perception of the potential adopters, the study shows that 100 percent of the potential adopters believed that their improved charcoal stoves save wood. The amount of charcoal used is smaller compare with previous consumption where they used traditional charcoal stoves or three stone stoves. A detailed study which involves close experiments is needed to measure the capacity of improved charcoal stoves in saving wood, to see whether improved charcoal stoves is a real policy option for the country to opt for.

On the other hand, the claim on as to whether the improved charcoal stoves reduce the rate of deforestation also evolved around debates among stoves enthusiasts for the decades. Few studies called the assertions over the capacity of stoves as over-optimistic. For them fuel wood for domestic use is rarely a major cause of forests depletion. In most areas the pressure on forest resources comes primarily from the need to obtain land for agricultural production. Thus, stoves programmes will have an impact only if supplies of wood come from untouched forests and not from land that is being cleared for agriculture.

The study proves that there is positive relationship between the urban fuel wood demand and deforestation in Zanzibar. The studies by Masoud (1993) in one way or another justify the study findings. On the course of this study various factors have been analyzed and it has been found that fuel wood demand is the primary cause for deforestation in both coral rag and some mangrove ecosystems. Plate 3 shows a portion of mangrove forest, which completely degraded for charcoal making near Unguja Ukuu Village, North of urban Zanzibar.

The study also proved that, shifting cultivation per se is no longer an important factor for deforestation. This is mainly because shifting cultivators are highly influenced by the power of urban fuel wood market. Their main objective is to get wood for sale rather then crop production. Again, the findings show some degree of saving wood in the use of improved charcoal stoves to compare with traditional stoves. One would wish to argue that the use of improved charcoal stoves may reduce the consumption rates of fuel wood and thus arrest rural deforestation. However, this can only be realized if the improved charcoal stoves attain mass acceptance in urban Zanzibar.