Chapter 7 Consumption Rates and Patterns of Woodfuel in Urban Area of
7.4. Results
7.4.1. Household characteristics in urban area
The household size ranged from 1 to 11 members representing average household size of 4.6 (Table 7.1). In education background, 4.5 % of household heads are graduates, 30.3 % went high school and the rest just got low education. The annual household income ranged from 720 $ to 24,000 $ representing the average annual income by 4338 ± 460 $. The main livelihood activities were government work, agricultural work, self-employed, labour work, and others etc., representing 19.7%, 3.0 %, 56.1%, 16.7%, and 4.5 % respectively. Six percent of sample households possess agricultural land, and maximum land possession was approximately 4.1 ha. Ninety-seven percent of sample households installed the electricity but the rest have not done yet because of their economic condition.
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Table 7.1. Household characteristics in urban and rural areas of Yedashe Township. Data of the rural area were obtained from chapter 6 (Win et al., 2018c)
Urban Rural
Number of household 66 137
Family size (number of family members) (mean ± SE) 4.6 ± 0.2 4.9 ± 0.2
Annual income (US$) (mean ± SE) 4338 ± 460 1686 ± 101
Electricity installment Yes
No
64 2
0 137
7.4.2. Patterns of cooking energy use in the urban area
As for cooking energy, 39.4% used firewood, and 56.1% used charcoal respectively.
About seven percent of sample households reported the use of only non-wood energy such as electricity, gas etc. Majority of the households were multiple-fuel-users; and woodfuel and other energy types were used in combination (Table 7.2). No household used agricultural crop residues, but 1.5 % of household used sawn-dust from nearby sawmills as a substitute for firewood and charcoal.
More than eighty percent of respondents who installed the electricity used electricity for cooking. However, due to its unstable and frequently run out conditions, the respondents had to use other energies such as firewood and charcoal as well as gas. Among the woodfuel users, the average numbers of the days when firewood and charcoal were used for cooking were about 20 days per month for both. There is no report for self-collection of firewood from natural forest, and woodfuel market is very common in the area. For the firewood users, only 3.8% used fuel-efficient stove and the rest used a three-stone fireplace for cooking.
Majority of the sample households cooked meals one time per day accounting 57.6% of all, while the rest, 1.5% and 40.9% cooked three times and two times per day, respectively.
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Table 7.2. Types of cooking energy consumed in urban area of Yedashe Township.
Number of households
Fraction of sample household according to
the type of energy use
Per-capita consumption (weight)(kg yr-1)
Per-capita consumption
(volume)
(m3 yr-1) Types of energy
Only Firewood 6 9.1 % 362.3 ± 107.0 0.5 ± 0.2
Electricity and Firewood 17 25.8 % 189.0 ± 40.2 0.3 ± 0.1
Only Charcoal 7 10.6 % 109.8 ± 18.3 0.7 ± 0.1
Electricity & Charcoal 28 42.4 % 62.0 ± 13.7 0.4 ± 0.1
Gas, Firewood & Electricity 1 1.5 % 21.6 ± 0.0 0.30 ± 0.00
Charcoal, Firewood &
Electricity
2 3.0 % 122.2 ± 50.2
(firewood) 19.5 ± 1.5 (charcoal)
0.2 ± 0.1 (firewood) 0.1 ± 0.01 (charcoal)
Non-woodfuel only 5 7.57%
Total 66 100%
Stove types in firewood users Fuel-efficient stove Parallel-brick stove Three-stone-stove
1 1 24
3.8 % 3.8 % 92.4 % Frequency of cooking
Once Twice Thrice
38 27 1
57.6 % 40.9 % 1.5 %
7.4.3. Sources, types, sizes, and species of woodfuel in urban area
There is no report for self-collection of firewood from natural forests. As shown in Figure 7.2, 69.1 % of firewood consumed in urban obtained from buying while 29.0 % from home-garden and other 1.9 % from wood residues from housing and furniture work. Among the firewood obtained from buying, 88.6 % were natural-forest-originated green wood, which is equivalent to 61.2% (=69.1%×88.6%) of a total of firewood consumed. No exact responses for size and species of firewood consumed were available during the interview, and thus the results reported for rural area of Yedashe township in chapter 6 (Win et al., 2018c) were applied for evaluating firewood demand and supply relationships. For the charcoal, the sources, size, and species preferences were also assumed to be the same with
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the results reported for rural area in chapter 6 (Win et al., 2018c) since those are major sources of charcoal production.
Figure 7.2. The sources of firewood consumed in urban area of Yedashe Township.
7.4.4. Woodfuel consumption rates in the urban area
As a total of multiple-fuel-users and single-fuel-users, average (± standard error) annual per capita firewood and charcoal consumption for cooking were 217 ± 39 kg year-1 and 69 ± 11 kg year-1, respectively, which are equivalent to 0.3 ± 0.1 m³ year-1 and 0.4 ± 0.1 m³ year-1 of solid wood, respectively (Table 7.3). Only for single-fuel-users, the consumption rates increased about 1.7 and 1.6 times of the total averages respectively, resulting 362 ± 107 kg capita-1 year-1 for firewood and 110 ± 18 kg capita-1 year-1 for charcoal.
The consumption rates in the urban area were about one-third for firewood (217 vs 780 kg) and one-fourth for charcoal (69 vs 280 kg) of those in rural area (Table 7.3). Even if it was compared with firewood-only and charcoal-only users of urban area with those of rural area, the consumption rates in the urban area were still less than half in urban area (362 vs 780kg for firewood; 110 vs 280 kg for charcoal).
The GLM results (Table 7.4) indicate that single-fuel users consistently had significantly higher consumption rates than multiple-fuel users for both firewood and charcoal. All of the other three independent variables were significant (p < 0.05) for firewood, while they all were not significant (p > 0.05) for charcoal. The per capita firewood consumption rates were higher for the households with less family members, more income
69.1
29.0
1.9 0.0
10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0
Buying Home garden Wood residues
% of total firewood consumed
Sources of firewood
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and more cooking frequency. The Durbin-Watson (DW) test (Zeileis and Hothorn, 2002) showed that there was no autocorrelation in the residuals from the GLM for firewood (DW = 2.484, p = 0.867) and charcoal (DW = 1.493, p = 0.068).
7.4.5. Estimating woodfuel demand and forest area needed to meet the demand
Woodfuel demand and supply in the urban areas are shown in Table 7.3 together the results from the rural area indicated in chapter 6 (Win et al., 2018c). Per capita demand of forest-originated green wood > 10 cm dimeter in the urban area was 38 kg and 293 kg for firewood and charcoal, respectively. Among the forest biomass density for all the standing trees ≥10 cm (45 t ha-1), 10.2 t ha-1 and 14.6 t ha-1 can be used for firewood and charcoal, respectively, as estimated in chapter 6 (Win et al., 2018c). As a result, forest area needed to meet the per capita demand for firewood and charcoal was 37 m2 and 201 m2, respectively.
For the whole urban population, forest area needed to meet consumptions of firewood and charcoal were 34 and 274 ha respectively, which were largely smaller than those (530 ha and 2900 ha, respectively) needed for rural consumptions at the whole township.
The forest area needed to meet the total demand of firewood and charcoal at the whole township including both urban and rural areas was estimated to be 3738 ha (Table 7.3).
This value decreased down to 1592 ha when rural people change their woodfuel rates and patterns (single-woodfuel users) into those that urban people currently adopted (multiple-fuel-users) (Figure 7.3). This reduction of the total demand for forest is largely contributed by the decrease in single-charcoal-users rather than single-firewood-users, as shown in Figure 7.3.
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Table 7.3 Summary of woodfuel demand and supply in the urban and rural areas. The values in the rural area were from Win et al. (2018c).
Firewood Charcoal
Unit Urban Rural Urban Rural Demand
Annual per capita consumption;
weight of the product Ccp 217 780 69 280 kg
weight for solid-wood equivalent Ccw 217 780 293 1,190 kg
volume for solid-wood equivalent Ccv 0.3 1.1 0.4 1.7 m3
Percentage of forest-originated green
wood Pg 61 16 100 100 %
Percentage of size ≥ 10 cm diamter P10 28 28 100 100 %
Per capita demand for forest-originated
green wood ≥ 10 cm diamter Dc= Ccw×Pg×P10 38 36 293 1,190 kg Number of woodfuel users in the
township Nr 9,159 153,666 13,651 35,578 persons
Total demand for the whole township Dt= Dc×Nr 344 5,460 3,993 42,340 t
Supply
Forest biomass density for all trees ≥
10 cm diamter Bt 45 45 45 45 t ha-1
Percentage of tree size available for
woodfuel Psi 53 53 80 80 %
Percentage of tree species available for
woodfuel Psp 43 43 40 40 %
Forest biomass density for trees
available for woodfuel Bw = Ba×Psi×Psp 10 10 15 15 t ha-1 Forest area needed to meet the per
capita demand Fc = Dc/Bw 37 35 201 820 m2
Forest area needed to meet the total
demand Ft = Fc×Nr 34 530 274 2,900 ha
Table 7.4. The estimates of the GLM.
Estimate SE t Pr(>|t|)
Firewood Consumption
Intercept 157.450 111.159 1.416 0.174
Household size -67.796 19.949 -3.398 0.003
Annual income 0.028 0.011 2.525 0.021
Frequency of cooking 183.840 49.449 3.718 0.002
User type (Single-fuel user) 157.585 65.736 2.397 0.028
Charcoal Consumption
Intercept 38.644 34.459 1.121 0.271
Household size -0.349 7.048 -0.049 0.961
Annual income -0.002 0.003 -0.699 0.490
Frequency of cooking 15.672 19.253 0.814 0.422
User type (Single-fuel user) 59.757 22.858 2.614 0.014
GLM: generalized linear model.
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Figure 7.3. Changes in forest area (ha) needed to meet the woodfuel demand at the whole township when the rural population changed from single-woodfuel-users to multiple-fuel-users.
7.5. Discussion
7.5.1. Woodfuel consumption rates in the urban area
There have been previous studies of woodfuel consumption rates in urban area.
Firewood consumption rate in our study was likely within the range of reported values in the other countries, whereas charcoal consumption rates tend to be lower than previous reported values. For firewood, the consumption rate of our study site (217.4 ± 38.9 kg capiata-1 year-1, which is equivalent to 1898.0 ± 506.1 kg household-1 year-1 and 3.8 ± 0.4 kg household-1day
-1) was higher and lower than the rates reported for urban areas of South Africa (1454 kg/household/year) (Shackleton et al., 2007) and of Mozambique (5.47 ± 1.00 kg household
-1day-1) (Brouwer and Falcão, 2004), respectively. For charcoal, the per capital consumption in our study (68.8 ± 11.5 kg year-1 which is equivalent to 1898.0) was approximately about the half of the rates in urban Tanzania (138.6 kg capiata-1 year-1) (Mwampamba, 2007), urban areas in Kenya (130 kg capiata-1 year-1) (Kituyi et al., 2001a) and Kampong Thom Province, Cambodia (120 kg/year) (Top et al., 2003). In addition, in Mozambique, average daily charcoal consumption was 2.69 ± 0.10 kg household-1day-1 (Brouwer and Falcão, 2004)
0 500 1000 1500 2000 2500 3000 3500 4000
0 10 20 30 40 50 60 70 80 90 100
Percentage of the rural population who changed from single-woodfuel-users to multiple-fuel-single-woodfuel-users
Single-firewood-users Single-charcoal-users
Multiple-fuel-users with firewood Multiple-fuel-users with charcoal
Forest area (ha) needed to meet woodfuelconsumtions
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and which is about three times of our results (0.8 ± 0.1 kg household-1day-1 for charcoal).
The reason of consistently lower rate of urban charcoal consumption of our study is not clear and it may be because the charcoal users of our study may consume more other types of energy as compared the cases of the other countries.
The rates of firewood and charcoal consumption in urban area are much lower than those for rural area of our study site (Table 7.3). This is obviously because majority of the woodfuel users in the urban area are multiple-fuel-users (Table 7.2) while only single-fuel-users were found in the rural area by Win et al. (2018c) in chapter 6. The other energy such as electricity plays an important role in the urban area; more than seventy percent of people reported use of electricity for cooking. Even for single-fuel-users, the consumption rates of the urban area (362 ± 107 kg capita-1 year-1 for firewood and 110 ± 18 kg capita-1 year-1 for charcoal) were less than half of those of the rural area. Longer distance from the forest resources may be a reason of the lower consumption rates of urban single-fuel-users since accessibility to the forests considerably influences on consumption rates (Kituyi et al., 2001a; Mushtaq et al., 2014; Win et al., 2018c).
There were some similarities and differences in the GLM results of the consumption rates between the urban area of this study and the rural area by Win et al. (2018c). The households with less members and more frequent cooking tended to have higher firewood consumption rates in both the urban (Table 7.4) and rural areas (chapter 6), and this trend was also found for rural charcoal consumption in chapter 6 (Win et al., 2018c). In contrast, the independent variables other than the user types (single- or multiple users) did not affect urban charcoal consumption rates (Table 7.4). The reason of such differences is not clear, so further analysis with more sample size would be needed since this study only used data from 66 households.
7.5.2. Potential impact of urban woodfuel consumption on forests
It is important to consider the sources, sizes and species of trees used for woodfuel when we evaluate impacts of woodfuel use on forests. In this present study, 61.2 % of firewood consumed was forest-originated green wood > 10 cm diameter, and this ratio is substantially higher than that reported for rural area of our study site in chapter 6 (16.1 %) (Win et al., 2018c). This difference may be because that many (69.1%) of total firewood
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consumed in the urban area was bought and mostly firewood producers for selling tend to cut living trees in forests while in the rural area (chapter 6) only 1.9% of the rural consumption was from buying and most of rural users tends to collect dead wood in forests or cut trees from non-forested areas such as agricultural farm and home garden (Win et al., 2018c).
When we compare the same amount of firewood consumption, the impacts of the household use of firewood on forests in the urban area was larger than that in the rural area.
Regarding solid wood, the per capita consumption rates for firewood (217 kg or 0.31 m3) and for charcoal (293 kg or 0.41 m3) in the urban area were much lower than those in the rural area (780 kg or 1.1 m3 for firewood and 1190 kg or 1.7 m3 for charcoal). This difference is also because of most multiple-fuel-users in the urban area but only single-fuel-users found in the rural area in chapter 6 (Win et al., 2018c). For firewood, per capita demand of forest-originated green wood > 10cm in the urban area (37.6 kg) is similar to that in the rural area (36.0 kg) because lower consumption rate due to multiple-fuel-use may be offset by higher percentage of forest-originated green wood in the urban area (61.2%) than that in the rural area (16%). For charcoal, 100% of wood used for the production are forest-originated green wood with size >10cm in both the urban and rural areas, and thus per capita demand of forest-originated green wood > 10cm is the same to the per capita consumption rates (293 kg and 1190 kg in the urban and rural areas, respectively). Consequently, the estimated areas needed to meet the per capita demand for firewood is also similar between the urban (37 m2) and rural areas (35 m2) while for charcoal, 4-fold more for rural area (820 m2) than for urban area (201 m2). This result indicates that it is crucial to reduce charcoal consumption in the rural area.
Assuming that the numbers of firewood and charcoal users are currently 38.4% and 56.1 % of the total urban population, the estimated areas of forests needed to meet the demand for all the urban villages were 274 ha for charcoal and 34 ha for firewood. The total 309 ha for urban area is equivalent to only 0.3 % of forest area within 5 km distance from the resident areas (115,051 ha) in the township, and it was very small compared with about 3%
(3430ha) estimated for rural area in chapter 6 (Win et al., 2018c). This result suggests that impacts of current woodfuel consumption on forests are likely much more substantial for rural use rather than urban use in the studied township in Myanmar, as opposed from concerns on urban areas in African countries (Arnold et al., 2006; Mwampamba, 2007).
We assumed the “energy ladder” in the rural area, switching from firewood to charcoal, and then concluded that such the “energy ladder” causes higher harvesting intensity,
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resulting in a high risk of further forest degradation. However, the present study suggests that urbanization likely induces an “energy stack” (Van Der Kroon et al., 2013), in which residents employ multiple fuels (among primitive fuels, transition fuels, and advanced fuels) rather than the single-fuel use in the “energy ladder”. This finding is compatible with those from several studies in other countries (Van Der Kroon et al., 2013). We estimated that the forest area needed for woodfuel consumption for all villages in the township would reduce to around 40% if the share of single-fuel users in rural villages deceased and was replaced by multiple-fuel use. This result confirms that the “energy stack” can largely reduce the impact of woodfuel consumption in forests. Such an “energy stack” scenario would be enabled if the Myanmar government achieves the stated energy policy goal of encouraging energy independence, improving hydroelectric sources of supply, expanding the electricity grid to rural areas and promoting energy efficiency (Sovacool, 2013).
