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Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 ISSN 1816-8272 Copyright © 2015 SAPDH Impact Assessment of Climate Change on the Livelihoods of Pastoral Communities in Sudan’ Butana Region: A Multidimensional Tradeoff Analysis Abdelhamed M. Magboul1, Abbas E. M. Elamin1*, Imad-eldin A. Ali-Babiker2, Abdelmotalib A. Ibnoaf3 and Faisal M. El-Hag2 Abstract This study aimed at assessing the impact of climate change on the livelihoods of pastoral communities in Sudan’ Butana Region. Emphasis was put on the forecasted climate factors such as annual rainfall, minimum and maximum monthly temperatures and their impacts on the grazing system, milk productivity and livelihoods. Three States; Gadarif, Gezira and Khartoum states, out of five states constituting Butana region were chosen. A comprehensive questionnaire and farm survey were conducted in 2013. About 203 pastoralists’ households, 100 from Gadarif, 53 from Gezira and 50 from Khartoum were chosen and interviewed. Simple and multiple linear regression was used to assess the impact of the climate factors on milk productivity. The forecasted value of milk productivity in 2030 was used as a livestock productivity parameter in Tradeoff Analysis model for Multi-Dimensional Impact Assessment (TOA-MD) to assess the impacts of climate change on the livelihoods of pastoral communities. Results showed that Gezira State was mostly suffering from climate variability and change, as reflected in significant increases in minimum and maximum monthly temperatures and significant decrease in annual rainfall. This negatively affected rangelands productivity, grazing systems, with significant reduction in animal productivity. Monthly minimum and maximum temperatures had the highest effect on milk productivity than that of annual rainfall. The Gedarif expansion in Butana was considered as the part mostly suffering from high losses in forecasted milk productivity by 2030 accompanied by high losses in forecasted pastoralist’ income. It was recommended that urgent intervention to rehabilitate rangelands, encourage pastoralist to change their herd structure into productive stock and keep sheep or goats in the herd composition should be advocated. Keywards: Climate Change, Multidimensional Tradeoff, Pastoral, livelihoods. Introduction Livestock production is an important component in the Sudanese economy. Animal wealth was responsible for 19.3% of the GDP and over 80% of rural households in Sudan depend on both pastoral and agricultural activities for their livelihoods (MFNE, 2005). Sudan ranks top in terms of livestock population in the Arab World and comes second to Ethiopia among the African countries. Livestock population was estimated at about 103 million heads (Osman et al., 1 Planning, Monitoring and Evaluation, Agricultural Research Corporation (ARC), Wad Medani, Sudan, *Corresponding Author email: [email protected]. 2 Dryland Research Centre (DLRC), Agricultural Research Corporation (ARC), Soba, Khartoum, Sudan. 3 Faculty of Commerce, Economics and Social Studies, Al Neelain University, Khartoum, Sudan. 62 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 2012). Those include 39, 30, 29 and 4 million heads of sheep, goats, cattle and camels, respectively (MAF, 2011). Within the geographical distribution of total livestock in the country 7.2, 5.3, 4.7, 2.3 and 1.3 million are found in the Gezira, Kassala, Gadarif, Nile River and Khartoum states, respectively. These five states sharing the Butana region contribute about 20.7 million heads (about 20% of the total animals in the country, Table 1). In addition, Butana region hosts approximately 8.2 million heads of livestock during the rainy season. Table 1: Total Livestock populations (million heads) in the states sharing the Butana region State Cattle Sheep Goats Camels Totals Gezira 2.40 2.50 2.10 0.12 7.20 River Nile 0.08 1.01 1.20 0.01 2.30 Khartoum 0. 25 0.44 0.64 0.001 1.30 Kassala 0.96 2.02 1.67 0. 67 5.30 Gadarif 1.04 2.14 1.06 0. 33 4.65 Totals 4.80 8.08 6.71 1.15 20.74 Country’s Total 29.4 39.14 30.45 4.62 103.57 Source: Osman et al., 2012 According to satellite images, the total area of the Butana is about 81,567 km², of which 62% is located in Gadarif and Nile River States. About 21% of the Butana area is under cropland, 41% under rangeland cover and about 29% is bare land, which are desert and semidesert areas. About 63% and 24% of Butana bare land is in the Nile River and Kassala States, respectively (Table 2). Fig. 1 shows the agro-climatic zones of the Butana region by State. Table 2. Total area, land use (1000 km²) and % share of each state in Butana area Gadarif Gezir Kassala Khartou River Total land a m Nile use Bare land 0.69 0.26 5.65 2.19 14.91 23.64 (29%) Cropland 10.11 1.98 0.52 3.5 1.03 17.11 (21%) Grassland 12.98 4.31 5.74 4.40 5.64 34.92 (41%) Tree 3.86 0.74 0.66 1.45 1.4 10.30 (9%) cover Total 27.63 7.29 11.97 11.53 23.06 81.48 land use (34%) (9%) (15%) (14%) (28%) (100%) Total 27.63 7.31 12.00 11.56 23.07 81.57 Butana (34%) (9%) (15%) (14%) (28%) (100%) area Source: Osman et al., 2012 Copyright © 2015 SAPDH ISSN 1816-8272 63 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Figure 1. Butana region Climate change and variability is a predominant phenomenon in semidesert, arid and semiarid zones and droughts are becoming more frequent and more severe. Since the early 1980s, due to the reduction in the quantity and uneven distribution of the rainfall, there is an observed fluctuation of the rainfall, long dry spells, drop in relative humidity and rise of temperature. Elhag (2006) stated that Gezira and Khartoum states were subjected to a significant reduction in their monthly and annual rainfall during the period 1996-2006. A consensus clearly emerged among pastoralists in the region that climate has been changing over the past few decades and has adversely affected the productivity of Butana's rangelands. This has resulted in the steady deterioration of both the productivity and biological diversity of the Butana rangelands. Furthermore, Butana hosts other pastoralists from drought-affected areas in other parts of the Sudan. This has intensified pressure on its fragile and deteriorating resource base and further exacerbating the vulnerability of its pastoralists. This study attempted to assess trends and changes in climate factors such as annual rainfall, minimum and maximum monthly temperatures over time in Butana region, impacts of climate change on the grazing system and animal productivity and on livelihoods of the pastoral communities in Butana area. Materials and Methods Site selection and data collection: Three States namely; Gadarif, Gezira and Khartoum were chosen out of the five States constituting Butana area (Figure 1). Gezira State had the highest share in almost all species of animals, about 35% of animals in Butana region, and it is the most affected area by climate change as demonstrated by the decreasing trend of rainfall and rise of temperatures over the 64 Copyright © 2015 SAPDH ISSN 1816-8272 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 last five decades. It is worth mentioning that Gezira and Gadarif contribute about 57% of the total animal wealth in Butana region. Khartoum represented the second most-affected area by climate change. Gadarif ranks second in terms of cattle and sheep but with less camels and goats compared with Kassala State. A comprehensive questionnaire and a farm survey were conducted in 2013 under the project entitled “Enhancing Climate Change Adaptation in Agriculture and Water Resources in the Greater Horn of Africa” (ECAW). About 203 Pastoralists households, 100 from Gadarif, 53 from Gezira and 50 from Khartoum were directly interviewed. Regression analysis: Simple regression analysis was used to estimate the trend of the historical climate data to detect whether there is a climate change in the Butana region as postulated by annual rainfall and monthly minimum and maximum temperatures during the period 1961-2013 recorded in five weather stations in Butana region. The linear trend is simply represented by the following equation: Where: Ty = quantity of the climate variable in question i.e., annual rainfall, minimum or maximum monthly temperature in the main weather stations in Butana region. a = intercept or estimated value when x equals to zero b = slope of the line or average change in Y per unit of time x = time factor in years from 1961 to 2013 used to forecast the estimated values of rainfall and temperatures into 2030. Again, a multiple linear regression was used to assess the impact of the climate factors on annual milk productivity per unit of four animal species in the three States of the study area. The multiple regression equation is expressed as follow: Where y is the annual milk productivity, i represents the three chosen States namely Gadarif, Gezira and Khartoum, j is the observations within each state, represent the coefficients of the variables, represents the intercept term, and ε is an error term. T and R represent the historical data of temperature and rainfall in the Butana states, which are used to forecast the estimated value of milk productivity per unit for the four animal species in 2030 and then used the forecasted livestock productivity in Tradeoff Analysis model for Multi-Dimensional Impact Assessment (TOA-MD). TOA-MD model: The development and application of relatively simple and reliable methods for assessing the impacts of climate change at the agricultural system and/or household level are needed to provide timely recommendations on the potential impacts of alternative technologies and policies. This study used the TOA-MD impact assessment model (Antle and Valdivia 2006; Antle and Ogle, Copyright © 2015 SAPDH ISSN 1816-8272 65 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 2011; Antle, 2011). The model uses statistical description of a heterogeneous farm population to simulate adoption and impacts of a new technology or change in environmental conditions (Seth, 2012). TOA-MD model was used to assess the impact of technology and climate changes using economic, environmental and social indicators. Claessens et al. (2012) pointed that this model has been used for the analysis of technology adoption, payments for environmental services and set up and interpreting of climate change applications. The model simulates technology adoption with associated economic, environmental and social outcomes in a heterogeneous farm population for regional impact assessment. The methodology uses the surveys, experimental and modeled data to assess simulated management practices that are typically available in countries where semisubsistence systems are important, combined with future socio-economic scenarios based on new scenario pathway concepts being developed by the climate change and impact assessment modeling communities (Hugo, 2011). The model includes the following parameters: Population, which targets the pastorals households in Butana region. About 203 respondents from three States (Gedarif, Gezira and Khartoum) out of five stretching into the Butana region. Systems scenarios: where system1 describes the current economic situation of pastoralists, which refers to base climate and base technology, and system2 describing a changing economic situation of pastoralists in the future (in 2030) with reference to change in climate and base technology. The model captured the adoption rate of those pastoralists who continue using the existing technologies of 2012 in the future (2030) despite changes in climate. Strata: three strata, 1, 2 and 3 target the pastoralists in Gadarif, Gezira and Khartoum States with 100, 53 and 50 sampled respondents, respectively. Subsystems: include types of livestock activities; cattle, sheep, goats and camels. Source of data for system1 was the survey data while the data input for system2 was the projection with respect to the change in milk production due to change in climate factors. Types of data: included farm household data such as area/ha, farm size in ha, family size, average milk production in liters, prices of milk in SDG/liter at the current price and cost data (average variable costs), standard deviation of net return from livestock; and an outcome variable represented by a poverty line of USD 1/person/day. Outcomes variables and indicators: These included poverty rate, defined as the percentage of farm population living on less than USD 1 per day, net loss, defined as the percentage of farm income losses as a result of climate change impacts, and the adoption rate, defined as the number of households or the percentage of farm population from the sample continuing to adopt the prevailing technology. The model hypothesizes that only milk productivity will be affected as a result of climate change while the herd size, operation costs and farm size will remain the same during the period 2012 to 2030. TOA-MD is used as a climate impact assessment tool to measure: a) the impact of climate change without adaptation, i.e., assuming all farmers use the base technology (system1) or the impact of climate change, when farmers choose 66 Copyright © 2015 SAPDH ISSN 1816-8272 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 whether to adopt the adapted technology under the perturbed climate. In this respect, a comparison was made between pastoralists' economic and social situations under public rangeland and the prevailing technology options on the one hand, and facilities provided by the Butana Development Agency (BDA) to develop the local public rangelands, on the other hand. This included establishment of small protected grass areas to use in the dry season, reseeding of some preferred grasses and water harvesting techniques. There is no definite farm size for trans-humans whereby animals are predominantly grazed in public rangelands. For this reason, returns and costs were calculated on the basis of herd size and then converted to per farm size based on the estimated areas surrounding the pastoralist villages. It is also likely that the impact of climate change on productivity is underestimated because the effects of increasing climate and weather variability have not been included, and this is one of the biggest constraints in the rain-fed agriculture. Results and Discussion Results showed that Gezira state was subjected to significant reduction in monthly and annual rainfall during the period 1961-2013. This indicated that Gezira state was the state mostly affected and impacted by climate change. With the exception of Gadarif, which was subjected to non-significant increases in the annual and monthly rainfall, other states were subjected to non-significant decreases in the annual and monthly rainfall (Table 3). With respect to temperatures, the five states were subjected to a high significant increase in winter (November to February) minimum temperatures with variable changes in summer and autumn temperatures. The River Nile state recorded insignificant increase in summer (March - June) minimum temperature while, along with Gedarif, recording rising minimum temperatures in autumn (Table 4). Moreover, the Gezira, Gedarif and the River Nile states were subjected to highly significant increases in the maximum temperature during the three seasons; summer, winter and autumn. Kassala and Khartoum, on the other hand, were subjected to significant increases in maximum temperature during winter (Table 5). Table 3. Trends of the annual and monthly rainfall and their significance levels Location Annual rainfall Monthly rainfall Trend P-value Trend P-value ns -0.136 0.128ns Khartoum -1.226 0.128 Kassala -0.109 0.803ns -0.047 0.811ns Gezira -1.761 0.016* -0.22 0.016* ns 0.180 0.104ns -0.037 0.611ns Gadarif 1.623 0.104 River Nile -0.260 0.611ns ns = not significant; * = significant (p = 0.05) Copyright © 2015 SAPDH ISSN 1816-8272 67 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Table 4. Trends of minimum temperature and their significance levels Minimum temperature State Summer Winter Autumn Trend P-value Trend P-value Trend P-value Khartoum state 0.030 0.000** 0.058 0.010** -0.023 0.167ns Kassala state 0.025 0.004** 0.039 0.000** 0.014 0.054ns ns Gezira state 0.013 0.059 0.047 0.003** -0.006 0.520ns Gadarif state 0.033 0.000** 0.031 0.000** 0.024 0.000** River Nile state 0.012 0.09 ns 0.058 0.01** 0.015 0.008** ns = not significant; *’** = significant (p = 0.05,0.01) Source: calculated by author Table 5. Trends of maximum temperature and their significance levels State Maximum temperature Summer Winter Autumn Trend P-value Trend P-value Trend P-value Khartoum state -0.023 0.316ns 0.089 0.01* -0.064 0.037* Kassala state 0.011 0.077ns 0.024 0.010* -0.007 0.589ns Gezira state 0.026 0.000** 0.036 0.000** 0.024 0.004** Gedarif state 0.034 0.000** 0.029 0.000** 0.031 0.000** River Nile state 0.032 0.000** 0.032 0.000** 0.036 0.000** ns = not significant; *,** = significant (at p = 0.05, 0.01) The amount of milk per each species of animal during the period 1961-2013 (FAO, 2006 and survey data, 2013) for the three States; Gedarif, Gezira and Khartoum was regressed on the amount of annual rainfall and minimum and maximum monthly temperature for the same period to trace the effect of these climatic factors on the grazing system reflected in milk productivity. Monthly maximum and minimum temperatures affected milk productivity more than the annual rainfall. This was reflected by the higher negative coefficients of monthly maximum and minimum temperatures compared with the coefficients of annual rainfall (Table 6). Gedarif was the state with highest suffering from increases in minimum and maximum temperatures. In spite of a rising, though insignificant, forecasted annual rainfall, Gedarif has encountered high losses in forecasted milk productivity by 2030 as a result of the impacts of these climate factors (Tables 6 and 7). Annual milk production in Gedarif in 2030 is expected to decrease to 86%, 93% and 99% for sheep, goats and camels, respectively, from its base-system level in 2012 as a result of climate change, although, cattle milk is expected to increase to 102%. In the Gezira, milk production is expected to decrease to 72% and 87% for sheep and goats, respectively of the base-system levels, but milk productivity will simultaneously increase to 107% and 101% for cattle and camels, respectively. Production of milk in Khartoum will witness increases to 104%, 115% and 101% for sheep, cattle and camels respectively, but it will decrease to 96% for goats. 68 Copyright © 2015 SAPDH ISSN 1816-8272 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 The forecasted minimum temperatures depict increases by 5%, 4% and 3% by 2030 in Gedarif, Gezira and Khartoum States, respectively, over their base-period levels. Annual rainfall is also forecasted to increase by 17% in Gedarif (102.84mm) while it would decrease to 60.8% (-139.9) and 52.4% (-89.12mm) by 2030 in the Gezira and Khartoum States, respectively (Table 7). The simulation model showed large negative impacts of climate change on the milk productivity in Butana region as demonstrated by high income declines of the respondent herders by 2030 due to reduction in milk production (Table 8). Increased severity of climate factors (minimum and maximum temperatures) and the relatively high operating costs of animal grazing and drinking-water provision had resulted in high positive annual losses in net income in 2030 (SDG1445.56 and SDG282.16 thousands in Gedarif and Gezira). Further, there were positive annual net losses in farm income (616SDG and 2.3 thousands in Gedarif and Gezira) and annual net losses in incomes as a percent of mean net farm returns (23.08% and 9% in Gedarif and Gezira). On the other hand, Khartoum recorded negative annual net losses for the same items. These findings indicated that Khartoum State would gain under climate change situations due to the combination of insignificant change in climate factors (maximum and minimum temperatures) and cost-effective animal production (Table 8). Table 6. Estimated coefficients for milk productivity for the four animal species in the three states Animal species Gedarif Coefficient Significant Camels Constant 236.62 0.000** Maximum temperature 0.041 0.392 ns Minimum temperature 0.076 0.867 ns Annual rainfall 0.001 0.725 ns Cows Constant 2154.27 0.000** Maximum temperature -16.04 0.252 ns Minimum temperature -48.65 0.000** Annual rainfall -0.083 0.078* Goats Constant 743.38 0.002** Maximum temperature 4.52 0.607ns Minimum temperature -35.16 0.000 ** Annual rainfall -0.068 0.021* Sheep Constant 671.26 0.000** Maximum temperature -11.16 0.097* Minimum temperature -9.91 0.094 * Annual rainfall 0.011 0.248 ns ns = not significant; *,** = significant (p = 0.05,0.01) Copyright © 2015 SAPDH ISSN 1816-8272 69 Gezira Coefficient Khartoum Significant Coefficient Significant 236.59 0.447 0.085 0.002 0.000** 0.416ns 0.827 ns 0.411 ns 237.09 0.37 -0.34 -0.003 0.000** 0.268 ns 0.909 ns 0.285ns 2452.75 -50.7 -7.24 0.157 0.000** 0.000** 0.580ns 0.072 * 1764.90 -23.04 -19.06 0.032 0.000** 0.082* 0.098 * 0.781 ns 1063.44 -31.43 8.56 0.051 0.000** 0.000** 0.276 ns 0.307 ns 787.91 -9.67 -14.97 0.004 0.003** 0.179 ns 0.023 ns 0.952ns 1051.23 -32.71 9.48 0.045 0.000** 0.000** 0.172 ns 0.236 ns 825.41 -13.30 -12.54 0.009 0.001** 0.043 * 0.034 * 0.605ns Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Table 7. Summary of the average data used in the TOA-MD sensitivity and scenario analysis Table 8. Impacts of climate change on Pastoralists in Butana area (losses and gains in SDG/year) Items Total gains in income of respondent herders Total losses in income of respondent herders Net losses income of respondent herders Gains in farm income Losses in farm income Net losses in farm income Gains in incomes as a percent of mean net farm returns Losses in incomes as a percent of mean net farm returns Net losses in incomes as a percent of mean net farm returns Source: TOA-MD model results Gedarif 801.12 2246.67 1445.56 3.41 9.57 6.16 12.79 35.87 23.08 Gezira 624.21 906.36 282.16 5.10 7.40 2.30 19.90 28.90 9.00 Khartoum 457.25 335.30 -121.95 3.78 2.77 -1.01 29.42 21.57 -7.85 (Herders income in 000 SDG); USD 1 = SDG 5.7 Results of the analysis showed the simulated adoption rate of prevailing technologies in grazing animals and using public rangelands in Butana area under the situation of prevailing climatic conditions (System 1) and that of climate change (System 2) as a function of the opportunity cost of changing from System 1 to System 2. The rate that would occur if pastorals are behaving economically rational and maximizing expected returns to their rangelands near their villages (farms) is the point where the curves crossed the horizontal axis. The simulation results designated adopters at 35.3% out of the sampled respondents of the population of pastoral households (Fig.2). Copyright © 2015 SAPDH ISSN 1816-8272 70 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Fig. 2. Adoption rate and opportunity cost of prevailing technologies. The results provide predicted annual net returns per farm in SDG in relation to the adoption rate of available technologies in grazing animals and using the public rangelands in Butana region under the situations of base and change climate. The baseline poverty rates were at the zero adoption rates. However, the annual net return per farm would decrease from 23.913 to 23.58 thousand SDG under climate change at the economically efficient rates of adoption (Figure 3). Fig. 3. Net returns per farm versus adoption rate of prevailing technologies NRFM1_A = Net returns per farm for system1: with animal production at the base climate situations. NRFM2_A = Net returns per farm for system2: with animal production under changing climate NRFM_A = Net Returns per farm for systems 1& 2: with base animal production methods and climate change situation. Copyright © 2015 SAPDH ISSN 1816-8272 71 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Results of the analysis depict predicted poverty rates as a percentage of the respondent pastorals' households in relation to the adoption rate of prevailing technologies in grazing animals using the public rangelands in Butana area under the situations of base changing climate. Taking the baseline poverty rates at zero adoption rates, the poverty rate at a poverty line of USD 2 per person per day would increase from 43.9% to 71.4% of the respondent pastoralists of Butana region under climate change situations and economically efficient rates of adoption (Figure 4). Fig. 4. Poverty rate and adoption rate of prevailing technologies POVERY1_A = Poverty rate for system1: when animal production at the base climate situations. POVERT2_A = Poverty rate for system2: when animal production under change climate situations. POVERTY_A = Poverty rate for system 1&2: when animal production at the base and under change climate situations. Conclusions The Gezira part of Butana was the area mostly suffering from both climate variability and climate change. This was manifested as significant increases in minimum and maximum monthly temperatures, and a significant decrease in annual rainfall with negative impacts on public rangelands’ productivity and the grazing system leading to a highly significant reduction in animal production. Much higher effect of monthly minimum and maximum temperatures on milk productivity than that of annual rainfall was depicted. The Gedarif State part of the Butana region was the mostly suffering from high losses in forecasted milk productivity by 2030 accompanied by high losses in forecasted pastoralist’ income as a result of the impact of rising temperatures despite some increase in rainfall. Therefore, urgent intervention to rehabilitate rangelands, encourage pastoralist to improve their herd structure to favor productive animals and to diversify their herd through keeping sheep or goats should be undertaken. Copyright © 2015 SAPDH ISSN 1816-8272 72 Magboul et al., Sudan Academy of Sciences Journal-Special Issue (Climate Change), Vol. 11 , 2015, 62-73 Acknowledgements This work was part of the Project “Enhancing Climate Change Adaptation in Agriculture and Water Resources in the Greater Horn of Africa” (ECAW) which was funded by the International Development Research Center (IDRC) Grant No. 106552-003. The advice of Dr. Antle, John M. of Oregon State University and Dr. Roberto Valdivia of Montana State University is highly appreciated. References Antle, J.M. 2011. “Parsimonious Technology Impact Assessment.” American Journal of Agricultural Economics. Vol 93(5): 1292-131. Antle, J.M, S. Ogle. 2011. “Influence of Soil C, N2O and Fuel Use on GHG Mitigation with No-till Adoption”. Climatic Change. Vol. 111:609-625. 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