Semi-arid Central Tanzania Research Articles

Analysis of Rainfall and Temperature Dynamics (1981 to 2021) in Semi-Arid Central Tanzania

Analysis of Rainfall and Temperature Dynamics (1981 to 2021) in Semi-Arid Central Tanzania

Modelling Rainfed Pearl Millet Yield Sensitivity to Abiotic Stresses in Semi-Arid Central Tanzania, Eastern Africa

Drought and heat-tolerant crops, such as Pearl millet (Pennisetum glaucum), are priority crops for fighting hunger in semi-arid regions. Assessing its performance under future climate scenarios is critical for determining its resilience and sustainability. Field experiments were conducted over two consecutive seasons (2015/2016 and 2016/2017) to determine the yield responses of the crop (pearl millet variety “Okoa”) to microdose fertilizer application in a semi-arid region of Tanzania. Data from the experiment were used to calibrate and validate the DSSAT model (CERES Millet). Subsequently, the model evaluated synthetic climate change scenarios for temperature increments and precipitation changes based on historic observations (2010–2018). Temperature increases of +0.5 to +3.0 °C (from baseline), under non-fertilized (NF) and fertilizer microdose (MD) conditions were used to evaluate nine planting dates of pearl millet from early (5 December) to late planting (25 February), based on increments of 10 days. The planting date with the highest yields was subjected to 49 synthetic scenarios of climate change for temperature increments and precipitation changes (of −30% up to +30% from baseline) to simulate yield responses. Results show that the model reproduced the phenology and yield, indicating a very good performance. Model simulations indicate that temperature increases negatively affected yields for all planting dates under NF and MD. Early and late planting windows were more negatively affected than the normal planting window, implying that temperature increases reduced the length of effective planting window for achieving high yields in both NF and MD. Farmers must adjust their planting timing, while the timely availability of seeds and fertilizer is critical. Precipitation increases had a positive effect on yields under all tested temperature increments, but Okoa cultivar only has steady yield increases up to a maximum of 1.5 °C, beyond which yields decline. This informs the need for further breeding or testing of other cultivars that are more heat tolerant. However, under MD, the temperature increments and precipitation change scenarios are higher than under NF, indicating a high potential of yield improvement under MD, especially with precipitation increases. Further investigation should focus on other cropping strategies such as the use of in-field rainwater harvesting and heat-tolerant cultivars to mitigate the effects of temperature increase and change in precipitation on pearl millet yield.

Analysis of Intra and Interseasonal Rainfall Variability and Its Effects on Pearl Millet Yield in a Semiarid Agroclimate: Significance of Scattered Fields and Tied Ridges

Establishing food security in sub-Saharan African countries requires a comprehensive and high resolution understanding of the driving factors of crop production. Poor soil and adverse climate conditions are among the major drivers of poor regional crop production. Drought and rainfall variability challenges are not fully being addressed by rainfed producers in semiarid areas. In this study, we analysed the spatiotemporal rainfall variability (STRV) and its effects on pearl millet yield using two seasons of data collected from 38 rain gauge stations scattered randomly in farm plots within a 1500 ha area of semiarid central Tanzania. The STRV effects on pearl millet yield under flat and tied ridge management were analysed. Our results show that seasonal rainfall can vary significantly for neighboring fields at distances of less than 200 m, which impacts yield. The STRV for daily rainfall was found to be more critical than for total seasonal rainfall amounts. Scattering fields can help farmers avoid total harvest loss by obtaining at least some yield from the areas that received adequate rain. The use of tied ridges is recommended to conserve soil moisture and improve yields more than flat cultivation in semiarid areas.

DISSEMINATION AND USE OF INFORMATION ON CLIMATE CHANGE AND VARIABILITY: A CASE STUDY OF FARMERS IN MALUGA AND CHIBELA VILLAGES IN SEMI-ARID CENTRAL TANZANIA

This study was part of broader PhD research which investigated how access to, and use of, information enhances adaptation to climate change and variability in the agricultural sector in semi-arid Central Tanzania. The research was carried out in two villages using Rogers’ Diffusion of Innovations theory and model to assess the dissemination of this information and its use by farmers in their adaptation of their farming practices to climate change and variability. This predominantly qualitative study employed a post-positivist paradigm. Some elements of a quantitative approach were also deployed in the data collection and analysis. The principal data collection methods were interviews and focus group discussions. The study population comprised farmers, agricultural extension officers and the Climate Change Adaptation in Africa project manager. Qualitative data were subjected to content analysis whereas quantitative data were analysed to generate mostly descriptive statistics using SPSS.  Key findings of the study show that farmers perceive a problem in the dissemination and use of climate information for agricultural development. They found access to agricultural inputs to be expensive, unreliable and untimely. To mitigate the adverse effects of climate change and variability on farming effectively, the study recommends the repackaging of current and accurate information on climate change and variability, farmer education and training, and collaboration between researchers, meteorology experts, and extension officers and farmers. Moreover, a clear policy framework for disseminating information related to climate change and variability is required.

Agricultural Commercialization and Adaptation to Climate Change and Variability in Semi-Arid Central Tanzania

Aims: The study was conducted to investigate the implications of smallholder agricultural commercialization on adaptation to climate change in semi-arid central Tanzania. Study Design: Descriptive survey and observational designs were used in this study. Moreover, analytical design was used to analyze the trends of climate and commercialization in the area. Place and Duration of Study: Hembahemba and Manyata villages in Kongwa district, Dodoma region, Tanzania were selected for the study. The study was conducted between October 2012 and October 2013. Methodology: A variety of methods were used in the study including participatory assessment techniques, field visits and household surveys. Primary data collection involved the use of key informant interviews, household questionnaires, focus group discussions and field observations. Secondary data were collected through literature and documentary review. Temperature and rainfall data from 1970 to 2012 were analysed by simple linear regression performed using Original Research Article Chitimbe and Liwenga; JAERI, 3(3): 119-130, 2015; Article no.JAERI.2015.040 120 Microsoft Excel. Non-numeric data were coded and analyzed by Statistical Package for Social Sciences (SPSS). Household Commercialization Index (HCI) was used to analyze levels of agricultural commercialization. Results: The experience of the interviewed respondents on rainfall and temperature trends corresponded to the analysis of climatic data from Tanzania Meteorological Agency (TMA). The analysis indicated an increase of temperature at a rate of 0.0137°C annually for the past 42 years and a decrease of rainfall at a rate of 1.5062 mm annually from 1983 to 2012. However, rainfall decreased more rapidly at a rate of 4.597mm annually between 1995 and 2012, putting agricultural sector into risk. On the other side, agricultural commercialization influenced mechanization and changes of agricultural practices in diverse ways. Changes, such as abandonment of mixed farming and drought tolerant traditional crop varieties exposed the farmers into risks of climatic shocks while changes on tillage practices and crop diversification contributed to adaptation. Conclusion: Taking into account the climatic changes and market forces, it is likely that agricultural diversification can further contribute to resilience.

Facing food insecurity in Africa: Why, after 30 years of work in organic agriculture, I am promoting the use of synthetic fertilizers and herbicides in small-scale staple crop production

Food insecurity and the loss of soil nutrients and productive capacity in Africa are serious problems in light of the rapidly growing African population. In semi-arid central Tanzania currently practiced traditional crop production systems are no longer adaptive. Organic crop production methods alone, while having the capacity to enable food security, are not feasible for these small-scale farmers because of the extra land, skill, resources, and 5–7 years needed to benefit from them—particularly for maize. Maize, grown by 94 % of farmers, has substantial nitrogen needs. The most practical ways of satisfying maize nutrient needs is via integrated soil fertility management, a combination of organic and Green Revolution methods. Maize has been shown in research to outyield the indigenous crops millet and sorghum in nearly all situations including drought. Conservation Agriculture (CA) in Africa has two main categories—organic and herbicide-mediated. The organic version of CA, despite years of promotion, has had a low rate of adoption. Herbicide-mediated zero tillage CA via backpack sprayer can substantially increase conventional maize yields while at the same time nearly eliminating erosion and increasing rainwater capture up to fivefold. Glyphosate herbicide is a non-proprietary product produced in Africa and approved for small farm use. The systemic nature of glyphosate allows the killing of perennial grasses that would otherwise need deep plowing to kill. The rooted weed residues protect the soil from erosion. The risks of glyphosate use are substantially outweighed by the benefits of increased food security and crop system sustainability.

Use of Indigenous knowledge in seasonal weather forecasting in semi-arid central Tanzania

Abstract This article is based on part of findings of a PhD study that was carried out to determine how farmers have used indigenous knowledge (IK) to adapt to climate change and variability in the semi-arid region of central Tanzania. Two villages, Maluga and Chibelela, were used as the case studies. The study applied Rogers’ Diffusion of Innovations theory and model. The study which predominantly adopted a qualitative approach used a post-positivist paradigm. The study population was made up of farmers, agricultural extension officers and the Climate Change Adaptation in Africa project manager. The principal data collection methods were interviews and focus group discussions. The qualitative data collected were subjected to content analysis whereas quantitative data were analysed with the help of SPSS to generate descriptive statistics. The findings revealed that the farmers in the two villages under study perceived conventional information on weather as unreliable and untimely. Consequently, the farmers turned to IK to predict weather patterns and make the necessary farming adjustments. It was established that uncertainty about seasonal weather forecasts was one of the most critical factors which forced farmers to continue using IK. Moreover, farmers’ knowledge of birds, insects, plants, animals, wind direction and astronomical indicators was used to predict weather patterns. The recommendations include the provision of timely and accurate weather forecast information to the farmers to enhance their coping and adaptation strategies under varying climate conditions; and a clear policy framework on the dissemination of information related to weather patterns in rural Tanzania.

Sorghum Yield Response to Changing Climatic Conditions in Semi-Arid Central Tanzania: Evaluating Crop Simulation Model Applicability

Decision Support System for Agrotechnology Transfer (DSSAT) and Agricultural Production Systems SIMulator (APSIM) were calibrated and evaluated to simulate sorghum (Sorghum Bicolor L. Moench) var. Tegemeo under current and future climate in central Tanzania. Simulations for both current and future periods were run assuming present technology, current varieties and current agronomy packages to investigate rain-fed sorghum yield response. Simulations by both crop models using downscaled weather data from eight General Circulation Models (GCMs) under the Coupled Model Intercomparison Project phase 5 (CMIP5) and Representative Concentration Pathway (RCP 4.5) by mid-century show a mixture of increase and decrease in median sorghum yields. Four GCMs project yields to increase by 5% - 23.0% and one GCM show a decrease by 2% - 9%. Model simulations under the remaining three GCMs give contrasting results of increase and decrease. Adjustment of crop duration to mimic the choice of growing local cultivars versus improved cultivars seems a feasible option under future climate scenarios. Our simulation results show that current open-pollinated sorghum cultivars would be resilient to projected changes in climate by 2050s but things seem better with long duration cultivars. We conclude that crop simulation models show their applicability as tools for assessing possible impacts of climate change on sorghum due to agreement in the direction of crop yield predictions in five out of eight selected GCMs under projected climate scenarios. The findings provide useful guidance and motivation to government authorities and development agencies dealing with food security issues to prioritize adaptations policies geared to ensuring increased and sustained sorghum productivity in Tanzania and elsewhere.

Indigenous Knowledge use in seasonal weather forecasting in Tanzania : the case of semi-arid central Tanzania

This paper is based on part of the findings of a PhD study that was carried out to determine how farmers have used indigenous knowledge (IK) to adapt to climate change and variability in the semi-arid region of central Tanzania. Two villages, Maluga and Chibelela, were used as the case studies. The study applied Rogers' (2003) Diffusion of Innovations theory and model. It adopted a predominantly qualitative approach and a post-positivist paradigm. The study population was made up of farmers, agricultural extension officers and the Climate Change Adaptation in Africa project manager. The principal data collection methods were interviews and focus group discussions. The qualitative data collected were subjected to content analysis whereas quantitative data were analysed with the help of SPSS to generate descriptive statistics. The findings revealed that the farmers in the two villages under study perceive conventional information on weather as unreliable and untimely. Consequently, the farmers turned to IK to predict weather patterns and make the necessary farming adjustments. It was established that uncertainty about seasonal weather forecasts is one of the most critical factors which forces farmers to continue using IK. Farmers' knowledge of birds, insects, plants, animals, wind direction and astronomical indicators is used to predict weather patterns. The recommendations include the provision of timely and accurate weather forecast information to the farmers to enhance their coping and adaptation strategies under varying climate conditions; and a clear policy framework on the dissemination of information related to weather patterns in rural Tanzania.

Traditional Tillage Systems as Drought Adaptation Strategies of Smallholder Farmers: The Case of Semi-Arid Central Tanzania

This article presents local knowledge on ecosystem management by analyzing and discussing traditional tillage practices applied by smallholder farmers as a response to drought risks in dryland areas of Mpwapwa District, central Tanzania. Farming activities in the area wholly depend on rain-fed systems. Information from key informants and in-depth household interviews indicate that farmers in this area use three different traditional tillage practices—no-till (sesa), shallow tillage (kutifua), and ridges (matuta). Available information suggests that selection of a particular practice depends on affordability (in terms of costs and labor requirements), perceived ability to retain nutrient and soil-water, and improvement of control of erosion and crop yield. In this area, smallholder farmers perceive no-till practice to contribute to more weed species, hence more weeding time and labor are needed than in the other two practices. The no-till practice also contributes to low soil fertility, low soil moisture retention, and poor crop yield. No plans have been made to introduce irrigation farming in these marginal areas of central Tanzania. Thus, improving the ability of the tillage practices to conserve soil moisture and maintain soil fertility nutrients using locally available materials are important tasks to be carried out. This will ensure the selection of practices that will have positive influence on improved crop yields in the area.

Tillage Practices and Their Impacts on Soil Fertility in Farmer' Fields in Semi-Arid Central Tanzania

We assessed impact of 5 years continuous application of traditional tillage practices (no-till (NT), shallow tillage (ST) and ridging tillage (RT)) applied by smallholder farmers in central Tanzania. Soil samples were collected at two different soil depths to verify farmer' perceptions. At 0–15 cm, ANOVA showed no significant difference (p > 0.05) for tested parameters except total N which was significantly different and rich in NT. Whereas no significant difference were observed for chemical properties analysed at 15–30 cm, percentage clay, silt and sand content were significantly different (p < 0.05) over tillage practices with NT having more silt and clay.

“If only it would rain”: Farmers’ perceptions of rainfall and drought in semi-arid central Tanzania

Farmers in semi-arid East Africa prioritize drought as their major productivity-reducing problem, while scientists identify soil degradation as a major threat. The question that needs to be addressed is how farmers perceive drought. Insight into farmers’ perceptions of drought could be the missing link towards increased and sustainable production. During the period from 2004 to 2006, a study was conducted in Goima Ward, Tanzania. The study included questionnaires with mainly open-ended questions ( N=120), in-depth interviews, group discussions, field visits, picture assignment and 1-day seminar with farmers, extension workers, government officials, and scientists. Farmers saw drought in a broader perspective than that of deficient rainfall. Drought indicators were area-specific. Farmers recognized differences in drought vulnerability between soil types, location and state of land, land management practices and farmer types. Farmers perceived an increased drought risk. Farmers’ perceptions can be related to the scientific concept of agricultural drought. Since the amount of rainfall cannot be influenced, the efficiency of the rains can be a focal point for addressing farmers’ concerns about drought. Any viable strategy to reduce farmers’ vulnerability to drought and to improve productivity should be integrated into farmers’ existing strategies to adapt to and cope with ecological insecurity.

Sustaining water resource use in the degraded environment of the Irangi Hills, central Tanzania

The Irangi Hills in the semiarid central Tanzania are known for their severe land degradation, particularly through soil erosion. This study aims at investigating the dynamics in the local resource management and adaptive farming strategies. A combination of conventional survey methods, participatory analysis, soil description and aerial photo interpretations were used in the analysis of spatial and temporal land-use patterns. Results from the study showed that farmers utilised all possible niches in the landscape with the agricultural practices varying considerably, depending on spatial variations in soil conditions, water availability and retention capacity of the soil. The hard clayey soils were often ploughed at the end of the rainy season, before the soil dried out, to facilitate timeliness of planting in the following growing season, and to enhance water infiltration at the onset of the rainy season. Seasonally waterlogged soils were intensively cultivated and planted late during the growing season, with crops maturing only from groundwater resource. To make effective use of available groundwater resources during the dry season, the droughty and often infertile sands in ephemeral watercourses are used for growing vegetables or sugarcane in sunken holes without additional fertilisers/manure. This suggests that the crops grown obtain sufficient nutrients only from groundwater resources. However, the sustainability of cultivation in these ephemeral waterways is still questionable.

Optimising the quality and biomass production of maize stover tops for stall-fed dual purpose dairy cows in semiarid central Tanzania

Maize was grown to investigate maize stover tops production, conservation methods and feeding value, when harvested at different intervals after grain maturity. It was either planted as a pure stand or intercropped with lab lab plants. Maize tops were harvested after grain maturity (stage1) and at 3, 6, 9 and 12 weeks thereafter (stages 2, 3, 4 and 5). The tops were stacked in the field (A), laid down in the field (B), or stored in a shed (C). A feeding trial with 12 cows was carried out to investigate DM intake, milk yield and composition. The cows were fed grass hay mixture (T1), green maize tops (T2), and maize stovers after grain harvest (T3) supplemented with lab lab forage and maize bran. Harvesting stages 1 and 2 yielded more tops (1.5 and 1.4 tonne/ha, respectively), higher crude protein, digestibility and metabolizable energy, lower acid and neutral detergent fibre than 3 to 5. The potential nutritive values were higher in maize tops stored in C than B and A. Total intake and milk yield were higher on T1 and T2 than on T3 (8.06 and 7.98 vs. 6.25 kg DM/day) and (5.05 and 5.02 vs. 4.4 kg/day), respectively. Milk components were similar. Harvesting stages 1 and 2 provided larger amounts of tops of high potential nutritive value than stages 3 to 5. Storing in a shed conserved nutritive value of green maize fodder better than laying and stacking methods. It compared well with grass hay mixture for milk production when supplemented with lab lab forage.

Seed rain and its role in the recolonization of degraded hill slopes in semi-arid central Tanzania

Seed rain and its role in the recolonization of degraded hill slopes in semi-arid central Tanzania

A stall‐feeding management for improved cattle in semiarid central Tanzania: factors influencing adoption

AbstractThis study's objectives were to determine factors influencing smallholder farmers' adoption of a stall‐feeding management system for improved dairy cattle in semiarid Tanzania and other related technology packages, Heckman's two‐stage procedure was used to determine factors influencing participation in the project and the adoption of recommended management practices. Stall‐feeding technology is Jocularly attractive to those households with fewer resources particularly those that are female headed. Wealthier farmers, as measured by area of land cultivated, are less likely to adopt the stall‐feeding technology. Household labour is found to be important in determining the degree to Which the technology and associated management practices were adopted. Age of the household head has a positive impact on the size of the Intensive feed gardens. Different measures of extension‐related contact are significant in influencing the potential lor adopting stall‐fed technology, the number of stall‐fed cattle kept, the probability of growing water melons, and the size of intensive feed gardens. The implications are that research and extension messages with reference to the stall‐feeding management system need to be targeted to specific types of households (e.g., female farmers, those with children to provide labor, and limited resource farms). This supports the notion that technology development and dissemination need to be sensitive not only to the characteristics of the biophysical environment but also to the socioeconomic environment, which is often neglected. The study also demonstrates that in the poorer parts of the world where land is very limited, a strategy for improving ecological sustainability can be linked closely to one for increasing agricultural productivity.

A stall-feeding management for improved cattle in semiarid central Tanzania: factors influencing adoption

Abstract This study's objectives were to determine factors influencing smallholder farmers' adoption of a stall-feeding management system for improved dairy cattle in semiarid Tanzania and other related technology packages. Heckman's two-stage procedure was used to determine factors influencing participation in the project and the adoption of recommended management practices. Stall-feeding technology is particularly attractive to those households with fewer resources particularly those that are female headed. Wealthier farmers, as measured by area of land cultivated, are less likely to adopt the stall-feeding technology. Household labour is found to be important in determining the degree to which the technology and associated management practices were adopted. Age of the household head has a positive impact on the size of the intensive feed gardens. Different measures of extension-related contact are significant in influencing the potential for adopting stall-fed technology, the number of stall-fed cattle kept, the probability of growing water melons, and the size of intensive feed gardens. The implications are that research and extension messages with reference to the stall-feeding management system need to be targeted to specific types of households (e.g., female farmers, those with children to provide labor, and limited resource farms). This supports the notion that technology development and dissemination need to be sensitive not only to the characteristics of the biophysical environment but also to the socioeconomic environment, which is often neglected. The study also demonstrates that in the poorer parts of the world where land is very limited, a strategy for improving ecological sustainability can be linked closely to one for increasing agricultural productivity.

Managing food shortages in Central Tanzania

Famine prevention and mitigation strategies have become an established area of interest for researchers concerned with food insecurity. Studies often focus on one famine event and the coping strategies immediately preceding or accompanying it. By contrast, this case study adopts a long-term perspective and depicts the changes of indigenous and exogenous famine-coping strategies among the Gogo, an ethnic group in semi-arid central Tanzania, over a time-span of one and half centuries. By doing so, this paper tries to give insights into the continuity and adaptability of human reactions to a persistent problem under changing socio-economic circumstances.

Interpretation of geomorphology and vegetation of LANDSAT satellite images from semi-arid central Tanzania

D. Johansson & L. Strömquist 1978. Interpretation of geomorphology and vegetation of LANDSAT satellite images from semi-arid central Tanzania. Norsk geogr. Tidsskr. Vol 32, 49–54. Oslo. ISSN 0029-1951. Detailed maps of geomorphology and vegetation have been produced by interpretation of LANDSAT satellite images from a semi-arid area in central Tanzania. The methods of analysis are discussed with reference to land forms, geomorphological process activity, soils, and vegetation. A correlation between the grey tones (on band 5) and their associated vegetation types, soils, and geomorphology is established.

The Role of Sown Pastures in Semi-Arid Central Tanzania

The Role of Sown Pastures in Semi-Arid Central Tanzania