Climate smart Agricultural practises and Food security: A case of Mbeya and Songwe regions in Tanzania

Abstract

Although Climate Smart Agriculture Practises (CSA-practises) have been promoted and implemented in the Tanzania, but usage of CSA-practises is still low while their impact on food security is not well documented, especially when used in combinations. This study examined the usage of different CSA-practises and their impact on food security among farming households in Mbeya and Songwe Regions in Tanzania with specific objectives to; a) assess the usage and intensity of using multiple CSA-Practises by farming households b) assess the determinants of using combinations of CSA-Practises by farming households c) evaluate the impact of using combination of crop rotation, residue retention and intercropping on food security d) evaluate the impact of using combination of organic manure, irrigation and drought tolerant maize seeds on food security and e) evaluate the impact of climate-smart irrigation practise on food security. Multistage sampling technique was employed in sampling 1443 farming households. A household survey was conducted whereby the primary data were collected using a structured questionnaire. The Household Dietary Diversity Score per Adult Equivalent Unit (HDDS/AEU) and Food Variety Score per Adult Equivalent Unit (FVS/AEU) were used as indicators to measure household food security. To assess the usage of the multiple CSA-practises a multivariate probit model was used while the ordered probit model was used to examine the intensity of using CSA-practises. A multinomial probit model was employed to estimate the factors influencing the use of combinations of CSA-practises (i.e. crop-rotation, crop residue retention and intercropping). To examine the impact of using a combination of CSA-practises (crop rotation, residue retention and intercropping), a multinomial endogenous switching regression model was employed. Furthermore, the study employed a multinomial endogenous treatment effect regression model to evaluated the impact of using organic manure, drought-tolerant maize seeds. and irrigation on food security. Furthermore, endogenous switching regression model was employed to evaluate the impact of using climate smart irrigation on food security. The evaluation methods used in this study are appropriate in the analysis of the control for both observed and unobserved heterogeneity. Other evaluation approaches such as propensity score matching and inversely probability-weighted regression (IPWR) can only control observed heterogeneity which leads to unbiased estimates. The results from multivariate probit (objective one) showed that the use of CSA-practises was positively influenced by gender of the head of the household, farm size, education of the head of household, location, size of the household, occupation, and farmer organizations membership. Moreover, it was found that the use of drought-tolerant maize seeds and crop rotation was positively associated while the use of a residue-retention and crop-rotation in combination, the use of organic manure and crop-rotation, combination of intercropping and residue-retention and the use of intercropping and organic manure were significantly and positively associated at significant level 1 %. This implies that farming households consider these combinations as complements. The study examined the determinants of farm households’ decision to use combinations CSA- practises (objective two) and found that production diversification, gender and livestock ownership were positively and significantly influence the usage of combinations of residue- retention and intercropping. In addition, education level and gender of the head of the household were positively and significantly affect in the usage of combination of crop rotation, crop residue and intercropping This comprehensive study is significant for finer understanding of the synergistic effect of interrelated CSA-practises. The result for objective three found that usage of CSA-practises depends on either it is used in isolation or in combinations, and the usage of these CSA-practises significantly increase food variety score per adult equivalent unit when used either singly or jointly. Furthermore, the use of intercropping in isolation show the highest food variety scores per adult equivalent unit among all the possible combinations of CSA-practises. Moreover, the use of crop rotation in isolation also showed a high pay off after intercropping followed by a joint combination of crop rotation and residue retention. Thus, the usage of a combination of crop rotation, intercropping and crop residue retention was found to be the best food security portfolio. Results from objective four found that the characteristics of the household, plot characteristics and institutional characteristics (e.g access to extension services) influences the usage of a different combination of CSA-practises. The study also found that the highest payoff of food security could be achieved when CSA-practises are used in combination than in isolation. The combination of drought-tolerant maize seeds and irrigation gave higher payoff than the combination of all three CSA-practises. Finally, the findings from objective five showed that radio ownership, education of the household head, farm experience, production diversity and livestock ownership were the determinants of using irrigation in the study area. The average treatment effect of the treated (ATT) and the average treatment effect of untreated (ATU) were positive and highly significant for irrigators and non-irrigators. That is, the use of irrigation as a CSA-practise has improved food security of the farming households. It is recommended that, inorder in order to enhance the usage of CSA-practise, policy makers and local government authorities should target equipping extension workers and other agricultural practitionners with adequate items of infrastructure that enable their easy movement to the farmers. In addition, more more extension agents should be trained and deployed in the country to reduce the workload of the limited number of extension officers available inoder to improve agricultural productivity and food security The study calls for policy makers on policies and plans that promote CSA-practises as a combination, including other interrelated practises which upscaling CSA-practises usage. Furthermore, there is a need to promote the usage of CSA-practise in isolation or in combination. In addition, the study suggests that based on the practises considered in this study, usage of a combination of various practises results in better food security compared to the usage of these practises individually. This suggests that agricultural practitioners should promote combinations of CSA-practises to improve food security in the farming households. It is recommended that policymakers should consider rehabilitating the existing irrigation schemes while constructing new irrigation schemes to widen the impacts of irrigation to household food security. However, despite the positive impact of irrigation, it is recommended that other irrigation practises such as drip irrigation, sprinkler irrigation should be used in the areas where construction of small-scale irrigation is not possible.