The Impact Of Climate Change To Smallholder Farmers And Adaptation Strategies: The Case Of Traditional Irrigation Farming Systems In West Usambara Highlands

BSTRACT

This study aimed at assessing the impact of climate change on traditional irrigation

farming systems and adaptation strategies was conducted in Lushoto District. The

specific objectives were to establish the trend and magnitude of climate change in

the study area for the past 30 years (1985-2014), to assess the impact of climate

change on crop yield in Ndiwa and Chamazi traditional irrigation farming systems,

to analyse the way traditional irrigation farmers‘ adapt to climate change and to

develop decision guide for adaptation to climate change in traditional irrigation

farming systems. A cross-sectional explanatory research design encompassing both

purposive and systematic random sampling was adopted for this study. The study

sample comprised with 380 households, 48 members of Focus Group Discussion

(FGD) and 15 key informants. Primary data from household heads and key

informants were collected through questionnaire survey, FGDs, interviews and the

researcher‘s observations while secondary data were collected through documents

reviews including annual reports from District Agriculture Irrigation and

Cooperative Offices and weather reports of the study area for the past 30 years from

Tanzania Meteorological Agency (TMA). Descriptive statistics such as mean,

frequency and percentages were computed to establish the trends and magnitude of

climate change using SPSS and MS-Excel programs. Cross tabulation between

rainfall and crop yield trends was used to establish the impact of climate change on

crop yields.Descriptive statistics such as mean, frequency, percentages and Analytic

Hierarchy Process (AHP) analysis were performed to identify most feasible

adaptation strategies and adaptive capacity of farmers. Decision guide for adaptation

to climate in traditional irrigation farming systems was developed inorder to

integrate the challenges of climate change and those related to adaptive capacity to

enhance adaptation actions.

The results show that for the past 30 years (1985-2014) climate variables such as

annual mean (minimum and maximum) temperature and annual mean rainfall have

been increasing and decreasing respectively in fluctuating patterns. For the past 30

years, annual mean (minimum and maximum temperature) have increased by 0.83oC

and 2.4oC respectively and annual mean rainfall have decreased by 803mm. Climate

change has affected crop yield in Ndiwa and Chamazi traditional irrigation systems

through decrease amount of water for irrigation, outbreak of crop diseases, pests and

insects. Farmers engaged in Ndiwa and Chamazi irrigation systems adopted different

adaptation strategies to combat the impact of climate change. These include

cultivating near water sources, crop diversification, digging of shallow wells and

application of pesticides. However, the adaptive capacity to climate change for

Ndiwa farmers was 41.6% indicating moderate adaptive capacity while that of

Chamazi farmers was 23.6% indicating low adaptive capacity. The decision guide

for adaptation to climate change for traditional irrigation farming systems was finally

proposed with an intention of facilitating Ndiwa and Chamazi farmers to select

appropriate adaption actions to the impact of climate change.

It has been recommended that the government and other stakeholders should extend

their efforts more to help the farmers engaged in Ndiwa and Chamazi irrigation

systems to improve their adaptative capacity to climate change. They should

especially help farmers to access the following; climate informations, land and

security of tenure, water sources, and financial resources, agricultural inputs,

agricultural extension services and improved transport and irrigation infrastructures.

The government, particularly the local government authority of Lushoto, should also

sensitize farmers to establish and strengthen the farmer based organizations. The

central government and other stakeholders should further help in improving

irrigation farming and the coordination between crop research centers, extension and

farmers.