Rainfall Variability and its Effect on Yield of Rice in Nigeria

Abstract

ABSTRACT. Nigerian rice production is mainly rain-fed and naturally prone to vagaries of rainfall variability. The objective of this study was to determine the probable effect of rainfall variability on average yield of rice in Nigeria during a 22-year period . The mean annual rainfall data from major rice producing states and national average rice yields were analyzed using descriptive statistics and regression models. Results of the analysis revealed a significant variation in mean annual rainfall across vegetation grouping in a descending order from swamp forest to Sudan savanna. Mean rainfall was adequate for rice production in all vegetation grouping except Sudan savanna where rainfall was less than the prescribed minimum quantity for rice production. Rainfall was positively related to yield of rice in all vegetation grouping except Sudan savanna but relationship was not statistically significant at 5% level. It was concluded that annual rainfall variability had statistically negligible effect on national average rice yield. It was recommended that the cultivation of rice should go along with farming practices that aimed at mitigating adverse effects of rainfall variability on the yield of rice especially in the Sudan savanna.

Utilization of climate change adaptation strategies among rice farmers in three states of Nigeria

“…The degree and intensity at which rains are experienced in recent times is far beyond what farmers are familiar and can grapple with in order to remain productive. According to Tiamiyu et al (2015), extreme rainfall variability triggers environmental problems such as floods, gully erosion, drought and desertification which have serious effects on rice yield. While floods wash away and destroy rice farmlands as well as those of other staples thereby creating a heavy yield loss to farmers who spend much establishing the crop farms, increase in temperature on the other hand shortens the duration between sowing and harvesting in rice cycles and this adversely affects yield as it leads to early occurrence of senescence (National Research Council (NRC), 2011).…”

Impacts of El Niño-Southern Oscillation (ENSO) on Rice Production in Thailand during 1961-2016

“…Similar to the relationship with MEI, higher correlation coefficients were in general found for rice production and yield which percentages of variability explained by each of these climate variables were, on an average, 23% (Figure 3, Figure 4, and Figure 5). Strong relationships between rainfall variability and rice production and yield were previously reported in the Ganges-Brahmaputra Basin (Asada and Matsumoto, 2009), Vietnam (Chung et al, 2015), Nigeria (Tiamiyu et al, 2015) and Cambodia (Pheakdey et al, 2017). In addition, Thailand's rice production, area harvested and yield showed negative correlations with annual mean surface air temperature but only the correlation coefficient of production was significant at the 95 confidence level ( Figure 6).…”

“…Long-term trends often present in the rice production, area harvested and yield data as a result of technological advances and additional farming techniques. The Ordinary Least Square (OLR) method (Tiamiyu et al, 2015;Pheakdey et al, 2017;Rahman et al, 2017) was then used to detrend for each of those time series. This method is robust to the effect of outliers in the series and is more suitable for estimating linear trend of non-normally distributed data.…”

“…A correlation was taken to be significant when the nocorrelation null hypothesis was exceeded with a probability of 95% and highly significant when the probability was 99% (Zubair, 2002;Asada and Matsumoto, 2009). A multiple linear regression was also analyzed to quantify the impact of ENSO and climate variability on rice production and yield where significant correlations had been found (Roberts et al, 2009;Tiamiyu et al, 2015;Rahman et al, 2017).…”

Analysis of Farmers' Vulnerability to Climate Change in Niger State, Nigeria

“…Farmers in African countries have been identified as most vulnerable to climate change due to their low adaptive capacities [4][5][6]. In Nigeria, the climate change impacts cut across various sectors, but agriculture is the most vulnerable due to their dependent on rain-fed agriculture [7]. Consequently, agriculture is the dominant sector in the Niger State economy.…”