Global Journal of Science Frontier Research, H: Environment & Earth Science, Volume 21 Issue 6

26. 203.96 2011 19.80 4039.06 27. 205.40 2012 20.46 4203.66 28. 219.70 2013 19.50 4283.98 29. 225.00 2014 19.43 4370.60 30. 223.70 2015 19.51 4365.20 Table 4: Data presentation of annual rainfall, maximum temperature, minimum temperature and yam yield Year Rainfall (mm) Max. Temperature ( 0 C) Min. Temperature ( 0 C) Yam Yield (Mt/Ha) 2001 1414.1 407.7 263.5 16.90 2002 1192.7 412.1 265.9 14.52 2003 1406.8 411.6 270.2 15.80 2004 1305 407.1 266.9 16.23 2005 1290.7 411.2 273.9 19.60 2006 1319.9 414.9 276.3 21.69 2007 1595.7 417.1 252.6 1.31 2008 1138 420.7 251.1 20.21 2009 1595.7 417.1 252.6 18.31 2010 1322 416 289.1 21.69 2011 1253.6 408.3 270.9 19.80 2012 1324.7 403.5 270.9 20.46 2013 1259 403.5 276.7 19.50 2014 1332 445.6 272.7 19.43 2015 1261 404.5 286.6 19.51 Pearson Correlations Table 1 Table 5: Correlations Yam yield Rainfall Max temperature Min temperature Pearson Correlation 1 Yam yield Sig. (2-tailed) N 15 Pearson Correlation .079 1 Rainfall Sig. (2-tailed) .779 N 15 15 Pearson Max temperature Correlation .168 .131 1 Sig. (2-tailed) .551 .642 N 15 15 15 Pearson Min temperature Correlation .413 -.053 -.129 1 Sig. (2-tailed) .126 .851 .646 N 15 15 15 15 Note: 0, weak; 1, perfect; -, negative; + positive correlation IV. C orrelation A nalysis Table 4.5 shows a weak positive correlation between rainfall and yam yield in Nasarawa state, to examine these two variables, the Pearson correlation analysis was used. The result of the correlation was established to be 0.079 which connote a weak positive relationship between rainfall and yam yield in Nasarawa state this accounts for 10% to 20% of relationship between rainfall and yam yield, while that of maximum temperature was established to be 0.168 which connote a weak positive relationship between maximum temperature and yam yield but it’s a bit higher than that of rainfall, this means that rainfall does not have a direct effect on yam yield but it could be considered with other factors as soil type, seed, soil pH etc, that of minimum temperature was established to be 0.413, which connote a weak positive relationship, but in this case the value is higher than that of both rainfall and maximum temperature. This is to say yam yield require little rainfall and minimum temperature to produce a bountiful harvest, or it could also require a high amount of rainfall Analysis of Rainfall and Temperature Patterns on Yam Yield in Lafia, Nasarawa State, Nigeria © 2021 Global Journals 1 Global Journal of Science Frontier Research Volume XXI Issue VI Year 2021 40 ( H ) Version I Nigerian Meteorological Agency, Lafia (NIMET, 2001-2015)