Climate variability is considered as the most serious challenge threatens the ecosystem, whether in developing or developed countries. Climate variability affects the agro ecological and growing conditions of crops and livestock that may add significantly to the development challenges of ensuring food security and reducing poverty. In this study, the climate data for the period (1945-2010) was investigated to determine the manifestation of climate variability in the northwest of Libya and its effect on agriculture. The results indicate that the drop in rainfall volumes and irregular distributed over the season and temperature increasing over the study period are the most important consequences of climate variability in Libya, which has a negative influence on the country’s agriculture sector. Time trend of rainfall and temperature were analyzed and the impacts of climate change on agriculture were discussed. Moreover, Pairwise Granger causality test analysis were used to examine the causal relationship between climatic conditions in Libya. The results further indicate that there is an unidirectional relationship existed between changes in temperature and the production of dates and tomatoes, and unidirectional causality runs from rainfall to onion, potatoes olive and ground peanut.
Nagib M. said Froja, Khaled R. Elbeydi(12-2016)

This article compares two fuzzy approaches to land suitability evaluations, Analytical Hierarchy Process (AHP) and Ideal Point. The methods were evaluated using a case study which models the opportunities for wheat production under irrigation conditions in the north‐western region of Jeffara Plain, Libya. A number of relevant soil and landscape criteria were identified through a review of the literature and their weights specified as a result of discussions with local experts. The results of the Fuzzy AHP showed that the majority of the study area has membership values to the set of suitability between 0.40 and 0.50, while the results of the Ideal Point approach revealed most of the study area to have membership values between 0.30 and 0.40. While the Fuzzy AHP and Ideal Point approaches accommodate the continuous nature of many soil properties and produce more intuitive distributions of land suitabilities values, the Fuzzy AHP approach was found to be better than Fuzzy Ideal Point. This was due to the latter's tendency to be biased towards positive and negative ideal values
Mukhtar Elaalem, Alexis Comber, Pete Fisher(6-2011)

Abstract—The soil moisture content is an important property of the soil. The results of mean weekly gravimetric soil moisture content, measured for the three soil layers within the A horizon, showed that it was higher for the top 5 cm over the whole period of monitoring (15/7/2004 up to 10/11/05) with the variation becoming greater during winter time. This reflects the pattern of rainfall in Ireland which is spread over the whole year and shows that light rainfall events during summer time were compensated by loss through evapotranspiration, but only in the top 5 cm of soil. This layer had the highest porosity and highest moisture holding capacity due to the high content of organic matter. The gravimetric soil moisture contents of the top 5 cm and the underlying 5-15 and 15-25 cm layers show that bottom site of the Hill Field had higher soil moisture content than the middle and top sites during the whole period of monitoring. Keywords— Soil, Soil moisture, Gravimetric soil moisture content. arabic 7 English 39
ِAbdulfatah Faraj Abdullaha Aboufayed(1-2013)