Hilmi Erdal

The effects of exchange rate volatility on trade: evidence from Turkish agricultural trade

In this article, an empirical study of the effect of Real Effective Exchange Rate Volatility (REERV) on Agricultural Export (AGX) and Agricultural Import (AGM) in Turkey was conducted. Studied period covers 1995 to 2007. In order to reach REERV, Generalized Autoregressive Conditional Heteroscedasticity (GARCH) (1,1) model was used. Long-term relationship between series was determined using Johansen cointegration test. The direction of this relationship, on the other hand, was determined using pairwise Granger causality. Our empirical results indicated that there was a positive long-term relationship between REERV and AGX series, while there was a negative long-term relationship between REERV and AGM. The relationship is unidirectional for both AGX and AGM series.

The Functional Relationship between Energy Inputs and Fruit Yield: A Case Study of Stake Tomato in Turkey

This research investigated the relationship between fruit yield and energy inputs used in stake tomato production under field conditions in Tokat province, Turkey. Energy use patterns in tomato production were also determined. Cross sectional data were obtained through face-to-face questionnaires given to the farmers who produce stake tomato. The survey studies indicate that the most important energy inputs among overall energy inputs used in stake tomato production are diesel-oil with 42.71%, total fertilizer consumption with 33.25%, human power with 13.26% and machinery with 6.71%. The average stake tomato production within the farms investigated was 98,000 kgha−1, and total energy consumption was 93644.61 MJha−1. Likewise, the energy output-input ratio and energy productivity were calculated as .93 and 1.16, respectively. The results suggest that small size farms were more efficient than large ones in terms of input use. According to the surveys, of the total energy used, 57.12% was in the form of direct energy and 77.54% was in the form of non-renewable energy. The effect of variables that explain stake tomato production was estimated by an econometric model developed using the Cobb-Douglas type function. In this model, stake tomato yield was considered as an endogenous variable, and fertilizer, chemical, machinery, human power, water for irrigation, diesel-oil, and seed energies were treated as exogenous variables. Elasticity coefficients of diesel-oil, human power, fertilizer, chemical, and water energies were found to be statistically significant. These results reveal that stake tomato production in Turkey heavily depends on fossil fuels. Therefore, adoption of new agricultural practices in stake tomato production, and further research on improvement and use of alternative energy sources are required.

An Alternative Energy Source: Biofuel and Its Position in Turkey

Abstract In this study, major agricultural products that come to the fore in the production of biofuels (biodiesel and bioethanol), some alternative energy sources, have been determined for Turkey. Besides, developments in biomass use in the world and the European Union have been evaluated. For these purposes, using the statistical data about production regions, production amounts, yields, and support status of the agricultural products that are actually used or will be used in the future, opportunities and threats in the future of biofuel production have been discussed, and some suggestions have been made.