0 The Favorability of Rice-Agroforestry: A Meta-Analysis on Yield and Soil Parameters

In many parts of the world rice is the stable food, responsible for up to two thirds of the calorie consumption. Many small scale farmers have limited access to inorganic fertilizer. The purpose of this study is to investigate how agroforestry practices affect rice yield and the soil parameters carbon, nitrogen and phosphorous; and under what circumstances is it favorable for small scale rice farmers to adopt agroforestry practices? In the present study we review the theory of rice production and agroforestry. A meta-analysis has been conducted on rice yield and soil properties, C, N and P, in rice-agroforestry as compared to conventional rice farming. 297 studies were reviewed whereof ten studies fulfilled the requirements and were included in the meta-analysis. The yield results showed that when no mineral fertilizer is available rice yield significantly increased by 36 % (P=0.05) with the introduction of agroforestry. On the other hand if mineral fertilizer is available the results showed conventional farming yielded 28% more than agroforestry (P=0.0002). Generally we dealt with two groups of agroforestry practices. Systems with trees in the field, and systems with tress away from the field. The results show a clear difference between having trees in the field, as compared to away from the field. The result showe