Long-Term Trends in Soil Fertility under Agricultural Plantations in Tropical Regions.
Alfred Hartemink, ISRIC - World Soil Information, PO Box 353, Wageningen, 6700 AJ, Netherlands
Agricultural plantations with perennial crops are a major source of revenue for many tropical countries. It is often perceived that perennial cropping systems are sustainable because of the use of inorganic fertilizers, lime, and other amendments. Trends in soil fertility can be studied because soil analytical data are commonly available from many years. Such data were collected as part of soil surveys and to assess soil nutrient status and fertilizer applications. In this paper, methodologies are presented to show how long-term data on soil fertility of agricultural plantations can be used. A meta-analysis is presented of data from all over the world including detailed studies on sugar cane and sisal plantations. The analysis is compared to trends in soil analytical data from annual cropping systems in tropical regions. The analysis has shown that data from agricultural plantations are useful to assess long-term trends in soil fertility.