Soil security for developing and sustaining Papua New Guinea soil under cocoa

摘要: Soil security is an important concept for informing the theory and practice of development agriculture. The concept of Soil Security provides a means to evaluate the biophysical condition of the soil (condition and capability) but also aspires to assess the way people connect to, and value, soil as a form of natural capital. PNG produces high quality cocoa, mostly relying on the current soil conditions and without the use of fertiliser. Overtime this continuous export of nutrients (a metric tonne of harvested pods contain on average 29.7 kg N, 5.8 kg P, and 47.8 kg K) without replacement may diminish the condition of soil and yield in future, highlighting the need for an integrative approach to developing management options for securing PNG Soil under Cocoa. Contrary to popular belief, that cocoa needs deep soil, cocoa has the capability to grow in PNG on shallow calcareous soils such as Rendolls as long as the feeder roots can access nutrients and water. However, texture contrast soils and stony soils unable to hold nutrients may not be desired for cocoa growth. Further, soils have intrinsic nutrient deficiencies at times, as an example, Andisols in East New Britain and Bougainville may be deficient in P due to fixation by Allophane. Therefore, managing soil condition may require soil types specific approaches. There is rarely, if ever, one-size-fits-all solution, and as with many developing countries, the capacity of cocoa producers in PNG to implement interventions is heavily constrained by the prevailing social, economic and environmental context. Accordingly, there exists a need for an integrative approach to developing management options for …