A Measurement of Conservation Agriculture's Effect on Nitrogen and Carbon Cycling for Agriculture Recommendation in Haiti's Central Plateau.

Due to deforestation, 60-80% of total Haitian land mass is affected by erosion. Low agricultural productivity due to this unprecedented soil erosion, lack of inputs, and lack of knowledge of improved farming practices, contribute greatly to Haiti’s food insecurity and hinder adoption of conservation agricultural practices.  In rural Lower Plateau, Haiti, a household survey of 600 farmers reported only 5.7% of households used compound fertilizer, less than .5% applied manure, and no one applied compost (Kennedy, 2012).  Therefore, a niche exists for assessing cover crop residues for decomposition rate and nutrient cycling as an important step in making informed choices about which cover crop species offer the greatest advantage in providing chemical nutrients for subsequent crops in hopes of increased yield. To assess carbon (C) and nitrogen (N) cycling and the rate of decomposition of surface-placed and buried field and cover crop residues, a field experiment in a sandy-loam soil was initiated near Corporant, Haiti in May, 2013.  Residue from two food crops, maize (Zea mays L.) and common bean (Phaseolus vulgaris L.), and two promising cover crops, sunnhemp (Crotalaria juncea L.) and sorghum sudangrass (Sorghum bicolor) were placed in litterbags either on the soil surface or buried at a depth of 15 cm.  Mass loss over time, % nitrogen (N) evolution, and % carbon (C) evolution were measured across six sampling dates and analyzed utilizing Loss on Ignition combustion to determine C:N ratios for each residue and placement.