|Watts, Donald - Don|
|BUSSCHER, WARREN - Retired ARS Employee|
Submitted to: Soil Use and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/14/2014
Publication Date: 6/5/2014
Citation: Novak, J.M., Spokas, K.A., Cantrell, K.B., Ro, K.S., Watts, D.W., Glaz, B.S., Hunt, P.G., Busscher, W.J. 2014. Effects of biochars and hyrdochars produced from lignocellulosic and animal manure on fertility of a Mollisol and Entisol. Soil Use and Management. 30:175-181. DOI:10.1111/sum.12113.
Interpretive Summary: By 2050, global population growth is anticipated to increase the earth’s population to between 8.0 and 10.4 billion people. Providing sufficient food for this large population will present a serious challenge. Globally, averaged crop yields by 2050 will need to increase by 60 to 120% of current production levels. Because land availability for agricultural production is declining, higher yields from intensification of cropping systems on remaining prime land or remediating degraded land will be major drivers of future food production. Agricultural land can be made more fertile by the addition of biochar. Biochars contain organic structures and inorganic elements that can improve soil fertility, increase carbon contents, and reduce nutrient leaching losses. We conducted laboratory incubation studies to evaluate the performance of several different biochars using an unfertile, sandy soil and as a comparison, a fertile soil. After incubating several biochar in these two soils at 10 tons per hectare, we found some fertility improvement in the nutrient-poor soil and minimal modifications in the fertile soil. In fact, biochars produced from swine solids increased the soil phosphorus and potassium concentrations, which are critical plant nutrients. Our results showed that the type of biochar and the amount applied are key factors with improving fertility levels in soils.
Technical Abstract: Food supply needed to meet the anticipated increase in global population are expected to cause crop production intensification; thus, maintaining appropriate soil fertility levels is critical. Among the emerging soil fertility amendments are biochars and hydrochars (HC). However, their ability to improve fertility levels in soils possessing vastly different pedogenic characteristics has not been well investigated. In this study, several plant and manure biochars and two blended HC applied at 10 tons per hectare were incubated in pots containing a highly fertile Mollisol (Waukegan series; Sandy-skeletal, mixed, superactive, mesic Typic Hapludoll) and an infertile Entisol (Margate series; Siliceous, hyperthermic, Mollic Psammaquent). During the 124-125 day laboratory incubations, pots were leached four times with deionized H2O with the leachates analyzed for concentrations of dissolved phosphorus (DP) and potassium (DK). After the incubations, both soils were analyzed for fertility characteristics (i.e., pH, cation exchange capacity (CEC), and extractable P- and K). In both soils after biochar additions, there were mixed pH and CEC responses. Both the Mollisol and Entisol treated with swine solid biochar had greater plant extractable P and K contents, which was reflective of the elevated P and K contents in the swine solid biochar. However, most biochars and HC additions at 10 tons per hectare to the Mollisol and Entisol had minimal impact on soil fertility characteristics indicating a low direct fertilization potential. These nutrient contents could be altered through feedstock blending to target a particular fertilization level.