Benefits of Biochars and NPK Fertilizers for Soil Quality and Growth of Cowpea (Vigna unguiculata L. Walp.) in an Acid Arenosol

• Published in: Pedosphere Vol. 29; no. 3; pp. 311 - 333
• Main Authors: RAFAEL, Rogério Borguete Alves, FERNÁNDEZ-MARCOS, Maria Luisa, COCCO, Stefania, RUELLO, Maria Letizia, FORNASIER, Flavio, CORTI, Giuseppe
• Format: Journal Article
• Language: English
• Published: Beijing Elsevier Ltd 01.06.2019; Elsevier Science Ltd; Department of Agriculture, Food and Environmental Sciences, Università Politecnica delle Marche, Ancona 60131 Italy%Department of Soil Science and Agricultural Chemistry, Universidad de Santiago de Compostela, Lugo 27002 Spain; Department of Rural Engineering, Faculty of Agronomy and Forestry Engineering, Universidade Eduardo Mondlane, Maputo 257 Mozambique; Instituto de Biodiversidade Agraria e Desenvolvimento Rural, Universidad de Santiago de Compostela, Lugo 27002 Spain%Department of Agriculture, Food and Environmental Sciences, Università Politecnica delle Marche, Ancona 60131 Italy%Department of Materials, Environmental Sciences and Urban Planning, Università Politecnica delle Marche, Ancona 60131 Italy%Centro di Ricerca Viticoltura ed Enologia, Gorizia 34170 Italy
• Subjects: acid soil; Acidic soils; Acids; Branches; Cation exchange; Cation exchanging; Charcoal; Compound fertilizers; Corn; Cowpeas; Dosage; Enzymatic activity; Fertilization; Fertilizer application; Fertilizers; Food production; Leaching; Nitrogen; nutrient use efficiency; Nutrients; Optimization; organic amendment; Organic chemistry; Phosphorus; Phosphorus pentoxide; Plant growth; Potassium; potential enzyme activity; Production costs; Sandy soils; Sediment yield; Soil chemistry; Soil fertility; Soil improvement; Soil investigations; Soil pH; Soil properties; Soil quality; Urea; Vigna unguiculata; Weight; plant growth; soil pH; nutrient use efficiency; organic amendment; acid soil; soil fertility; potential enzyme activity
• ISSN: 1002-0160; 2210-5107
• DOI: 10.1016/S1002-0160(19)60805-2

Fertilization is required for optimum plant growth, particularly in unfertile soils, while optimizing nutrient use efficiency is an alternative to reduce inorganic fertilizer needs and reduce environmental problems caused by nutrient leaching. This study investigated soil properties and cowpea yield responses to biochars (BCs) made from different feedstocks, baby corn peel biochar (BC1), branches of mango tree biochar (BC2), and rice husk biochar (BC3), applied in combination with nitrogen-phosphorus-potassium (NPK) fertilizers. The experiment was conducted in a greenhouse, using an acid sandy soil (Arenosol) that was submitted for 70 d to the following eight treatments: i) control; ii) full dose of NPK (a commercial compound fertilizer (12-24-12 of N-P2O5-K2O) + urea (46% N)); iii) BC1 + half dose of NPK; iv) BC1 + full dose of NPK; v) BC2 + half dose of NPK; vi) BC2 + full dose of NPK; vii) BC3 + half dose of NPK; and viii) BC3 + full dose of NPK. All biochars were applied at a rate of 0.9% (weight/weight), and each type of biochar was combined with half and full doses of NPK fertilizers. Soil pH increased significantly (P < 0.05) in treatments with BC1 and BC2, while cation exchange capacity (CEC) and available P were higher in the treatments with BC1; BC1 and BC2 also induced higher activity of enzymes related to the P cycle and higher cowpea yield. Similar soil properties and cowpea yield parameters were obtained with the full and half doses of NPK fertilizers for each type of biochar used. In conclusion, biochars in the combination with NPK fertilizers improved soil chemistry and enzymatic activities, allowing reduced fertilizer application and food production costs in the acid soil studied.