Eucalyptus biochar application enhances Ca uptake of upland rice, soil available P, exchangeable K, yield, and N use efficiency of sugarcane in a crop rotation system

Abstract

It was hypothesized that the application of eucalyptus biochar enhances nutrient use efficiencies of simultaneously supplied fertilizer, as well as provides additional nutrients (i.e., Ca, P, and K), to support crop performance and residual effects on subsequent crops in a degraded sandy soil. To test this hypothesis, we conducted an on-farm field experiment in the Khon Kaen province of Northeastern Thailand to assess the effects of different application rates of eucalyptus biochar in combination with mineral fertilizers to upland rice and a succeeding crop of sugarcane on a sandy soil. The field experiment consisted of three treatments: (1) no biochar; (2) 3.1 Mg ha -1 biochar (10.4 kg N ha -1 , 3.1 kg P ha -1 , 11.0 kg K ha -1 , and 17.7 kg Ca ha -1 ); (3) 6.2 Mg ha -1 biochar (20.8 kg N ha -1 , 6.2 kg P ha -1 , 22.0 kg K ha -1 , and 35.4 kg Ca ha -1 ). All treatments received the same recommended fertilizer rate (32 kg N ha -1 , 14 kg P ha -1 , and 16 kg K ha -1 for upland rice; 119 kg N ha -1 , 21 kg P ha -1 , and 39 kg K ha -1 for sugarcane). At crop harvests, yield and nutrient contents and nitrogen (N) use efficiency were determined, and soil chemical properties and pH 0 monitored. The eucalyptus biochar material increased soil Ca availability (117 28 and 116 7 mg kg -1 with 3.1 and 6.2 Mg ha -1 biochar application, respectively) compared to 71 13 mg kg -1 without biochar application, thus promoting Ca uptake and total plant biomass in upland rice. Moreover, the higher rate of eucalyptus biochar improved CEC, organic matter, available P, and exchangeable K at succeeding sugarcane harvest. Additionally, 6.2 Mg ha -1 biochar significantly increased sugarcane yield (41%) and N uptake (70%), thus enhancing N use efficiency (118%) by higher P (96%) and K (128%) uptake, although the sugar content was not increased. Hence, the application rate of 6.2 Mg ha -1 eucalyptus biochar could become a potential practice to enhance not only the nutrient status of crops and soils, but also crop productivity within an upland rice-sugarcane rotation system established on tropical low fertility sandy soils.

Biochar of residual biomass from eucalyptus (Eucalyptus globulus) by two pyrolysis methods

“…Elementos disponibles (ppm). La caracterización de la biomasa y el biochar a nivel de laboratorio muestra mayor cantidad de elementos disponibles en la materia pirolizada que en la biomasa sin tratar, en lo que respecta a los microelementos especialmente para: cobre, zinc, manganeso y boro, razón por la que el biochar aporta con elementos que están disponibles para las plantas (Escalante et al, 2016;Butphu et al, 2019). Mukherjee y Lal (2016) encontraron evidencias de mejora en las condiciones de los suelos con biochar.…”

“…Sin embargo, estas últimas variables (carbono total y densidad aparente) aunque se encuentran estrechamente conexas, guardan una correlación negativa con los elementos asociados a la prirólisis rápida de ramas y prirólisis lenta de cortezas. Estos resultados confirman que, en su composición, la biomasa de eucalipto se diferencia notoriamente con la materia pirolizada (biochar), lo que indica el cambio en la estructura y composición del biocarbon con los elementos que contiene, confirmando los estudios anteriormente realizados en biochar de eucalipto (Butphu et al, 2019).…”

“…El biochar o biocarbón, se ha relacionado con la gestión del suelo llevada a cabo por diferentes culturas amerindias antes de la llegada de los europeos, como la "terra preta" en Brasil. El uso del biocarbón de eucalipto, aplicado en dosis apropiadas es una técnica que ha demostrado proveer beneficios al suelo plantas y ambiente, aumentando la fertilidad a través de la influencia en sus propiedades físicas, químicas y biológicas y consecuente al desarrollo de las plantas, además contribuye al secuestro de carbono en su estructura (Hagemann et al, 2017, Iglesias, 2018Butphu et al, 2019). El biochar (biocarbón) se produce por la transformación mediante la combustión incompleta o parcialmente anaeróbica (pirólisis) de la biomasa a temperaturas de 350-650 °C, lo que promueve un material rico en contenido de carbono y cenizas, que se devuelven al suelo, mejorando las condiciones del mismo.…”

Photosynthetic Nutrient and Water Use Efficiency of Cucumis sativus under Contrasting Soil Nutrient and Lignosulfonate Levels

“…A wide range of soils are noted for their low nutrient-supplying capacity, and for agricultural purposes they need to be improved with commercial high-cost fertilizers. New economic instruments of improving soil fertility and reducing the cost of agricultural products are currently under study and discussion [1][2][3]. The possibility of using of pulp and paper industry wastes as an alternative source of soil nutrients is also discussed [4,5].…”

“…It can be hypothesized that LS-related modification of leaf nutrient content could affect photosynthetic capacity and/or efficiency of nutrient use. Leaf N and P are both essential nutrients involved in the photosynthetic process, but other leaf nutrients, such as K, Ca, Mg, Fe, Mn, and Na, can modify the photosynthetic capacity [ 21 , 22 ] and affect the photosynthetic efficiency of using of other nutrients, mainly, N and P, as has been shown recently [ 2 , 23 ].…”