TY - JOUR
T1 - Application of olive mill waste-based biochars in agriculture
T2 - Impact on soil properties, enzymatic activities and tomato growth
AU - El-Bassi, Leila
AU - Azzaz, Ahmed Amine
AU - Jellali, Salah
AU - Akrout, Hanene
AU - Marks, Evan A.N.
AU - Ghimbeu, Camélia Matei
AU - Jeguirim, Mejdi
N1 - Funding Information:
This research was funded by the FERTICHAR project, funded through the ARIMNet2-2017- Joint Call by the following funding agencies: MHESRT (Tunisia), ANR (France), and HAO332 DEMETER (Greece). ARIMNet2 (ERA-NET) has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 618127. The authors gratefully acknowledge the funding agencies for their support.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/2/10
Y1 - 2021/2/10
N2 - The olive oil industry is an important economic sector in Mediterranean countries. However, oil production is unfortunately accompanied by the generation of huge amounts of olive mill solid wastes (OMSW) and olive mill wastewater (OMWW). In the present study, a strategy is proposed for converting these olive mill wastes into biochar through pyrolysis, for their later use as an organic amendment in agriculture. Specifically, two biochars were prepared from the pyrolysis of OMSW at 500 °C, either alone or impregnated with OMWW (OMSW-B and I-OMSW-B). The characterization of the OMSW and I-OMSW samples and their derived biochars showed that the fixed carbon and ash contents in the feedstocks increased by 38% and 11% respectively for OMSW-B, and by 37% and 12% respectively for I-OMSW-B. Interestingly, the impregnation process significantly increased Na, P, K, Ca and Fe contents in the produced biochars. The effect of OMSW-B and I-OMSW-B amendments at different application dose (1%, 2.5% and 5% wt/wt) on the enzymatic activity of an agricultural soil was performed at laboratory scale with a pot test. The experimental results showed that phosphatase and urease activity increased with biochar application rate; amendment with I-OMSW-B at 1%, 2.5% and 5% enhanced the phosphatase activity by 63%, 142% and 285% and urease activity by 50%, 116% and 149%, respectively. On the other hand, dehydrogenase and protease activities were higher for the application rate of 2.5% biochar. Biochar amendment promoted tomatoes seedling growth after 10 weeks, which was highest in the application rates of 2.5% and 5% for both OMSW-B and I-OSMW-B. Thus, the produced biochars had great potential to be used as biofertilizers in agriculture.
AB - The olive oil industry is an important economic sector in Mediterranean countries. However, oil production is unfortunately accompanied by the generation of huge amounts of olive mill solid wastes (OMSW) and olive mill wastewater (OMWW). In the present study, a strategy is proposed for converting these olive mill wastes into biochar through pyrolysis, for their later use as an organic amendment in agriculture. Specifically, two biochars were prepared from the pyrolysis of OMSW at 500 °C, either alone or impregnated with OMWW (OMSW-B and I-OMSW-B). The characterization of the OMSW and I-OMSW samples and their derived biochars showed that the fixed carbon and ash contents in the feedstocks increased by 38% and 11% respectively for OMSW-B, and by 37% and 12% respectively for I-OMSW-B. Interestingly, the impregnation process significantly increased Na, P, K, Ca and Fe contents in the produced biochars. The effect of OMSW-B and I-OMSW-B amendments at different application dose (1%, 2.5% and 5% wt/wt) on the enzymatic activity of an agricultural soil was performed at laboratory scale with a pot test. The experimental results showed that phosphatase and urease activity increased with biochar application rate; amendment with I-OMSW-B at 1%, 2.5% and 5% enhanced the phosphatase activity by 63%, 142% and 285% and urease activity by 50%, 116% and 149%, respectively. On the other hand, dehydrogenase and protease activities were higher for the application rate of 2.5% biochar. Biochar amendment promoted tomatoes seedling growth after 10 weeks, which was highest in the application rates of 2.5% and 5% for both OMSW-B and I-OSMW-B. Thus, the produced biochars had great potential to be used as biofertilizers in agriculture.
KW - Biochar
KW - Biofertilization
KW - Olive mill wastes
KW - Pyrolysis
KW - Tomato growth
UR - http://www.scopus.com/inward/record.url?scp=85092137624&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85092137624&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2020.142531
DO - 10.1016/j.scitotenv.2020.142531
M3 - Article
C2 - 33035975
AN - SCOPUS:85092137624
SN - 0048-9697
VL - 755
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 142531
ER -