Journal of Environmental Management 268 (2020) 110664 Available online 14 May 2020 0301-4797/© 2020 Elsevier Ltd. All rights reserved. Research article Role of textile effuent fertilization with biosurfactant to sustain soil quality and nutrient availability Ratan Singh a , Bernard R. Glick b , Dheeraj Rathore a, * a School of Environment and Sustainable Development, Central University of Gujarat, Gandhinagar, 382030, India b Department of Biology, University of Waterloo, Ontario, N2L 3G1, Canada A R T I C L E INFO Keywords: Textile effuent Biosurfactant Soil health Triticum aestivum Capsicum annum ABSTRACT The textile industry is one of the world’s most pollution generating industries, and management of its toxic effuent has become a global issue. However, the use of textile effuent as source of nutrients can be a viable option due to the presence of some essential minerals, although the presence of several toxic elements can deteriorate soil health. Therefore, experiments were conducted to identify the potential of textile effuent fertilization together with biosurfactant amendment to increase the soil health and nutrient status for agricul- tural sustainability. In this study, soil fertilized with different concentrations of textile effuent treatments (i.e. T1A, T2A and T3A) was treated with two different concentrations of biosurfactants to accurately appraise the suitability of a set of soil quality parameters including, physical, chemical, biochemical, and biological activities. A thorough analysis of all soil health parameters was undertaken before sowing the seeds and after cultivation of either Triticum aestivum (cv. LOK-1 and GW-496) or Capsicum annum (cv. GVC-101 and GVC-121). The results indicated that lower concentrations of textile effuent are a good source of nutrients while biosurfactants served as good solubilizers of metals and made it more available at the higher effuent concentration (T2C). Under these conditions, not only did fertilizers signifcantly increased, but also the microbial population as well as the enzymatic activity of soil was enhanced. Lower concentrations of micronutrients in the soil after crop cultivation is attributed to the higher level of their availability to the plants during their growth and development. This study provides new insight into the biosurfactants application to enhance soil micronutrients availability and increase crop productivity using textile effuents as a source of nutrients. 1. Introduction The expected increase in the world’s population (projected to be ~9.6 billion by the year 2050) needs food productivity to be increase signifcantly within the next few decades (Diacono and Montemurro, 2015). Unfortunately, exhausted from years of cultivation, many soils have slowly become more defcient in a variety of essential nutrients, including micronutrients. Micronutrient concentrations in plants refect the nutrient status of soils and the nutrient availability where they are grown (Knez and Graham, 2013). The physical, chemical, biochemical and biological properties of soil determine its health for better crop production and are closely related to nutrient cycles, including soil respiration, microbial biomass, nitrogen mineralization capacity and the activities of soil enzymes (Trasar-Cepeda et al., 2000). Soil biological processes are carried out by many soil microorganisms (Jacoby et al., 2017), and their activities are vital for biogeochemical soil processes (Udawatta et al., 2009). Furthermore, while soil enzymes are only a small fraction of organic matter, they are crucial as all biochemical ac- tions are dependent upon or related to them (Kallenbach et al., 2016). Soil enzymes are important for catalysing innumerable reactions necessary for life processes of microorganisms in soils, decomposition of organic residues, cycling of nutrients and formation of organic matter and soil structure. Effuent of the textile industry is considered to be one of the world’s most polluted industrial effuents consist of a high concentration of heavy metals and organic compounds. Some essential metals necessary for plant metabolism as enzyme activators or regulators, e.g. Fe, Cu, Mn, Zn, and Ni are also present in textile effuent (Kaushik et al., 2005; Hassan et al., 2013; Singh and Rathore, 2018). Besides the presence of minerals and heavy metals, textile effuents also contains organic dyes characterized by strong colour, highly fuctuating pH, high chemical oxygen demand (COD), biological oxygen demand (BOD), sulphide, total solids (TS), total dissolved solids (TDS) and ammonical nitrogen * Corresponding author. E-mail address: dheeraj.rathore@cug.ac.in (D. Rathore). Contents lists available at ScienceDirect Journal of Environmental Management journal homepage: http://www.elsevier.com/locate/jenvman https://doi.org/10.1016/j.jenvman.2020.110664 Received 19 January 2020; Received in revised form 8 April 2020; Accepted 26 April 2020