Environmental Sciences and Sustainable Engineering Centre (ESSENCE)

Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

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IIT Palakkad

Land treatment of municipal wastewater effluent is a proven method for augmenting freshwater resources and avoiding direct nutrient discharges to surface waters. We assessed changes in soil test phosphorus (P) of the Ap horizon of cropped fields continuously irrigated for 26 yr with secondary effluent from the Penn State University wastewater treatment plant. For annual P additions averaging 97 kg P ha-1, Mehlich-3 P (M3P) response in the 0- to 20-cm surface soil (initially &lt;20 mg kg-1) was represented by two lines. For the first 12 yr of irrigation, soil test P increased, with 14.5 kg P ha-1 needed to increase M3P by 1 mg P kg-1. After the initial buildup, M3P maintained a quasi-steady-state value of ∼110 mg kg-1. Over time, the surface soil equilibrium P concentration at zero sorption increased markedly (from &lt;1 to 5.5 mg P L-1), and extractable aluminum (Al) decreased significantly (P &lt; 0.001). Speciation modeling using Visual MINTEQ suggests complexation of Al by dissolved organic carbon at site pH conditions. Loss of Al from the surface layer lowered its P-sorbing capacity, causing added effluent-P to move into the subsoil. Results suggest that current management practices can continue for many years without exceeding the surface soil M3P environmental threshold (200 mg kg-1) used in state P-based nutrient policies. Copyright © 2011 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

World University root node

Journal of Environmental Quality

Long-term phosphorus fertility in wastewater-irrigated cropland

The Pennsylvania State University

Soil phosphorus dynamics in a sprinkler irrigation system for land application of municipal wastewater effluent

Vegetated buffers strips typically have limited ability to reduce delivery of dissolved phosphorus (DP) from agricultural fields to surface waters. A field study was conducted to evaluate the ability of buffer strips enhanced with drinking water treatment residuals (WTRs) to control runoff P losses from surface-applied biosolids characterized by high water-extractable P (4 g kg -1). Simulated rainfall (62.4 mm h-1) was applied to grassed plots (3 m x 10.7 m including a 2.67 m downslope buffer) surface-amended with biosolids at 102 kg P ha-1 until 30 min of runoff was collected. With buffer strips top-dressed with WTR (20 Mg ha-1), runoff total P (TP = 2.5 mg L-1) and total DP (TDP =1.9 mg L -1) were not statistically lower (α = 0.05) compared to plots with unamended grass buffers (TP = 2.7 mg L-1; TDP = 2.6 mg L -1). Although the applied WTR had excess capacity (Langmuir P maxima of 25 g P kg-1) to sorb all runoff P, kinetic experiments suggest that sheet flow travel time across the buffers (∼30 s) was insufficient for significant P reduction. Effective interception of dissolved P in runoff water by WTR-enhanced buffer strips requires rapid P sorption kinetics and hydrologic flow behavior ensuring sufficient runoff residence time and WTR contact in the buffer. Substantial phosphate-adsorbent contact opportunity may be more easily achieved by incorporating WTRs into P-enriched soils or blending WTRs with applied P sources. Copyright © 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.