Soil-moisture ‘retention’ by Trigonella foenum-graecum L. for Loamy Soil with smart monitoring using FC-28 Sensors

Abstract

In the era of rampant industrialisation, production of food crops and cash crops is still pertinent to the growing economy [1]. Hence, its derailment can impair any nation’s progress w.r.t. agro-based revenue generation. The health of any nation is therefore necessarily dependent upon its agricultural produce. A major issue currently faced by agriculturists and farmers in enhancing the quality and quantity of their produce; is the challenges faced with on-going water scarcity aggravated by urbanisation and climate change crisis [2]. This issue subsequently impacts the availability of soil-moisture which is by most important for the cultivation of crops [3]. The present measures which are being employed to enhance retention levels of soil-moisture are costly and hazardous due to chemical additives. This further tends to have severe environmental consequences such as ground water pollution, soil degradation, reduced yield; and eventually compromising human health with carcinogenic consequences over the long run [4-5].

The present study attempts to offer a sustainable organic solution to overcome the perils of the present chemical-laden practices in the modern agro-based practices. The research envisages performance evaluation of Trigonella foenum-graecum L. (Fenugreek) as an alternative able-replacement, which invariably also reduces the inadvertent impacts of impended water scarcity. Fenugreek is an annual legume plant in the family fabaceae, cultivated worldwide as a semi-arid crop [6]. This study attempts to take benevolence from the fact that the fenugreek seed contains a high proportion of mucilage with hydrophilic galactomannan [7]. Thereby, the hydrogel properties are being sought for entrapment of water molecules, when applied over the soil layer towards enhancing the overall moisture content of the soil. Therefore, this study attempts to encompass and contribute towards water conservation in agricultural practices, alongside economic savings, with respect to reduced application of water in stadiums, gardening and lawn maintenance etc. 

The research scope focuses on feasibility studies upon the role of Fenugreek-based Hydrogel in loamy soil towards successful augmentation of soil-moisture retention capacity. To attain the research objectives, Extensive Literature Survey was carried out followed by determination of sample size for lab-scale analysis. Further, various lab-scaled experiments (in adherence to IS codes) for desired properties were undertaken [8]. Finally, comparative performance analysis with synthetic hydrogel was determined. The parametric variables included soil p^H (figure1-A), depth of application, dosage of natural hydrogel, quantity of water and other soil characteristics etc. Throughout the study, FC-28 (soil moisture sensors) with ESP8266 (Wi-Fi module) and DS3231 (RTC timer) were employed to facilitate smart monitoring and real-time determination. 

The results of this study divulge the following highlights. As can be observed from figure 1-B, while the results indicate that synthetic hydrogel was able to retain the soil-moisture by a maximum of 69.30%, the natural hydrogel was able to peak only upto 37.40%; without any further addition of water for the 9 hours’ span. However, while the synthetic based hydrogel was comparatively more efficient with 37% in the initial 1 hour of application, its potential had decreased by 4.68% by next 5 hours and by a maximum of 11.79% by 9 hours. Contrastingly, while the initial retention ability was far too less by natural hydrogel (4.55% in 1^st hour); but as time elapsed, its retention decreased only by 2.04% and 5.08% with a passage of 5 and 9 hours respectively. When comparison is undertaken between synthetic and natural hydrogel, the difference of efficiency hardly exceeds 31%. From this study finding, it can be hence affirmed about the long-term effectiveness of natural hydrogel (from ‘Fenugreek-gum Extract’) for loamy soil. It can be concluded that the product (Natural Hydrogel) developed can deliver similar results/functions to that of a synthetic hydrogel, and as well can replace/alter attitude towards the usage of unsafe chemicals.

Also as the manufacturing process is easy, the production cost for a wholesale market delivers it as an affordable alternative. As an economical commodity, the Natural Hydrogel can largely benefit the farming community without heavy reliance on Monsoons and irrespective of soil-porosity/permeability. Significantly there would also be enhanced growth yield and reduced soil degradation. The eventual outcome of the research is the development of a product which will be beneficial to agriculture, plantation and forest belt, w.r.t. various circumstances and divided goals. In sync/compliance with Sustainability Development Goals, the future scope of this study delves to incorporate AI based real time detection for temporal performance for other types of soil.