Chen Yongqi, Awais Muhammad, Wu Junfeng, Li Zhenfeng, Abbas Naqvi Syed Muhammad Zaigham, Abdulraheem Mukhtar Iderawumi, Zhang Hao, Wang Ling, Zhang Wei, Raghavan Vijaya, Hu Jiandong
Department of Electrical Engineering, Henan Agricultural University, Zhengzhou, 450002, China.
Henan International Joint Laboratory of Laser Technology in Agriculture Science, Zhengzhou, 450002, China.
Sci Rep. 2024 Jun 23;14(1):14434. doi: 10.1038/s41598-024-65251-6.
Off-line leachate collection from agricultural landscapes cannot guarantee precise evaluation of agricultural non-point source (ANPS) due to geospatial variations, time, and transportation from the field to the laboratory. Implementing an in-situ nitrogen and phosphorous monitoring system with a robust photochemical flow analysis is imperative for precision agriculture, enabling real-time intervention to minimize non-point source pollution and overcome the limitations posed by conventional analysis in laboratory. A reliable, robust and in-situ approach was proposed to monitor nitrogen and phosphorous for determining ANPS pollution. In this study, a home-made porous ceramic probe and the frequency domain reflectometer (FDR) based water content sensors were strategically placed at different soil depths to facilitate the collection of leachates. These solutions were subsequently analyzed by in-situ photochemical flow analysis monitoring system built across the field to estimate the concentrations of phosphorus and nitrogen. After applying both natural and artificial irrigation to the agricultural landscape, at least 10 mL of soil leachates was consistently collected using the porous ceramic probe within 20 min, regardless of the depth of the soil layers when the volumetric soil water contents are greater than 19%. The experimental results showed that under different weather conditions and irrigation conditions, the soil water content of 50 cm and 90 cm below the soil surface was 19.58% and 26.08%, respectively. The average concentrations of NH-N, NO-N, PO are 0.584 mg/L, 15.7 mg/L, 0.844 mg/L, and 0.562 mg/L, 16.828 mg/L and 0.878 mg/L at depths of 50 cm and 90 cm below the soil surface, respectively. Moreover, the comparison with conventional laboratory spectroscopic analysis confirmed R values of 0.9951, 0.9943, 0.9947 average concentration ranges of NH-N, NO-N, and PO, showcasing the accuracy and reliability of robust photochemical flow analysis in-situ monitoring system. The suggested monitoring system can be helpful in the assessment of soil nutrition for precision agriculture.
由于地理空间差异、时间以及从田间到实验室的运输等因素，农业景观的离线渗滤液收集无法保证对农业面源（ANPS）进行精确评估。对于精准农业而言，实施一套配备强大光化学流动分析的原位氮磷监测系统势在必行，这能够实现实时干预，以尽量减少面源污染，并克服传统实验室分析所带来的局限性。本文提出了一种可靠、稳健的原位方法来监测氮和磷，以确定农业面源污染情况。在本研究中，将自制的多孔陶瓷探头和基于频域反射仪（FDR）的土壤水分传感器有策略地放置在不同土壤深度，以便于收集渗滤液。随后，通过在田间构建的原位光化学流动分析监测系统对这些溶液进行分析，以估算磷和氮的浓度。在对农业景观进行自然灌溉和人工灌溉后，当土壤体积含水量大于19%时，使用多孔陶瓷探头在20分钟内始终能收集到至少10毫升的土壤渗滤液，且与土壤层深度无关。实验结果表明，在不同天气条件和灌溉条件下，土壤表面以下50厘米和90厘米处的土壤含水量分别为19.58%和26.08%。在土壤表面以下50厘米和90厘米深度处，NH-N、NO-N、PO的平均浓度分别为0.584毫克/升、15.7毫克/升、0.844毫克/升以及0.562毫克/升、16.828毫克/升和0.878毫克/升。此外，与传统实验室光谱分析的比较证实，NH-N、NO-N和PO平均浓度范围的R值分别为0.9951、0.9943、0.9947，这表明了强大的光化学流动分析原位监测系统的准确性和可靠性。所建议的监测系统有助于精准农业中土壤养分的评估。
