Department of Environmental Science, Faculty of Science, Chulalongkorn University, Bangkok, Thailand; Water Science and Technology for Sustainable Environment Research Unit, Chulalongkorn University, Bangkok, 10330, Thailand.
Thammasat School of Engineering, Thammasat University, Pathumthani, Thailand.
J Environ Manage. 2023 Aug 1;339:117860. doi: 10.1016/j.jenvman.2023.117860. Epub 2023 Apr 20.
Food waste is rich in nutrients, such as nitrogen and phosphorus, and can be integrated with bioponics, a closed-loop agricultural system that combines hydroponics with biological nutrient recovery. Vermicompost leachate (VCL) supplementation has been shown to improve the co-composting of organic waste (i.e., compost quality) and the biodegradation of organic compounds. Thus, VCL has high potential for enhancing nutrient availability in bioponics from food waste. However, the understanding of nitrogen and phosphorus availability in food waste-based bioponics is limited, both with and without VCL. In this study, food waste derived from cafeteria vegetable waste was used as the substrate (500 g dry wt./system) in bioponics to grow lettuce (Lactuca sativa L.) for two consecutive cycles (35 days/cycle) without substrate replacement. VCL was applied weekly (1-5% v/v) and compared to the control without VCL. The results showed that the food waste in bioponics provided nitrogen and phosphorus for plant growth (15.5-65.8 g/lettuce head). Organic-degrading and nutrient-transforming bacteria (Hydrogenispora, Clostridium_sensu_stricto_1, Ruminiclostridium_1, Cellvibrio, Thauera, Hydrogenophaga, and Bacillus) were predominantly found in plant roots and residual food waste. VCL addition significantly increased nitrate, phosphate, and chemical oxygen demand levels in bioponics, owing to the nutrients in VCL and the enhancement of keystone microorganisms responsible for organic degradation and nutrient cycling (e.g., Ellin6067, Actinomyces, and Pirellula). These findings suggest that nitrogen, phosphorus, and organic carbon concentrations in an ecosystem of nutrient-transforming and organic-degrading microbes are key in managing nutrient recovery from food waste in bioponics.
食物垃圾富含氮、磷等营养物质，可与生物培水系统结合，该系统是一种将水培法与生物营养回收相结合的闭环农业系统。已证明，添加蚯蚓粪滤液（VCL）可改善有机废物（即堆肥质量）的共堆肥和有机化合物的生物降解。因此，VCL 具有提高基于食物垃圾的生物培水系统中养分可用性的巨大潜力。然而，无论是有无 VCL，人们对基于食物垃圾的生物培水系统中氮和磷的可用性的理解都很有限。在这项研究中，以食堂蔬菜废物为原料的食物垃圾被用作生物培水系统的基质（系统中 500 g 干重/系统），用于连续两个周期（35 天/周期）种植生菜（Lactuca sativa L.），而不更换基质。每周应用 VCL（1-5%v/v）并与无 VCL 的对照进行比较。结果表明，生物培水系统中的食物垃圾为植物生长提供了氮和磷（15.5-65.8 g/生菜头）。有机降解和养分转化细菌（Hydrogenispora、Clostridium_sensu_stricto_1、Ruminiclostridium_1、Cellvibrio、Thauera、Hydrogenophaga 和 Bacillus）主要存在于植物根系和残留的食物垃圾中。VCL 的添加显著增加了生物培水系统中的硝酸盐、磷酸盐和化学需氧量水平，这是由于 VCL 中的养分以及对有机降解和养分循环负责的关键微生物（如 Ellin6067、放线菌和 Pirellula）的增强。这些发现表明，在养分转化和有机降解微生物的生态系统中，氮、磷和有机碳浓度是管理生物培水系统中从食物垃圾中回收养分的关键。
