A Novel Compost for Rice Cultivation Developed by Rice Industrial By-Products to Serve Circular Economy

Abstract

Rice is the major staple crop worldwide, whereas fertilization practices include mainly the application of synthetic fertilizers. A novel compost was developed using 74% of rice industrial by-products (rice bran and husks) and tested in rice cultivation in Greece’s main rice producing area. Field experimentation was conducted in two consecutive growing seasons (2017 and 2018) and comprised six fertilization treatments, including four compost rates (C1: 80, C2: 160, C3: 320 kg ha−1 of nitrogen all in split application, C4: 160 kg ha−1 of nitrogen in single application), a conventional treatment, as well as an untreated control. A total of 21 morpho-physiological and quality traits were evaluated during the experimentation. The results indicated that rice plants in all compost treatments had greater height (8%–64%) and biomass (32%–113%) compared to the untreated control. In most cases, chlorophyll content index (CCI) and quantum yield (QY) were similar or higher in C3 compared to the conventional treatment. C2 and C3 exhibited similar or greater yields, 7.5–8.7 Mg ha−1 in 2017 and 6.3–6.9 Mg ha−1 in 2018, whereas the conventional treatment resulted in 7.3 Mg ha−1 and 6.8 Mg ha−1 in the two years, respectively. No differences were observed in most quality traits that affect the rice commodity. The current study reveals that in sustainable farming systems based on circular economy, such as organic ones, the application of the proposed compost at the rate of 6 Mg ha−1 can be considered sufficient for the rice crop nutrient requirements.

Analysis of the Circular Economic Production Models and Their Approach in Agriculture and Agricultural Waste Biomass Management

“…By observing the net developed from the keyword co-occurrence analysis ( Figure 10 ), it can be noted that the term “bioenergy” is the most relevant. In fact, 19 percent of the articles appearing focus on the use of AWB to produce renewable energy [ 31 , 37 , 44 , 45 , 174 ] ( Figure 11 ). The terms “fertilizers” and “manures” also stand out in this net, as proven by the fact that 10 percent of the articles are about the production of fertilizers from agro-industrial by-products and their use to improve the characteristics of the cultivation soil [ 175 , 176 ].…”

“…Ten-year legacy of organic carbon in non-agricultural (brownfield) soils restored using green waste compost exceeds 4 per mille per annum: Benefits and trade-offs of a circular economy approach X [175] Bioeconomy and the production of novel food products from agro-industrial wastes and residues under the context of food neophobia 2018 X [176] The bioeconomy of microalgal heterotrophic bioreactors applied to agroindustrial wastewater treatment X [177] Camelina and crambe oil crops for bioeconomy-straw utilisation for energy 2020 X [178] The circular economy of agro and post-consumer residues as raw materials for sustainable ceramics X [50] Cellulolytic enzyme production from agricultural residues for biofuel purpose on circular economy approach 2019 X [179] The management of agricultural waste biomass in the framework of circular economy and bioeconomy: An opportunity for greenhouse agriculture in Southeast Spain X X [7] Co-digestion of by-products and agricultural residues: A bioeconomy perspective for a Mediterranean feedstock mixture 2020 X [180] The potential of plantain residues for the Ghanaian bioeconomy-assessing the current fiber value web X [181] By observing the net developed from the keyword co-occurrence analysis (Figure 10), it can be noted that the term "bioenergy" is the most relevant. In fact, 19 percent of the articles appearing focus on the use of AWB to produce renewable energy [31,37,44,45,174] (Figure 11). The terms "fertilizers" and "manures" also stand out in this net, as proven by the fact that 10 percent of the articles are about the production of fertilizers from agro-industrial by-products and their use to improve the characteristics of the cultivation soil [175,176].…”

Biological control of soil-borne phytopathogenic fungi through onion waste composting: implications for circular economy perspective

“…Composting is one of the best and most sustainable methods of agricultural waste recycling because it allows reincorporating nutrients and organic matter into circulation while maintaining the waste-soil-plant production continuum (Jakubus 2020). The use of compost is within the scope of a sustainable agricultural system that provides an ecologically healthy and economically viable crop production, especially when the latter derives from low-value by-products of the cultivated plants (Kadoglidou et al 2019). From an economic perspective, it should be underlined that raw materials used for composting are easily available locally.…”

“…There are multiple current and proved experiences of successful recycling of agricultural waste through composting. For example, Kadoglidou et al (2019) reported that the application of compost from rice by-products on rice paddy fields satisfies crop nutrient requirements, without compromising yield and quality. Meanwhile, Duque-Acevedo et al (2020) reported that self-management of horticultural waste by composting is profitable at real scale.…”

Sustainability, Efficiency, and Circularity of Weedy Rice Management Strategies

“…Rice cultivation provides the main source of subsistence for almost half of the world population; then, several studies aim to recycle rice residues such as straw, bran, and husk. These crop residues can be used to produce for instance new biofertilizer through composting [2,3], new materials for healthy buildings and energy (e.g., biofuels). The rice, duck, fish integrated farming [4] is another well-known system for which circular principles are present.…”