Increased biodiversity can make valuable contributions to food production and security around the world. The role of plant species diversity for “ecological intensification” of agriculture has been widely recognised, but the potential contribution of multi-trophic-level production systems, such as rice-fish coculture, has received less attention. A continuous 4-year experiment (2015e2018) was conducted comparing rice-fish (yellow finless eel and loach) co-culture, and mono-rice planting practices on the Chongming Eco-island of China. During the experiment, pests (insect herbivores and weeds), arthropods, pesticides, grain and marketable fish yield were sampled, soil quality (available nitrogen, phosphorus and potassium, total nitrogen, organic matter content and pH) and rice grain quality (protein content, chalkiness, gel consistency, amylose content) were evaluated, and an economic analysis were performed. Fish decreased herbivore insect abundance by 24.07%, reduced weeds abundance, richness and biomass by 67.62, 62.01 and 58.88% respectively, increased invertebrate predator abundance by 19.48%, and reduced the need for pesticide by 23.4%. Co-culture practice produced an average economic values 10.33% higher than in the mono-rice farming. In addition, rice-fish co-culture enhanced both soil and rice quality. Our results confirm that rice-fish co-culture can be an effective form of ecological intensification, incorporating and contributing ecosystem services in agricultural production and increasing sustainability.
Agricultural intensification has been recognised one of the main reasons for biodiversity loss and related decline in ecosystem functioning due to the conversion of natural habitats into monoculture farming areas (Gagic et al., 2012; Batary et al., 2017 ; Hass et al., 2018; Plue et al., 2018). Intensive use of agrochemicals is reducing environmental quality (Stehle and Schulz, 2015; He et al., 2017; Ruiz and MarAa Dolores, 2018 ~ ), damaging local plant communities (Cassman, 1999; Kremen et al., 2012), and reducing the abundance and richness of beneficial arthropods (Gagic et al., 2012; Kovacs-Hosty anszki et al., 2017 ). The concept of “ecological intensification” has been promoted to redesign agroecosystems, based on the increased use of ecological processes and biodiversity, using resource more efficiently, and decreasing anthropogenic inputs (Bommarco et al., 2013; Pywell et al., 2015; Bowles et al., 2016). In this framework, it has been showed that plant-diversified farming practices can contribute to ecological intensification of agriculture by providing multiple ecosystem services, promoting biological pest control (Redlich et al., 2018; Wan et al., 2018), decreasing the use of pesticides (Tscharntke et al., 2005; Gurr et al., 2016; Zhao et al., 2016), improving soil quality (Cassman, 1999), and enhancing crop yields (Tittonell and Giller., 2013; Gurr et al., 2016). The potential contribution of multi-trophic-level production systems, such as rice-fish co-culture, to ecological intensification has not received as much attention.